diff options
Diffstat (limited to 'kernel/debug')
| -rw-r--r-- | kernel/debug/Makefile | 1 | ||||
| -rw-r--r-- | kernel/debug/debug_core.c | 455 | ||||
| -rw-r--r-- | kernel/debug/debug_core.h | 5 | ||||
| -rw-r--r-- | kernel/debug/gdbstub.c | 76 | ||||
| -rw-r--r-- | kernel/debug/kdb/.gitignore | 1 | ||||
| -rw-r--r-- | kernel/debug/kdb/Makefile | 1 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_bp.c | 98 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_bt.c | 129 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_debugger.c | 19 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_io.c | 607 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_keyboard.c | 43 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_main.c | 1378 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_private.h | 60 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_support.c | 582 |
14 files changed, 1682 insertions, 1773 deletions
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile index a85edc339985..332ee6c6ec2c 100644 --- a/kernel/debug/Makefile +++ b/kernel/debug/Makefile @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only # # Makefile for the linux kernel debugger # diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 0506d447aed2..0b9495187fba 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Kernel Debug Core * @@ -22,11 +23,10 @@ * * Original KGDB stub: David Grothe <dave@gcom.com>, * Tigran Aivazian <tigran@sco.com> - * - * This file is licensed under the terms of the GNU General Public License - * version 2. This program is licensed "as is" without any warranty of any - * kind, whether express or implied. */ + +#define pr_fmt(fmt) "KGDB: " fmt + #include <linux/pid_namespace.h> #include <linux/clocksource.h> #include <linux/serial_core.h> @@ -46,10 +46,13 @@ #include <linux/init.h> #include <linux/kgdb.h> #include <linux/kdb.h> +#include <linux/nmi.h> #include <linux/pid.h> #include <linux/smp.h> #include <linux/mm.h> #include <linux/rcupdate.h> +#include <linux/irq.h> +#include <linux/security.h> #include <asm/cacheflush.h> #include <asm/byteorder.h> @@ -61,9 +64,7 @@ static int kgdb_break_asap; struct debuggerinfo_struct kgdb_info[NR_CPUS]; -/** - * kgdb_connected - Is a host GDB connected to us? - */ +/* kgdb_connected - Is a host GDB connected to us? */ int kgdb_connected; EXPORT_SYMBOL_GPL(kgdb_connected); @@ -76,7 +77,7 @@ static int exception_level; struct kgdb_io *dbg_io_ops; static DEFINE_SPINLOCK(kgdb_registration_lock); -/* Action for the reboot notifiter, a global allow kdb to change it */ +/* Action for the reboot notifier, a global allow kdb to change it */ static int kgdbreboot; /* kgdb console driver is loaded */ static int kgdb_con_registered; @@ -90,14 +91,6 @@ int dbg_switch_cpu; /* Use kdb or gdbserver mode */ int dbg_kdb_mode = 1; -static int __init opt_kgdb_con(char *str) -{ - kgdb_use_con = 1; - return 0; -} - -early_param("kgdbcon", opt_kgdb_con); - module_param(kgdb_use_con, int, 0644); module_param(kgdbreboot, int, 0644); @@ -123,7 +116,6 @@ static DEFINE_RAW_SPINLOCK(dbg_slave_lock); */ static atomic_t masters_in_kgdb; static atomic_t slaves_in_kgdb; -static atomic_t kgdb_break_tasklet_var; atomic_t kgdb_setting_breakpoint; struct task_struct *kgdb_usethread; @@ -159,31 +151,37 @@ early_param("nokgdbroundup", opt_nokgdbroundup); /* * Weak aliases for breakpoint management, - * can be overriden by architectures when needed: + * can be overridden by architectures when needed: */ int __weak kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt) { int err; - err = probe_kernel_read(bpt->saved_instr, (char *)bpt->bpt_addr, + err = copy_from_kernel_nofault(bpt->saved_instr, (char *)bpt->bpt_addr, BREAK_INSTR_SIZE); if (err) return err; - err = probe_kernel_write((char *)bpt->bpt_addr, + err = copy_to_kernel_nofault((char *)bpt->bpt_addr, arch_kgdb_ops.gdb_bpt_instr, BREAK_INSTR_SIZE); return err; } +NOKPROBE_SYMBOL(kgdb_arch_set_breakpoint); int __weak kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt) { - return probe_kernel_write((char *)bpt->bpt_addr, + return copy_to_kernel_nofault((char *)bpt->bpt_addr, (char *)bpt->saved_instr, BREAK_INSTR_SIZE); } +NOKPROBE_SYMBOL(kgdb_arch_remove_breakpoint); int __weak kgdb_validate_break_address(unsigned long addr) { struct kgdb_bkpt tmp; int err; + + if (kgdb_within_blocklist(addr)) + return -EINVAL; + /* Validate setting the breakpoint and then removing it. If the * remove fails, the kernel needs to emit a bad message because we * are deep trouble not being able to put things back the way we @@ -195,8 +193,8 @@ int __weak kgdb_validate_break_address(unsigned long addr) return err; err = kgdb_arch_remove_breakpoint(&tmp); if (err) - printk(KERN_ERR "KGDB: Critical breakpoint error, kernel " - "memory destroyed at: %lx", addr); + pr_err("Critical breakpoint error, kernel memory destroyed at: %lx\n", + addr); return err; } @@ -204,6 +202,7 @@ unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs) { return instruction_pointer(regs); } +NOKPROBE_SYMBOL(kgdb_arch_pc); int __weak kgdb_arch_init(void) { @@ -214,6 +213,65 @@ int __weak kgdb_skipexception(int exception, struct pt_regs *regs) { return 0; } +NOKPROBE_SYMBOL(kgdb_skipexception); + +#ifdef CONFIG_SMP + +/* + * Default (weak) implementation for kgdb_roundup_cpus + */ + +void __weak kgdb_call_nmi_hook(void *ignored) +{ + /* + * NOTE: get_irq_regs() is supposed to get the registers from + * before the IPI interrupt happened and so is supposed to + * show where the processor was. In some situations it's + * possible we might be called without an IPI, so it might be + * safer to figure out how to make kgdb_breakpoint() work + * properly here. + */ + kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); +} +NOKPROBE_SYMBOL(kgdb_call_nmi_hook); + +static DEFINE_PER_CPU(call_single_data_t, kgdb_roundup_csd) = + CSD_INIT(kgdb_call_nmi_hook, NULL); + +void __weak kgdb_roundup_cpus(void) +{ + call_single_data_t *csd; + int this_cpu = raw_smp_processor_id(); + int cpu; + int ret; + + for_each_online_cpu(cpu) { + /* No need to roundup ourselves */ + if (cpu == this_cpu) + continue; + + csd = &per_cpu(kgdb_roundup_csd, cpu); + + /* + * If it didn't round up last time, don't try again + * since smp_call_function_single_async() will block. + * + * If rounding_up is false then we know that the + * previous call must have at least started and that + * means smp_call_function_single_async() won't block. + */ + if (kgdb_info[cpu].rounding_up) + continue; + kgdb_info[cpu].rounding_up = true; + + ret = smp_call_function_single_async(cpu, csd); + if (ret) + kgdb_info[cpu].rounding_up = false; + } +} +NOKPROBE_SYMBOL(kgdb_roundup_cpus); + +#endif /* * Some architectures need cache flushes when we set/clear a @@ -224,13 +282,10 @@ static void kgdb_flush_swbreak_addr(unsigned long addr) if (!CACHE_FLUSH_IS_SAFE) return; - if (current->mm && current->mm->mmap_cache) { - flush_cache_range(current->mm->mmap_cache, - addr, addr + BREAK_INSTR_SIZE); - } /* Force flush instruction cache if it was outside the mm */ flush_icache_range(addr, addr + BREAK_INSTR_SIZE); } +NOKPROBE_SYMBOL(kgdb_flush_swbreak_addr); /* * SW breakpoint management: @@ -248,8 +303,8 @@ int dbg_activate_sw_breakpoints(void) error = kgdb_arch_set_breakpoint(&kgdb_break[i]); if (error) { ret = error; - printk(KERN_INFO "KGDB: BP install failed: %lx", - kgdb_break[i].bpt_addr); + pr_info("BP install failed: %lx\n", + kgdb_break[i].bpt_addr); continue; } @@ -258,6 +313,7 @@ int dbg_activate_sw_breakpoints(void) } return ret; } +NOKPROBE_SYMBOL(dbg_activate_sw_breakpoints); int dbg_set_sw_break(unsigned long addr) { @@ -311,8 +367,8 @@ int dbg_deactivate_sw_breakpoints(void) continue; error = kgdb_arch_remove_breakpoint(&kgdb_break[i]); if (error) { - printk(KERN_INFO "KGDB: BP remove failed: %lx\n", - kgdb_break[i].bpt_addr); + pr_info("BP remove failed: %lx\n", + kgdb_break[i].bpt_addr); ret = error; } @@ -321,6 +377,7 @@ int dbg_deactivate_sw_breakpoints(void) } return ret; } +NOKPROBE_SYMBOL(dbg_deactivate_sw_breakpoints); int dbg_remove_sw_break(unsigned long addr) { @@ -348,6 +405,18 @@ int kgdb_isremovedbreak(unsigned long addr) return 0; } +int kgdb_has_hit_break(unsigned long addr) +{ + int i; + + for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { + if (kgdb_break[i].state == BP_ACTIVE && + kgdb_break[i].bpt_addr == addr) + return 1; + } + return 0; +} + int dbg_remove_all_break(void) { int error; @@ -359,7 +428,7 @@ int dbg_remove_all_break(void) goto setundefined; error = kgdb_arch_remove_breakpoint(&kgdb_break[i]); if (error) - printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n", + pr_err("breakpoint remove failed: %lx\n", kgdb_break[i].bpt_addr); setundefined: kgdb_break[i].state = BP_UNDEFINED; @@ -372,6 +441,48 @@ setundefined: return 0; } +void kgdb_free_init_mem(void) +{ + int i; + + /* Clear init memory breakpoints. */ + for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { + if (init_section_contains((void *)kgdb_break[i].bpt_addr, 0)) + kgdb_break[i].state = BP_UNDEFINED; + } +} + +#ifdef CONFIG_KGDB_KDB +void kdb_dump_stack_on_cpu(int cpu) +{ + if (cpu == raw_smp_processor_id() || !IS_ENABLED(CONFIG_SMP)) { + dump_stack(); + return; + } + + if (!(kgdb_info[cpu].exception_state & DCPU_IS_SLAVE)) { + kdb_printf("ERROR: Task on cpu %d didn't stop in the debugger\n", + cpu); + return; + } + + /* + * In general, architectures don't support dumping the stack of a + * "running" process that's not the current one. From the point of + * view of the Linux, kernel processes that are looping in the kgdb + * slave loop are still "running". There's also no API (that actually + * works across all architectures) that can do a stack crawl based + * on registers passed as a parameter. + * + * Solve this conundrum by asking slave CPUs to do the backtrace + * themselves. + */ + kgdb_info[cpu].exception_state |= DCPU_WANT_BT; + while (kgdb_info[cpu].exception_state & DCPU_WANT_BT) + cpu_relax(); +} +#endif + /* * Return true if there is a valid kgdb I/O module. Also if no * debugger is attached a message can be printed to the console about @@ -392,13 +503,14 @@ static int kgdb_io_ready(int print_wait) if (print_wait) { #ifdef CONFIG_KGDB_KDB if (!dbg_kdb_mode) - printk(KERN_CRIT "KGDB: waiting... or $3#33 for KDB\n"); + pr_crit("waiting... or $3#33 for KDB\n"); #else - printk(KERN_CRIT "KGDB: Waiting for remote debugger\n"); + pr_crit("Waiting for remote debugger\n"); #endif } return 1; } +NOKPROBE_SYMBOL(kgdb_io_ready); static int kgdb_reenter_check(struct kgdb_state *ks) { @@ -422,8 +534,7 @@ static int kgdb_reenter_check(struct kgdb_state *ks) exception_level = 0; kgdb_skipexception(ks->ex_vector, ks->linux_regs); dbg_activate_sw_breakpoints(); - printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n", - addr); + pr_crit("re-enter error: breakpoint removed %lx\n", addr); WARN_ON_ONCE(1); return 1; @@ -433,10 +544,11 @@ static int kgdb_reenter_check(struct kgdb_state *ks) if (exception_level > 1) { dump_stack(); + kgdb_io_module_registered = false; panic("Recursive entry to debugger"); } - printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n"); + pr_crit("re-enter exception: ALL breakpoints killed\n"); #ifdef CONFIG_KGDB_KDB /* Allow kdb to debug itself one level */ return 0; @@ -446,6 +558,7 @@ static int kgdb_reenter_check(struct kgdb_state *ks) return 1; } +NOKPROBE_SYMBOL(kgdb_reenter_check); static void dbg_touch_watchdogs(void) { @@ -453,6 +566,7 @@ static void dbg_touch_watchdogs(void) clocksource_touch_watchdog(); rcu_cpu_stall_reset(); } +NOKPROBE_SYMBOL(dbg_touch_watchdogs); static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs, int exception_state) @@ -463,6 +577,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs, int cpu; int trace_on = 0; int online_cpus = num_online_cpus(); + u64 time_left; kgdb_info[ks->cpu].enter_kgdb++; kgdb_info[ks->cpu].exception_state |= exception_state; @@ -476,6 +591,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs, arch_kgdb_ops.disable_hw_break(regs); acquirelock: + rcu_read_lock(); /* * Interrupts will be restored by the 'trap return' code, except when * single stepping. @@ -511,6 +627,9 @@ cpu_loop: atomic_xchg(&kgdb_active, cpu); break; } + } else if (kgdb_info[cpu].exception_state & DCPU_WANT_BT) { + dump_stack(); + kgdb_info[cpu].exception_state &= ~DCPU_WANT_BT; } else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) { if (!raw_spin_is_locked(&dbg_slave_lock)) goto return_normal; @@ -523,13 +642,16 @@ return_normal: arch_kgdb_ops.correct_hw_break(); if (trace_on) tracing_on(); + kgdb_info[cpu].debuggerinfo = NULL; + kgdb_info[cpu].task = NULL; kgdb_info[cpu].exception_state &= ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE); kgdb_info[cpu].enter_kgdb--; - smp_mb__before_atomic_dec(); + smp_mb__before_atomic(); atomic_dec(&slaves_in_kgdb); dbg_touch_watchdogs(); local_irq_restore(flags); + rcu_read_unlock(); return 0; } cpu_relax(); @@ -548,6 +670,7 @@ return_normal: raw_spin_unlock(&dbg_master_lock); dbg_touch_watchdogs(); local_irq_restore(flags); + rcu_read_unlock(); goto acquirelock; } @@ -563,6 +686,8 @@ return_normal: if (kgdb_skipexception(ks->ex_vector, ks->linux_regs)) goto kgdb_restore; + atomic_inc(&ignore_console_lock_warning); + /* Call the I/O driver's pre_exception routine */ if (dbg_io_ops->pre_exception) dbg_io_ops->pre_exception(); @@ -575,17 +700,25 @@ return_normal: raw_spin_lock(&dbg_slave_lock); #ifdef CONFIG_SMP + /* If send_ready set, slaves are already waiting */ + if (ks->send_ready) + atomic_set(ks->send_ready, 1); + /* Signal the other CPUs to enter kgdb_wait() */ - if ((!kgdb_single_step) && kgdb_do_roundup) - kgdb_roundup_cpus(flags); + else if ((!kgdb_single_step) && kgdb_do_roundup) + kgdb_roundup_cpus(); #endif /* * Wait for the other CPUs to be notified and be waiting for us: */ - while (kgdb_do_roundup && (atomic_read(&masters_in_kgdb) + - atomic_read(&slaves_in_kgdb)) != online_cpus) - cpu_relax(); + time_left = MSEC_PER_SEC; + while (kgdb_do_roundup && --time_left && + (atomic_read(&masters_in_kgdb) + atomic_read(&slaves_in_kgdb)) != + online_cpus) + udelay(1000); + if (!time_left) + pr_crit("Timed out waiting for secondary CPUs.\n"); /* * At this point the primary processor is completely @@ -608,6 +741,29 @@ cpu_master_loop: continue; kgdb_connected = 0; } else { + /* + * This is a brutal way to interfere with the debugger + * and prevent gdb being used to poke at kernel memory. + * This could cause trouble if lockdown is applied when + * there is already an active gdb session. For now the + * answer is simply "don't do that". Typically lockdown + * *will* be applied before the debug core gets started + * so only developers using kgdb for fairly advanced + * early kernel debug can be biten by this. Hopefully + * they are sophisticated enough to take care of + * themselves, especially with help from the lockdown + * message printed on the console! + */ + if (security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL)) { + if (IS_ENABLED(CONFIG_KGDB_KDB)) { + /* Switch back to kdb if possible... */ + dbg_kdb_mode = 1; + continue; + } else { + /* ... otherwise just bail */ + break; + } + } error = gdb_serial_stub(ks); } @@ -623,10 +779,14 @@ cpu_master_loop: } } + dbg_activate_sw_breakpoints(); + /* Call the I/O driver's post_exception routine */ if (dbg_io_ops->post_exception) dbg_io_ops->post_exception(); + atomic_dec(&ignore_console_lock_warning); + if (!kgdb_single_step) { raw_spin_unlock(&dbg_slave_lock); /* Wait till all the CPUs have quit from the debugger. */ @@ -647,19 +807,23 @@ kgdb_restore: if (trace_on) tracing_on(); + kgdb_info[cpu].debuggerinfo = NULL; + kgdb_info[cpu].task = NULL; kgdb_info[cpu].exception_state &= ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE); kgdb_info[cpu].enter_kgdb--; - smp_mb__before_atomic_dec(); + smp_mb__before_atomic(); atomic_dec(&masters_in_kgdb); /* Free kgdb_active */ atomic_set(&kgdb_active, -1); raw_spin_unlock(&dbg_master_lock); dbg_touch_watchdogs(); local_irq_restore(flags); + rcu_read_unlock(); return kgdb_info[cpu].ret_state; } +NOKPROBE_SYMBOL(kgdb_cpu_enter); /* * kgdb_handle_exception() - main entry point from a kernel exception @@ -673,36 +837,34 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs) { struct kgdb_state kgdb_var; struct kgdb_state *ks = &kgdb_var; - int ret = 0; - - if (arch_kgdb_ops.enable_nmi) - arch_kgdb_ops.enable_nmi(0); + /* + * Avoid entering the debugger if we were triggered due to an oops + * but panic_timeout indicates the system should automatically + * reboot on panic. We don't want to get stuck waiting for input + * on such systems, especially if its "just" an oops. + */ + if (signo != SIGTRAP && panic_timeout) + return 1; + memset(ks, 0, sizeof(struct kgdb_state)); ks->cpu = raw_smp_processor_id(); ks->ex_vector = evector; ks->signo = signo; ks->err_code = ecode; - ks->kgdb_usethreadid = 0; ks->linux_regs = regs; if (kgdb_reenter_check(ks)) - goto out; /* Ouch, double exception ! */ + return 0; /* Ouch, double exception ! */ if (kgdb_info[ks->cpu].enter_kgdb != 0) - goto out; + return 0; - ret = kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER); -out: - if (arch_kgdb_ops.enable_nmi) - arch_kgdb_ops.enable_nmi(1); - return ret; + return kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER); } +NOKPROBE_SYMBOL(kgdb_handle_exception); /* - * GDB places a breakpoint at this function to know dynamically - * loaded objects. It's not defined static so that only one instance with this - * name exists in the kernel. + * GDB places a breakpoint at this function to know dynamically loaded objects. */ - static int module_event(struct notifier_block *self, unsigned long val, void *data) { @@ -719,6 +881,8 @@ int kgdb_nmicallback(int cpu, void *regs) struct kgdb_state kgdb_var; struct kgdb_state *ks = &kgdb_var; + kgdb_info[cpu].rounding_up = false; + memset(ks, 0, sizeof(struct kgdb_state)); ks->cpu = cpu; ks->linux_regs = regs; @@ -731,6 +895,33 @@ int kgdb_nmicallback(int cpu, void *regs) #endif return 1; } +NOKPROBE_SYMBOL(kgdb_nmicallback); + +int kgdb_nmicallin(int cpu, int trapnr, void *regs, int err_code, + atomic_t *send_ready) +{ +#ifdef CONFIG_SMP + if (!kgdb_io_ready(0) || !send_ready) + return 1; + + if (kgdb_info[cpu].enter_kgdb == 0) { + struct kgdb_state kgdb_var; + struct kgdb_state *ks = &kgdb_var; + + memset(ks, 0, sizeof(struct kgdb_state)); + ks->cpu = cpu; + ks->ex_vector = trapnr; + ks->signo = SIGTRAP; + ks->err_code = err_code; + ks->linux_regs = regs; + ks->send_ready = send_ready; + kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER); + return 0; + } +#endif + return 1; +} +NOKPROBE_SYMBOL(kgdb_nmicallin); static void kgdb_console_write(struct console *co, const char *s, unsigned count) @@ -754,46 +945,75 @@ static struct console kgdbcons = { .index = -1, }; +static int __init opt_kgdb_con(char *str) +{ + kgdb_use_con = 1; + + if (kgdb_io_module_registered && !kgdb_con_registered) { + register_console(&kgdbcons); + kgdb_con_registered = 1; + } + + return 0; +} + +early_param("kgdbcon", opt_kgdb_con); + #ifdef CONFIG_MAGIC_SYSRQ -static void sysrq_handle_dbg(int key) +static void sysrq_handle_dbg(u8 key) { if (!dbg_io_ops) { - printk(KERN_CRIT "ERROR: No KGDB I/O module available\n"); + pr_crit("ERROR: No KGDB I/O module available\n"); return; } if (!kgdb_connected) { #ifdef CONFIG_KGDB_KDB if (!dbg_kdb_mode) - printk(KERN_CRIT "KGDB or $3#33 for KDB\n"); + pr_crit("KGDB or $3#33 for KDB\n"); #else - printk(KERN_CRIT "Entering KGDB\n"); + pr_crit("Entering KGDB\n"); #endif } kgdb_breakpoint(); } -static struct sysrq_key_op sysrq_dbg_op = { +static const struct sysrq_key_op sysrq_dbg_op = { .handler = sysrq_handle_dbg, .help_msg = "debug(g)", .action_msg = "DEBUG", }; #endif -static int kgdb_panic_event(struct notifier_block *self, - unsigned long val, - void *data) +void kgdb_panic(const char *msg) { + if (!kgdb_io_module_registered) + return; + + /* + * We don't want to get stuck waiting for input from user if + * "panic_timeout" indicates the system should automatically + * reboot on panic. + */ + if (panic_timeout) + return; + + debug_locks_off(); + console_flush_on_panic(CONSOLE_FLUSH_PENDING); + if (dbg_kdb_mode) - kdb_printf("PANIC: %s\n", (char *)data); + kdb_printf("PANIC: %s\n", msg); + kgdb_breakpoint(); - return NOTIFY_DONE; } -static struct notifier_block kgdb_panic_event_nb = { - .notifier_call = kgdb_panic_event, - .priority = INT_MAX, -}; +static void kgdb_initial_breakpoint(void) +{ + kgdb_break_asap = 0; + + pr_crit("Waiting for connection from remote gdb...\n"); + kgdb_breakpoint(); +} void __weak kgdb_arch_late(void) { @@ -805,6 +1025,9 @@ void __init dbg_late_init(void) if (kgdb_io_module_registered) kgdb_arch_late(); kdb_init(KDB_INIT_FULL); + + if (kgdb_io_module_registered && kgdb_break_asap) + kgdb_initial_breakpoint(); } static int @@ -813,12 +1036,13 @@ dbg_notify_reboot(struct notifier_block *this, unsigned long code, void *x) /* * Take the following action on reboot notify depending on value: * 1 == Enter debugger - * 0 == [the default] detatch debug client + * 0 == [the default] detach debug client * -1 == Do nothing... and use this until the board resets */ switch (kgdbreboot) { case 1: kgdb_breakpoint(); + goto done; case -1: goto done; } @@ -843,8 +1067,6 @@ static void kgdb_register_callbacks(void) kgdb_arch_late(); register_module_notifier(&dbg_module_load_nb); register_reboot_notifier(&dbg_reboot_notifier); - atomic_notifier_chain_register(&panic_notifier_list, - &kgdb_panic_event_nb); #ifdef CONFIG_MAGIC_SYSRQ register_sysrq_key('g', &sysrq_dbg_op); #endif @@ -858,16 +1080,14 @@ static void kgdb_register_callbacks(void) static void kgdb_unregister_callbacks(void) { /* - * When this routine is called KGDB should unregister from the - * panic handler and clean up, making sure it is not handling any + * When this routine is called KGDB should unregister from + * handlers and clean up, making sure it is not handling any * break exceptions at the time. */ if (kgdb_io_module_registered) { kgdb_io_module_registered = 0; unregister_reboot_notifier(&dbg_reboot_notifier); unregister_module_notifier(&dbg_module_load_nb); - atomic_notifier_chain_unregister(&panic_notifier_list, - &kgdb_panic_event_nb); kgdb_arch_exit(); #ifdef CONFIG_MAGIC_SYSRQ unregister_sysrq_key('g', &sysrq_dbg_op); @@ -879,39 +1099,6 @@ static void kgdb_unregister_callbacks(void) } } -/* - * There are times a tasklet needs to be used vs a compiled in - * break point so as to cause an exception outside a kgdb I/O module, - * such as is the case with kgdboe, where calling a breakpoint in the - * I/O driver itself would be fatal. - */ -static void kgdb_tasklet_bpt(unsigned long ing) -{ - kgdb_breakpoint(); - atomic_set(&kgdb_break_tasklet_var, 0); -} - -static DECLARE_TASKLET(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt, 0); - -void kgdb_schedule_breakpoint(void) -{ - if (atomic_read(&kgdb_break_tasklet_var) || - atomic_read(&kgdb_active) != -1 || - atomic_read(&kgdb_setting_breakpoint)) - return; - atomic_inc(&kgdb_break_tasklet_var); - tasklet_schedule(&kgdb_tasklet_breakpoint); -} -EXPORT_SYMBOL_GPL(kgdb_schedule_breakpoint); - -static void kgdb_initial_breakpoint(void) -{ - kgdb_break_asap = 0; - - printk(KERN_CRIT "kgdb: Waiting for connection from remote gdb...\n"); - kgdb_breakpoint(); -} - /** * kgdb_register_io_module - register KGDB IO module * @new_dbg_io_ops: the io ops vector @@ -920,16 +1107,22 @@ static void kgdb_initial_breakpoint(void) */ int kgdb_register_io_module(struct kgdb_io *new_dbg_io_ops) { + struct kgdb_io *old_dbg_io_ops; int err; spin_lock(&kgdb_registration_lock); - if (dbg_io_ops) { - spin_unlock(&kgdb_registration_lock); + old_dbg_io_ops = dbg_io_ops; + if (old_dbg_io_ops) { + if (!old_dbg_io_ops->deinit) { + spin_unlock(&kgdb_registration_lock); - printk(KERN_ERR "kgdb: Another I/O driver is already " - "registered with KGDB.\n"); - return -EBUSY; + pr_err("KGDB I/O driver %s can't replace %s.\n", + new_dbg_io_ops->name, old_dbg_io_ops->name); + return -EBUSY; + } + pr_info("Replacing I/O driver %s with %s\n", + old_dbg_io_ops->name, new_dbg_io_ops->name); } if (new_dbg_io_ops->init) { @@ -944,13 +1137,18 @@ int kgdb_register_io_module(struct kgdb_io *new_dbg_io_ops) spin_unlock(&kgdb_registration_lock); - printk(KERN_INFO "kgdb: Registered I/O driver %s.\n", - new_dbg_io_ops->name); + if (old_dbg_io_ops) { + old_dbg_io_ops->deinit(); + return 0; + } + + pr_info("Registered I/O driver %s\n", new_dbg_io_ops->name); /* Arm KGDB now. */ kgdb_register_callbacks(); - if (kgdb_break_asap) + if (kgdb_break_asap && + (!dbg_is_early || IS_ENABLED(CONFIG_ARCH_HAS_EARLY_DEBUG))) kgdb_initial_breakpoint(); return 0; @@ -958,7 +1156,7 @@ int kgdb_register_io_module(struct kgdb_io *new_dbg_io_ops) EXPORT_SYMBOL_GPL(kgdb_register_io_module); /** - * kkgdb_unregister_io_module - unregister KGDB IO module + * kgdb_unregister_io_module - unregister KGDB IO module * @old_dbg_io_ops: the io ops vector * * Unregister it with the KGDB core. @@ -980,8 +1178,10 @@ void kgdb_unregister_io_module(struct kgdb_io *old_dbg_io_ops) spin_unlock(&kgdb_registration_lock); - printk(KERN_INFO - "kgdb: Unregistered I/O driver %s, debugger disabled.\n", + if (old_dbg_io_ops->deinit) + old_dbg_io_ops->deinit(); + + pr_info("Unregistered I/O driver %s, debugger disabled\n", old_dbg_io_ops->name); } EXPORT_SYMBOL_GPL(kgdb_unregister_io_module); @@ -1006,7 +1206,7 @@ int dbg_io_get_char(void) * otherwise as a quick means to stop program execution and "break" into * the debugger. */ -void kgdb_breakpoint(void) +noinline void kgdb_breakpoint(void) { atomic_inc(&kgdb_setting_breakpoint); wmb(); /* Sync point before breakpoint */ @@ -1021,7 +1221,8 @@ static int __init opt_kgdb_wait(char *str) kgdb_break_asap = 1; kdb_init(KDB_INIT_EARLY); - if (kgdb_io_module_registered) + if (kgdb_io_module_registered && + IS_ENABLED(CONFIG_ARCH_HAS_EARLY_DEBUG)) kgdb_initial_breakpoint(); return 0; diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h index 2235967e78b0..cd22b5f68831 100644 --- a/kernel/debug/debug_core.h +++ b/kernel/debug/debug_core.h @@ -26,13 +26,14 @@ struct kgdb_state { unsigned long threadid; long kgdb_usethreadid; struct pt_regs *linux_regs; + atomic_t *send_ready; }; /* Exception state values */ #define DCPU_WANT_MASTER 0x1 /* Waiting to become a master kgdb cpu */ #define DCPU_NEXT_MASTER 0x2 /* Transition from one master cpu to another */ #define DCPU_IS_SLAVE 0x4 /* Slave cpu enter exception */ -#define DCPU_SSTEP 0x8 /* CPU is single stepping */ +#define DCPU_WANT_BT 0x8 /* Slave cpu should backtrace then clear flag */ struct debuggerinfo_struct { void *debuggerinfo; @@ -41,6 +42,7 @@ struct debuggerinfo_struct { int ret_state; int irq_depth; int enter_kgdb; + bool rounding_up; }; extern struct debuggerinfo_struct kgdb_info[]; @@ -74,6 +76,7 @@ extern int kdb_stub(struct kgdb_state *ks); extern int kdb_parse(const char *cmdstr); extern int kdb_common_init_state(struct kgdb_state *ks); extern int kdb_common_deinit_state(void); +extern void kdb_dump_stack_on_cpu(int cpu); #else /* ! CONFIG_KGDB_KDB */ static inline int kdb_stub(struct kgdb_state *ks) { diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c index 19d9a578c753..22fe969c5d2e 100644 --- a/kernel/debug/gdbstub.c +++ b/kernel/debug/gdbstub.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Kernel Debug Core * @@ -22,20 +23,18 @@ * * Original KGDB stub: David Grothe <dave@gcom.com>, * Tigran Aivazian <tigran@sco.com> - * - * This file is licensed under the terms of the GNU General Public License - * version 2. This program is licensed "as is" without any warranty of any - * kind, whether express or implied. */ #include <linux/kernel.h> +#include <linux/sched/signal.h> #include <linux/kgdb.h> #include <linux/kdb.h> #include <linux/serial_core.h> +#include <linux/string.h> #include <linux/reboot.h> #include <linux/uaccess.h> #include <asm/cacheflush.h> -#include <asm/unaligned.h> +#include <linux/unaligned.h> #include "debug_core.h" #define KGDB_MAX_THREAD_QUERY 17 @@ -246,7 +245,7 @@ char *kgdb_mem2hex(char *mem, char *buf, int count) */ tmp = buf + count; - err = probe_kernel_read(tmp, mem, count); + err = copy_from_kernel_nofault(tmp, mem, count); if (err) return NULL; while (count > 0) { @@ -282,7 +281,7 @@ int kgdb_hex2mem(char *buf, char *mem, int count) *tmp_raw |= hex_to_bin(*tmp_hex--) << 4; } - return probe_kernel_write(mem, tmp_raw, count); + return copy_to_kernel_nofault(mem, tmp_raw, count); } /* @@ -320,7 +319,7 @@ int kgdb_hex2long(char **ptr, unsigned long *long_val) /* * Copy the binary array pointed to by buf into mem. Fix $, #, and * 0x7d escaped with 0x7d. Return -EFAULT on failure or 0 on success. - * The input buf is overwitten with the result to write to mem. + * The input buf is overwritten with the result to write to mem. */ static int kgdb_ebin2mem(char *buf, char *mem, int count) { @@ -334,7 +333,7 @@ static int kgdb_ebin2mem(char *buf, char *mem, int count) size++; } - return probe_kernel_write(mem, c, size); + return copy_to_kernel_nofault(mem, c, size); } #if DBG_MAX_REG_NUM > 0 @@ -549,7 +548,7 @@ static void gdb_cmd_setregs(struct kgdb_state *ks) error_packet(remcom_out_buffer, -EINVAL); } else { gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs); - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); } } @@ -579,7 +578,7 @@ static void gdb_cmd_memwrite(struct kgdb_state *ks) if (err) error_packet(remcom_out_buffer, err); else - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); } #if DBG_MAX_REG_NUM > 0 @@ -594,7 +593,7 @@ static char *gdb_hex_reg_helper(int regnum, char *out) dbg_reg_def[i].size); } -/* Handle the 'p' individual regster get */ +/* Handle the 'p' individual register get */ static void gdb_cmd_reg_get(struct kgdb_state *ks) { unsigned long regnum; @@ -609,7 +608,7 @@ static void gdb_cmd_reg_get(struct kgdb_state *ks) gdb_hex_reg_helper(regnum, remcom_out_buffer); } -/* Handle the 'P' individual regster set */ +/* Handle the 'P' individual register set */ static void gdb_cmd_reg_set(struct kgdb_state *ks) { unsigned long regnum; @@ -632,7 +631,7 @@ static void gdb_cmd_reg_set(struct kgdb_state *ks) i = i / 2; kgdb_hex2mem(ptr, (char *)gdb_regs, i); dbg_set_reg(regnum, gdb_regs, ks->linux_regs); - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); } #endif /* DBG_MAX_REG_NUM > 0 */ @@ -644,7 +643,7 @@ static void gdb_cmd_binwrite(struct kgdb_state *ks) if (err) error_packet(remcom_out_buffer, err); else - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); } /* Handle the 'D' or 'k', detach or kill packets */ @@ -658,7 +657,7 @@ static void gdb_cmd_detachkill(struct kgdb_state *ks) if (error < 0) { error_packet(remcom_out_buffer, error); } else { - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); kgdb_connected = 0; } put_packet(remcom_out_buffer); @@ -678,7 +677,7 @@ static int gdb_cmd_reboot(struct kgdb_state *ks) /* For now, only honor R0 */ if (strcmp(remcom_in_buffer, "R0") == 0) { printk(KERN_CRIT "Executing emergency reboot\n"); - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); put_packet(remcom_out_buffer); /* @@ -724,7 +723,7 @@ static void gdb_cmd_query(struct kgdb_state *ks) } } - do_each_thread(g, p) { + for_each_process_thread(g, p) { if (i >= ks->thr_query && !finished) { int_to_threadref(thref, p->pid); ptr = pack_threadid(ptr, thref); @@ -734,14 +733,14 @@ static void gdb_cmd_query(struct kgdb_state *ks) finished = 1; } i++; - } while_each_thread(g, p); + } *(--ptr) = '\0'; break; case 'C': /* Current thread id */ - strcpy(remcom_out_buffer, "QC"); + strscpy(remcom_out_buffer, "QC"); ks->threadid = shadow_pid(current->pid); int_to_threadref(thref, ks->threadid); pack_threadid(remcom_out_buffer + 2, thref); @@ -775,7 +774,7 @@ static void gdb_cmd_query(struct kgdb_state *ks) int len = strlen(remcom_in_buffer + 6); if ((len % 2) != 0) { - strcpy(remcom_out_buffer, "E01"); + strscpy(remcom_out_buffer, "E01"); break; } kgdb_hex2mem(remcom_in_buffer + 6, @@ -787,10 +786,23 @@ static void gdb_cmd_query(struct kgdb_state *ks) kdb_parse(remcom_out_buffer); kdb_common_deinit_state(); - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); } break; #endif +#ifdef CONFIG_HAVE_ARCH_KGDB_QXFER_PKT + case 'S': + if (!strncmp(remcom_in_buffer, "qSupported:", 11)) + strscpy(remcom_out_buffer, kgdb_arch_gdb_stub_feature); + break; + case 'X': + if (!strncmp(remcom_in_buffer, "qXfer:", 6)) + kgdb_arch_handle_qxfer_pkt(remcom_in_buffer, + remcom_out_buffer); + break; +#endif + default: + break; } } @@ -811,7 +823,7 @@ static void gdb_cmd_task(struct kgdb_state *ks) } kgdb_usethread = thread; ks->kgdb_usethreadid = ks->threadid; - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); break; case 'c': ptr = &remcom_in_buffer[2]; @@ -826,7 +838,7 @@ static void gdb_cmd_task(struct kgdb_state *ks) } kgdb_contthread = thread; } - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); break; } } @@ -840,7 +852,7 @@ static void gdb_cmd_thread(struct kgdb_state *ks) kgdb_hex2long(&ptr, &ks->threadid); thread = getthread(ks->linux_regs, ks->threadid); if (thread) - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); else error_packet(remcom_out_buffer, -EINVAL); } @@ -902,7 +914,7 @@ static void gdb_cmd_break(struct kgdb_state *ks) (int) length, *bpt_type - '0'); if (error == 0) - strcpy(remcom_out_buffer, "OK"); + strscpy(remcom_out_buffer, "OK"); else error_packet(remcom_out_buffer, error); } @@ -938,7 +950,7 @@ static int gdb_cmd_exception_pass(struct kgdb_state *ks) } /* - * This function performs all gdbserial command procesing + * This function performs all gdbserial command processing */ int gdb_serial_stub(struct kgdb_state *ks) { @@ -1031,6 +1043,7 @@ int gdb_serial_stub(struct kgdb_state *ks) gdb_cmd_detachkill(ks); return DBG_PASS_EVENT; } + fallthrough; #endif case 'C': /* Exception passing */ tmp = gdb_cmd_exception_pass(ks); @@ -1038,7 +1051,7 @@ int gdb_serial_stub(struct kgdb_state *ks) goto default_handle; if (tmp == 0) break; - /* Fall through on tmp < 0 */ + fallthrough; /* on tmp < 0 */ case 'c': /* Continue packet */ case 's': /* Single step packet */ if (kgdb_contthread && kgdb_contthread != current) { @@ -1046,8 +1059,7 @@ int gdb_serial_stub(struct kgdb_state *ks) error_packet(remcom_out_buffer, -EINVAL); break; } - dbg_activate_sw_breakpoints(); - /* Fall through to default processing */ + fallthrough; /* to default processing */ default: default_handle: error = kgdb_arch_handle_exception(ks->ex_vector, @@ -1093,10 +1105,10 @@ int gdbstub_state(struct kgdb_state *ks, char *cmd) return error; case 's': case 'c': - strcpy(remcom_in_buffer, cmd); + strscpy(remcom_in_buffer, cmd, sizeof(remcom_in_buffer)); return 0; case '$': - strcpy(remcom_in_buffer, cmd); + strscpy(remcom_in_buffer, cmd, sizeof(remcom_in_buffer)); gdbstub_use_prev_in_buf = strlen(remcom_in_buffer); gdbstub_prev_in_buf_pos = 0; return 0; diff --git a/kernel/debug/kdb/.gitignore b/kernel/debug/kdb/.gitignore index 396d12eda9e8..df259542a236 100644 --- a/kernel/debug/kdb/.gitignore +++ b/kernel/debug/kdb/.gitignore @@ -1 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only gen-kdb_cmds.c diff --git a/kernel/debug/kdb/Makefile b/kernel/debug/kdb/Makefile index d4fc58f4b88d..efac857c5511 100644 --- a/kernel/debug/kdb/Makefile +++ b/kernel/debug/kdb/Makefile @@ -6,7 +6,6 @@ # Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. # -CCVERSION := $(shell $(CC) -v 2>&1 | sed -ne '$$p') obj-y := kdb_io.o kdb_main.o kdb_support.o kdb_bt.o gen-kdb_cmds.o kdb_bp.o kdb_debugger.o obj-$(CONFIG_KDB_KEYBOARD) += kdb_keyboard.o diff --git a/kernel/debug/kdb/kdb_bp.c b/kernel/debug/kdb/kdb_bp.c index 70a504601dc3..c0c2072f5452 100644 --- a/kernel/debug/kdb/kdb_bp.c +++ b/kernel/debug/kdb/kdb_bp.c @@ -52,11 +52,11 @@ static int kdb_parsebp(int argc, const char **argv, int *nextargp, kdb_bp_t *bp) bp->bph_length = 1; if ((argc + 1) != nextarg) { - if (strnicmp(argv[nextarg], "datar", sizeof("datar")) == 0) + if (strncasecmp(argv[nextarg], "datar", sizeof("datar")) == 0) bp->bp_type = BP_ACCESS_WATCHPOINT; - else if (strnicmp(argv[nextarg], "dataw", sizeof("dataw")) == 0) + else if (strncasecmp(argv[nextarg], "dataw", sizeof("dataw")) == 0) bp->bp_type = BP_WRITE_WATCHPOINT; - else if (strnicmp(argv[nextarg], "inst", sizeof("inst")) == 0) + else if (strncasecmp(argv[nextarg], "inst", sizeof("inst")) == 0) bp->bp_type = BP_HARDWARE_BREAKPOINT; else return KDB_ARGCOUNT; @@ -153,13 +153,11 @@ static int _kdb_bp_install(struct pt_regs *regs, kdb_bp_t *bp) } else { kdb_printf("%s: failed to set breakpoint at 0x%lx\n", __func__, bp->bp_addr); -#ifdef CONFIG_DEBUG_RODATA if (!bp->bp_type) { kdb_printf("Software breakpoints are unavailable.\n" - " Change the kernel CONFIG_DEBUG_RODATA=n\n" + " Boot the kernel with rodata=off\n" " OR use hw breaks: help bph\n"); } -#endif return 1; } return 0; @@ -244,11 +242,11 @@ static void kdb_printbp(kdb_bp_t *bp, int i) kdb_symbol_print(bp->bp_addr, NULL, KDB_SP_DEFAULT); if (bp->bp_enabled) - kdb_printf("\n is enabled"); + kdb_printf("\n is enabled "); else kdb_printf("\n is disabled"); - kdb_printf("\taddr at %016lx, hardtype=%d installed=%d\n", + kdb_printf(" addr at %016lx, hardtype=%d installed=%d\n", bp->bp_addr, bp->bp_type, bp->bp_installed); kdb_printf("\n"); @@ -309,6 +307,15 @@ static int kdb_bp(int argc, const char **argv) return KDB_BADINT; /* + * This check is redundant (since the breakpoint machinery should + * be doing the same check during kdb_bp_install) but gives the + * user immediate feedback. + */ + diag = kgdb_validate_break_address(template.bp_addr); + if (diag) + return diag; + + /* * Find an empty bp structure to allocate */ for (bpno = 0, bp = kdb_breakpoints; bpno < KDB_MAXBPT; bpno++, bp++) { @@ -414,7 +421,6 @@ static int kdb_bc(int argc, const char **argv) * assume that the breakpoint number is desired. */ if (addr < KDB_MAXBPT) { - bp = &kdb_breakpoints[addr]; lowbp = highbp = addr; highbp++; } else { @@ -454,13 +460,15 @@ static int kdb_bc(int argc, const char **argv) break; case KDBCMD_BE: + if (bp->bp_enabled) + break; + bp->bp_enabled = 1; kdb_printf("Breakpoint %d at " - kdb_bfd_vma_fmt " enabled", + kdb_bfd_vma_fmt " enabled\n", i, bp->bp_addr); - kdb_printf("\n"); break; case KDBCMD_BD: if (!bp->bp_enabled) @@ -516,6 +524,54 @@ static int kdb_ss(int argc, const char **argv) return KDB_CMD_SS; } +static kdbtab_t bptab[] = { + { .name = "bp", + .func = kdb_bp, + .usage = "[<vaddr>]", + .help = "Set/Display breakpoints", + .flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS, + }, + { .name = "bl", + .func = kdb_bp, + .usage = "[<vaddr>]", + .help = "Display breakpoints", + .flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS, + }, + { .name = "bc", + .func = kdb_bc, + .usage = "<bpnum>", + .help = "Clear Breakpoint", + .flags = KDB_ENABLE_FLOW_CTRL, + }, + { .name = "be", + .func = kdb_bc, + .usage = "<bpnum>", + .help = "Enable Breakpoint", + .flags = KDB_ENABLE_FLOW_CTRL, + }, + { .name = "bd", + .func = kdb_bc, + .usage = "<bpnum>", + .help = "Disable Breakpoint", + .flags = KDB_ENABLE_FLOW_CTRL, + }, + { .name = "ss", + .func = kdb_ss, + .usage = "", + .help = "Single Step", + .minlen = 1, + .flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS, + }, +}; + +static kdbtab_t bphcmd = { + .name = "bph", + .func = kdb_bp, + .usage = "[<vaddr>]", + .help = "[datar [length]|dataw [length]] Set hw brk", + .flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS, +}; + /* Initialize the breakpoint table and register breakpoint commands. */ void __init kdb_initbptab(void) @@ -531,23 +587,7 @@ void __init kdb_initbptab(void) for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) bp->bp_free = 1; - kdb_register_repeat("bp", kdb_bp, "[<vaddr>]", - "Set/Display breakpoints", 0, KDB_REPEAT_NO_ARGS); - kdb_register_repeat("bl", kdb_bp, "[<vaddr>]", - "Display breakpoints", 0, KDB_REPEAT_NO_ARGS); + kdb_register_table(bptab, ARRAY_SIZE(bptab)); if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) - kdb_register_repeat("bph", kdb_bp, "[<vaddr>]", - "[datar [length]|dataw [length]] Set hw brk", 0, KDB_REPEAT_NO_ARGS); - kdb_register_repeat("bc", kdb_bc, "<bpnum>", - "Clear Breakpoint", 0, KDB_REPEAT_NONE); - kdb_register_repeat("be", kdb_bc, "<bpnum>", - "Enable Breakpoint", 0, KDB_REPEAT_NONE); - kdb_register_repeat("bd", kdb_bc, "<bpnum>", - "Disable Breakpoint", 0, KDB_REPEAT_NONE); - - kdb_register_repeat("ss", kdb_ss, "", - "Single Step", 1, KDB_REPEAT_NO_ARGS); - /* - * Architecture dependent initialization. - */ + kdb_register_table(&bphcmd, 1); } diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c index b03e0e814e43..137ba73f56fc 100644 --- a/kernel/debug/kdb/kdb_bt.c +++ b/kernel/debug/kdb/kdb_bt.c @@ -12,7 +12,8 @@ #include <linux/ctype.h> #include <linux/string.h> #include <linux/kernel.h> -#include <linux/sched.h> +#include <linux/sched/signal.h> +#include <linux/sched/debug.h> #include <linux/kdb.h> #include <linux/nmi.h> #include "kdb_private.h" @@ -20,22 +21,18 @@ static void kdb_show_stack(struct task_struct *p, void *addr) { - int old_lvl = console_loglevel; - console_loglevel = 15; kdb_trap_printk++; - kdb_set_current_task(p); - if (addr) { - show_stack((struct task_struct *)p, addr); - } else if (kdb_current_regs) { -#ifdef CONFIG_X86 - show_stack(p, &kdb_current_regs->sp); -#else - show_stack(p, NULL); -#endif + + if (!addr && kdb_task_has_cpu(p)) { + int old_lvl = console_loglevel; + + console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH; + kdb_dump_stack_on_cpu(kdb_process_cpu(p)); + console_loglevel = old_lvl; } else { - show_stack(p, NULL); + show_stack(p, addr, KERN_EMERG); } - console_loglevel = old_lvl; + kdb_trap_printk--; } @@ -49,7 +46,7 @@ static void kdb_show_stack(struct task_struct *p, void *addr) * btp <pid> Kernel stack for <pid> * btt <address-expression> Kernel stack for task structure at * <address-expression> - * bta [DRSTCZEUIMA] All useful processes, optionally + * bta [state_chars>|A] All useful processes, optionally * filtered by state * btc [<cpu>] The current process on one cpu, * default is all cpus @@ -77,12 +74,12 @@ static void kdb_show_stack(struct task_struct *p, void *addr) */ static int -kdb_bt1(struct task_struct *p, unsigned long mask, - int argcount, int btaprompt) +kdb_bt1(struct task_struct *p, const char *mask, bool btaprompt) { - char buffer[2]; - if (kdb_getarea(buffer[0], (unsigned long)p) || - kdb_getarea(buffer[0], (unsigned long)(p+1)-1)) + char ch; + + if (kdb_getarea(ch, (unsigned long)p) || + kdb_getarea(ch, (unsigned long)(p+1)-1)) return KDB_BADADDR; if (!kdb_task_state(p, mask)) return 0; @@ -90,22 +87,46 @@ kdb_bt1(struct task_struct *p, unsigned long mask, kdb_ps1(p); kdb_show_stack(p, NULL); if (btaprompt) { - kdb_getstr(buffer, sizeof(buffer), - "Enter <q> to end, <cr> to continue:"); - if (buffer[0] == 'q') { - kdb_printf("\n"); + kdb_printf("Enter <q> to end, <cr> or <space> to continue:"); + do { + ch = kdb_getchar(); + } while (!strchr("\r\n q", ch)); + kdb_printf("\n"); + + /* reset the pager */ + kdb_nextline = 1; + + if (ch == 'q') return 1; - } } touch_nmi_watchdog(); return 0; } +static void +kdb_bt_cpu(unsigned long cpu) +{ + struct task_struct *kdb_tsk; + + if (cpu >= num_possible_cpus() || !cpu_online(cpu)) { + kdb_printf("WARNING: no process for cpu %ld\n", cpu); + return; + } + + /* If a CPU failed to round up we could be here */ + kdb_tsk = KDB_TSK(cpu); + if (!kdb_tsk) { + kdb_printf("WARNING: no task for cpu %ld\n", cpu); + return; + } + + kdb_bt1(kdb_tsk, "A", false); +} + int kdb_bt(int argc, const char **argv) { int diag; - int argcount = 5; int btaprompt = 1; int nextarg; unsigned long addr; @@ -117,25 +138,25 @@ kdb_bt(int argc, const char **argv) if (strcmp(argv[0], "bta") == 0) { struct task_struct *g, *p; unsigned long cpu; - unsigned long mask = kdb_task_state_string(argc ? argv[1] : - NULL); + const char *mask = argc ? argv[1] : kdbgetenv("PS"); + if (argc == 0) kdb_ps_suppressed(); /* Run the active tasks first */ for_each_online_cpu(cpu) { - p = kdb_curr_task(cpu); - if (kdb_bt1(p, mask, argcount, btaprompt)) + p = curr_task(cpu); + if (kdb_bt1(p, mask, btaprompt)) return 0; } /* Now the inactive tasks */ - kdb_do_each_thread(g, p) { + for_each_process_thread(g, p) { if (KDB_FLAG(CMD_INTERRUPT)) return 0; if (task_curr(p)) continue; - if (kdb_bt1(p, mask, argcount, btaprompt)) + if (kdb_bt1(p, mask, btaprompt)) return 0; - } kdb_while_each_thread(g, p); + } } else if (strcmp(argv[0], "btp") == 0) { struct task_struct *p; unsigned long pid; @@ -145,10 +166,8 @@ kdb_bt(int argc, const char **argv) if (diag) return diag; p = find_task_by_pid_ns(pid, &init_pid_ns); - if (p) { - kdb_set_current_task(p); - return kdb_bt1(p, ~0UL, argcount, 0); - } + if (p) + return kdb_bt1(p, "A", false); kdb_printf("No process with pid == %ld found\n", pid); return 0; } else if (strcmp(argv[0], "btt") == 0) { @@ -157,12 +176,9 @@ kdb_bt(int argc, const char **argv) diag = kdbgetularg((char *)argv[1], &addr); if (diag) return diag; - kdb_set_current_task((struct task_struct *)addr); - return kdb_bt1((struct task_struct *)addr, ~0UL, argcount, 0); + return kdb_bt1((struct task_struct *)addr, "A", false); } else if (strcmp(argv[0], "btc") == 0) { unsigned long cpu = ~0; - struct task_struct *save_current_task = kdb_current_task; - char buf[80]; if (argc > 1) return KDB_ARGCOUNT; if (argc == 1) { @@ -170,26 +186,21 @@ kdb_bt(int argc, const char **argv) if (diag) return diag; } - /* Recursive use of kdb_parse, do not use argv after - * this point */ - argv = NULL; if (cpu != ~0) { - if (cpu >= num_possible_cpus() || !cpu_online(cpu)) { - kdb_printf("no process for cpu %ld\n", cpu); - return 0; + kdb_bt_cpu(cpu); + } else { + /* + * Recursive use of kdb_parse, do not use argv after + * this point. + */ + argv = NULL; + kdb_printf("btc: cpu status: "); + kdb_parse("cpu\n"); + for_each_online_cpu(cpu) { + kdb_bt_cpu(cpu); + touch_nmi_watchdog(); } - sprintf(buf, "btt 0x%p\n", KDB_TSK(cpu)); - kdb_parse(buf); - return 0; - } - kdb_printf("btc: cpu status: "); - kdb_parse("cpu\n"); - for_each_online_cpu(cpu) { - sprintf(buf, "btt 0x%p\n", KDB_TSK(cpu)); - kdb_parse(buf); - touch_nmi_watchdog(); } - kdb_set_current_task(save_current_task); return 0; } else { if (argc) { @@ -201,7 +212,7 @@ kdb_bt(int argc, const char **argv) kdb_show_stack(kdb_current_task, (void *)addr); return 0; } else { - return kdb_bt1(kdb_current_task, ~0UL, argcount, 0); + return kdb_bt1(kdb_current_task, "A", false); } } diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c index 328d18ef31e4..e91fc3e4edd5 100644 --- a/kernel/debug/kdb/kdb_debugger.c +++ b/kernel/debug/kdb/kdb_debugger.c @@ -69,7 +69,10 @@ int kdb_stub(struct kgdb_state *ks) if (atomic_read(&kgdb_setting_breakpoint)) reason = KDB_REASON_KEYBOARD; - if (in_nmi()) + if (ks->err_code == KDB_REASON_SYSTEM_NMI && ks->signo == SIGTRAP) + reason = KDB_REASON_SYSTEM_NMI; + + else if (in_nmi()) reason = KDB_REASON_NMI; for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) { @@ -115,17 +118,14 @@ int kdb_stub(struct kgdb_state *ks) kdb_bp_remove(); KDB_STATE_CLEAR(DOING_SS); KDB_STATE_SET(PAGER); - /* zero out any offline cpu data */ - for_each_present_cpu(i) { - if (!cpu_online(i)) { - kgdb_info[i].debuggerinfo = NULL; - kgdb_info[i].task = NULL; - } - } if (ks->err_code == DIE_OOPS || reason == KDB_REASON_OOPS) { ks->pass_exception = 1; KDB_FLAG_SET(CATASTROPHIC); } + /* set CATASTROPHIC if the system contains unresponsive processors */ + for_each_online_cpu(i) + if (!kgdb_info[i].enter_kgdb) + KDB_FLAG_SET(CATASTROPHIC); if (KDB_STATE(SSBPT) && reason == KDB_REASON_SSTEP) { KDB_STATE_CLEAR(SSBPT); KDB_STATE_CLEAR(DOING_SS); @@ -140,14 +140,12 @@ int kdb_stub(struct kgdb_state *ks) */ kdb_common_deinit_state(); KDB_STATE_CLEAR(PAGER); - kdbnearsym_cleanup(); if (error == KDB_CMD_KGDB) { if (KDB_STATE(DOING_KGDB)) KDB_STATE_CLEAR(DOING_KGDB); return DBG_PASS_EVENT; } kdb_bp_install(ks->linux_regs); - dbg_activate_sw_breakpoints(); /* Set the exit state to a single step or a continue */ if (KDB_STATE(DOING_SS)) gdbstub_state(ks, "s"); @@ -167,7 +165,6 @@ int kdb_stub(struct kgdb_state *ks) * differently vs the gdbstub */ kgdb_single_step = 0; - dbg_deactivate_sw_breakpoints(); return DBG_SWITCH_CPU_EVENT; } return kgdb_info[ks->cpu].ret_state; diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 14ff4849262c..61c1690058ed 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -9,7 +9,6 @@ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. */ -#include <linux/module.h> #include <linux/types.h> #include <linux/ctype.h> #include <linux/kernel.h> @@ -30,6 +29,7 @@ char kdb_prompt_str[CMD_BUFLEN]; int kdb_trap_printk; +int kdb_printf_cpu = -1; static int kgdb_transition_check(char *buffer) { @@ -48,15 +48,90 @@ static int kgdb_transition_check(char *buffer) return 0; } -static int kdb_read_get_key(char *buffer, size_t bufsize) +/** + * kdb_handle_escape() - validity check on an accumulated escape sequence. + * @buf: Accumulated escape characters to be examined. Note that buf + * is not a string, it is an array of characters and need not be + * nil terminated. + * @sz: Number of accumulated escape characters. + * + * Return: -1 if the escape sequence is unwanted, 0 if it is incomplete, + * otherwise it returns a mapped key value to pass to the upper layers. + */ +static int kdb_handle_escape(char *buf, size_t sz) +{ + char *lastkey = buf + sz - 1; + + switch (sz) { + case 1: + if (*lastkey == '\e') + return 0; + break; + + case 2: /* \e<something> */ + if (*lastkey == '[') + return 0; + break; + + case 3: + switch (*lastkey) { + case 'A': /* \e[A, up arrow */ + return 16; + case 'B': /* \e[B, down arrow */ + return 14; + case 'C': /* \e[C, right arrow */ + return 6; + case 'D': /* \e[D, left arrow */ + return 2; + case '1': /* \e[<1,3,4>], may be home, del, end */ + case '3': + case '4': + return 0; + } + break; + + case 4: + if (*lastkey == '~') { + switch (buf[2]) { + case '1': /* \e[1~, home */ + return 1; + case '3': /* \e[3~, del */ + return 4; + case '4': /* \e[4~, end */ + return 5; + } + } + break; + } + + return -1; +} + +/** + * kdb_getchar() - Read a single character from a kdb console (or consoles). + * + * Other than polling the various consoles that are currently enabled, + * most of the work done in this function is dealing with escape sequences. + * + * An escape key could be the start of a vt100 control sequence such as \e[D + * (left arrow) or it could be a character in its own right. The standard + * method for detecting the difference is to wait for 2 seconds to see if there + * are any other characters. kdb is complicated by the lack of a timer service + * (interrupts are off), by multiple input sources. Escape sequence processing + * has to be done as states in the polling loop. + * + * Return: The key pressed or a control code derived from an escape sequence. + */ +char kdb_getchar(void) { #define ESCAPE_UDELAY 1000 #define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */ - char escape_data[5]; /* longest vt100 escape sequence is 4 bytes */ - char *ped = escape_data; + char buf[4]; /* longest vt100 escape sequence is 4 bytes */ + char *pbuf = buf; int escape_delay = 0; - get_char_func *f, *f_escape = NULL; + get_char_func *f, *f_prev = NULL; int key; + static bool last_char_was_cr; for (f = &kdb_poll_funcs[0]; ; ++f) { if (*f == NULL) { @@ -64,109 +139,76 @@ static int kdb_read_get_key(char *buffer, size_t bufsize) touch_nmi_watchdog(); f = &kdb_poll_funcs[0]; } - if (escape_delay == 2) { - *ped = '\0'; - ped = escape_data; - --escape_delay; - } - if (escape_delay == 1) { - key = *ped++; - if (!*ped) - --escape_delay; - break; - } + key = (*f)(); if (key == -1) { if (escape_delay) { udelay(ESCAPE_UDELAY); - --escape_delay; + if (--escape_delay == 0) + return '\e'; } continue; } - if (bufsize <= 2) { - if (key == '\r') - key = '\n'; - *buffer++ = key; - *buffer = '\0'; - return -1; + + /* + * The caller expects that newlines are either CR or LF. However + * some terminals send _both_ CR and LF. Avoid having to handle + * this in the caller by stripping the LF if we saw a CR right + * before. + */ + if (last_char_was_cr && key == '\n') { + last_char_was_cr = false; + continue; } - if (escape_delay == 0 && key == '\e') { + last_char_was_cr = (key == '\r'); + + /* + * When the first character is received (or we get a change + * input source) we set ourselves up to handle an escape + * sequences (just in case). + */ + if (f_prev != f) { + f_prev = f; + pbuf = buf; escape_delay = ESCAPE_DELAY; - ped = escape_data; - f_escape = f; - } - if (escape_delay) { - *ped++ = key; - if (f_escape != f) { - escape_delay = 2; - continue; - } - if (ped - escape_data == 1) { - /* \e */ - continue; - } else if (ped - escape_data == 2) { - /* \e<something> */ - if (key != '[') - escape_delay = 2; - continue; - } else if (ped - escape_data == 3) { - /* \e[<something> */ - int mapkey = 0; - switch (key) { - case 'A': /* \e[A, up arrow */ - mapkey = 16; - break; - case 'B': /* \e[B, down arrow */ - mapkey = 14; - break; - case 'C': /* \e[C, right arrow */ - mapkey = 6; - break; - case 'D': /* \e[D, left arrow */ - mapkey = 2; - break; - case '1': /* dropthrough */ - case '3': /* dropthrough */ - /* \e[<1,3,4>], may be home, del, end */ - case '4': - mapkey = -1; - break; - } - if (mapkey != -1) { - if (mapkey > 0) { - escape_data[0] = mapkey; - escape_data[1] = '\0'; - } - escape_delay = 2; - } - continue; - } else if (ped - escape_data == 4) { - /* \e[<1,3,4><something> */ - int mapkey = 0; - if (key == '~') { - switch (escape_data[2]) { - case '1': /* \e[1~, home */ - mapkey = 1; - break; - case '3': /* \e[3~, del */ - mapkey = 4; - break; - case '4': /* \e[4~, end */ - mapkey = 5; - break; - } - } - if (mapkey > 0) { - escape_data[0] = mapkey; - escape_data[1] = '\0'; - } - escape_delay = 2; - continue; - } } - break; /* A key to process */ + + *pbuf++ = key; + key = kdb_handle_escape(buf, pbuf - buf); + if (key < 0) /* no escape sequence; return best character */ + return buf[pbuf - buf == 2 ? 1 : 0]; + if (key > 0) + return key; } - return key; + + unreachable(); +} + +/** + * kdb_position_cursor() - Place cursor in the correct horizontal position + * @prompt: Nil-terminated string containing the prompt string + * @buffer: Nil-terminated string containing the entire command line + * @cp: Cursor position, pointer the character in buffer where the cursor + * should be positioned. + * + * The cursor is positioned by sending a carriage-return and then printing + * the content of the line until we reach the correct cursor position. + * + * There is some additional fine detail here. + * + * Firstly, even though kdb_printf() will correctly format zero-width fields + * we want the second call to kdb_printf() to be conditional. That keeps things + * a little cleaner when LOGGING=1. + * + * Secondly, we can't combine everything into one call to kdb_printf() since + * that renders into a fixed length buffer and the combined print could result + * in unwanted truncation. + */ +static void kdb_position_cursor(char *prompt, char *buffer, char *cp) +{ + kdb_printf("\r%s", prompt); + if (cp > buffer) + kdb_printf("%.*s", (int)(cp - buffer), buffer); } /* @@ -187,17 +229,7 @@ static int kdb_read_get_key(char *buffer, size_t bufsize) * function. It is not reentrant - it relies on the fact * that while kdb is running on only one "master debug" cpu. * Remarks: - * - * The buffer size must be >= 2. A buffer size of 2 means that the caller only - * wants a single key. - * - * An escape key could be the start of a vt100 control sequence such as \e[D - * (left arrow) or it could be a character in its own right. The standard - * method for detecting the difference is to wait for 2 seconds to see if there - * are any other characters. kdb is complicated by the lack of a timer service - * (interrupts are off), by multiple input sources and by the need to sometimes - * return after just one key. Escape sequence processing has to be done as - * states in the polling loop. + * The buffer size must be >= 2. */ static char *kdb_read(char *buffer, size_t bufsize) @@ -215,8 +247,7 @@ static char *kdb_read(char *buffer, size_t bufsize) int count; int i; int diag, dtab_count; - int key; - + int key, ret; diag = kdbgetintenv("DTABCOUNT", &dtab_count); if (diag) @@ -232,29 +263,21 @@ static char *kdb_read(char *buffer, size_t bufsize) *cp = '\0'; kdb_printf("%s", buffer); poll_again: - key = kdb_read_get_key(buffer, bufsize); - if (key == -1) - return buffer; + key = kdb_getchar(); if (key != 9) tab = 0; switch (key) { case 8: /* backspace */ if (cp > buffer) { - if (cp < lastchar) { - memcpy(tmpbuffer, cp, lastchar - cp); - memcpy(cp-1, tmpbuffer, lastchar - cp); - } - *(--lastchar) = '\0'; - --cp; - kdb_printf("\b%s \r", cp); - tmp = *cp; - *cp = '\0'; - kdb_printf(kdb_prompt_str); - kdb_printf("%s", buffer); - *cp = tmp; + memmove(cp-1, cp, lastchar - cp + 1); + lastchar--; + cp--; + kdb_printf("\b%s ", cp); + kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; - case 13: /* enter */ + case 10: /* linefeed */ + case 13: /* carriage return */ *lastchar++ = '\n'; *lastchar++ = '\0'; if (!KDB_STATE(KGDB_TRANS)) { @@ -265,22 +288,16 @@ poll_again: return buffer; case 4: /* Del */ if (cp < lastchar) { - memcpy(tmpbuffer, cp+1, lastchar - cp - 1); - memcpy(cp, tmpbuffer, lastchar - cp - 1); - *(--lastchar) = '\0'; - kdb_printf("%s \r", cp); - tmp = *cp; - *cp = '\0'; - kdb_printf(kdb_prompt_str); - kdb_printf("%s", buffer); - *cp = tmp; + memmove(cp, cp+1, lastchar - cp); + lastchar--; + kdb_printf("%s ", cp); + kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 1: /* Home */ if (cp > buffer) { - kdb_printf("\r"); - kdb_printf(kdb_prompt_str); cp = buffer; + kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 5: /* End */ @@ -296,11 +313,10 @@ poll_again: } break; case 14: /* Down */ - memset(tmpbuffer, ' ', - strlen(kdb_prompt_str) + (lastchar-buffer)); - *(tmpbuffer+strlen(kdb_prompt_str) + - (lastchar-buffer)) = '\0'; - kdb_printf("\r%s\r", tmpbuffer); + case 16: /* Up */ + kdb_printf("\r%*c\r", + (int)(strlen(kdb_prompt_str) + (lastchar - buffer)), + ' '); *lastchar = (char)key; *(lastchar+1) = '\0'; return lastchar; @@ -310,34 +326,19 @@ poll_again: ++cp; } break; - case 16: /* Up */ - memset(tmpbuffer, ' ', - strlen(kdb_prompt_str) + (lastchar-buffer)); - *(tmpbuffer+strlen(kdb_prompt_str) + - (lastchar-buffer)) = '\0'; - kdb_printf("\r%s\r", tmpbuffer); - *lastchar = (char)key; - *(lastchar+1) = '\0'; - return lastchar; case 9: /* Tab */ if (tab < 2) ++tab; - p_tmp = buffer; - while (*p_tmp == ' ') - p_tmp++; - if (p_tmp > cp) - break; - memcpy(tmpbuffer, p_tmp, cp-p_tmp); - *(tmpbuffer + (cp-p_tmp)) = '\0'; - p_tmp = strrchr(tmpbuffer, ' '); - if (p_tmp) - ++p_tmp; - else - p_tmp = tmpbuffer; - len = strlen(p_tmp); - count = kallsyms_symbol_complete(p_tmp, - sizeof(tmpbuffer) - - (p_tmp - tmpbuffer)); + + tmp = *cp; + *cp = '\0'; + p_tmp = strrchr(buffer, ' '); + p_tmp = (p_tmp ? p_tmp + 1 : buffer); + strscpy(tmpbuffer, p_tmp); + *cp = tmp; + + len = strlen(tmpbuffer); + count = kallsyms_symbol_complete(tmpbuffer, sizeof(tmpbuffer)); if (tab == 2 && count > 0) { kdb_printf("\n%d symbols are found.", count); if (count > dtab_count) { @@ -349,42 +350,51 @@ poll_again: } kdb_printf("\n"); for (i = 0; i < count; i++) { - if (kallsyms_symbol_next(p_tmp, i) < 0) + ret = kallsyms_symbol_next(tmpbuffer, i, sizeof(tmpbuffer)); + if (WARN_ON(!ret)) break; - kdb_printf("%s ", p_tmp); - *(p_tmp + len) = '\0'; + if (ret != -E2BIG) + kdb_printf("%s ", tmpbuffer); + else + kdb_printf("%s... ", tmpbuffer); + tmpbuffer[len] = '\0'; } if (i >= dtab_count) kdb_printf("..."); kdb_printf("\n"); - kdb_printf(kdb_prompt_str); + kdb_printf("%s", kdb_prompt_str); kdb_printf("%s", buffer); + if (cp != lastchar) + kdb_position_cursor(kdb_prompt_str, buffer, cp); } else if (tab != 2 && count > 0) { - len_tmp = strlen(p_tmp); - strncpy(p_tmp+len_tmp, cp, lastchar-cp+1); - len_tmp = strlen(p_tmp); - strncpy(cp, p_tmp+len, len_tmp-len + 1); - len = len_tmp - len; - kdb_printf("%s", cp); - cp += len; - lastchar += len; + /* How many new characters do we want from tmpbuffer? */ + len_tmp = strlen(tmpbuffer) - len; + if (lastchar + len_tmp >= bufend) + len_tmp = bufend - lastchar; + + if (len_tmp) { + /* + 1 ensures the '\0' is memmove'd */ + memmove(cp+len_tmp, cp, (lastchar-cp) + 1); + memcpy(cp, tmpbuffer+len, len_tmp); + kdb_printf("%s", cp); + cp += len_tmp; + lastchar += len_tmp; + if (cp != lastchar) + kdb_position_cursor(kdb_prompt_str, + buffer, cp); + } } kdb_nextline = 1; /* reset output line number */ break; default: if (key >= 32 && lastchar < bufend) { if (cp < lastchar) { - memcpy(tmpbuffer, cp, lastchar - cp); - memcpy(cp+1, tmpbuffer, lastchar - cp); - *++lastchar = '\0'; + memmove(cp+1, cp, lastchar - cp + 1); + lastchar++; *cp = key; - kdb_printf("%s\r", cp); + kdb_printf("%s", cp); ++cp; - tmp = *cp; - *cp = '\0'; - kdb_printf(kdb_prompt_str); - kdb_printf("%s", buffer); - *cp = tmp; + kdb_position_cursor(kdb_prompt_str, buffer, cp); } else { *++lastchar = '\0'; *cp++ = key; @@ -439,11 +449,11 @@ poll_again: * substituted for %d, %x or %o in the prompt. */ -char *kdb_getstr(char *buffer, size_t bufsize, char *prompt) +char *kdb_getstr(char *buffer, size_t bufsize, const char *prompt) { if (prompt && kdb_prompt_str != prompt) - strncpy(kdb_prompt_str, prompt, CMD_BUFLEN); - kdb_printf(kdb_prompt_str); + strscpy(kdb_prompt_str, prompt); + kdb_printf("%s", kdb_prompt_str); kdb_nextline = 1; /* Prompt and input resets line number */ return kdb_read(buffer, bufsize); } @@ -548,37 +558,102 @@ static int kdb_search_string(char *searched, char *searchfor) return 0; } -int vkdb_printf(const char *fmt, va_list ap) +static void kdb_msg_write(const char *msg, int msg_len) +{ + struct console *c; + const char *cp; + int cookie; + int len; + + if (msg_len == 0) + return; + + cp = msg; + len = msg_len; + + while (len--) { + dbg_io_ops->write_char(*cp); + cp++; + } + + /* + * The console_srcu_read_lock() only provides safe console list + * traversal. The use of the ->write() callback relies on all other + * CPUs being stopped at the moment and console drivers being able to + * handle reentrance when @oops_in_progress is set. + * + * There is no guarantee that every console driver can handle + * reentrance in this way; the developer deploying the debugger + * is responsible for ensuring that the console drivers they + * have selected handle reentrance appropriately. + */ + cookie = console_srcu_read_lock(); + for_each_console_srcu(c) { + short flags = console_srcu_read_flags(c); + + if (!console_is_usable(c, flags, true)) + continue; + if (c == dbg_io_ops->cons) + continue; + + if (flags & CON_NBCON) { + struct nbcon_write_context wctxt = { }; + + /* + * Do not continue if the console is NBCON and the context + * can't be acquired. + */ + if (!nbcon_kdb_try_acquire(c, &wctxt)) + continue; + + nbcon_write_context_set_buf(&wctxt, (char *)msg, msg_len); + + c->write_atomic(c, &wctxt); + nbcon_kdb_release(&wctxt); + } else { + /* + * Set oops_in_progress to encourage the console drivers to + * disregard their internal spin locks: in the current calling + * context the risk of deadlock is a bigger problem than risks + * due to re-entering the console driver. We operate directly on + * oops_in_progress rather than using bust_spinlocks() because + * the calls bust_spinlocks() makes on exit are not appropriate + * for this calling context. + */ + ++oops_in_progress; + c->write(c, msg, msg_len); + --oops_in_progress; + } + touch_nmi_watchdog(); + } + console_srcu_read_unlock(cookie); +} + +int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap) { int diag; int linecount; int colcount; int logging, saved_loglevel = 0; - int saved_trap_printk; - int got_printf_lock = 0; int retlen = 0; int fnd, len; + int this_cpu, old_cpu; char *cp, *cp2, *cphold = NULL, replaced_byte = ' '; char *moreprompt = "more> "; - struct console *c = console_drivers; - static DEFINE_SPINLOCK(kdb_printf_lock); - unsigned long uninitialized_var(flags); - - preempt_disable(); - saved_trap_printk = kdb_trap_printk; - kdb_trap_printk = 0; + unsigned long flags; /* Serialize kdb_printf if multiple cpus try to write at once. * But if any cpu goes recursive in kdb, just print the output, * even if it is interleaved with any other text. */ - if (!KDB_STATE(PRINTF_LOCK)) { - KDB_STATE_SET(PRINTF_LOCK); - spin_lock_irqsave(&kdb_printf_lock, flags); - got_printf_lock = 1; - atomic_inc(&kdb_event); - } else { - __acquire(kdb_printf_lock); + local_irq_save(flags); + this_cpu = smp_processor_id(); + for (;;) { + old_cpu = cmpxchg(&kdb_printf_cpu, -1, this_cpu); + if (old_cpu == -1 || old_cpu == this_cpu) + break; + + cpu_relax(); } diag = kdbgetintenv("LINES", &linecount); @@ -656,8 +731,8 @@ int vkdb_printf(const char *fmt, va_list ap) * it, depending on the results of the search. */ cp++; /* to byte after the newline */ - replaced_byte = *cp; /* remember what/where it was */ - cphold = cp; + replaced_byte = *cp; /* remember what it was */ + cphold = cp; /* remember where it was */ *cp = '\0'; /* end the string for our search */ /* @@ -674,12 +749,23 @@ int vkdb_printf(const char *fmt, va_list ap) * Shift the buffer left. */ *cphold = replaced_byte; - strcpy(kdb_buffer, cphold); - len = strlen(kdb_buffer); + len = strlen(cphold); + /* Use memmove() because the buffers overlap */ + memmove(kdb_buffer, cphold, len + 1); next_avail = kdb_buffer + len; size_avail = sizeof(kdb_buffer) - len; goto kdb_print_out; } + if (kdb_grepping_flag >= KDB_GREPPING_FLAG_SEARCH) { + /* + * This was a interactive search (using '/' at more + * prompt) and it has completed. Replace the \0 with + * its original value to ensure multi-line strings + * are handled properly, and return to normal mode. + */ + *cphold = replaced_byte; + kdb_grepping_flag = 0; + } /* * at this point the string is a full line and * should be printed, up to the null. @@ -691,27 +777,19 @@ kdb_printit: * Write to all consoles. */ retlen = strlen(kdb_buffer); - if (!dbg_kdb_mode && kgdb_connected) { - gdbstub_msg_write(kdb_buffer, retlen); - } else { - if (dbg_io_ops && !dbg_io_ops->is_console) { - len = retlen; - cp = kdb_buffer; - while (len--) { - dbg_io_ops->write_char(*cp); - cp++; - } - } - while (c) { - c->write(c, kdb_buffer, retlen); - touch_nmi_watchdog(); - c = c->next; - } - } + cp = (char *) printk_skip_headers(kdb_buffer); + if (!dbg_kdb_mode && kgdb_connected) + gdbstub_msg_write(cp, retlen - (cp - kdb_buffer)); + else + kdb_msg_write(cp, retlen - (cp - kdb_buffer)); + if (logging) { saved_loglevel = console_loglevel; - console_loglevel = 0; - printk(KERN_INFO "%s", kdb_buffer); + console_loglevel = CONSOLE_LOGLEVEL_SILENT; + if (printk_get_level(kdb_buffer) || src == KDB_MSGSRC_PRINTK) + printk("%s", kdb_buffer); + else + pr_info("%s", kdb_buffer); } if (KDB_STATE(PAGER)) { @@ -737,7 +815,7 @@ kdb_printit: /* check for having reached the LINES number of printed lines */ if (kdb_nextline >= linecount) { - char buf1[16] = ""; + char ch; /* Watch out for recursion here. Any routine that calls * kdb_printf will come back through here. And kdb_read @@ -753,52 +831,49 @@ kdb_printit: moreprompt = "more> "; kdb_input_flush(); - c = console_drivers; - - if (dbg_io_ops && !dbg_io_ops->is_console) { - len = strlen(moreprompt); - cp = moreprompt; - while (len--) { - dbg_io_ops->write_char(*cp); - cp++; - } - } - while (c) { - c->write(c, moreprompt, strlen(moreprompt)); - touch_nmi_watchdog(); - c = c->next; - } + kdb_msg_write(moreprompt, strlen(moreprompt)); if (logging) printk("%s", moreprompt); - kdb_read(buf1, 2); /* '2' indicates to return - * immediately after getting one key. */ + ch = kdb_getchar(); kdb_nextline = 1; /* Really set output line 1 */ /* empty and reset the buffer: */ kdb_buffer[0] = '\0'; next_avail = kdb_buffer; size_avail = sizeof(kdb_buffer); - if ((buf1[0] == 'q') || (buf1[0] == 'Q')) { + if ((ch == 'q') || (ch == 'Q')) { /* user hit q or Q */ KDB_FLAG_SET(CMD_INTERRUPT); /* command interrupted */ KDB_STATE_CLEAR(PAGER); /* end of command output; back to normal mode */ kdb_grepping_flag = 0; kdb_printf("\n"); - } else if (buf1[0] == ' ') { + } else if (ch == ' ') { kdb_printf("\r"); suspend_grep = 1; /* for this recursion */ - } else if (buf1[0] == '\n') { + } else if (ch == '\n' || ch == '\r') { kdb_nextline = linecount - 1; kdb_printf("\r"); suspend_grep = 1; /* for this recursion */ - } else if (buf1[0] && buf1[0] != '\n') { - /* user hit something other than enter */ + } else if (ch == '/' && !kdb_grepping_flag) { + kdb_printf("\r"); + kdb_getstr(kdb_grep_string, KDB_GREP_STRLEN, + kdbgetenv("SEARCHPROMPT") ?: "search> "); + *strchrnul(kdb_grep_string, '\n') = '\0'; + kdb_grepping_flag += KDB_GREPPING_FLAG_SEARCH; + suspend_grep = 1; /* for this recursion */ + } else if (ch) { + /* user hit something unexpected */ suspend_grep = 1; /* for this recursion */ - kdb_printf("\nOnly 'q' or 'Q' are processed at more " - "prompt, input ignored\n"); + if (ch != '/') + kdb_printf( + "\nOnly 'q', 'Q' or '/' are processed at " + "more prompt, input ignored\n"); + else + kdb_printf("\n'/' cannot be used during | " + "grep filtering, input ignored\n"); } else if (kdb_grepping_flag) { /* user hit enter */ suspend_grep = 1; /* for this recursion */ @@ -815,8 +890,9 @@ kdb_printit: */ if (kdb_grepping_flag && !suspend_grep) { *cphold = replaced_byte; - strcpy(kdb_buffer, cphold); - len = strlen(kdb_buffer); + len = strlen(cphold); + /* Use memmove() because the buffers overlap */ + memmove(kdb_buffer, cphold, len + 1); next_avail = kdb_buffer + len; size_avail = sizeof(kdb_buffer) - len; } @@ -825,16 +901,9 @@ kdb_print_out: suspend_grep = 0; /* end of what may have been a recursive call */ if (logging) console_loglevel = saved_loglevel; - if (KDB_STATE(PRINTF_LOCK) && got_printf_lock) { - got_printf_lock = 0; - spin_unlock_irqrestore(&kdb_printf_lock, flags); - KDB_STATE_CLEAR(PRINTF_LOCK); - atomic_dec(&kdb_event); - } else { - __release(kdb_printf_lock); - } - kdb_trap_printk = saved_trap_printk; - preempt_enable(); + /* kdb_printf_cpu locked the code above. */ + smp_store_release(&kdb_printf_cpu, old_cpu); + local_irq_restore(flags); return retlen; } @@ -844,7 +913,7 @@ int kdb_printf(const char *fmt, ...) int r; va_start(ap, fmt); - r = vkdb_printf(fmt, ap); + r = vkdb_printf(KDB_MSGSRC_INTERNAL, fmt, ap); va_end(ap); return r; diff --git a/kernel/debug/kdb/kdb_keyboard.c b/kernel/debug/kdb/kdb_keyboard.c index 118527aa60ea..386d30e530b7 100644 --- a/kernel/debug/kdb/kdb_keyboard.c +++ b/kernel/debug/kdb/kdb_keyboard.c @@ -11,9 +11,10 @@ #include <linux/kdb.h> #include <linux/keyboard.h> #include <linux/ctype.h> -#include <linux/module.h> #include <linux/io.h> +#include "kdb_private.h" + /* Keyboard Controller Registers on normal PCs. */ #define KBD_STATUS_REG 0x64 /* Status register (R) */ @@ -24,6 +25,8 @@ #define KBD_STAT_OBF 0x01 /* Keyboard output buffer full */ #define KBD_STAT_MOUSE_OBF 0x20 /* Mouse output buffer full */ +#define CTRL(c) ((c) - 64) + static int kbd_exists; static int kbd_last_ret; @@ -122,29 +125,26 @@ int kdb_get_kbd_char(void) return 8; } - /* Special Key */ + /* Translate special keys to equivalent CTRL control characters */ switch (scancode) { case 0xF: /* Tab */ - return 9; + return CTRL('I'); case 0x53: /* Del */ - return 4; + return CTRL('D'); case 0x47: /* Home */ - return 1; + return CTRL('A'); case 0x4F: /* End */ - return 5; + return CTRL('E'); case 0x4B: /* Left */ - return 2; + return CTRL('B'); case 0x48: /* Up */ - return 16; + return CTRL('P'); case 0x50: /* Down */ - return 14; + return CTRL('N'); case 0x4D: /* Right */ - return 6; + return CTRL('F'); } - if (scancode == 0xe0) - return -1; - /* * For Japanese 86/106 keyboards * See comment in drivers/char/pc_keyb.c. @@ -171,13 +171,26 @@ int kdb_get_kbd_char(void) switch (KTYP(keychar)) { case KT_LETTER: case KT_LATIN: + switch (keychar) { + /* non-printable supported control characters */ + case CTRL('A'): /* Home */ + case CTRL('B'): /* Left */ + case CTRL('D'): /* Del */ + case CTRL('E'): /* End */ + case CTRL('F'): /* Right */ + case CTRL('I'): /* Tab */ + case CTRL('N'): /* Down */ + case CTRL('P'): /* Up */ + return keychar; + } + if (isprint(keychar)) break; /* printable characters */ - /* drop through */ + fallthrough; case KT_SPEC: if (keychar == K_ENTER) break; - /* drop through */ + fallthrough; default: return -1; /* ignore unprintables */ } diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 00eb8f7fbf41..dddf2b5aad57 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -12,17 +12,20 @@ */ #include <linux/ctype.h> +#include <linux/types.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/kmsg_dump.h> #include <linux/reboot.h> #include <linux/sched.h> +#include <linux/sched/loadavg.h> +#include <linux/sched/stat.h> +#include <linux/sched/debug.h> #include <linux/sysrq.h> #include <linux/smp.h> #include <linux/utsname.h> #include <linux/vmalloc.h> -#include <linux/atomic.h> -#include <linux/module.h> +#include <linux/moduleparam.h> #include <linux/mm.h> #include <linux/init.h> #include <linux/kallsyms.h> @@ -40,10 +43,16 @@ #include <linux/proc_fs.h> #include <linux/uaccess.h> #include <linux/slab.h> +#include <linux/security.h> #include "kdb_private.h" -#define GREP_LEN 256 -char kdb_grep_string[GREP_LEN]; +#undef MODULE_PARAM_PREFIX +#define MODULE_PARAM_PREFIX "kdb." + +static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE; +module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600); + +char kdb_grep_string[KDB_GREP_STRLEN]; int kdb_grepping_flag; EXPORT_SYMBOL(kdb_grepping_flag); int kdb_grep_leading; @@ -52,8 +61,7 @@ int kdb_grep_trailing; /* * Kernel debugger state flags */ -int kdb_flags; -atomic_t kdb_event; +unsigned int kdb_flags; /* * kdb_lock protects updates to kdb_initial_cpu. Used to @@ -64,7 +72,6 @@ int kdb_nextline = 1; int kdb_state; /* General KDB state */ struct task_struct *kdb_current_task; -EXPORT_SYMBOL(kdb_current_task); struct pt_regs *kdb_current_regs; const char *kdb_diemsg; @@ -76,15 +83,8 @@ static unsigned int kdb_continue_catastrophic = static unsigned int kdb_continue_catastrophic; #endif -/* kdb_commands describes the available commands. */ -static kdbtab_t *kdb_commands; -#define KDB_BASE_CMD_MAX 50 -static int kdb_max_commands = KDB_BASE_CMD_MAX; -static kdbtab_t kdb_base_commands[KDB_BASE_CMD_MAX]; -#define for_each_kdbcmd(cmd, num) \ - for ((cmd) = kdb_base_commands, (num) = 0; \ - num < kdb_max_commands; \ - num++, num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++) +/* kdb_cmds_head describes the available commands. */ +static LIST_HEAD(kdb_cmds_head); typedef struct _kdbmsg { int km_diag; /* kdb diagnostic */ @@ -104,7 +104,7 @@ static kdbmsg_t kdbmsgs[] = { KDBMSG(NOENVVALUE, "Environment variable should have value"), KDBMSG(NOTIMP, "Command not implemented"), KDBMSG(ENVFULL, "Environment full"), - KDBMSG(ENVBUFFULL, "Environment buffer full"), + KDBMSG(KMALLOCFAILED, "Failed to allocate memory"), KDBMSG(TOOMANYBPT, "Too many breakpoints defined"), #ifdef CONFIG_CPU_XSCALE KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"), @@ -121,6 +121,7 @@ static kdbmsg_t kdbmsgs[] = { KDBMSG(BADLENGTH, "Invalid length field"), KDBMSG(NOBP, "No Breakpoint exists"), KDBMSG(BADADDR, "Invalid address"), + KDBMSG(NOPERM, "Permission denied"), }; #undef KDBMSG @@ -128,63 +129,97 @@ static const int __nkdb_err = ARRAY_SIZE(kdbmsgs); /* - * Initial environment. This is all kept static and local to - * this file. We don't want to rely on the memory allocation - * mechanisms in the kernel, so we use a very limited allocate-only - * heap for new and altered environment variables. The entire - * environment is limited to a fixed number of entries (add more - * to __env[] if required) and a fixed amount of heap (add more to - * KDB_ENVBUFSIZE if required). + * Initial environment. This is all kept static and local to this file. + * The entire environment is limited to a fixed number of entries + * (add more to __env[] if required) */ -static char *__env[] = { +static char *__env[31] = { #if defined(CONFIG_SMP) - "PROMPT=[%d]kdb> ", + "PROMPT=[%d]kdb> ", #else - "PROMPT=kdb> ", + "PROMPT=kdb> ", #endif - "MOREPROMPT=more> ", - "RADIX=16", - "MDCOUNT=8", /* lines of md output */ - KDB_PLATFORM_ENV, - "DTABCOUNT=30", - "NOSECT=1", - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, - (char *)0, + "MOREPROMPT=more> ", + "RADIX=16", + "MDCOUNT=8", /* lines of md output */ + KDB_PLATFORM_ENV, + "DTABCOUNT=30", + "NOSECT=1", }; static const int __nenv = ARRAY_SIZE(__env); -struct task_struct *kdb_curr_task(int cpu) +/* + * Update the permissions flags (kdb_cmd_enabled) to match the + * current lockdown state. + * + * Within this function the calls to security_locked_down() are "lazy". We + * avoid calling them if the current value of kdb_cmd_enabled already excludes + * flags that might be subject to lockdown. Additionally we deliberately check + * the lockdown flags independently (even though read lockdown implies write + * lockdown) since that results in both simpler code and clearer messages to + * the user on first-time debugger entry. + * + * The permission masks during a read+write lockdown permits the following + * flags: INSPECT, SIGNAL, REBOOT (and ALWAYS_SAFE). + * + * The INSPECT commands are not blocked during lockdown because they are + * not arbitrary memory reads. INSPECT covers the backtrace family (sometimes + * forcing them to have no arguments) and lsmod. These commands do expose + * some kernel state but do not allow the developer seated at the console to + * choose what state is reported. SIGNAL and REBOOT should not be controversial, + * given these are allowed for root during lockdown already. + */ +static void kdb_check_for_lockdown(void) { - struct task_struct *p = curr_task(cpu); -#ifdef _TIF_MCA_INIT - if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu)) - p = krp->p; -#endif - return p; + const int write_flags = KDB_ENABLE_MEM_WRITE | + KDB_ENABLE_REG_WRITE | + KDB_ENABLE_FLOW_CTRL; + const int read_flags = KDB_ENABLE_MEM_READ | + KDB_ENABLE_REG_READ; + + bool need_to_lockdown_write = false; + bool need_to_lockdown_read = false; + + if (kdb_cmd_enabled & (KDB_ENABLE_ALL | write_flags)) + need_to_lockdown_write = + security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL); + + if (kdb_cmd_enabled & (KDB_ENABLE_ALL | read_flags)) + need_to_lockdown_read = + security_locked_down(LOCKDOWN_DBG_READ_KERNEL); + + /* De-compose KDB_ENABLE_ALL if required */ + if (need_to_lockdown_write || need_to_lockdown_read) + if (kdb_cmd_enabled & KDB_ENABLE_ALL) + kdb_cmd_enabled = KDB_ENABLE_MASK & ~KDB_ENABLE_ALL; + + if (need_to_lockdown_write) + kdb_cmd_enabled &= ~write_flags; + + if (need_to_lockdown_read) + kdb_cmd_enabled &= ~read_flags; +} + +/* + * Check whether the flags of the current command, the permissions of the kdb + * console and the lockdown state allow a command to be run. + */ +static bool kdb_check_flags(kdb_cmdflags_t flags, int permissions, + bool no_args) +{ + /* permissions comes from userspace so needs massaging slightly */ + permissions &= KDB_ENABLE_MASK; + permissions |= KDB_ENABLE_ALWAYS_SAFE; + + /* some commands change group when launched with no arguments */ + if (no_args) + permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT; + + flags |= KDB_ENABLE_ALL; + + return permissions & flags; } /* @@ -219,42 +254,12 @@ char *kdbgetenv(const char *match) } /* - * kdballocenv - This function is used to allocate bytes for - * environment entries. - * Parameters: - * match A character string representing a numeric value - * Outputs: - * *value the unsigned long representation of the env variable 'match' - * Returns: - * Zero on success, a kdb diagnostic on failure. - * Remarks: - * We use a static environment buffer (envbuffer) to hold the values - * of dynamically generated environment variables (see kdb_set). Buffer - * space once allocated is never free'd, so over time, the amount of space - * (currently 512 bytes) will be exhausted if env variables are changed - * frequently. - */ -static char *kdballocenv(size_t bytes) -{ -#define KDB_ENVBUFSIZE 512 - static char envbuffer[KDB_ENVBUFSIZE]; - static int envbufsize; - char *ep = NULL; - - if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) { - ep = &envbuffer[envbufsize]; - envbufsize += bytes; - } - return ep; -} - -/* * kdbgetulenv - This function will return the value of an unsigned * long-valued environment variable. * Parameters: * match A character string representing a numeric value * Outputs: - * *value the unsigned long represntation of the env variable 'match' + * *value the unsigned long representation of the env variable 'match' * Returns: * Zero on success, a kdb diagnostic on failure. */ @@ -267,8 +272,8 @@ static int kdbgetulenv(const char *match, unsigned long *value) return KDB_NOTENV; if (strlen(ep) == 0) return KDB_NOENVVALUE; - - *value = simple_strtoul(ep, NULL, 0); + if (kstrtoul(ep, 0, value)) + return KDB_BADINT; return 0; } @@ -295,53 +300,84 @@ int kdbgetintenv(const char *match, int *value) } /* + * kdb_setenv() - Alter an existing environment variable or create a new one. + * @var: Name of the variable + * @val: Value of the variable + * + * Return: Zero on success, a kdb diagnostic on failure. + */ +static int kdb_setenv(const char *var, const char *val) +{ + int i; + char *ep; + size_t varlen, vallen; + + varlen = strlen(var); + vallen = strlen(val); + ep = kmalloc(varlen + vallen + 2, GFP_KDB); + if (!ep) + return KDB_KMALLOCFAILED; + + sprintf(ep, "%s=%s", var, val); + + for (i = 0; i < __nenv; i++) { + if (__env[i] + && ((strncmp(__env[i], var, varlen) == 0) + && ((__env[i][varlen] == '\0') + || (__env[i][varlen] == '=')))) { + kfree_const(__env[i]); + __env[i] = ep; + return 0; + } + } + + /* + * Wasn't existing variable. Fit into slot. + */ + for (i = 0; i < __nenv-1; i++) { + if (__env[i] == (char *)0) { + __env[i] = ep; + return 0; + } + } + + return KDB_ENVFULL; +} + +/* + * kdb_printenv() - Display the current environment variables. + */ +static void kdb_printenv(void) +{ + int i; + + for (i = 0; i < __nenv; i++) { + if (__env[i]) + kdb_printf("%s\n", __env[i]); + } +} + +/* * kdbgetularg - This function will convert a numeric string into an * unsigned long value. * Parameters: * arg A character string representing a numeric value * Outputs: - * *value the unsigned long represntation of arg. + * *value the unsigned long representation of arg. * Returns: * Zero on success, a kdb diagnostic on failure. */ int kdbgetularg(const char *arg, unsigned long *value) { - char *endp; - unsigned long val; - - val = simple_strtoul(arg, &endp, 0); - - if (endp == arg) { - /* - * Also try base 16, for us folks too lazy to type the - * leading 0x... - */ - val = simple_strtoul(arg, &endp, 16); - if (endp == arg) - return KDB_BADINT; - } - - *value = val; - + if (kstrtoul(arg, 0, value)) + return KDB_BADINT; return 0; } int kdbgetu64arg(const char *arg, u64 *value) { - char *endp; - u64 val; - - val = simple_strtoull(arg, &endp, 0); - - if (endp == arg) { - - val = simple_strtoull(arg, &endp, 16); - if (endp == arg) - return KDB_BADINT; - } - - *value = val; - + if (kstrtou64(arg, 0, value)) + return KDB_BADINT; return 0; } @@ -351,10 +387,6 @@ int kdbgetu64arg(const char *arg, u64 *value) */ int kdb_set(int argc, const char **argv) { - int i; - char *ep; - size_t varlen, vallen; - /* * we can be invoked two ways: * set var=value argv[1]="var", argv[2]="value" @@ -370,20 +402,26 @@ int kdb_set(int argc, const char **argv) return KDB_ARGCOUNT; /* + * Censor sensitive variables + */ + if (strcmp(argv[1], "PROMPT") == 0 && + !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false)) + return KDB_NOPERM; + + /* * Check for internal variables */ if (strcmp(argv[1], "KDBDEBUG") == 0) { unsigned int debugflags; - char *cp; + int ret; - debugflags = simple_strtoul(argv[2], &cp, 0); - if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) { + ret = kstrtouint(argv[2], 0, &debugflags); + if (ret || debugflags & ~KDB_DEBUG_FLAG_MASK) { kdb_printf("kdb: illegal debug flags '%s'\n", argv[2]); return 0; } - kdb_flags = (kdb_flags & - ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT)) + kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK)) | (debugflags << KDB_DEBUG_FLAG_SHIFT); return 0; @@ -393,37 +431,7 @@ int kdb_set(int argc, const char **argv) * Tokenizer squashed the '=' sign. argv[1] is variable * name, argv[2] = value. */ - varlen = strlen(argv[1]); - vallen = strlen(argv[2]); - ep = kdballocenv(varlen + vallen + 2); - if (ep == (char *)0) - return KDB_ENVBUFFULL; - - sprintf(ep, "%s=%s", argv[1], argv[2]); - - ep[varlen+vallen+1] = '\0'; - - for (i = 0; i < __nenv; i++) { - if (__env[i] - && ((strncmp(__env[i], argv[1], varlen) == 0) - && ((__env[i][varlen] == '\0') - || (__env[i][varlen] == '=')))) { - __env[i] = ep; - return 0; - } - } - - /* - * Wasn't existing variable. Fit into slot. - */ - for (i = 0; i < __nenv-1; i++) { - if (__env[i] == (char *)0) { - __env[i] = ep; - return 0; - } - } - - return KDB_ENVFULL; + return kdb_setenv(argv[1], argv[2]); } static int kdb_check_regs(void) @@ -442,7 +450,7 @@ static int kdb_check_regs(void) * symbol name, and offset to the caller. * * The argument may consist of a numeric value (decimal or - * hexidecimal), a symbol name, a register name (preceded by the + * hexadecimal), a symbol name, a register name (preceded by the * percent sign), an environment variable with a numeric value * (preceded by a dollar sign) or a simple arithmetic expression * consisting of a symbol name, +/-, and a numeric constant value @@ -476,6 +484,15 @@ int kdbgetaddrarg(int argc, const char **argv, int *nextarg, kdb_symtab_t symtab; /* + * If the enable flags prohibit both arbitrary memory access + * and flow control then there are no reasonable grounds to + * provide symbol lookup. + */ + if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL, + kdb_cmd_enabled, false)) + return KDB_NOPERM; + + /* * Process arguments which follow the following syntax: * * symbol | numeric-address [+/- numeric-offset] @@ -617,65 +634,73 @@ static void kdb_cmderror(int diag) * Returns: * zero for success, a kdb diagnostic if error */ -struct defcmd_set { - int count; - int usable; - char *name; - char *usage; - char *help; - char **command; +struct kdb_macro { + kdbtab_t cmd; /* Macro command */ + struct list_head statements; /* Associated statement list */ +}; + +struct kdb_macro_statement { + char *statement; /* Statement text */ + struct list_head list_node; /* Statement list node */ }; -static struct defcmd_set *defcmd_set; -static int defcmd_set_count; -static int defcmd_in_progress; + +static struct kdb_macro *kdb_macro; +static bool defcmd_in_progress; /* Forward references */ static int kdb_exec_defcmd(int argc, const char **argv); static int kdb_defcmd2(const char *cmdstr, const char *argv0) { - struct defcmd_set *s = defcmd_set + defcmd_set_count - 1; - char **save_command = s->command; + struct kdb_macro_statement *kms; + + if (!kdb_macro) + return KDB_NOTIMP; + if (strcmp(argv0, "endefcmd") == 0) { - defcmd_in_progress = 0; - if (!s->count) - s->usable = 0; - if (s->usable) - kdb_register(s->name, kdb_exec_defcmd, - s->usage, s->help, 0); + defcmd_in_progress = false; + if (!list_empty(&kdb_macro->statements)) + kdb_register(&kdb_macro->cmd); return 0; } - if (!s->usable) - return KDB_NOTIMP; - s->command = kzalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB); - if (!s->command) { - kdb_printf("Could not allocate new kdb_defcmd table for %s\n", + + kms = kmalloc(sizeof(*kms), GFP_KDB); + if (!kms) { + kdb_printf("Could not allocate new kdb macro command: %s\n", cmdstr); - s->usable = 0; return KDB_NOTIMP; } - memcpy(s->command, save_command, s->count * sizeof(*(s->command))); - s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB); - kfree(save_command); + + kms->statement = kdb_strdup(cmdstr, GFP_KDB); + list_add_tail(&kms->list_node, &kdb_macro->statements); + return 0; } static int kdb_defcmd(int argc, const char **argv) { - struct defcmd_set *save_defcmd_set = defcmd_set, *s; + kdbtab_t *mp; + if (defcmd_in_progress) { kdb_printf("kdb: nested defcmd detected, assuming missing " "endefcmd\n"); kdb_defcmd2("endefcmd", "endefcmd"); } if (argc == 0) { - int i; - for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) { - kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name, - s->usage, s->help); - for (i = 0; i < s->count; ++i) - kdb_printf("%s", s->command[i]); - kdb_printf("endefcmd\n"); + kdbtab_t *kp; + struct kdb_macro *kmp; + struct kdb_macro_statement *kms; + + list_for_each_entry(kp, &kdb_cmds_head, list_node) { + if (kp->func == kdb_exec_defcmd) { + kdb_printf("defcmd %s \"%s\" \"%s\"\n", + kp->name, kp->usage, kp->help); + kmp = container_of(kp, struct kdb_macro, cmd); + list_for_each_entry(kms, &kmp->statements, + list_node) + kdb_printf("%s", kms->statement); + kdb_printf("endefcmd\n"); + } } return 0; } @@ -685,45 +710,35 @@ static int kdb_defcmd(int argc, const char **argv) kdb_printf("Command only available during kdb_init()\n"); return KDB_NOTIMP; } - defcmd_set = kmalloc((defcmd_set_count + 1) * sizeof(*defcmd_set), - GFP_KDB); - if (!defcmd_set) + kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB); + if (!kdb_macro) goto fail_defcmd; - memcpy(defcmd_set, save_defcmd_set, - defcmd_set_count * sizeof(*defcmd_set)); - s = defcmd_set + defcmd_set_count; - memset(s, 0, sizeof(*s)); - s->usable = 1; - s->name = kdb_strdup(argv[1], GFP_KDB); - if (!s->name) + + mp = &kdb_macro->cmd; + mp->func = kdb_exec_defcmd; + mp->minlen = 0; + mp->flags = KDB_ENABLE_ALWAYS_SAFE; + mp->name = kdb_strdup(argv[1], GFP_KDB); + if (!mp->name) goto fail_name; - s->usage = kdb_strdup(argv[2], GFP_KDB); - if (!s->usage) + mp->usage = kdb_strdup_dequote(argv[2], GFP_KDB); + if (!mp->usage) goto fail_usage; - s->help = kdb_strdup(argv[3], GFP_KDB); - if (!s->help) + mp->help = kdb_strdup_dequote(argv[3], GFP_KDB); + if (!mp->help) goto fail_help; - if (s->usage[0] == '"') { - strcpy(s->usage, argv[2]+1); - s->usage[strlen(s->usage)-1] = '\0'; - } - if (s->help[0] == '"') { - strcpy(s->help, argv[3]+1); - s->help[strlen(s->help)-1] = '\0'; - } - ++defcmd_set_count; - defcmd_in_progress = 1; - kfree(save_defcmd_set); + + INIT_LIST_HEAD(&kdb_macro->statements); + defcmd_in_progress = true; return 0; fail_help: - kfree(s->usage); + kfree(mp->usage); fail_usage: - kfree(s->name); + kfree(mp->name); fail_name: - kfree(defcmd_set); + kfree(kdb_macro); fail_defcmd: - kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]); - defcmd_set = save_defcmd_set; + kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]); return KDB_NOTIMP; } @@ -738,25 +753,31 @@ fail_defcmd: */ static int kdb_exec_defcmd(int argc, const char **argv) { - int i, ret; - struct defcmd_set *s; + int ret; + kdbtab_t *kp; + struct kdb_macro *kmp; + struct kdb_macro_statement *kms; + if (argc != 0) return KDB_ARGCOUNT; - for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) { - if (strcmp(s->name, argv[0]) == 0) + + list_for_each_entry(kp, &kdb_cmds_head, list_node) { + if (strcmp(kp->name, argv[0]) == 0) break; } - if (i == defcmd_set_count) { + if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) { kdb_printf("kdb_exec_defcmd: could not find commands for %s\n", argv[0]); return KDB_NOTIMP; } - for (i = 0; i < s->count; ++i) { - /* Recursive use of kdb_parse, do not use argv after - * this point */ + kmp = container_of(kp, struct kdb_macro, cmd); + list_for_each_entry(kms, &kmp->statements, list_node) { + /* + * Recursive use of kdb_parse, do not use argv after this point. + */ argv = NULL; - kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]); - ret = kdb_parse(s->command[i]); + kdb_printf("[%s]kdb> %s\n", kmp->cmd.name, kms->statement); + ret = kdb_parse(kms->statement); if (ret) return ret; } @@ -786,7 +807,7 @@ static void parse_grep(const char *str) cp++; while (isspace(*cp)) cp++; - if (strncmp(cp, "grep ", 5)) { + if (!str_has_prefix(cp, "grep ")) { kdb_printf("invalid 'pipe', see grephelp\n"); return; } @@ -827,11 +848,11 @@ static void parse_grep(const char *str) len = strlen(cp); if (!len) return; - if (len >= GREP_LEN) { + if (len >= KDB_GREP_STRLEN) { kdb_printf("search string too long\n"); return; } - strcpy(kdb_grep_string, cp); + memcpy(kdb_grep_string, cp, len + 1); kdb_grepping_flag++; return; } @@ -852,7 +873,7 @@ static void parse_grep(const char *str) * Limited to 20 tokens. * * Real rudimentary tokenization. Basically only whitespace - * is considered a token delimeter (but special consideration + * is considered a token delimiter (but special consideration * is taken of the '=' sign as used by the 'set' command). * * The algorithm used to tokenize the input string relies on @@ -872,13 +893,12 @@ int kdb_parse(const char *cmdstr) char *cp; char *cpp, quoted; kdbtab_t *tp; - int i, escaped, ignore_errors = 0, check_grep; + int escaped, ignore_errors = 0, check_grep = 0; /* * First tokenize the command string. */ cp = (char *)cmdstr; - kdb_grepping_flag = check_grep = 0; if (KDB_FLAG(CMD_INTERRUPT)) { /* Previous command was interrupted, newline must not @@ -963,25 +983,17 @@ int kdb_parse(const char *cmdstr) ++argv[0]; } - for_each_kdbcmd(tp, i) { - if (tp->cmd_name) { - /* - * If this command is allowed to be abbreviated, - * check to see if this is it. - */ - - if (tp->cmd_minlen - && (strlen(argv[0]) <= tp->cmd_minlen)) { - if (strncmp(argv[0], - tp->cmd_name, - tp->cmd_minlen) == 0) { - break; - } - } + list_for_each_entry(tp, &kdb_cmds_head, list_node) { + /* + * If this command is allowed to be abbreviated, + * check to see if this is it. + */ + if (tp->minlen && (strlen(argv[0]) <= tp->minlen) && + (strncmp(argv[0], tp->name, tp->minlen) == 0)) + break; - if (strcmp(argv[0], tp->cmd_name) == 0) - break; - } + if (strcmp(argv[0], tp->name) == 0) + break; } /* @@ -989,39 +1001,31 @@ int kdb_parse(const char *cmdstr) * few characters of this match any of the known commands. * e.g., md1c20 should match md. */ - if (i == kdb_max_commands) { - for_each_kdbcmd(tp, i) { - if (tp->cmd_name) { - if (strncmp(argv[0], - tp->cmd_name, - strlen(tp->cmd_name)) == 0) { - break; - } - } + if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) { + list_for_each_entry(tp, &kdb_cmds_head, list_node) { + if (strncmp(argv[0], tp->name, strlen(tp->name)) == 0) + break; } } - if (i < kdb_max_commands) { + if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) { int result; + + if (!kdb_check_flags(tp->flags, kdb_cmd_enabled, argc <= 1)) + return KDB_NOPERM; + KDB_STATE_SET(CMD); - result = (*tp->cmd_func)(argc-1, (const char **)argv); + result = (*tp->func)(argc-1, (const char **)argv); if (result && ignore_errors && result > KDB_CMD_GO) result = 0; KDB_STATE_CLEAR(CMD); - switch (tp->cmd_repeat) { - case KDB_REPEAT_NONE: - argc = 0; - if (argv[0]) - *(argv[0]) = '\0'; - break; - case KDB_REPEAT_NO_ARGS: - argc = 1; - if (argv[1]) - *(argv[1]) = '\0'; - break; - case KDB_REPEAT_WITH_ARGS: - break; - } + + if (tp->flags & KDB_REPEAT_WITH_ARGS) + return result; + + argc = tp->flags & KDB_REPEAT_NO_ARGS ? 1 : 0; + if (argv[argc]) + *(argv[argc]) = '\0'; return result; } @@ -1062,13 +1066,14 @@ static int handle_ctrl_cmd(char *cmd) switch (*cmd) { case CTRL_P: if (cmdptr != cmd_tail) - cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT; - strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN); + cmdptr = (cmdptr + KDB_CMD_HISTORY_COUNT - 1) % + KDB_CMD_HISTORY_COUNT; + strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN); return 1; case CTRL_N: if (cmdptr != cmd_head) cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT; - strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN); + strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN); return 1; } return 0; @@ -1091,7 +1096,7 @@ static int kdb_reboot(int argc, const char **argv) static void kdb_dumpregs(struct pt_regs *regs) { int old_lvl = console_loglevel; - console_loglevel = 15; + console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH; kdb_trap_printk++; show_regs(regs); kdb_trap_printk--; @@ -1099,7 +1104,7 @@ static void kdb_dumpregs(struct pt_regs *regs) console_loglevel = old_lvl; } -void kdb_set_current_task(struct task_struct *p) +static void kdb_set_current_task(struct task_struct *p) { kdb_current_task = p; @@ -1110,6 +1115,16 @@ void kdb_set_current_task(struct task_struct *p) kdb_current_regs = NULL; } +static void drop_newline(char *buf) +{ + size_t len = strlen(buf); + + if (len == 0) + return; + if (*(buf + len - 1) == '\n') + *(buf + len - 1) = '\0'; +} + /* * kdb_local - The main code for kdb. This routine is invoked on a * specific processor, it is not global. The main kdb() routine @@ -1135,14 +1150,17 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, char *cmdbuf; int diag; struct task_struct *kdb_current = - kdb_curr_task(raw_smp_processor_id()); + curr_task(raw_smp_processor_id()); KDB_DEBUG_STATE("kdb_local 1", reason); + + kdb_check_for_lockdown(); + kdb_go_count = 0; if (reason == KDB_REASON_DEBUG) { /* special case below */ } else { - kdb_printf("\nEntering kdb (current=0x%p, pid %d) ", + kdb_printf("\nEntering kdb (current=0x%px, pid %d) ", kdb_current, kdb_current ? kdb_current->pid : 0); #if defined(CONFIG_SMP) kdb_printf("on processor %d ", raw_smp_processor_id()); @@ -1158,7 +1176,7 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, */ switch (db_result) { case KDB_DB_BPT: - kdb_printf("\nEntering kdb (0x%p, pid %d) ", + kdb_printf("\nEntering kdb (0x%px, pid %d) ", kdb_current, kdb_current->pid); #if defined(CONFIG_SMP) kdb_printf("on processor %d ", raw_smp_processor_id()); @@ -1200,11 +1218,13 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, instruction_pointer(regs)); kdb_dumpregs(regs); break; + case KDB_REASON_SYSTEM_NMI: + kdb_printf("due to System NonMaskable Interrupt\n"); + break; case KDB_REASON_NMI: kdb_printf("due to NonMaskable Interrupt @ " kdb_machreg_fmt "\n", instruction_pointer(regs)); - kdb_dumpregs(regs); break; case KDB_REASON_SSTEP: case KDB_REASON_BREAK: @@ -1238,20 +1258,18 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, */ kdb_nextline = 1; KDB_STATE_CLEAR(SUPPRESS); + kdb_grepping_flag = 0; + /* ensure the old search does not leak into '/' commands */ + kdb_grep_string[0] = '\0'; cmdbuf = cmd_cur; *cmdbuf = '\0'; *(cmd_hist[cmd_head]) = '\0'; do_full_getstr: -#if defined(CONFIG_SMP) + /* PROMPT can only be set if we have MEM_READ permission. */ snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"), raw_smp_processor_id()); -#else - snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT")); -#endif - if (defcmd_in_progress) - strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN); /* * Fetch command from keyboard @@ -1260,7 +1278,7 @@ do_full_getstr: if (*cmdbuf != '\n') { if (*cmdbuf < 32) { if (cmdptr == cmd_head) { - strncpy(cmd_hist[cmd_head], cmd_cur, + strscpy(cmd_hist[cmd_head], cmd_cur, CMD_BUFLEN); *(cmd_hist[cmd_head] + strlen(cmd_hist[cmd_head])-1) = '\0'; @@ -1270,7 +1288,7 @@ do_full_getstr: cmdbuf = cmd_cur; goto do_full_getstr; } else { - strncpy(cmd_hist[cmd_head], cmd_cur, + strscpy(cmd_hist[cmd_head], cmd_cur, CMD_BUFLEN); } @@ -1282,6 +1300,7 @@ do_full_getstr: cmdptr = cmd_head; diag = kdb_parse(cmdbuf); if (diag == KDB_NOTFOUND) { + drop_newline(cmdbuf); kdb_printf("Unknown kdb command: '%s'\n", cmdbuf); diag = 0; } @@ -1437,6 +1456,7 @@ static void kdb_md_line(const char *fmtstr, unsigned long addr, char cbuf[32]; char *c = cbuf; int i; + int j; unsigned long word; memset(cbuf, '\0', sizeof(cbuf)); @@ -1482,25 +1502,9 @@ static void kdb_md_line(const char *fmtstr, unsigned long addr, wc.word = word; #define printable_char(c) \ ({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; }) - switch (bytesperword) { - case 8: - *c++ = printable_char(*cp++); - *c++ = printable_char(*cp++); + for (j = 0; j < bytesperword; j++) *c++ = printable_char(*cp++); - *c++ = printable_char(*cp++); - addr += 4; - case 4: - *c++ = printable_char(*cp++); - *c++ = printable_char(*cp++); - addr += 2; - case 2: - *c++ = printable_char(*cp++); - addr++; - case 1: - *c++ = printable_char(*cp++); - addr++; - break; - } + addr += bytesperword; #undef printable_char } } @@ -1521,6 +1525,7 @@ static int kdb_md(int argc, const char **argv) int symbolic = 0; int valid = 0; int phys = 0; + int raw = 0; kdbgetintenv("MDCOUNT", &mdcount); kdbgetintenv("RADIX", &radix); @@ -1530,9 +1535,10 @@ static int kdb_md(int argc, const char **argv) repeat = mdcount * 16 / bytesperword; if (strcmp(argv[0], "mdr") == 0) { - if (argc != 2) + if (argc == 2 || (argc == 0 && last_addr != 0)) + valid = raw = 1; + else return KDB_ARGCOUNT; - valid = 1; } else if (isdigit(argv[0][2])) { bytesperword = (int)(argv[0][2] - '0'); if (bytesperword == 0) { @@ -1545,10 +1551,10 @@ static int kdb_md(int argc, const char **argv) if (!argv[0][3]) valid = 1; else if (argv[0][3] == 'c' && argv[0][4]) { - char *p; - repeat = simple_strtoul(argv[0] + 4, &p, 10); + if (kstrtouint(argv[0] + 4, 10, &repeat)) + return KDB_BADINT; mdcount = ((repeat * bytesperword) + 15) / 16; - valid = !*p; + valid = 1; } last_repeat = repeat; } else if (strcmp(argv[0], "md") == 0) @@ -1568,7 +1574,10 @@ static int kdb_md(int argc, const char **argv) radix = last_radix; bytesperword = last_bytesperword; repeat = last_repeat; - mdcount = ((repeat * bytesperword) + 15) / 16; + if (raw) + mdcount = repeat; + else + mdcount = ((repeat * bytesperword) + 15) / 16; } if (argc) { @@ -1585,7 +1594,10 @@ static int kdb_md(int argc, const char **argv) diag = kdbgetularg(argv[nextarg], &val); if (!diag) { mdcount = (int) val; - repeat = mdcount * 16 / bytesperword; + if (raw) + repeat = mdcount; + else + repeat = mdcount * 16 / bytesperword; } } if (argc >= nextarg+1) { @@ -1595,8 +1607,15 @@ static int kdb_md(int argc, const char **argv) } } - if (strcmp(argv[0], "mdr") == 0) - return kdb_mdr(addr, mdcount); + if (strcmp(argv[0], "mdr") == 0) { + int ret; + last_addr = addr; + ret = kdb_mdr(addr, mdcount); + last_addr += mdcount; + last_repeat = mdcount; + last_bytesperword = bytesperword; // to make REPEAT happy + return ret; + } switch (radix) { case 10: @@ -1918,10 +1937,14 @@ static int kdb_rm(int argc, const char **argv) */ static int kdb_sr(int argc, const char **argv) { + bool check_mask = + !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false); + if (argc != 1) return KDB_ARGCOUNT; + kdb_trap_printk++; - __handle_sysrq(*argv[1], false); + __handle_sysrq(*argv[1], check_mask); kdb_trap_printk--; return 0; @@ -1955,54 +1978,6 @@ static int kdb_ef(int argc, const char **argv) return 0; } -#if defined(CONFIG_MODULES) -/* - * kdb_lsmod - This function implements the 'lsmod' command. Lists - * currently loaded kernel modules. - * Mostly taken from userland lsmod. - */ -static int kdb_lsmod(int argc, const char **argv) -{ - struct module *mod; - - if (argc != 0) - return KDB_ARGCOUNT; - - kdb_printf("Module Size modstruct Used by\n"); - list_for_each_entry(mod, kdb_modules, list) { - if (mod->state == MODULE_STATE_UNFORMED) - continue; - - kdb_printf("%-20s%8u 0x%p ", mod->name, - mod->core_size, (void *)mod); -#ifdef CONFIG_MODULE_UNLOAD - kdb_printf("%4ld ", module_refcount(mod)); -#endif - if (mod->state == MODULE_STATE_GOING) - kdb_printf(" (Unloading)"); - else if (mod->state == MODULE_STATE_COMING) - kdb_printf(" (Loading)"); - else - kdb_printf(" (Live)"); - kdb_printf(" 0x%p", mod->module_core); - -#ifdef CONFIG_MODULE_UNLOAD - { - struct module_use *use; - kdb_printf(" [ "); - list_for_each_entry(use, &mod->source_list, - source_list) - kdb_printf("%s ", use->target->name); - kdb_printf("]\n"); - } -#endif - } - - return 0; -} - -#endif /* CONFIG_MODULES */ - /* * kdb_env - This function implements the 'env' command. Display the * current environment variables. @@ -2010,15 +1985,11 @@ static int kdb_lsmod(int argc, const char **argv) static int kdb_env(int argc, const char **argv) { - int i; - - for (i = 0; i < __nenv; i++) { - if (__env[i]) - kdb_printf("%s\n", __env[i]); - } + kdb_printenv(); if (KDB_DEBUG(MASK)) - kdb_printf("KDBFLAGS=0x%x\n", kdb_flags); + kdb_printf("KDBDEBUG=0x%x\n", + (kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT); return 0; } @@ -2037,22 +2008,17 @@ static int kdb_dmesg(int argc, const char **argv) int adjust = 0; int n = 0; int skip = 0; - struct kmsg_dumper dumper = { .active = 1 }; + struct kmsg_dump_iter iter; size_t len; char buf[201]; if (argc > 2) return KDB_ARGCOUNT; if (argc) { - char *cp; - lines = simple_strtol(argv[1], &cp, 0); - if (*cp) + if (kstrtoint(argv[1], 0, &lines)) lines = 0; - if (argc > 1) { - adjust = simple_strtoul(argv[2], &cp, 0); - if (*cp || adjust < 0) - adjust = 0; - } + if (argc > 1 && (kstrtoint(argv[2], 0, &adjust) || adjust < 0)) + adjust = 0; } /* disable LOGGING if set */ @@ -2062,8 +2028,8 @@ static int kdb_dmesg(int argc, const char **argv) kdb_set(2, setargs); } - kmsg_dump_rewind_nolock(&dumper); - while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL)) + kmsg_dump_rewind(&iter); + while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL)) n++; if (lines < 0) { @@ -2095,8 +2061,8 @@ static int kdb_dmesg(int argc, const char **argv) if (skip >= n || skip < 0) return 0; - kmsg_dump_rewind_nolock(&dumper); - while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) { + kmsg_dump_rewind(&iter); + while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) { if (skip) { skip--; continue; @@ -2112,32 +2078,6 @@ static int kdb_dmesg(int argc, const char **argv) return 0; } #endif /* CONFIG_PRINTK */ - -/* Make sure we balance enable/disable calls, must disable first. */ -static atomic_t kdb_nmi_disabled; - -static int kdb_disable_nmi(int argc, const char *argv[]) -{ - if (atomic_read(&kdb_nmi_disabled)) - return 0; - atomic_set(&kdb_nmi_disabled, 1); - arch_kgdb_ops.enable_nmi(0); - return 0; -} - -static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp) -{ - if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0)) - return -EINVAL; - arch_kgdb_ops.enable_nmi(1); - return 0; -} - -static const struct kernel_param_ops kdb_param_ops_enable_nmi = { - .set = kdb_param_enable_nmi, -}; -module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600); - /* * kdb_cpu - This function implements the 'cpu' command. * cpu [<cpunum>] @@ -2154,10 +2094,12 @@ static void kdb_cpu_status(void) for (start_cpu = -1, i = 0; i < NR_CPUS; i++) { if (!cpu_online(i)) { state = 'F'; /* cpu is offline */ + } else if (!kgdb_info[i].enter_kgdb) { + state = 'D'; /* cpu is online but unresponsive */ } else { state = ' '; /* cpu is responding to kdb */ - if (kdb_task_state_char(KDB_TSK(i)) == 'I') - state = 'I'; /* idle task */ + if (kdb_task_state_char(KDB_TSK(i)) == '-') + state = '-'; /* idle task */ } if (state != prev_state) { if (prev_state != '?') { @@ -2207,7 +2149,7 @@ static int kdb_cpu(int argc, const char **argv) /* * Validate cpunum */ - if ((cpunum > NR_CPUS) || !cpu_online(cpunum)) + if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb) return KDB_BADCPUNUM; dbg_switch_cpu = cpunum; @@ -2224,52 +2166,46 @@ static int kdb_cpu(int argc, const char **argv) void kdb_ps_suppressed(void) { int idle = 0, daemon = 0; - unsigned long mask_I = kdb_task_state_string("I"), - mask_M = kdb_task_state_string("M"); unsigned long cpu; const struct task_struct *p, *g; for_each_online_cpu(cpu) { - p = kdb_curr_task(cpu); - if (kdb_task_state(p, mask_I)) + p = curr_task(cpu); + if (kdb_task_state(p, "-")) ++idle; } - kdb_do_each_thread(g, p) { - if (kdb_task_state(p, mask_M)) + for_each_process_thread(g, p) { + if (kdb_task_state(p, "ims")) ++daemon; - } kdb_while_each_thread(g, p); + } if (idle || daemon) { if (idle) - kdb_printf("%d idle process%s (state I)%s\n", + kdb_printf("%d idle process%s (state -)%s\n", idle, idle == 1 ? "" : "es", daemon ? " and " : ""); if (daemon) - kdb_printf("%d sleeping system daemon (state M) " + kdb_printf("%d sleeping system daemon (state [ims]) " "process%s", daemon, daemon == 1 ? "" : "es"); kdb_printf(" suppressed,\nuse 'ps A' to see all.\n"); } } -/* - * kdb_ps - This function implements the 'ps' command which shows a - * list of the active processes. - * ps [DRSTCZEUIMA] All processes, optionally filtered by state - */ void kdb_ps1(const struct task_struct *p) { int cpu; unsigned long tmp; - if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long))) + if (!p || + copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long))) return; cpu = kdb_process_cpu(p); - kdb_printf("0x%p %8d %8d %d %4d %c 0x%p %c%s\n", + kdb_printf("0x%px %8d %8d %d %4d %c 0x%px %c%s\n", (void *)p, p->pid, p->parent->pid, kdb_task_has_cpu(p), kdb_process_cpu(p), kdb_task_state_char(p), (void *)(&p->thread), - p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ', + p == curr_task(raw_smp_processor_id()) ? '*' : ' ', p->comm); if (kdb_task_has_cpu(p)) { if (!KDB_TSK(cpu)) { @@ -2277,38 +2213,46 @@ void kdb_ps1(const struct task_struct *p) } else { if (KDB_TSK(cpu) != p) kdb_printf(" Error: does not match running " - "process table (0x%p)\n", KDB_TSK(cpu)); + "process table (0x%px)\n", KDB_TSK(cpu)); } } } +/* + * kdb_ps - This function implements the 'ps' command which shows a + * list of the active processes. + * + * ps [<state_chars>] Show processes, optionally selecting only those whose + * state character is found in <state_chars>. + */ static int kdb_ps(int argc, const char **argv) { struct task_struct *g, *p; - unsigned long mask, cpu; + const char *mask; + unsigned long cpu; if (argc == 0) kdb_ps_suppressed(); kdb_printf("%-*s Pid Parent [*] cpu State %-*s Command\n", (int)(2*sizeof(void *))+2, "Task Addr", (int)(2*sizeof(void *))+2, "Thread"); - mask = kdb_task_state_string(argc ? argv[1] : NULL); + mask = argc ? argv[1] : kdbgetenv("PS"); /* Run the active tasks first */ for_each_online_cpu(cpu) { if (KDB_FLAG(CMD_INTERRUPT)) return 0; - p = kdb_curr_task(cpu); + p = curr_task(cpu); if (kdb_task_state(p, mask)) kdb_ps1(p); } kdb_printf("\n"); /* Now the real tasks */ - kdb_do_each_thread(g, p) { + for_each_process_thread(g, p) { if (KDB_FLAG(CMD_INTERRUPT)) return 0; if (kdb_task_state(p, mask)) kdb_ps1(p); - } kdb_while_each_thread(g, p); + } return 0; } @@ -2361,21 +2305,20 @@ static int kdb_kgdb(int argc, const char **argv) static int kdb_help(int argc, const char **argv) { kdbtab_t *kt; - int i; kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description"); kdb_printf("-----------------------------" "-----------------------------\n"); - for_each_kdbcmd(kt, i) { + list_for_each_entry(kt, &kdb_cmds_head, list_node) { char *space = ""; if (KDB_FLAG(CMD_INTERRUPT)) return 0; - if (!kt->cmd_name) + if (!kdb_check_flags(kt->flags, kdb_cmd_enabled, true)) continue; - if (strlen(kt->cmd_usage) > 20) + if (strlen(kt->usage) > 20) space = "\n "; - kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name, - kt->cmd_usage, space, kt->cmd_help); + kdb_printf("%-15.15s %-20s%s%s\n", kt->name, + kt->usage, space, kt->help); } return 0; } @@ -2386,24 +2329,20 @@ static int kdb_help(int argc, const char **argv) static int kdb_kill(int argc, const char **argv) { long sig, pid; - char *endp; struct task_struct *p; - struct siginfo info; if (argc != 2) return KDB_ARGCOUNT; - sig = simple_strtol(argv[1], &endp, 0); - if (*endp) + if (kstrtol(argv[1], 0, &sig)) return KDB_BADINT; - if (sig >= 0) { + if ((sig >= 0) || !valid_signal(-sig)) { kdb_printf("Invalid signal parameter.<-signal>\n"); return 0; } sig = -sig; - pid = simple_strtol(argv[2], &endp, 0); - if (*endp) + if (kstrtol(argv[2], 0, &pid)) return KDB_BADINT; if (pid <= 0) { kdb_printf("Process ID must be large than 0.\n"); @@ -2417,50 +2356,10 @@ static int kdb_kill(int argc, const char **argv) return 0; } p = p->group_leader; - info.si_signo = sig; - info.si_errno = 0; - info.si_code = SI_USER; - info.si_pid = pid; /* same capabilities as process being signalled */ - info.si_uid = 0; /* kdb has root authority */ - kdb_send_sig_info(p, &info); + kdb_send_sig(p, sig); return 0; } -struct kdb_tm { - int tm_sec; /* seconds */ - int tm_min; /* minutes */ - int tm_hour; /* hours */ - int tm_mday; /* day of the month */ - int tm_mon; /* month */ - int tm_year; /* year */ -}; - -static void kdb_gmtime(struct timespec *tv, struct kdb_tm *tm) -{ - /* This will work from 1970-2099, 2100 is not a leap year */ - static int mon_day[] = { 31, 29, 31, 30, 31, 30, 31, - 31, 30, 31, 30, 31 }; - memset(tm, 0, sizeof(*tm)); - tm->tm_sec = tv->tv_sec % (24 * 60 * 60); - tm->tm_mday = tv->tv_sec / (24 * 60 * 60) + - (2 * 365 + 1); /* shift base from 1970 to 1968 */ - tm->tm_min = tm->tm_sec / 60 % 60; - tm->tm_hour = tm->tm_sec / 60 / 60; - tm->tm_sec = tm->tm_sec % 60; - tm->tm_year = 68 + 4*(tm->tm_mday / (4*365+1)); - tm->tm_mday %= (4*365+1); - mon_day[1] = 29; - while (tm->tm_mday >= mon_day[tm->tm_mon]) { - tm->tm_mday -= mon_day[tm->tm_mon]; - if (++tm->tm_mon == 12) { - tm->tm_mon = 0; - ++tm->tm_year; - mon_day[1] = 28; - } - } - ++tm->tm_mday; -} - /* * Most of this code has been lifted from kernel/timer.c::sys_sysinfo(). * I cannot call that code directly from kdb, it has an unconditional @@ -2468,10 +2367,10 @@ static void kdb_gmtime(struct timespec *tv, struct kdb_tm *tm) */ static void kdb_sysinfo(struct sysinfo *val) { - struct timespec uptime; - do_posix_clock_monotonic_gettime(&uptime); + u64 uptime = ktime_get_mono_fast_ns(); + memset(val, 0, sizeof(*val)); - val->uptime = uptime.tv_sec; + val->uptime = div_u64(uptime, NSEC_PER_SEC); val->loads[0] = avenrun[0]; val->loads[1] = avenrun[1]; val->loads[2] = avenrun[2]; @@ -2486,8 +2385,7 @@ static void kdb_sysinfo(struct sysinfo *val) */ static int kdb_summary(int argc, const char **argv) { - struct timespec now; - struct kdb_tm tm; + time64_t now; struct sysinfo val; if (argc) @@ -2499,40 +2397,28 @@ static int kdb_summary(int argc, const char **argv) kdb_printf("machine %s\n", init_uts_ns.name.machine); kdb_printf("nodename %s\n", init_uts_ns.name.nodename); kdb_printf("domainname %s\n", init_uts_ns.name.domainname); - kdb_printf("ccversion %s\n", __stringify(CCVERSION)); - - now = __current_kernel_time(); - kdb_gmtime(&now, &tm); - kdb_printf("date %04d-%02d-%02d %02d:%02d:%02d " - "tz_minuteswest %d\n", - 1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday, - tm.tm_hour, tm.tm_min, tm.tm_sec, - sys_tz.tz_minuteswest); + now = __ktime_get_real_seconds(); + kdb_printf("date %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest); kdb_sysinfo(&val); kdb_printf("uptime "); if (val.uptime > (24*60*60)) { int days = val.uptime / (24*60*60); val.uptime %= (24*60*60); - kdb_printf("%d day%s ", days, days == 1 ? "" : "s"); + kdb_printf("%d day%s ", days, str_plural(days)); } kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60); - /* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */ - -#define LOAD_INT(x) ((x) >> FSHIFT) -#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) kdb_printf("load avg %ld.%02ld %ld.%02ld %ld.%02ld\n", LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]), LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]), LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2])); -#undef LOAD_INT -#undef LOAD_FRAC + /* Display in kilobytes */ #define K(x) ((x) << (PAGE_SHIFT - 10)) kdb_printf("\nMemTotal: %8lu kB\nMemFree: %8lu kB\n" "Buffers: %8lu kB\n", - val.totalram, val.freeram, val.bufferram); + K(val.totalram), K(val.freeram), K(val.bufferram)); return 0; } @@ -2566,7 +2452,7 @@ static int kdb_per_cpu(int argc, const char **argv) diag = kdbgetularg(argv[3], &whichcpu); if (diag) return diag; - if (!cpu_online(whichcpu)) { + if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) { kdb_printf("cpu %ld is not online\n", whichcpu); return KDB_BADCPUNUM; } @@ -2625,216 +2511,268 @@ static int kdb_grep_help(int argc, const char **argv) return 0; } -/* - * kdb_register_repeat - This function is used to register a kernel - * debugger command. - * Inputs: - * cmd Command name - * func Function to execute the command - * usage A simple usage string showing arguments - * help A simple help string describing command - * repeat Does the command auto repeat on enter? - * Returns: - * zero for success, one if a duplicate command. +/** + * kdb_register() - This function is used to register a kernel debugger + * command. + * @cmd: pointer to kdb command + * + * Note that it's the job of the caller to keep the memory for the cmd + * allocated until unregister is called. */ -#define kdb_command_extend 50 /* arbitrary */ -int kdb_register_repeat(char *cmd, - kdb_func_t func, - char *usage, - char *help, - short minlen, - kdb_repeat_t repeat) +int kdb_register(kdbtab_t *cmd) { - int i; kdbtab_t *kp; - /* - * Brute force method to determine duplicates - */ - for_each_kdbcmd(kp, i) { - if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) { - kdb_printf("Duplicate kdb command registered: " - "%s, func %p help %s\n", cmd, func, help); - return 1; - } - } - - /* - * Insert command into first available location in table - */ - for_each_kdbcmd(kp, i) { - if (kp->cmd_name == NULL) - break; - } - - if (i >= kdb_max_commands) { - kdbtab_t *new = kmalloc((kdb_max_commands - KDB_BASE_CMD_MAX + - kdb_command_extend) * sizeof(*new), GFP_KDB); - if (!new) { - kdb_printf("Could not allocate new kdb_command " - "table\n"); + list_for_each_entry(kp, &kdb_cmds_head, list_node) { + if (strcmp(kp->name, cmd->name) == 0) { + kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n", + cmd->name, cmd->func, cmd->help); return 1; } - if (kdb_commands) { - memcpy(new, kdb_commands, - (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new)); - kfree(kdb_commands); - } - memset(new + kdb_max_commands - KDB_BASE_CMD_MAX, 0, - kdb_command_extend * sizeof(*new)); - kdb_commands = new; - kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX; - kdb_max_commands += kdb_command_extend; } - kp->cmd_name = cmd; - kp->cmd_func = func; - kp->cmd_usage = usage; - kp->cmd_help = help; - kp->cmd_flags = 0; - kp->cmd_minlen = minlen; - kp->cmd_repeat = repeat; - + list_add_tail(&cmd->list_node, &kdb_cmds_head); return 0; } -EXPORT_SYMBOL_GPL(kdb_register_repeat); - +EXPORT_SYMBOL_GPL(kdb_register); -/* - * kdb_register - Compatibility register function for commands that do - * not need to specify a repeat state. Equivalent to - * kdb_register_repeat with KDB_REPEAT_NONE. - * Inputs: - * cmd Command name - * func Function to execute the command - * usage A simple usage string showing arguments - * help A simple help string describing command - * Returns: - * zero for success, one if a duplicate command. +/** + * kdb_register_table() - This function is used to register a kdb command + * table. + * @kp: pointer to kdb command table + * @len: length of kdb command table */ -int kdb_register(char *cmd, - kdb_func_t func, - char *usage, - char *help, - short minlen) +void kdb_register_table(kdbtab_t *kp, size_t len) { - return kdb_register_repeat(cmd, func, usage, help, minlen, - KDB_REPEAT_NONE); + while (len--) { + list_add_tail(&kp->list_node, &kdb_cmds_head); + kp++; + } } -EXPORT_SYMBOL_GPL(kdb_register); -/* - * kdb_unregister - This function is used to unregister a kernel - * debugger command. It is generally called when a module which - * implements kdb commands is unloaded. - * Inputs: - * cmd Command name - * Returns: - * zero for success, one command not registered. +/** + * kdb_unregister() - This function is used to unregister a kernel debugger + * command. It is generally called when a module which + * implements kdb command is unloaded. + * @cmd: pointer to kdb command */ -int kdb_unregister(char *cmd) +void kdb_unregister(kdbtab_t *cmd) { - int i; - kdbtab_t *kp; - - /* - * find the command. - */ - for_each_kdbcmd(kp, i) { - if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) { - kp->cmd_name = NULL; - return 0; - } - } - - /* Couldn't find it. */ - return 1; + list_del(&cmd->list_node); } EXPORT_SYMBOL_GPL(kdb_unregister); -/* Initialize the kdb command table. */ -static void __init kdb_inittab(void) -{ - int i; - kdbtab_t *kp; - - for_each_kdbcmd(kp, i) - kp->cmd_name = NULL; - - kdb_register_repeat("md", kdb_md, "<vaddr>", - "Display Memory Contents, also mdWcN, e.g. md8c1", 1, - KDB_REPEAT_NO_ARGS); - kdb_register_repeat("mdr", kdb_md, "<vaddr> <bytes>", - "Display Raw Memory", 0, KDB_REPEAT_NO_ARGS); - kdb_register_repeat("mdp", kdb_md, "<paddr> <bytes>", - "Display Physical Memory", 0, KDB_REPEAT_NO_ARGS); - kdb_register_repeat("mds", kdb_md, "<vaddr>", - "Display Memory Symbolically", 0, KDB_REPEAT_NO_ARGS); - kdb_register_repeat("mm", kdb_mm, "<vaddr> <contents>", - "Modify Memory Contents", 0, KDB_REPEAT_NO_ARGS); - kdb_register_repeat("go", kdb_go, "[<vaddr>]", - "Continue Execution", 1, KDB_REPEAT_NONE); - kdb_register_repeat("rd", kdb_rd, "", - "Display Registers", 0, KDB_REPEAT_NONE); - kdb_register_repeat("rm", kdb_rm, "<reg> <contents>", - "Modify Registers", 0, KDB_REPEAT_NONE); - kdb_register_repeat("ef", kdb_ef, "<vaddr>", - "Display exception frame", 0, KDB_REPEAT_NONE); - kdb_register_repeat("bt", kdb_bt, "[<vaddr>]", - "Stack traceback", 1, KDB_REPEAT_NONE); - kdb_register_repeat("btp", kdb_bt, "<pid>", - "Display stack for process <pid>", 0, KDB_REPEAT_NONE); - kdb_register_repeat("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]", - "Backtrace all processes matching state flag", 0, KDB_REPEAT_NONE); - kdb_register_repeat("btc", kdb_bt, "", - "Backtrace current process on each cpu", 0, KDB_REPEAT_NONE); - kdb_register_repeat("btt", kdb_bt, "<vaddr>", - "Backtrace process given its struct task address", 0, - KDB_REPEAT_NONE); - kdb_register_repeat("env", kdb_env, "", - "Show environment variables", 0, KDB_REPEAT_NONE); - kdb_register_repeat("set", kdb_set, "", - "Set environment variables", 0, KDB_REPEAT_NONE); - kdb_register_repeat("help", kdb_help, "", - "Display Help Message", 1, KDB_REPEAT_NONE); - kdb_register_repeat("?", kdb_help, "", - "Display Help Message", 0, KDB_REPEAT_NONE); - kdb_register_repeat("cpu", kdb_cpu, "<cpunum>", - "Switch to new cpu", 0, KDB_REPEAT_NONE); - kdb_register_repeat("kgdb", kdb_kgdb, "", - "Enter kgdb mode", 0, KDB_REPEAT_NONE); - kdb_register_repeat("ps", kdb_ps, "[<flags>|A]", - "Display active task list", 0, KDB_REPEAT_NONE); - kdb_register_repeat("pid", kdb_pid, "<pidnum>", - "Switch to another task", 0, KDB_REPEAT_NONE); - kdb_register_repeat("reboot", kdb_reboot, "", - "Reboot the machine immediately", 0, KDB_REPEAT_NONE); +static kdbtab_t maintab[] = { + { .name = "md", + .func = kdb_md, + .usage = "<vaddr>", + .help = "Display Memory Contents, also mdWcN, e.g. md8c1", + .minlen = 1, + .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS, + }, + { .name = "mdr", + .func = kdb_md, + .usage = "<vaddr> <bytes>", + .help = "Display Raw Memory", + .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS, + }, + { .name = "mdp", + .func = kdb_md, + .usage = "<paddr> <bytes>", + .help = "Display Physical Memory", + .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS, + }, + { .name = "mds", + .func = kdb_md, + .usage = "<vaddr>", + .help = "Display Memory Symbolically", + .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS, + }, + { .name = "mm", + .func = kdb_mm, + .usage = "<vaddr> <contents>", + .help = "Modify Memory Contents", + .flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS, + }, + { .name = "go", + .func = kdb_go, + .usage = "[<vaddr>]", + .help = "Continue Execution", + .minlen = 1, + .flags = KDB_ENABLE_REG_WRITE | + KDB_ENABLE_ALWAYS_SAFE_NO_ARGS, + }, + { .name = "rd", + .func = kdb_rd, + .usage = "", + .help = "Display Registers", + .flags = KDB_ENABLE_REG_READ, + }, + { .name = "rm", + .func = kdb_rm, + .usage = "<reg> <contents>", + .help = "Modify Registers", + .flags = KDB_ENABLE_REG_WRITE, + }, + { .name = "ef", + .func = kdb_ef, + .usage = "<vaddr>", + .help = "Display exception frame", + .flags = KDB_ENABLE_MEM_READ, + }, + { .name = "bt", + .func = kdb_bt, + .usage = "[<vaddr>]", + .help = "Stack traceback", + .minlen = 1, + .flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS, + }, + { .name = "btp", + .func = kdb_bt, + .usage = "<pid>", + .help = "Display stack for process <pid>", + .flags = KDB_ENABLE_INSPECT, + }, + { .name = "bta", + .func = kdb_bt, + .usage = "[<state_chars>|A]", + .help = "Backtrace all processes whose state matches", + .flags = KDB_ENABLE_INSPECT, + }, + { .name = "btc", + .func = kdb_bt, + .usage = "", + .help = "Backtrace current process on each cpu", + .flags = KDB_ENABLE_INSPECT, + }, + { .name = "btt", + .func = kdb_bt, + .usage = "<vaddr>", + .help = "Backtrace process given its struct task address", + .flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS, + }, + { .name = "env", + .func = kdb_env, + .usage = "", + .help = "Show environment variables", + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, + { .name = "set", + .func = kdb_set, + .usage = "", + .help = "Set environment variables", + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, + { .name = "help", + .func = kdb_help, + .usage = "", + .help = "Display Help Message", + .minlen = 1, + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, + { .name = "?", + .func = kdb_help, + .usage = "", + .help = "Display Help Message", + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, + { .name = "cpu", + .func = kdb_cpu, + .usage = "<cpunum>", + .help = "Switch to new cpu", + .flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS, + }, + { .name = "kgdb", + .func = kdb_kgdb, + .usage = "", + .help = "Enter kgdb mode", + .flags = 0, + }, + { .name = "ps", + .func = kdb_ps, + .usage = "[<state_chars>|A]", + .help = "Display active task list", + .flags = KDB_ENABLE_INSPECT, + }, + { .name = "pid", + .func = kdb_pid, + .usage = "<pidnum>", + .help = "Switch to another task", + .flags = KDB_ENABLE_INSPECT, + }, + { .name = "reboot", + .func = kdb_reboot, + .usage = "", + .help = "Reboot the machine immediately", + .flags = KDB_ENABLE_REBOOT, + }, #if defined(CONFIG_MODULES) - kdb_register_repeat("lsmod", kdb_lsmod, "", - "List loaded kernel modules", 0, KDB_REPEAT_NONE); + { .name = "lsmod", + .func = kdb_lsmod, + .usage = "", + .help = "List loaded kernel modules", + .flags = KDB_ENABLE_INSPECT, + }, #endif #if defined(CONFIG_MAGIC_SYSRQ) - kdb_register_repeat("sr", kdb_sr, "<key>", - "Magic SysRq key", 0, KDB_REPEAT_NONE); + { .name = "sr", + .func = kdb_sr, + .usage = "<key>", + .help = "Magic SysRq key", + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, #endif #if defined(CONFIG_PRINTK) - kdb_register_repeat("dmesg", kdb_dmesg, "[lines]", - "Display syslog buffer", 0, KDB_REPEAT_NONE); + { .name = "dmesg", + .func = kdb_dmesg, + .usage = "[lines]", + .help = "Display syslog buffer", + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, #endif - if (arch_kgdb_ops.enable_nmi) { - kdb_register_repeat("disable_nmi", kdb_disable_nmi, "", - "Disable NMI entry to KDB", 0, KDB_REPEAT_NONE); - } - kdb_register_repeat("defcmd", kdb_defcmd, "name \"usage\" \"help\"", - "Define a set of commands, down to endefcmd", 0, KDB_REPEAT_NONE); - kdb_register_repeat("kill", kdb_kill, "<-signal> <pid>", - "Send a signal to a process", 0, KDB_REPEAT_NONE); - kdb_register_repeat("summary", kdb_summary, "", - "Summarize the system", 4, KDB_REPEAT_NONE); - kdb_register_repeat("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]", - "Display per_cpu variables", 3, KDB_REPEAT_NONE); - kdb_register_repeat("grephelp", kdb_grep_help, "", - "Display help on | grep", 0, KDB_REPEAT_NONE); + { .name = "defcmd", + .func = kdb_defcmd, + .usage = "name \"usage\" \"help\"", + .help = "Define a set of commands, down to endefcmd", + /* + * Macros are always safe because when executed each + * internal command re-enters kdb_parse() and is safety + * checked individually. + */ + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, + { .name = "kill", + .func = kdb_kill, + .usage = "<-signal> <pid>", + .help = "Send a signal to a process", + .flags = KDB_ENABLE_SIGNAL, + }, + { .name = "summary", + .func = kdb_summary, + .usage = "", + .help = "Summarize the system", + .minlen = 4, + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, + { .name = "per_cpu", + .func = kdb_per_cpu, + .usage = "<sym> [<bytes>] [<cpu>]", + .help = "Display per_cpu variables", + .minlen = 3, + .flags = KDB_ENABLE_MEM_READ, + }, + { .name = "grephelp", + .func = kdb_grep_help, + .usage = "", + .help = "Display help on | grep", + .flags = KDB_ENABLE_ALWAYS_SAFE, + }, +}; + +/* Initialize the kdb command table. */ +static void __init kdb_inittab(void) +{ + kdb_register_table(maintab, ARRAY_SIZE(maintab)); } /* Execute any commands defined in kdb_cmds. */ diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h index 7afd3c8c41d5..a2fc7d2bc9fc 100644 --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -64,7 +64,7 @@ /* * KDB_MAXBPT describes the total number of breakpoints - * supported by this architecure. + * supported by this architecture. */ #define KDB_MAXBPT 16 @@ -83,7 +83,7 @@ typedef struct __ksymtab { unsigned long sym_start; unsigned long sym_end; } kdb_symtab_t; -extern int kallsyms_symbol_next(char *prefix_name, int flag); +extern int kallsyms_symbol_next(char *prefix_name, int flag, int buf_size); extern int kallsyms_symbol_complete(char *prefix_name, int max_len); /* Exported Symbols for kernel loadable modules to use. */ @@ -109,8 +109,8 @@ extern int kdbgetaddrarg(int, const char **, int*, unsigned long *, long *, char **); extern int kdbgetsymval(const char *, kdb_symtab_t *); extern int kdbnearsym(unsigned long, kdb_symtab_t *); -extern void kdbnearsym_cleanup(void); extern char *kdb_strdup(const char *str, gfp_t type); +extern char *kdb_strdup_dequote(const char *str, gfp_t type); extern void kdb_symbol_print(unsigned long, const kdb_symtab_t *, unsigned int); /* Routine for debugging the debugger state. */ @@ -132,7 +132,6 @@ extern int kdb_state; #define KDB_STATE_PAGER 0x00000400 /* pager is available */ #define KDB_STATE_GO_SWITCH 0x00000800 /* go is switching * back to initial cpu */ -#define KDB_STATE_PRINTF_LOCK 0x00001000 /* Holds kdb_printf lock */ #define KDB_STATE_WAIT_IPI 0x00002000 /* Waiting for kdb_ipi() NMI */ #define KDB_STATE_RECURSE 0x00004000 /* Recursive entry to kdb */ #define KDB_STATE_IP_ADJUSTED 0x00008000 /* Restart IP has been @@ -166,18 +165,7 @@ typedef struct _kdb_bp { #ifdef CONFIG_KGDB_KDB extern kdb_bp_t kdb_breakpoints[/* KDB_MAXBPT */]; -/* The KDB shell command table */ -typedef struct _kdbtab { - char *cmd_name; /* Command name */ - kdb_func_t cmd_func; /* Function to execute command */ - char *cmd_usage; /* Usage String for this command */ - char *cmd_help; /* Help message for this command */ - short cmd_flags; /* Parsing flags */ - short cmd_minlen; /* Minimum legal # command - * chars required */ - kdb_repeat_t cmd_repeat; /* Does command auto repeat on enter? */ -} kdbtab_t; - +extern void kdb_register_table(kdbtab_t *kp, size_t len); extern int kdb_bt(int, const char **); /* KDB display back trace */ /* KDB breakpoint management functions */ @@ -197,20 +185,18 @@ extern int kdb_main_loop(kdb_reason_t, kdb_reason_t, /* Miscellaneous functions and data areas */ extern int kdb_grepping_flag; +#define KDB_GREPPING_FLAG_SEARCH 0x8000 extern char kdb_grep_string[]; +#define KDB_GREP_STRLEN 256 extern int kdb_grep_leading; extern int kdb_grep_trailing; extern char *kdb_cmds[]; -extern unsigned long kdb_task_state_string(const char *); extern char kdb_task_state_char (const struct task_struct *); -extern unsigned long kdb_task_state(const struct task_struct *p, - unsigned long mask); +extern bool kdb_task_state(const struct task_struct *p, const char *mask); extern void kdb_ps_suppressed(void); extern void kdb_ps1(const struct task_struct *p); -extern void kdb_print_nameval(const char *name, unsigned long val); -extern void kdb_send_sig_info(struct task_struct *p, struct siginfo *info); -extern void kdb_meminfo_proc_show(void); -extern char *kdb_getstr(char *, size_t, char *); +extern char kdb_getchar(void); +extern char *kdb_getstr(char *, size_t, const char *); extern void kdb_gdb_state_pass(char *buf); /* Defines for kdb_symbol_print */ @@ -225,22 +211,12 @@ extern void kdb_gdb_state_pass(char *buf); #define KDB_TSK(cpu) kgdb_info[cpu].task #define KDB_TSKREGS(cpu) kgdb_info[cpu].debuggerinfo -extern struct task_struct *kdb_curr_task(int); - #define kdb_task_has_cpu(p) (task_curr(p)) -/* Simplify coexistence with NPTL */ -#define kdb_do_each_thread(g, p) do_each_thread(g, p) -#define kdb_while_each_thread(g, p) while_each_thread(g, p) - -#define GFP_KDB (in_interrupt() ? GFP_ATOMIC : GFP_KERNEL) - -extern void *debug_kmalloc(size_t size, gfp_t flags); -extern void debug_kfree(void *); -extern void debug_kusage(void); +#define GFP_KDB (in_dbg_master() ? GFP_ATOMIC : GFP_KERNEL) -extern void kdb_set_current_task(struct task_struct *); extern struct task_struct *kdb_current_task; +extern struct pt_regs *kdb_current_regs; #ifdef CONFIG_KDB_KEYBOARD extern void kdb_kbd_cleanup_state(void); @@ -248,13 +224,19 @@ extern void kdb_kbd_cleanup_state(void); #define kdb_kbd_cleanup_state() #endif /* ! CONFIG_KDB_KEYBOARD */ -#ifdef CONFIG_MODULES -extern struct list_head *kdb_modules; -#endif /* CONFIG_MODULES */ - extern char kdb_prompt_str[]; #define KDB_WORD_SIZE ((int)sizeof(unsigned long)) #endif /* CONFIG_KGDB_KDB */ + +#define kdb_func_printf(format, args...) \ + kdb_printf("%s: " format, __func__, ## args) + +#define kdb_dbg_printf(mask, format, args...) \ + do { \ + if (KDB_DEBUG(mask)) \ + kdb_func_printf(format, ## args); \ + } while (0) + #endif /* !_KDBPRIVATE_H */ diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index d35cc2d3a4cc..56f7b906e7cc 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -10,7 +10,6 @@ * 03/02/13 added new 2.5 kallsyms <xavier.bru@bull.net> */ -#include <stdarg.h> #include <linux/types.h> #include <linux/sched.h> #include <linux/mm.h> @@ -18,13 +17,14 @@ #include <linux/stddef.h> #include <linux/vmalloc.h> #include <linux/ptrace.h> -#include <linux/module.h> #include <linux/highmem.h> #include <linux/hardirq.h> #include <linux/delay.h> #include <linux/uaccess.h> #include <linux/kdb.h> #include <linux/slab.h> +#include <linux/string.h> +#include <linux/ctype.h> #include "kdb_private.h" /* @@ -39,68 +39,61 @@ */ int kdbgetsymval(const char *symname, kdb_symtab_t *symtab) { - if (KDB_DEBUG(AR)) - kdb_printf("kdbgetsymval: symname=%s, symtab=%p\n", symname, - symtab); + kdb_dbg_printf(AR, "symname=%s, symtab=%px\n", symname, symtab); memset(symtab, 0, sizeof(*symtab)); symtab->sym_start = kallsyms_lookup_name(symname); if (symtab->sym_start) { - if (KDB_DEBUG(AR)) - kdb_printf("kdbgetsymval: returns 1, " - "symtab->sym_start=0x%lx\n", - symtab->sym_start); + kdb_dbg_printf(AR, "returns 1, symtab->sym_start=0x%lx\n", + symtab->sym_start); return 1; } - if (KDB_DEBUG(AR)) - kdb_printf("kdbgetsymval: returns 0\n"); + kdb_dbg_printf(AR, "returns 0\n"); return 0; } EXPORT_SYMBOL(kdbgetsymval); -static char *kdb_name_table[100]; /* arbitrary size */ - -/* - * kdbnearsym - Return the name of the symbol with the nearest address - * less than 'addr'. +/** + * kdbnearsym() - Return the name of the symbol with the nearest address + * less than @addr. + * @addr: Address to check for near symbol + * @symtab: Structure to receive results * - * Parameters: - * addr Address to check for symbol near - * symtab Structure to receive results - * Returns: - * 0 No sections contain this address, symtab zero filled - * 1 Address mapped to module/symbol/section, data in symtab - * Remarks: - * 2.6 kallsyms has a "feature" where it unpacks the name into a - * string. If that string is reused before the caller expects it - * then the caller sees its string change without warning. To - * avoid cluttering up the main kdb code with lots of kdb_strdup, - * tests and kfree calls, kdbnearsym maintains an LRU list of the - * last few unique strings. The list is sized large enough to - * hold active strings, no kdb caller of kdbnearsym makes more - * than ~20 later calls before using a saved value. + * WARNING: This function may return a pointer to a single statically + * allocated buffer (namebuf). kdb's unusual calling context (single + * threaded, all other CPUs halted) provides us sufficient locking for + * this to be safe. The only constraint imposed by the static buffer is + * that the caller must consume any previous reply prior to another call + * to lookup a new symbol. + * + * Note that, strictly speaking, some architectures may re-enter the kdb + * trap if the system turns out to be very badly damaged and this breaks + * the single-threaded assumption above. In these circumstances successful + * continuation and exit from the inner trap is unlikely to work and any + * user attempting this receives a prominent warning before being allowed + * to progress. In these circumstances we remain memory safe because + * namebuf[KSYM_NAME_LEN-1] will never change from '\0' although we do + * tolerate the possibility of garbled symbol display from the outer kdb + * trap. + * + * Return: + * * 0 - No sections contain this address, symtab zero filled + * * 1 - Address mapped to module/symbol/section, data in symtab */ int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab) { int ret = 0; unsigned long symbolsize = 0; unsigned long offset = 0; -#define knt1_size 128 /* must be >= kallsyms table size */ - char *knt1 = NULL; + static char namebuf[KSYM_NAME_LEN]; - if (KDB_DEBUG(AR)) - kdb_printf("kdbnearsym: addr=0x%lx, symtab=%p\n", addr, symtab); + kdb_dbg_printf(AR, "addr=0x%lx, symtab=%px\n", addr, symtab); memset(symtab, 0, sizeof(*symtab)); if (addr < 4096) goto out; - knt1 = debug_kmalloc(knt1_size, GFP_ATOMIC); - if (!knt1) { - kdb_printf("kdbnearsym: addr=0x%lx cannot kmalloc knt1\n", - addr); - goto out; - } + symtab->sym_name = kallsyms_lookup(addr, &symbolsize , &offset, - (char **)(&symtab->mod_name), knt1); + (char **)(&symtab->mod_name), namebuf); if (offset > 8*1024*1024) { symtab->sym_name = NULL; addr = offset = symbolsize = 0; @@ -109,66 +102,14 @@ int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab) symtab->sym_end = symtab->sym_start + symbolsize; ret = symtab->sym_name != NULL && *(symtab->sym_name) != '\0'; - if (ret) { - int i; - /* Another 2.6 kallsyms "feature". Sometimes the sym_name is - * set but the buffer passed into kallsyms_lookup is not used, - * so it contains garbage. The caller has to work out which - * buffer needs to be saved. - * - * What was Rusty smoking when he wrote that code? - */ - if (symtab->sym_name != knt1) { - strncpy(knt1, symtab->sym_name, knt1_size); - knt1[knt1_size-1] = '\0'; - } - for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) { - if (kdb_name_table[i] && - strcmp(kdb_name_table[i], knt1) == 0) - break; - } - if (i >= ARRAY_SIZE(kdb_name_table)) { - debug_kfree(kdb_name_table[0]); - memcpy(kdb_name_table, kdb_name_table+1, - sizeof(kdb_name_table[0]) * - (ARRAY_SIZE(kdb_name_table)-1)); - } else { - debug_kfree(knt1); - knt1 = kdb_name_table[i]; - memcpy(kdb_name_table+i, kdb_name_table+i+1, - sizeof(kdb_name_table[0]) * - (ARRAY_SIZE(kdb_name_table)-i-1)); - } - i = ARRAY_SIZE(kdb_name_table) - 1; - kdb_name_table[i] = knt1; - symtab->sym_name = kdb_name_table[i]; - knt1 = NULL; - } - if (symtab->mod_name == NULL) symtab->mod_name = "kernel"; - if (KDB_DEBUG(AR)) - kdb_printf("kdbnearsym: returns %d symtab->sym_start=0x%lx, " - "symtab->mod_name=%p, symtab->sym_name=%p (%s)\n", ret, - symtab->sym_start, symtab->mod_name, symtab->sym_name, - symtab->sym_name); - + kdb_dbg_printf(AR, "returns %d symtab->sym_start=0x%lx, symtab->mod_name=%px, symtab->sym_name=%px (%s)\n", + ret, symtab->sym_start, symtab->mod_name, symtab->sym_name, symtab->sym_name); out: - debug_kfree(knt1); return ret; } -void kdbnearsym_cleanup(void) -{ - int i; - for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) { - if (kdb_name_table[i]) { - debug_kfree(kdb_name_table[i]); - kdb_name_table[i] = NULL; - } - } -} - static char ks_namebuf[KSYM_NAME_LEN+1], ks_namebuf_prev[KSYM_NAME_LEN+1]; /* @@ -192,7 +133,7 @@ int kallsyms_symbol_complete(char *prefix_name, int max_len) while ((name = kdb_walk_kallsyms(&pos))) { if (strncmp(name, prefix_name, prefix_len) == 0) { - strcpy(ks_namebuf, name); + strscpy(ks_namebuf, name, sizeof(ks_namebuf)); /* Work out the longest name that matches the prefix */ if (++number == 1) { prev_len = min_t(int, max_len-1, @@ -221,11 +162,13 @@ int kallsyms_symbol_complete(char *prefix_name, int max_len) * Parameters: * prefix_name prefix of a symbol name to lookup * flag 0 means search from the head, 1 means continue search. + * buf_size maximum length that can be written to prefix_name + * buffer * Returns: * 1 if a symbol matches the given prefix. * 0 if no string found */ -int kallsyms_symbol_next(char *prefix_name, int flag) +int kallsyms_symbol_next(char *prefix_name, int flag, int buf_size) { int prefix_len = strlen(prefix_name); static loff_t pos; @@ -235,10 +178,8 @@ int kallsyms_symbol_next(char *prefix_name, int flag) pos = 0; while ((name = kdb_walk_kallsyms(&pos))) { - if (strncmp(name, prefix_name, prefix_len) == 0) { - strncpy(prefix_name, name, strlen(name)+1); - return 1; - } + if (!strncmp(name, prefix_name, prefix_len)) + return strscpy(prefix_name, name, buf_size); } return 0; } @@ -306,11 +247,41 @@ void kdb_symbol_print(unsigned long addr, const kdb_symtab_t *symtab_p, */ char *kdb_strdup(const char *str, gfp_t type) { - int n = strlen(str)+1; + size_t n = strlen(str) + 1; char *s = kmalloc(n, type); if (!s) return NULL; - return strcpy(s, str); + memcpy(s, str, n); + return s; +} + +/* + * kdb_strdup_dequote - same as kdb_strdup(), but trims surrounding quotes from + * the input string if present. + * Remarks: + * Quotes are only removed if there is both a leading and a trailing quote. + */ +char *kdb_strdup_dequote(const char *str, gfp_t type) +{ + size_t len = strlen(str); + char *s; + + if (str[0] == '"' && len > 1 && str[len - 1] == '"') { + /* trim both leading and trailing quotes */ + str++; + len -= 2; + } + + len++; /* add space for NUL terminator */ + + s = kmalloc(len, type); + if (!s) + return NULL; + + memcpy(s, str, len - 1); + s[len - 1] = '\0'; + + return s; } /* @@ -325,10 +296,10 @@ char *kdb_strdup(const char *str, gfp_t type) */ int kdb_getarea_size(void *res, unsigned long addr, size_t size) { - int ret = probe_kernel_read((char *)res, (char *)addr, size); + int ret = copy_from_kernel_nofault((char *)res, (char *)addr, size); if (ret) { if (!KDB_STATE(SUPPRESS)) { - kdb_printf("kdb_getarea: Bad address 0x%lx\n", addr); + kdb_func_printf("Bad address 0x%lx\n", addr); KDB_STATE_SET(SUPPRESS); } ret = KDB_BADADDR; @@ -350,10 +321,10 @@ int kdb_getarea_size(void *res, unsigned long addr, size_t size) */ int kdb_putarea_size(unsigned long addr, void *res, size_t size) { - int ret = probe_kernel_read((char *)addr, (char *)res, size); + int ret = copy_to_kernel_nofault((char *)addr, (char *)res, size); if (ret) { if (!KDB_STATE(SUPPRESS)) { - kdb_printf("kdb_putarea: Bad address 0x%lx\n", addr); + kdb_func_printf("Bad address 0x%lx\n", addr); KDB_STATE_SET(SUPPRESS); } ret = KDB_BADADDR; @@ -365,7 +336,7 @@ int kdb_putarea_size(unsigned long addr, void *res, size_t size) /* * kdb_getphys - Read data from a physical address. Validate the - * address is in range, use kmap_atomic() to get data + * address is in range, use kmap_local_page() to get data * similar to kdb_getarea() - but for phys addresses * Inputs: * res Pointer to the word to receive the result @@ -384,9 +355,9 @@ static int kdb_getphys(void *res, unsigned long addr, size_t size) if (!pfn_valid(pfn)) return 1; page = pfn_to_page(pfn); - vaddr = kmap_atomic(page); + vaddr = kmap_local_page(page); memcpy(res, vaddr + (addr & (PAGE_SIZE - 1)), size); - kunmap_atomic(vaddr); + kunmap_local(vaddr); return 0; } @@ -432,10 +403,10 @@ int kdb_getphysword(unsigned long *word, unsigned long addr, size_t size) *word = w8; break; } - /* drop through */ + fallthrough; default: diag = KDB_BADWIDTH; - kdb_printf("kdb_getphysword: bad width %ld\n", (long) size); + kdb_func_printf("bad width %zu\n", size); } return diag; } @@ -481,10 +452,10 @@ int kdb_getword(unsigned long *word, unsigned long addr, size_t size) *word = w8; break; } - /* drop through */ + fallthrough; default: diag = KDB_BADWIDTH; - kdb_printf("kdb_getword: bad width %ld\n", (long) size); + kdb_func_printf("bad width %zu\n", size); } return diag; } @@ -525,91 +496,15 @@ int kdb_putword(unsigned long addr, unsigned long word, size_t size) diag = kdb_putarea(addr, w8); break; } - /* drop through */ + fallthrough; default: diag = KDB_BADWIDTH; - kdb_printf("kdb_putword: bad width %ld\n", (long) size); + kdb_func_printf("bad width %zu\n", size); } return diag; } -/* - * kdb_task_state_string - Convert a string containing any of the - * letters DRSTCZEUIMA to a mask for the process state field and - * return the value. If no argument is supplied, return the mask - * that corresponds to environment variable PS, DRSTCZEU by - * default. - * Inputs: - * s String to convert - * Returns: - * Mask for process state. - * Notes: - * The mask folds data from several sources into a single long value, so - * be careful not to overlap the bits. TASK_* bits are in the LSB, - * special cases like UNRUNNABLE are in the MSB. As of 2.6.10-rc1 there - * is no overlap between TASK_* and EXIT_* but that may not always be - * true, so EXIT_* bits are shifted left 16 bits before being stored in - * the mask. - */ -/* unrunnable is < 0 */ -#define UNRUNNABLE (1UL << (8*sizeof(unsigned long) - 1)) -#define RUNNING (1UL << (8*sizeof(unsigned long) - 2)) -#define IDLE (1UL << (8*sizeof(unsigned long) - 3)) -#define DAEMON (1UL << (8*sizeof(unsigned long) - 4)) - -unsigned long kdb_task_state_string(const char *s) -{ - long res = 0; - if (!s) { - s = kdbgetenv("PS"); - if (!s) - s = "DRSTCZEU"; /* default value for ps */ - } - while (*s) { - switch (*s) { - case 'D': - res |= TASK_UNINTERRUPTIBLE; - break; - case 'R': - res |= RUNNING; - break; - case 'S': - res |= TASK_INTERRUPTIBLE; - break; - case 'T': - res |= TASK_STOPPED; - break; - case 'C': - res |= TASK_TRACED; - break; - case 'Z': - res |= EXIT_ZOMBIE << 16; - break; - case 'E': - res |= EXIT_DEAD << 16; - break; - case 'U': - res |= UNRUNNABLE; - break; - case 'I': - res |= IDLE; - break; - case 'M': - res |= DAEMON; - break; - case 'A': - res = ~0UL; - break; - default: - kdb_printf("%s: unknown flag '%c' ignored\n", - __func__, *s); - break; - } - ++s; - } - return res; -} /* * kdb_task_state_char - Return the character that represents the task state. @@ -620,31 +515,26 @@ unsigned long kdb_task_state_string(const char *s) */ char kdb_task_state_char (const struct task_struct *p) { - int cpu; - char state; unsigned long tmp; + char state; + int cpu; - if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long))) + if (!p || + copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long))) return 'E'; - cpu = kdb_process_cpu(p); - state = (p->state == 0) ? 'R' : - (p->state < 0) ? 'U' : - (p->state & TASK_UNINTERRUPTIBLE) ? 'D' : - (p->state & TASK_STOPPED) ? 'T' : - (p->state & TASK_TRACED) ? 'C' : - (p->exit_state & EXIT_ZOMBIE) ? 'Z' : - (p->exit_state & EXIT_DEAD) ? 'E' : - (p->state & TASK_INTERRUPTIBLE) ? 'S' : '?'; + state = task_state_to_char((struct task_struct *) p); + if (is_idle_task(p)) { /* Idle task. Is it really idle, apart from the kdb * interrupt? */ + cpu = kdb_process_cpu(p); if (!kdb_task_has_cpu(p) || kgdb_info[cpu].irq_depth == 1) { if (cpu != kdb_initial_cpu) - state = 'I'; /* idle task */ + state = '-'; /* idle task */ } - } else if (!p->mm && state == 'S') { - state = 'M'; /* sleeping system daemon */ + } else if (!p->mm && strchr("IMS", state)) { + state = tolower(state); /* sleeping system daemon */ } return state; } @@ -654,274 +544,26 @@ char kdb_task_state_char (const struct task_struct *p) * given by the mask. * Inputs: * p struct task for the process - * mask mask from kdb_task_state_string to select processes + * mask set of characters used to select processes; both NULL + * and the empty string mean adopt a default filter, which + * is to suppress sleeping system daemons and the idle tasks * Returns: * True if the process matches at least one criteria defined by the mask. */ -unsigned long kdb_task_state(const struct task_struct *p, unsigned long mask) -{ - char state[] = { kdb_task_state_char(p), '\0' }; - return (mask & kdb_task_state_string(state)) != 0; -} - -/* - * kdb_print_nameval - Print a name and its value, converting the - * value to a symbol lookup if possible. - * Inputs: - * name field name to print - * val value of field - */ -void kdb_print_nameval(const char *name, unsigned long val) +bool kdb_task_state(const struct task_struct *p, const char *mask) { - kdb_symtab_t symtab; - kdb_printf(" %-11.11s ", name); - if (kdbnearsym(val, &symtab)) - kdb_symbol_print(val, &symtab, - KDB_SP_VALUE|KDB_SP_SYMSIZE|KDB_SP_NEWLINE); - else - kdb_printf("0x%lx\n", val); -} - -/* Last ditch allocator for debugging, so we can still debug even when - * the GFP_ATOMIC pool has been exhausted. The algorithms are tuned - * for space usage, not for speed. One smallish memory pool, the free - * chain is always in ascending address order to allow coalescing, - * allocations are done in brute force best fit. - */ + char state = kdb_task_state_char(p); -struct debug_alloc_header { - u32 next; /* offset of next header from start of pool */ - u32 size; - void *caller; -}; - -/* The memory returned by this allocator must be aligned, which means - * so must the header size. Do not assume that sizeof(struct - * debug_alloc_header) is a multiple of the alignment, explicitly - * calculate the overhead of this header, including the alignment. - * The rest of this code must not use sizeof() on any header or - * pointer to a header. - */ -#define dah_align 8 -#define dah_overhead ALIGN(sizeof(struct debug_alloc_header), dah_align) - -static u64 debug_alloc_pool_aligned[256*1024/dah_align]; /* 256K pool */ -static char *debug_alloc_pool = (char *)debug_alloc_pool_aligned; -static u32 dah_first, dah_first_call = 1, dah_used, dah_used_max; - -/* Locking is awkward. The debug code is called from all contexts, - * including non maskable interrupts. A normal spinlock is not safe - * in NMI context. Try to get the debug allocator lock, if it cannot - * be obtained after a second then give up. If the lock could not be - * previously obtained on this cpu then only try once. - * - * sparse has no annotation for "this function _sometimes_ acquires a - * lock", so fudge the acquire/release notation. - */ -static DEFINE_SPINLOCK(dap_lock); -static int get_dap_lock(void) - __acquires(dap_lock) -{ - static int dap_locked = -1; - int count; - if (dap_locked == smp_processor_id()) - count = 1; - else - count = 1000; - while (1) { - if (spin_trylock(&dap_lock)) { - dap_locked = -1; - return 1; - } - if (!count--) - break; - udelay(1000); - } - dap_locked = smp_processor_id(); - __acquire(dap_lock); - return 0; -} - -void *debug_kmalloc(size_t size, gfp_t flags) -{ - unsigned int rem, h_offset; - struct debug_alloc_header *best, *bestprev, *prev, *h; - void *p = NULL; - if (!get_dap_lock()) { - __release(dap_lock); /* we never actually got it */ - return NULL; - } - h = (struct debug_alloc_header *)(debug_alloc_pool + dah_first); - if (dah_first_call) { - h->size = sizeof(debug_alloc_pool_aligned) - dah_overhead; - dah_first_call = 0; - } - size = ALIGN(size, dah_align); - prev = best = bestprev = NULL; - while (1) { - if (h->size >= size && (!best || h->size < best->size)) { - best = h; - bestprev = prev; - if (h->size == size) - break; - } - if (!h->next) - break; - prev = h; - h = (struct debug_alloc_header *)(debug_alloc_pool + h->next); - } - if (!best) - goto out; - rem = best->size - size; - /* The pool must always contain at least one header */ - if (best->next == 0 && bestprev == NULL && rem < dah_overhead) - goto out; - if (rem >= dah_overhead) { - best->size = size; - h_offset = ((char *)best - debug_alloc_pool) + - dah_overhead + best->size; - h = (struct debug_alloc_header *)(debug_alloc_pool + h_offset); - h->size = rem - dah_overhead; - h->next = best->next; - } else - h_offset = best->next; - best->caller = __builtin_return_address(0); - dah_used += best->size; - dah_used_max = max(dah_used, dah_used_max); - if (bestprev) - bestprev->next = h_offset; - else - dah_first = h_offset; - p = (char *)best + dah_overhead; - memset(p, POISON_INUSE, best->size - 1); - *((char *)p + best->size - 1) = POISON_END; -out: - spin_unlock(&dap_lock); - return p; -} - -void debug_kfree(void *p) -{ - struct debug_alloc_header *h; - unsigned int h_offset; - if (!p) - return; - if ((char *)p < debug_alloc_pool || - (char *)p >= debug_alloc_pool + sizeof(debug_alloc_pool_aligned)) { - kfree(p); - return; - } - if (!get_dap_lock()) { - __release(dap_lock); /* we never actually got it */ - return; /* memory leak, cannot be helped */ - } - h = (struct debug_alloc_header *)((char *)p - dah_overhead); - memset(p, POISON_FREE, h->size - 1); - *((char *)p + h->size - 1) = POISON_END; - h->caller = NULL; - dah_used -= h->size; - h_offset = (char *)h - debug_alloc_pool; - if (h_offset < dah_first) { - h->next = dah_first; - dah_first = h_offset; - } else { - struct debug_alloc_header *prev; - unsigned int prev_offset; - prev = (struct debug_alloc_header *)(debug_alloc_pool + - dah_first); - while (1) { - if (!prev->next || prev->next > h_offset) - break; - prev = (struct debug_alloc_header *) - (debug_alloc_pool + prev->next); - } - prev_offset = (char *)prev - debug_alloc_pool; - if (prev_offset + dah_overhead + prev->size == h_offset) { - prev->size += dah_overhead + h->size; - memset(h, POISON_FREE, dah_overhead - 1); - *((char *)h + dah_overhead - 1) = POISON_END; - h = prev; - h_offset = prev_offset; - } else { - h->next = prev->next; - prev->next = h_offset; - } - } - if (h_offset + dah_overhead + h->size == h->next) { - struct debug_alloc_header *next; - next = (struct debug_alloc_header *) - (debug_alloc_pool + h->next); - h->size += dah_overhead + next->size; - h->next = next->next; - memset(next, POISON_FREE, dah_overhead - 1); - *((char *)next + dah_overhead - 1) = POISON_END; - } - spin_unlock(&dap_lock); -} - -void debug_kusage(void) -{ - struct debug_alloc_header *h_free, *h_used; -#ifdef CONFIG_IA64 - /* FIXME: using dah for ia64 unwind always results in a memory leak. - * Fix that memory leak first, then set debug_kusage_one_time = 1 for - * all architectures. + /* If there is no mask, then we will filter code that runs when the + * scheduler is idling and any system daemons that are currently + * sleeping. */ - static int debug_kusage_one_time; -#else - static int debug_kusage_one_time = 1; -#endif - if (!get_dap_lock()) { - __release(dap_lock); /* we never actually got it */ - return; - } - h_free = (struct debug_alloc_header *)(debug_alloc_pool + dah_first); - if (dah_first == 0 && - (h_free->size == sizeof(debug_alloc_pool_aligned) - dah_overhead || - dah_first_call)) - goto out; - if (!debug_kusage_one_time) - goto out; - debug_kusage_one_time = 0; - kdb_printf("%s: debug_kmalloc memory leak dah_first %d\n", - __func__, dah_first); - if (dah_first) { - h_used = (struct debug_alloc_header *)debug_alloc_pool; - kdb_printf("%s: h_used %p size %d\n", __func__, h_used, - h_used->size); - } - do { - h_used = (struct debug_alloc_header *) - ((char *)h_free + dah_overhead + h_free->size); - kdb_printf("%s: h_used %p size %d caller %p\n", - __func__, h_used, h_used->size, h_used->caller); - h_free = (struct debug_alloc_header *) - (debug_alloc_pool + h_free->next); - } while (h_free->next); - h_used = (struct debug_alloc_header *) - ((char *)h_free + dah_overhead + h_free->size); - if ((char *)h_used - debug_alloc_pool != - sizeof(debug_alloc_pool_aligned)) - kdb_printf("%s: h_used %p size %d caller %p\n", - __func__, h_used, h_used->size, h_used->caller); -out: - spin_unlock(&dap_lock); -} - -/* Maintain a small stack of kdb_flags to allow recursion without disturbing - * the global kdb state. - */ + if (!mask || mask[0] == '\0') + return !strchr("-ims", state); -static int kdb_flags_stack[4], kdb_flags_index; + /* A is a special case that matches all states */ + if (strchr(mask, 'A')) + return true; -void kdb_save_flags(void) -{ - BUG_ON(kdb_flags_index >= ARRAY_SIZE(kdb_flags_stack)); - kdb_flags_stack[kdb_flags_index++] = kdb_flags; -} - -void kdb_restore_flags(void) -{ - BUG_ON(kdb_flags_index <= 0); - kdb_flags = kdb_flags_stack[--kdb_flags_index]; + return strchr(mask, state); } |