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-rw-r--r--arch/arm64/kernel/cpufeature.c22
-rw-r--r--arch/arm64/kernel/debug-monitors.c14
-rw-r--r--arch/arm64/kernel/ftrace.c22
-rw-r--r--arch/arm64/kernel/hw_breakpoint.c11
-rw-r--r--arch/arm64/kernel/module.c4
-rw-r--r--arch/arm64/kernel/probes/kprobes.c40
-rw-r--r--arch/arm64/kernel/return_address.c3
-rw-r--r--arch/arm64/kernel/smp.c2
-rw-r--r--arch/arm64/kernel/stacktrace.c3
-rw-r--r--arch/arm64/kernel/traps.c1
10 files changed, 64 insertions, 58 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index f29f36a65175..b1fdc486aed8 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -184,9 +184,17 @@ static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
};
static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
- S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
- S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
- ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
+ /*
+ * We already refuse to boot CPUs that don't support our configured
+ * page size, so we can only detect mismatches for a page size other
+ * than the one we're currently using. Unfortunately, SoCs like this
+ * exist in the wild so, even though we don't like it, we'll have to go
+ * along with it and treat them as non-strict.
+ */
+ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN4_SHIFT, 4, ID_AA64MMFR0_TGRAN4_NI),
+ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN64_SHIFT, 4, ID_AA64MMFR0_TGRAN64_NI),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_TGRAN16_SHIFT, 4, ID_AA64MMFR0_TGRAN16_NI),
+
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_BIGENDEL0_SHIFT, 4, 0),
/* Linux shouldn't care about secure memory */
ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_SNSMEM_SHIFT, 4, 0),
@@ -225,8 +233,8 @@ static const struct arm64_ftr_bits ftr_ctr[] = {
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, 31, 1, 1), /* RES1 */
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DIC_SHIFT, 1, 1),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_IDC_SHIFT, 1, 1),
- ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, CTR_CWG_SHIFT, 4, 0),
- ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_SAFE, CTR_ERG_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_CWG_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_HIGHER_OR_ZERO_SAFE, CTR_ERG_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, CTR_DMINLINE_SHIFT, 4, 1),
/*
* Linux can handle differing I-cache policies. Userspace JITs will
@@ -468,6 +476,10 @@ static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
case FTR_LOWER_SAFE:
ret = new < cur ? new : cur;
break;
+ case FTR_HIGHER_OR_ZERO_SAFE:
+ if (!cur || !new)
+ break;
+ /* Fallthrough */
case FTR_HIGHER_SAFE:
ret = new > cur ? new : cur;
break;
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index f8719bd30850..48222a4760c2 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -207,16 +207,16 @@ static int call_step_hook(struct pt_regs *regs, unsigned int esr)
list = user_mode(regs) ? &user_step_hook : &kernel_step_hook;
- rcu_read_lock();
-
+ /*
+ * Since single-step exception disables interrupt, this function is
+ * entirely not preemptible, and we can use rcu list safely here.
+ */
list_for_each_entry_rcu(hook, list, node) {
retval = hook->fn(regs, esr);
if (retval == DBG_HOOK_HANDLED)
break;
}
- rcu_read_unlock();
-
return retval;
}
NOKPROBE_SYMBOL(call_step_hook);
@@ -305,14 +305,16 @@ static int call_break_hook(struct pt_regs *regs, unsigned int esr)
list = user_mode(regs) ? &user_break_hook : &kernel_break_hook;
- rcu_read_lock();
+ /*
+ * Since brk exception disables interrupt, this function is
+ * entirely not preemptible, and we can use rcu list safely here.
+ */
list_for_each_entry_rcu(hook, list, node) {
unsigned int comment = esr & ESR_ELx_BRK64_ISS_COMMENT_MASK;
if ((comment & ~hook->mask) == hook->imm)
fn = hook->fn;
}
- rcu_read_unlock();
return fn ? fn(regs, esr) : DBG_HOOK_ERROR;
}
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index 1285c7b2947f..171773257974 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -73,7 +73,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
if (offset < -SZ_128M || offset >= SZ_128M) {
#ifdef CONFIG_ARM64_MODULE_PLTS
- struct plt_entry trampoline;
+ struct plt_entry trampoline, *dst;
struct module *mod;
/*
@@ -106,23 +106,27 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
* to check if the actual opcodes are in fact identical,
* regardless of the offset in memory so use memcmp() instead.
*/
- trampoline = get_plt_entry(addr, mod->arch.ftrace_trampoline);
- if (memcmp(mod->arch.ftrace_trampoline, &trampoline,
- sizeof(trampoline))) {
- if (plt_entry_is_initialized(mod->arch.ftrace_trampoline)) {
+ dst = mod->arch.ftrace_trampoline;
+ trampoline = get_plt_entry(addr, dst);
+ if (memcmp(dst, &trampoline, sizeof(trampoline))) {
+ if (plt_entry_is_initialized(dst)) {
pr_err("ftrace: far branches to multiple entry points unsupported inside a single module\n");
return -EINVAL;
}
/* point the trampoline to our ftrace entry point */
module_disable_ro(mod);
- *mod->arch.ftrace_trampoline = trampoline;
+ *dst = trampoline;
module_enable_ro(mod, true);
- /* update trampoline before patching in the branch */
- smp_wmb();
+ /*
+ * Ensure updated trampoline is visible to instruction
+ * fetch before we patch in the branch.
+ */
+ __flush_icache_range((unsigned long)&dst[0],
+ (unsigned long)&dst[1]);
}
- addr = (unsigned long)(void *)mod->arch.ftrace_trampoline;
+ addr = (unsigned long)dst;
#else /* CONFIG_ARM64_MODULE_PLTS */
return -EINVAL;
#endif /* CONFIG_ARM64_MODULE_PLTS */
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index dceb84520948..38ee1514cd9c 100644
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -536,13 +536,18 @@ int hw_breakpoint_arch_parse(struct perf_event *bp,
/* Aligned */
break;
case 1:
- /* Allow single byte watchpoint. */
- if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1)
- break;
case 2:
/* Allow halfword watchpoints and breakpoints. */
if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2)
break;
+
+ /* Fallthrough */
+ case 3:
+ /* Allow single byte watchpoint. */
+ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1)
+ break;
+
+ /* Fallthrough */
default:
return -EINVAL;
}
diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index 46e643e30708..03ff15bffbb6 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -314,18 +314,21 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
/* MOVW instruction relocations. */
case R_AARCH64_MOVW_UABS_G0_NC:
overflow_check = false;
+ /* Fall through */
case R_AARCH64_MOVW_UABS_G0:
ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 0,
AARCH64_INSN_IMM_MOVKZ);
break;
case R_AARCH64_MOVW_UABS_G1_NC:
overflow_check = false;
+ /* Fall through */
case R_AARCH64_MOVW_UABS_G1:
ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 16,
AARCH64_INSN_IMM_MOVKZ);
break;
case R_AARCH64_MOVW_UABS_G2_NC:
overflow_check = false;
+ /* Fall through */
case R_AARCH64_MOVW_UABS_G2:
ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 32,
AARCH64_INSN_IMM_MOVKZ);
@@ -393,6 +396,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
break;
case R_AARCH64_ADR_PREL_PG_HI21_NC:
overflow_check = false;
+ /* Fall through */
case R_AARCH64_ADR_PREL_PG_HI21:
ovf = reloc_insn_adrp(me, sechdrs, loc, val);
if (ovf && ovf != -ERANGE)
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index bd5dfffca272..c4452827419b 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -21,6 +21,7 @@
#include <asm/ptrace.h>
#include <asm/cacheflush.h>
#include <asm/debug-monitors.h>
+#include <asm/daifflags.h>
#include <asm/system_misc.h>
#include <asm/insn.h>
#include <linux/uaccess.h>
@@ -168,33 +169,6 @@ static void __kprobes set_current_kprobe(struct kprobe *p)
}
/*
- * When PSTATE.D is set (masked), then software step exceptions can not be
- * generated.
- * SPSR's D bit shows the value of PSTATE.D immediately before the
- * exception was taken. PSTATE.D is set while entering into any exception
- * mode, however software clears it for any normal (none-debug-exception)
- * mode in the exception entry. Therefore, when we are entering into kprobe
- * breakpoint handler from any normal mode then SPSR.D bit is already
- * cleared, however it is set when we are entering from any debug exception
- * mode.
- * Since we always need to generate single step exception after a kprobe
- * breakpoint exception therefore we need to clear it unconditionally, when
- * we become sure that the current breakpoint exception is for kprobe.
- */
-static void __kprobes
-spsr_set_debug_flag(struct pt_regs *regs, int mask)
-{
- unsigned long spsr = regs->pstate;
-
- if (mask)
- spsr |= PSR_D_BIT;
- else
- spsr &= ~PSR_D_BIT;
-
- regs->pstate = spsr;
-}
-
-/*
* Interrupts need to be disabled before single-step mode is set, and not
* reenabled until after single-step mode ends.
* Without disabling interrupt on local CPU, there is a chance of
@@ -205,17 +179,17 @@ spsr_set_debug_flag(struct pt_regs *regs, int mask)
static void __kprobes kprobes_save_local_irqflag(struct kprobe_ctlblk *kcb,
struct pt_regs *regs)
{
- kcb->saved_irqflag = regs->pstate;
+ kcb->saved_irqflag = regs->pstate & DAIF_MASK;
regs->pstate |= PSR_I_BIT;
+ /* Unmask PSTATE.D for enabling software step exceptions. */
+ regs->pstate &= ~PSR_D_BIT;
}
static void __kprobes kprobes_restore_local_irqflag(struct kprobe_ctlblk *kcb,
struct pt_regs *regs)
{
- if (kcb->saved_irqflag & PSR_I_BIT)
- regs->pstate |= PSR_I_BIT;
- else
- regs->pstate &= ~PSR_I_BIT;
+ regs->pstate &= ~DAIF_MASK;
+ regs->pstate |= kcb->saved_irqflag;
}
static void __kprobes
@@ -252,8 +226,6 @@ static void __kprobes setup_singlestep(struct kprobe *p,
set_ss_context(kcb, slot); /* mark pending ss */
- spsr_set_debug_flag(regs, 0);
-
/* IRQs and single stepping do not mix well. */
kprobes_save_local_irqflag(kcb, regs);
kernel_enable_single_step(regs);
diff --git a/arch/arm64/kernel/return_address.c b/arch/arm64/kernel/return_address.c
index c4ae647d2306..a5e8b3b9d798 100644
--- a/arch/arm64/kernel/return_address.c
+++ b/arch/arm64/kernel/return_address.c
@@ -8,6 +8,7 @@
#include <linux/export.h>
#include <linux/ftrace.h>
+#include <linux/kprobes.h>
#include <asm/stack_pointer.h>
#include <asm/stacktrace.h>
@@ -29,6 +30,7 @@ static int save_return_addr(struct stackframe *frame, void *d)
return 0;
}
}
+NOKPROBE_SYMBOL(save_return_addr);
void *return_address(unsigned int level)
{
@@ -49,3 +51,4 @@ void *return_address(unsigned int level)
return NULL;
}
EXPORT_SYMBOL_GPL(return_address);
+NOKPROBE_SYMBOL(return_address);
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index ea90d3bd9253..018a33e01b0e 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -152,8 +152,8 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
pr_crit("CPU%u: died during early boot\n", cpu);
break;
}
- /* Fall through */
pr_crit("CPU%u: may not have shut down cleanly\n", cpu);
+ /* Fall through */
case CPU_STUCK_IN_KERNEL:
pr_crit("CPU%u: is stuck in kernel\n", cpu);
if (status & CPU_STUCK_REASON_52_BIT_VA)
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index 2b160ae594eb..a336cb124320 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -7,6 +7,7 @@
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/ftrace.h>
+#include <linux/kprobes.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
@@ -111,6 +112,7 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame)
return 0;
}
+NOKPROBE_SYMBOL(unwind_frame);
void notrace walk_stackframe(struct task_struct *tsk, struct stackframe *frame,
int (*fn)(struct stackframe *, void *), void *data)
@@ -125,6 +127,7 @@ void notrace walk_stackframe(struct task_struct *tsk, struct stackframe *frame,
break;
}
}
+NOKPROBE_SYMBOL(walk_stackframe);
#ifdef CONFIG_STACKTRACE
struct stack_trace_data {
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index d3313797cca9..32893b3d9164 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -733,6 +733,7 @@ static const char *esr_class_str[] = {
[ESR_ELx_EC_CP14_LS] = "CP14 LDC/STC",
[ESR_ELx_EC_FP_ASIMD] = "ASIMD",
[ESR_ELx_EC_CP10_ID] = "CP10 MRC/VMRS",
+ [ESR_ELx_EC_PAC] = "PAC",
[ESR_ELx_EC_CP14_64] = "CP14 MCRR/MRRC",
[ESR_ELx_EC_ILL] = "PSTATE.IL",
[ESR_ELx_EC_SVC32] = "SVC (AArch32)",
generated by cgit (git 2.34.1) at 2024-06-08 18:50:15 +0000