diff options
Diffstat (limited to 'arch/csky/kernel/probes/kprobes.c')
| -rw-r--r-- | arch/csky/kernel/probes/kprobes.c | 115 |
1 files changed, 14 insertions, 101 deletions
diff --git a/arch/csky/kernel/probes/kprobes.c b/arch/csky/kernel/probes/kprobes.c index f0f733b7ac5a..3c6e5c725d81 100644 --- a/arch/csky/kernel/probes/kprobes.c +++ b/arch/csky/kernel/probes/kprobes.c @@ -1,5 +1,7 @@ // SPDX-License-Identifier: GPL-2.0+ +#define pr_fmt(fmt) "kprobes: " fmt + #include <linux/kprobes.h> #include <linux/extable.h> #include <linux/slab.h> @@ -28,7 +30,7 @@ static int __kprobes patch_text_cb(void *priv) struct csky_insn_patch *param = priv; unsigned int addr = (unsigned int)param->addr; - if (atomic_inc_return(¶m->cpu_count) == 1) { + if (atomic_inc_return(¶m->cpu_count) == num_online_cpus()) { *(u16 *) addr = cpu_to_le16(param->opcode); dcache_wb_range(addr, addr + 2); atomic_inc(¶m->cpu_count); @@ -77,10 +79,8 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) { unsigned long probe_addr = (unsigned long)p->addr; - if (probe_addr & 0x1) { - pr_warn("Address not aligned.\n"); - return -EINVAL; - } + if (probe_addr & 0x1) + return -EILSEQ; /* copy instruction */ p->opcode = le32_to_cpu(*p->addr); @@ -124,6 +124,10 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p) void __kprobes arch_remove_kprobe(struct kprobe *p) { + if (p->ainsn.api.insn) { + free_insn_slot(p->ainsn.api.insn, 0); + p->ainsn.api.insn = NULL; + } } static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb) @@ -225,7 +229,7 @@ static int __kprobes reenter_kprobe(struct kprobe *p, break; case KPROBE_HIT_SS: case KPROBE_REENTER: - pr_warn("Unrecoverable kprobe detected.\n"); + pr_warn("Failed to recover from reentered kprobes.\n"); dump_kprobe(p); BUG(); break; @@ -283,8 +287,7 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned int trapnr) * normal page fault. */ regs->pc = (unsigned long) cur->addr; - if (!instruction_pointer(regs)) - BUG(); + BUG_ON(!instruction_pointer(regs)); if (kcb->kprobe_status == KPROBE_REENTER) restore_previous_kprobe(kcb); @@ -295,23 +298,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned int trapnr) case KPROBE_HIT_ACTIVE: case KPROBE_HIT_SSDONE: /* - * We increment the nmissed count for accounting, - * we can also use npre/npostfault count for accounting - * these specific fault cases. - */ - kprobes_inc_nmissed_count(cur); - - /* - * We come here because instructions in the pre/post - * handler caused the page_fault, this could happen - * if handler tries to access user space by - * copy_from_user(), get_user() etc. Let the - * user-specified handler try to fix it first. - */ - if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr)) - return 1; - - /* * In case the user-specified fault handler returned * zero, try to fix up. */ @@ -404,88 +390,15 @@ int __init arch_populate_kprobe_blacklist(void) void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) { - struct kretprobe_instance *ri = NULL; - struct hlist_head *head, empty_rp; - struct hlist_node *tmp; - unsigned long flags, orig_ret_address = 0; - unsigned long trampoline_address = - (unsigned long)&kretprobe_trampoline; - kprobe_opcode_t *correct_ret_addr = NULL; - - INIT_HLIST_HEAD(&empty_rp); - kretprobe_hash_lock(current, &head, &flags); - - /* - * It is possible to have multiple instances associated with a given - * task either because multiple functions in the call path have - * return probes installed on them, and/or more than one - * return probe was registered for a target function. - * - * We can handle this because: - * - instances are always pushed into the head of the list - * - when multiple return probes are registered for the same - * function, the (chronologically) first instance's ret_addr - * will be the real return address, and all the rest will - * point to kretprobe_trampoline. - */ - hlist_for_each_entry_safe(ri, tmp, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - - orig_ret_address = (unsigned long)ri->ret_addr; - - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - - kretprobe_assert(ri, orig_ret_address, trampoline_address); - - correct_ret_addr = ri->ret_addr; - hlist_for_each_entry_safe(ri, tmp, head, hlist) { - if (ri->task != current) - /* another task is sharing our hash bucket */ - continue; - - orig_ret_address = (unsigned long)ri->ret_addr; - if (ri->rp && ri->rp->handler) { - __this_cpu_write(current_kprobe, &ri->rp->kp); - get_kprobe_ctlblk()->kprobe_status = KPROBE_HIT_ACTIVE; - ri->ret_addr = correct_ret_addr; - ri->rp->handler(ri, regs); - __this_cpu_write(current_kprobe, NULL); - } - - recycle_rp_inst(ri, &empty_rp); - - if (orig_ret_address != trampoline_address) - /* - * This is the real return address. Any other - * instances associated with this task are for - * other calls deeper on the call stack - */ - break; - } - - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } - return (void *)orig_ret_address; + return (void *)kretprobe_trampoline_handler(regs, NULL); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *)regs->lr; - regs->lr = (unsigned long) &kretprobe_trampoline; + ri->fp = NULL; + regs->lr = (unsigned long) &__kretprobe_trampoline; } int __kprobes arch_trampoline_kprobe(struct kprobe *p) |