diff options
| author | Masami Hiramatsu <mhiramat@kernel.org> | 2020-08-29 22:00:46 +0900 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-09-08 11:52:32 +0200 |
| commit | f75dd136b65cccfaf3869be5380f401538fa9f72 (patch) | |
| tree | 449eee6d36270bf7e594ca0b9345444b7b87c9f3 /arch | |
| parent | 95a4b7a24f55efd4fbc77c020fe0aab3e1f37f8a (diff) | |
| download | linux-f75dd136b65cccfaf3869be5380f401538fa9f72.tar.bz2 | |
arc: kprobes: Use generic kretprobe trampoline handler
Use the generic kretprobe trampoline handler. Don't use
framepointer verification.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/159870604671.1229682.13639386820521358456.stgit@devnote2
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arc/kernel/kprobes.c | 54 |
1 files changed, 2 insertions, 52 deletions
diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c index 7d3efe83cba7..cabef45f11df 100644 --- a/arch/arc/kernel/kprobes.c +++ b/arch/arc/kernel/kprobes.c @@ -388,6 +388,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, { ri->ret_addr = (kprobe_opcode_t *) regs->blink; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->blink = (unsigned long)&kretprobe_trampoline; @@ -396,58 +397,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, static int __kprobes trampoline_probe_handler(struct kprobe *p, 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; - - 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 an multiple functions in the call path - * have a return probe installed on them, and/or more than one return - * return probe was registered for a target function. - * - * We can handle this because: - * - instances are always inserted at the head of the list - * - when multiple return probes are registered for the same - * function, the first instance's ret_addr will point to 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; - - if (ri->rp && ri->rp->handler) - ri->rp->handler(ri, regs); - - orig_ret_address = (unsigned long)ri->ret_addr; - 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_assert(ri, orig_ret_address, trampoline_address); - regs->ret = orig_ret_address; - - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } + regs->ret = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); /* By returning a non zero value, we are telling the kprobe handler * that we don't want the post_handler to run |