diff options
| author | Masami Hiramatsu <mhiramat@kernel.org> | 2020-08-29 22:01:19 +0900 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-09-08 11:52:33 +0200 |
| commit | 2ef12450856121f092621d4305885ec20283260e (patch) | |
| tree | 6006235580e408496ab297d5810cd8d9bf762706 /arch/mips/kernel/kprobes.c | |
| parent | e792ff804f49720ce003b3e4c618b5d996256a18 (diff) | |
mips: 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/159870607968.1229682.12100697467108845587.stgit@devnote2
Diffstat (limited to 'arch/mips/kernel/kprobes.c')
| -rw-r--r-- | arch/mips/kernel/kprobes.c | 54 |
1 files changed, 3 insertions, 51 deletions
diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c index d043c2f897fc..54dfba8fa77c 100644 --- a/arch/mips/kernel/kprobes.c +++ b/arch/mips/kernel/kprobes.c @@ -477,6 +477,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *) regs->regs[31]; + ri->fp = NULL; /* Replace the return addr with trampoline addr */ regs->regs[31] = (unsigned long)kretprobe_trampoline; @@ -488,57 +489,8 @@ 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); - instruction_pointer(regs) = orig_ret_address; - - kretprobe_hash_unlock(current, &flags); - - hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { - hlist_del(&ri->hlist); - kfree(ri); - } + instruction_pointer(regs) = __kretprobe_trampoline_handler(regs, + kretprobe_trampoline, NULL); /* * By returning a non-zero value, we are telling * kprobe_handler() that we don't want the post_handler |