From: Chuang Wang nashuiliang@gmail.com
In aggrprobe scenes, if arm_kprobe() returns an error(e.g. livepatch and kprobe are using the same function X), kprobe flags, while has been modified to ~KPROBE_FLAG_DISABLED, is not rollled back.
Then, __disable_kprobe() will be failed in __unregister_kprobe_top(), the kprobe list will be not removed from aggrprobe, memory leaks or illegal pointers will be caused.
WARN disarm_kprobe: Failed to disarm kprobe-ftrace at 00000000c729fdbc (-2) RIP: 0010:disarm_kprobe+0xcc/0x110 Call Trace: __disable_kprobe+0x78/0x90 __unregister_kprobe_top+0x13/0x1b0 ? _cond_resched+0x15/0x30 unregister_kprobes+0x32/0x80 unregister_kprobe+0x1a/0x20
Illegal Pointers: BUG: unable to handle kernel paging request at 0000000000656369 RIP: 0010:__get_valid_kprobe+0x69/0x90 Call Trace: register_kprobe+0x30/0x60 __register_trace_kprobe.part.7+0x8b/0xc0 create_local_trace_kprobe+0xd2/0x130 perf_kprobe_init+0x83/0xd0
Fixes: 12310e343755 ("kprobes: Propagate error from arm_kprobe_ftrace()") Cc: stable@vger.kernel.org Signed-off-by: Jingren Zhou zhoujingren@didiglobal.com Signed-off-by: Chuang Wang nashuiliang@gmail.com
--- v1->v2: - Supplement commit information: fixline, Cc stable
kernel/kprobes.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index f214f8c088ed..c11c79e05a4c 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2422,8 +2422,11 @@ int enable_kprobe(struct kprobe *kp) if (!kprobes_all_disarmed && kprobe_disabled(p)) { p->flags &= ~KPROBE_FLAG_DISABLED; ret = arm_kprobe(p); - if (ret) + if (ret) { p->flags |= KPROBE_FLAG_DISABLED; + if (p != kp) + kp->flags |= KPROBE_FLAG_DISABLED; + } } out: mutex_unlock(&kprobe_mutex);