x86/kprobes: Fix __recover_optprobed_insn check optimizing logic
authorYang Jihong <yangjihong1@huawei.com>
Mon, 20 Feb 2023 23:49:16 +0000 (08:49 +0900)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 10 Mar 2023 08:40:01 +0000 (09:40 +0100)
commitc5a2c2bf0b4f0b1e0d20e0d1ea73563f09dbf458
treecc9e160a83091150f575c3b7043300556bfc041d
parentf46a42130c03d2359b544eab957cf38fe9d42e69
x86/kprobes: Fix __recover_optprobed_insn check optimizing logic

commit 868a6fc0ca2407622d2833adefe1c4d284766c4c upstream.

Since the following commit:

  commit f66c0447cca1 ("kprobes: Set unoptimized flag after unoptimizing code")

modified the update timing of the KPROBE_FLAG_OPTIMIZED, a optimized_kprobe
may be in the optimizing or unoptimizing state when op.kp->flags
has KPROBE_FLAG_OPTIMIZED and op->list is not empty.

The __recover_optprobed_insn check logic is incorrect, a kprobe in the
unoptimizing state may be incorrectly determined as unoptimizing.
As a result, incorrect instructions are copied.

The optprobe_queued_unopt function needs to be exported for invoking in
arch directory.

Link: https://lore.kernel.org/all/20230216034247.32348-2-yangjihong1@huawei.com/
Fixes: f66c0447cca1 ("kprobes: Set unoptimized flag after unoptimizing code")
Cc: stable@vger.kernel.org
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/kprobes/opt.c
include/linux/kprobes.h
kernel/kprobes.c