From: Yang Jihong <yangjihong1@xxxxxxxxxx>
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@xxxxxxxxxx/
Fixes: f66c0447cca1 ("kprobes: Set unoptimized flag after unoptimizing code")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Yang Jihong <yangjihong1@xxxxxxxxxx>
Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/kprobes/opt.c | 4 ++--
include/linux/kprobes.h | 1 +
kernel/kprobes.c | 2 +-
3 files changed, 4 insertions(+), 3 deletions(-)
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -46,8 +46,8 @@ unsigned long __recover_optprobed_insn(k
/* This function only handles jump-optimized kprobe */
if (kp && kprobe_optimized(kp)) {
op = container_of(kp, struct optimized_kprobe, kp);
- /* If op->list is not empty, op is under optimizing */
- if (list_empty(&op->list))
+ /* If op is optimized or under unoptimizing */
+ if (list_empty(&op->list) || optprobe_queued_unopt(op))
goto found;
}
}
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -342,6 +342,7 @@ extern int proc_kprobes_optimization_han
size_t *length, loff_t *ppos);
#endif
extern void wait_for_kprobe_optimizer(void);
+bool optprobe_queued_unopt(struct optimized_kprobe *op);
#else
static inline void wait_for_kprobe_optimizer(void) { }
#endif /* CONFIG_OPTPROBES */
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -652,7 +652,7 @@ void wait_for_kprobe_optimizer(void)
mutex_unlock(&kprobe_mutex);
}
-static bool optprobe_queued_unopt(struct optimized_kprobe *op)
+bool optprobe_queued_unopt(struct optimized_kprobe *op)
{
struct optimized_kprobe *_op;
