From: Yang Jihong Date: Mon, 20 Feb 2023 23:49:16 +0000 (+0900) Subject: x86/kprobes: Fix __recover_optprobed_insn check optimizing logic X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c5a2c2bf0b4f0b1e0d20e0d1ea73563f09dbf458;p=linux.git 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 Acked-by: Masami Hiramatsu (Google) Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index a9121073d9518..331ff4246a969 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -46,8 +46,8 @@ unsigned long __recover_optprobed_insn(kprobe_opcode_t *buf, unsigned long addr) /* 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; } } diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index ef8c7accbc689..bf79646cc2d0c 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -349,6 +349,7 @@ extern int proc_kprobes_optimization_handler(struct ctl_table *table, 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 */ diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 8818f3a89fef3..e3885f9f86d0e 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -656,7 +656,7 @@ 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;