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-Tag: v4.14.308~79 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=31f7904bef2b1ba162ee50e730da5f44095e5ac2;p=thirdparty%2Fkernel%2Fstable.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 f4e4db0cbd598..ce1b87d8a7c05 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -56,8 +56,8 @@ 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 019444c04f58b..7ea04300167b1 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -353,6 +353,7 @@ 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 52058ff3ccbfe..3cef04e5ecbf0 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -626,7 +626,7 @@ 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;