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Date:   Fri, 9 Sep 2022 22:07:46 +0900
From:   Masami Hiramatsu (Google) <mhiramat@kernel.org>
To:     Li Qiang <liq3ea@163.com>
Cc:     naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com,
        davem@davemloft.net, linux-kernel@vger.kernel.org,
        liq3ea@gmail.com, Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH] kprobe: reverse kp->flags when arm_kprobe failed
Message-Id: <20220909220746.a7826cb2fb9da02171b38237@kernel.org>
In-Reply-To: <20220902155820.34755-1-liq3ea@163.com>
References: <20220902155820.34755-1-liq3ea@163.com>
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On Fri,  2 Sep 2022 08:58:20 -0700
Li Qiang <liq3ea@163.com> wrote:

> In aggregate kprobe case, when arm_kprobe failed,
> we need set the kp->flags with KPROBE_FLAG_DISABLED again.
> If not, the 'kp' kprobe will been considered as enabled
> but it actually not enabled.
> 
> Signed-off-by: Li Qiang <liq3ea@163.com>

Looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thanks!

> ---
>  kernel/kprobes.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 08350e35a..333454df5 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -2424,8 +2424,11 @@ 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);
> -- 
> 2.25.1
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>