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Message-ID: <470ea2ee-54fd-3dd5-2500-36fb82665c11@huawei.com>
Date:   Fri, 30 Sep 2022 09:42:52 +0800
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Subject: Re: [bug report] misc/fsck.c: Processes may kill other processes.
To:     Lukas Czerner <lczerner@redhat.com>
CC:     Theodore Ts'o <tytso@mit.edu>, <linux-ext4@vger.kernel.org>,
        <liuzhiqiang26@huawei.com>, linfeilong <linfeilong@huawei.com>
References: <4ffe3143-fc53-7178-cf44-f3481eb96ae4@huawei.com>
 <20220929112813.6aqtktwaff2m7fh2@fedora>
From:   zhanchengbin <zhanchengbin1@huawei.com>
In-Reply-To: <20220929112813.6aqtktwaff2m7fh2@fedora>
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On 2022/9/29 19:28, Lukas Czerner wrote:
> Hi,
> 
> indeed we'd like to avoid killing the instance that was not ran because
> of noexecute. Can you try the following patch?
> 
> Thanks!
> -Lukas

Yes, you're right, I think we can fix it in this way.

diff --git a/misc/fsck.c b/misc/fsck.c
index 1f6ec7d9..91edbf17 100644
--- a/misc/fsck.c
+++ b/misc/fsck.c
@@ -547,6 +547,8 @@ static int kill_all(int signum)
         for (inst = instance_list; inst; inst = inst->next) {
                 if (inst->flags & FLAG_DONE)
                         continue;
+               if (inst->pid == -1)
+                       continue;
                 kill(inst->pid, signum);
                 n++;
         }
> 
> 
> diff --git a/misc/fsck.c b/misc/fsck.c
> index 1f6ec7d9..8fae7730 100644
> --- a/misc/fsck.c
> +++ b/misc/fsck.c
> @@ -497,9 +497,10 @@ static int execute(const char *type, const char *device, const char *mntpt,
>   	}
>   
>   	/* Fork and execute the correct program. */
> -	if (noexecute)
> +	if (noexecute) {
>   		pid = -1;
> -	else if ((pid = fork()) < 0) {
> +		inst->flags |= FLAG_DONE;
> +	} else if ((pid = fork()) < 0) {
>   		perror("fork");
>   		free(inst);
>   		return errno;
> @@ -544,6 +545,9 @@ static int kill_all(int signum)
>   	struct fsck_instance *inst;
>   	int	n = 0;
>   
> +	if (noexecute)
> +		return 0;
> +
>   	for (inst = instance_list; inst; inst = inst->next) {
>   		if (inst->flags & FLAG_DONE)
>   			continue;
regards,
Zhan Chengbin