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Date:   Tue, 20 Sep 2022 20:24:24 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Ren Zhijie <renzhijie2@huawei.com>
Cc:     ebiederm@xmission.com, keescook@chromium.org, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        tanghui20@huawei.com
Subject: Re: [PATCH] exec: Force binary name when argv is empty
Message-ID: <YyoTaBah0/z+ewWE@ZenIV>
References: <20220920120812.231417-1-renzhijie2@huawei.com>
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On Tue, Sep 20, 2022 at 08:08:12PM +0800, Ren Zhijie wrote:
> From: Hui Tang <tanghui20@huawei.com>
> 
> First run './execv-main execv-child', there is empty in 'COMMAND' column
> when run 'ps -u'.
> 
>  USER       PID %CPU %MEM    VSZ   RSS TTY    [...] TIME COMMAND
>  root       368  0.3  0.0   4388   764 ttyS0        0:00 ./execv-main
>  root       369  0.6  0.0   4520   812 ttyS0        0:00
> 
> The program 'execv-main' as follows:
> 
>  int main(int argc, char **argv)
>  {
>    char *execv_argv[] = {NULL};
>    pid_t pid = fork();
> 
>    if (pid == 0) {
>      execv(argv[1], execv_argv);
>    } else if (pid > 0) {
>      wait(NULL);
>    }
>    return 0;
>  }
> 
> So replace empty string ("") added with the name of binary
> when calling execve with a NULL argv.
> 
> Fixes: dcd46d897adb ("exec: Force single empty string when argv is empty")

I don't see the point, to be honest...  You've passed BS argv to execve(),
why would you expect anything pretty from ps(1)?

IOW, where's the bug you are fixing?