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From: Al Viro <viro@zeniv.linux.org.uk>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexey Gladkov <gladkov.alexey@gmail.com>,
	syzbot <syzbot+4abac52934a48af5ff19@syzkaller.appspotmail.com>,
	adobriyan@gmail.com, keescook@chromium.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: Re: [PATCH] proc: s_fs_info may be NULL when proc_kill_sb is called
Date: Wed, 10 Jun 2020 18:41:52 +0100	[thread overview]
Message-ID: <20200610174152.GS23230@ZenIV.linux.org.uk> (raw)
In-Reply-To: <87mu5azvxl.fsf@x220.int.ebiederm.org>

On Wed, Jun 10, 2020 at 12:12:54PM -0500, Eric W. Biederman wrote:

> >  {
> >  	struct proc_fs_info *fs_info = proc_sb_info(sb);
> >  
> > -	if (fs_info->proc_self)
> > -		dput(fs_info->proc_self);
> > +	if (fs_info) {
> > +		if (fs_info->proc_self)
> > +			dput(fs_info->proc_self);
> >  
> > -	if (fs_info->proc_thread_self)
> > -		dput(fs_info->proc_thread_self);
> > +		if (fs_info->proc_thread_self)
> > +			dput(fs_info->proc_thread_self);
> > +
> > +		put_pid_ns(fs_info->pid_ns);
> > +		kfree(fs_info);

While we are at it, dput(NULL) is an explicit no-op.

  reply	other threads:[~2020-06-10 17:42 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-10 10:56 general protection fault in proc_kill_sb syzbot
2020-06-10 11:23 ` Tetsuo Handa
2020-06-10 11:44   ` Alexey Gladkov
2020-06-10 13:04 ` [PATCH] proc: s_fs_info may be NULL when proc_kill_sb is called Alexey Gladkov
2020-06-10 17:12   ` Eric W. Biederman
2020-06-10 17:41     ` Al Viro [this message]
2020-06-10 18:35   ` [PATCH v2] " Alexey Gladkov
2020-06-10 20:17     ` Eric W. Biederman

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