From: Christian Brauner <brauner@kernel.org>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: syzbot <syzbot+52cd651546d11d2af06b@syzkaller.appspotmail.com>,
"James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>,
Al Viro <viro@zeniv.linux.org.uk>,
jk@ozlabs.org, linux-efi@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [fs?] [efi?] BUG: unable to handle kernel paging request in alloc_fs_context
Date: Thu, 22 May 2025 14:24:10 +0200 [thread overview]
Message-ID: <20250522-exotisch-chloren-3fa7b7ce5266@brauner> (raw)
In-Reply-To: <CAMj1kXEg88Q5GCV+YW13UT4eDEzMpnKW8ReJNDjLqX7xeXaw=w@mail.gmail.com>
On Wed, May 21, 2025 at 07:28:34PM +0200, Ard Biesheuvel wrote:
> (cc James, Al, Christian)
>
> Please see the splat below.
>
> The NULL dereference is due to get_cred() in alloc_fs_context()
> attempting to increment current->cred->usage while current->cred ==
> NULL, and this is a result of the fact that PM notifier call chain is
> called while the task is exiting.
>
> IIRC, the intent was for commit
>
> 11092db5b573 efivarfs: fix NULL dereference on resume
>
> to be replaced at some point with something more robust; might that
> address this issue as well?
Yes. It's in the merge queue for v6.16 which kills off all that
vfs_kern_mount() stuff.
next prev parent reply other threads:[~2025-05-22 12:24 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-05-11 17:44 [syzbot] [fs?] [efi?] BUG: unable to handle kernel paging request in alloc_fs_context syzbot
2025-05-21 17:28 ` Ard Biesheuvel
2025-05-22 12:24 ` Christian Brauner [this message]
2025-05-22 13:47 ` Ard Biesheuvel
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