Re: [syzbot] [mm?] [fs?] WARNING in path_noexec

[Christian Brauner <brauner@kernel.org>]

On Mon, Jul 07, 2025 at 04:02:32AM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    8d6c58332c7a Add linux-next specific files for 20250703
> git tree:       linux-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=15788582580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=d7dc16394230c170
> dashboard link: https://syzkaller.appspot.com/bug?extid=3de83a9efcca3f0412ee
> compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16ecb3d4580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=153af770580000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/ff731adf5dfa/disk-8d6c5833.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/5c7a3c57e0a1/vmlinux-8d6c5833.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/2f90e7c18574/bzImage-8d6c5833.xz
> 
> The issue was bisected to:
> 
> commit df43ee1b368c791b7042504d2aa90893569b9034
> Author: Christian Brauner <brauner@kernel.org>
> Date:   Wed Jul 2 09:23:55 2025 +0000
> 
>     anon_inode: rework assertions
> 
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=14b373d4580000
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=16b373d4580000
> console output: https://syzkaller.appspot.com/x/log.txt?x=12b373d4580000
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+3de83a9efcca3f0412ee@syzkaller.appspotmail.com
> Fixes: df43ee1b368c ("anon_inode: rework assertions")
> 
> ------------[ cut here ]------------
> WARNING: fs/exec.c:119 at path_noexec+0x1af/0x200 fs/exec.c:118, CPU#1: syz-executor260/5835
> Modules linked in:
> CPU: 1 UID: 0 PID: 5835 Comm: syz-executor260 Not tainted 6.16.0-rc4-next-20250703-syzkaller #0 PREEMPT(full) 
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
> RIP: 0010:path_noexec+0x1af/0x200 fs/exec.c:118

And already we have found one offender whose not raising SB_I_NOEXEC but
using anonymous inodes...

#syz test: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git vfs.fixes