[syzbot] [ext4?] kernel BUG in ext4_enable_quotas

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 995b406c7e97 Merge tag 'csky-for-linus-6.5' of https://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15fdda4f280000
kernel config: https://syzkaller.appspot.com/x/.config?x=71a52faf60231bc7
dashboard link: https://syzkaller.appspot.com/bug?extid=693985588d7a5e439483
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/01122b567c73/disk-995b406c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/75b7a37e981e/vmlinux-995b406c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/758b5afcf092/bzImage-995b406c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+693985...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/ext4/super.c:7010!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 27977 Comm: syz-executor.2 Not tainted 6.4.0-syzkaller-10098-g995b406c7e97 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
RIP: 0010:ext4_quota_enable fs/ext4/super.c:7010 [inline]
RIP: 0010:ext4_enable_quotas+0xb7a/0xb90 fs/ext4/super.c:7057
Code: ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 3a f7 ff ff 49 89 d6 48 89 df e8 03 10 99 ff 4c 89 f2 e9 27 f7 ff ff e8 46 60 40 ff <0f> 0b e8 3f 60 40 ff 0f 0b e8 18 6e 6e 08 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc9000392f880 EFLAGS: 00010293
RAX: ffffffff824b91aa RBX: 0000000000000000 RCX: ffff88803c1d8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000392fa50 R08: ffffffff824b8aa4 R09: 1ffff11010674957
R10: dffffc0000000000 R11: ffffed1010674958 R12: 0000000000000001
R13: 0000000000000000 R14: ffff88807f545464 R15: dffffc0000000000
FS: 00007f5112313700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002007f000 CR3: 000000002cb28000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__ext4_fill_super fs/ext4/super.c:5562 [inline]
ext4_fill_super+0x6157/0x6ce0 fs/ext4/super.c:5696
get_tree_bdev+0x468/0x6c0 fs/super.c:1318
vfs_get_tree+0x8c/0x270 fs/super.c:1519
do_new_mount+0x28f/0xae0 fs/namespace.c:3335
do_mount fs/namespace.c:3675 [inline]
__do_sys_mount fs/namespace.c:3884 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f511168d8ba
Code: 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5112312f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000000005d8 RCX: 00007f511168d8ba
RDX: 0000000020000580 RSI: 00000000200005c0 RDI: 00007f5112312fe0
RBP: 00007f5112313020 R08: 00007f5112313020 R09: 0000000001008002
R10: 0000000001008002 R11: 0000000000000202 R12: 0000000020000580
R13: 00000000200005c0 R14: 00007f5112312fe0 R15: 0000000020000100
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_quota_enable fs/ext4/super.c:7010 [inline]
RIP: 0010:ext4_enable_quotas+0xb7a/0xb90 fs/ext4/super.c:7057
Code: ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 3a f7 ff ff 49 89 d6 48 89 df e8 03 10 99 ff 4c 89 f2 e9 27 f7 ff ff e8 46 60 40 ff <0f> 0b e8 3f 60 40 ff 0f 0b e8 18 6e 6e 08 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc9000392f880 EFLAGS: 00010293
RAX: ffffffff824b91aa RBX: 0000000000000000 RCX: ffff88803c1d8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000392fa50 R08: ffffffff824b8aa4 R09: 1ffff11010674957
R10: dffffc0000000000 R11: ffffed1010674958 R12: 0000000000000001
R13: 0000000000000000 R14: ffff88807f545464 R15: dffffc0000000000
FS: 00007f5112313700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d324000 CR3: 000000002cb28000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

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https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the bug is already fixed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to change bug's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 89bf6209cad6 Merge tag 'devicetree-fixes-for-6.5-2' of git..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=120c47f7a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=1b32f62c755c3a9c
dashboard link: https://syzkaller.appspot.com/bug?extid=693985588d7a5e439483
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ba1fefa80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1636640fa80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/57b9a06bad82/disk-89bf6209.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a5bb3483e19d/vmlinux-89bf6209.xz
kernel image: https://storage.googleapis.com/syzbot-assets/905ebaa6ecf8/bzImage-89bf6209.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/20b0f7175bae/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/eda4e74724f3/mount_1.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+693985...@syzkaller.appspotmail.com

kernel BUG at fs/ext4/super.c:7010!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 1 PID: 5086 Comm: syz-executor143 Not tainted 6.5.0-rc7-syzkaller-00018-g89bf6209cad6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023

RIP: 0010:ext4_quota_enable fs/ext4/super.c:7010 [inline]
RIP: 0010:ext4_enable_quotas+0xb7a/0xb90 fs/ext4/super.c:7057

Code: ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 3a f7 ff ff 49 89 d6 48 89 df e8 13 07 99 ff 4c 89 f2 e9 27 f7 ff ff e8 36 35 40 ff <0f> 0b e8 2f 35 40 ff 0f 0b e8 e8 4d 71 08 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90003d7f880 EFLAGS: 00010293
RAX: ffffffff824b82fa RBX: 0000000000000000 RCX: ffff88802cd08000

RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000

RBP: ffffc90003d7fa50 R08: ffffffff824b7bf4 R09: 1ffff1100eadb457
R10: dffffc0000000000 R11: ffffed100eadb458 R12: 0000000000000001
R13: 0000000000000001 R14: ffff88801675d464 R15: dffffc0000000000
FS: 00007fc13f7ec6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fc13f8b86c0 CR3: 000000001635a000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__ext4_fill_super fs/ext4/super.c:5562 [inline]
ext4_fill_super+0x6157/0x6ce0 fs/ext4/super.c:5696
get_tree_bdev+0x468/0x6c0 fs/super.c:1318
vfs_get_tree+0x8c/0x270 fs/super.c:1519
do_new_mount+0x28f/0xae0 fs/namespace.c:3335
do_mount fs/namespace.c:3675 [inline]
__do_sys_mount fs/namespace.c:3884 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

RIP: 0033:0x7fc13f83111a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc13f7ec088 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc13f83111a
RDX: 00000000200005c0 RSI: 0000000020000000 RDI: 00007fc13f7ec0a0
RBP: 00007fc13f7ec0a0 R08: 00007fc13f7ec0e0 R09: 00000000000004d4
R10: 0000000000200810 R11: 0000000000000206 R12: 00007fc13f7ec0e0
R13: 0000000000200810 R14: 0000000000000003 R15: 0000000000040000

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_quota_enable fs/ext4/super.c:7010 [inline]
RIP: 0010:ext4_enable_quotas+0xb7a/0xb90 fs/ext4/super.c:7057

Code: ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 3a f7 ff ff 49 89 d6 48 89 df e8 13 07 99 ff 4c 89 f2 e9 27 f7 ff ff e8 36 35 40 ff <0f> 0b e8 2f 35 40 ff 0f 0b e8 e8 4d 71 08 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90003d7f880 EFLAGS: 00010293
RAX: ffffffff824b82fa RBX: 0000000000000000 RCX: ffff88802cd08000

RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000

RBP: ffffc90003d7fa50 R08: ffffffff824b7bf4 R09: 1ffff1100eadb457
R10: dffffc0000000000 R11: ffffed100eadb458 R12: 0000000000000001
R13: 0000000000000001 R14: ffff88801675d464 R15: dffffc0000000000
FS: 00007fc13f7ec6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000555556776778 CR3: 000000001635a000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 6f861765464f43a71462d52026fbddfc858239a5
Author: Jan Kara <ja...@suse.cz>
Date: Wed Nov 1 17:43:10 2023 +0000

fs: Block writes to mounted block devices

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147e5b20180000
start commit: 89bf6209cad6 Merge tag 'devicetree-fixes-for-6.5-2' of git..
git tree: upstream

kernel config: https://syzkaller.appspot.com/x/.config?x=1b32f62c755c3a9c
dashboard link: https://syzkaller.appspot.com/bug?extid=693985588d7a5e439483

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ba1fefa80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1636640fa80000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: fs: Block writes to mounted block devices

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Jan Kara]

On Sat 10-02-24 06:59:05, syzbot wrote:
> syzbot suspects this issue was fixed by commit:
>
> commit 6f861765464f43a71462d52026fbddfc858239a5
> Author: Jan Kara <ja...@suse.cz>
> Date: Wed Nov 1 17:43:10 2023 +0000
>
> fs: Block writes to mounted block devices
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=147e5b20180000
> start commit: 89bf6209cad6 Merge tag 'devicetree-fixes-for-6.5-2' of git..
> git tree: upstream
> kernel config: https://syzkaller.appspot.com/x/.config?x=1b32f62c755c3a9c
> dashboard link: https://syzkaller.appspot.com/bug?extid=693985588d7a5e439483
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ba1fefa80000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1636640fa80000
>
> If the result looks correct, please mark the issue as fixed by replying with:

The syzbot reproducer seems to mess with multiple ext4 mounts stacked on
one another and the loop device as well. Quite likely it managed to corrupt
the mounted filesystem. So:

#syz fix: fs: Block writes to mounted block devices

Honza
--
Jan Kara <ja...@suse.com>
SUSE Labs, CR