[ext4?] general protection fault in ext4_fill_super (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6e98b09da931 Merge tag 'net-next-6.4' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1486b6a0280000
kernel config: https://syzkaller.appspot.com/x/.config?x=fb9715c2850514fd
dashboard link: https://syzkaller.appspot.com/bug?extid=bbf0f9a213c94f283a5c
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org ll...@lists.linux.dev nat...@kernel.org ndesau...@google.com tr...@redhat.com ty...@mit.edu]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/77a0431d42ce/disk-6e98b09d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/238d26aa68df/vmlinux-6e98b09d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3aa529effc2f/bzImage-6e98b09d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bbf0f9...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f]
CPU: 0 PID: 15377 Comm: syz-executor.1 Not tainted 6.3.0-syzkaller-07919-g6e98b09da931 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:ext4_quota_capable fs/ext4/ext4.h:3417 [inline]
RIP: 0010:ext4_quota_mode fs/ext4/super.c:4274 [inline]
RIP: 0010:ext4_fill_super+0x37aa/0xb140 fs/ext4/super.c:5678
Code: c1 ea 03 80 3c 02 00 0f 85 41 49 00 00 4d 8b a6 78 06 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 78 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e fd 48 00 00 41 8b 5c 24 78 31
RSP: 0018:ffffc90014e8fb40 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc90003831000
RDX: 000000000000000f RSI: ffffffff82390a60 RDI: 0000000000000078
RBP: ffffffff8a6393c0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000094001 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888038a58000 R15: 0000000000000001
FS: 00007f1b40eb7700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555be4708 CR3: 0000000021ef9000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
get_tree_bdev+0x44a/0x770 fs/super.c:1303
vfs_get_tree+0x8d/0x350 fs/super.c:1510
do_new_mount fs/namespace.c:3039 [inline]
path_mount+0x134b/0x1e40 fs/namespace.c:3369
do_mount fs/namespace.c:3382 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x283/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f1b4008d69a
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:00007f1b40eb6f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000000004b2 RCX: 00007f1b4008d69a
RDX: 0000000020000040 RSI: 0000000020000500 RDI: 00007f1b40eb6fe0
RBP: 00007f1b40eb7020 R08: 00007f1b40eb7020 R09: 0000000000000047
R10: 0000000000000047 R11: 0000000000000202 R12: 0000000020000040
R13: 0000000020000500 R14: 00007f1b40eb6fe0 R15: 0000000020000400
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_quota_capable fs/ext4/ext4.h:3417 [inline]
RIP: 0010:ext4_quota_mode fs/ext4/super.c:4274 [inline]
RIP: 0010:ext4_fill_super+0x37aa/0xb140 fs/ext4/super.c:5678
Code: c1 ea 03 80 3c 02 00 0f 85 41 49 00 00 4d 8b a6 78 06 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 78 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e fd 48 00 00 41 8b 5c 24 78 31
RSP: 0018:ffffc90014e8fb40 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc90003831000
RDX: 000000000000000f RSI: ffffffff82390a60 RDI: 0000000000000078
RBP: ffffffff8a6393c0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000094001 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888038a58000 R15: 0000000000000001
FS: 00007f1b40eb7700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000202f9030 CR3: 0000000021ef9000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: c1 ea 03 shr $0x3,%edx
3: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
7: 0f 85 41 49 00 00 jne 0x494e
d: 4d 8b a6 78 06 00 00 mov 0x678(%r14),%r12
14: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
1b: fc ff df
1e: 49 8d 7c 24 78 lea 0x78(%r12),%rdi
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction
2e: 84 c0 test %al,%al
30: 74 08 je 0x3a
32: 3c 03 cmp $0x3,%al
34: 0f 8e fd 48 00 00 jle 0x4937
3a: 41 8b 5c 24 78 mov 0x78(%r12),%ebx
3f: 31 .byte 0x31


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