[syzbot] [ocfs2?] general protection fault in ocfs2_assure_trans_credits

From: syzbot
Date: Mon Apr 07 2025 - 16:33:31 EST

Hello,

syzbot found the following issue on:

HEAD commit: a2cc6ff5ec8f Merge tag 'firewire-updates-6.15' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1011d404580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fe3b5e6a2cb1cc2
dashboard link: https://syzkaller.appspot.com/bug?extid=8497452549365f8d1c37
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=17b8c94c580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11e927cf980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-a2cc6ff5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c58c1555aab7/vmlinux-a2cc6ff5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/61fb9d013359/bzImage-a2cc6ff5.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/778ae9eeaba6/mount_3.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=1268194c580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8497452549365f8d1c37@xxxxxxxxxxxxxxxxxxxxxxxxx

(syz-executor410,5357,0):ocfs2_extend_trans:438 ERROR: status = -30
(syz-executor410,5357,0):ocfs2_try_to_merge_extent:3817 ERROR: status = -30
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 5357 Comm: syz-executor410 Not tainted 6.14.0-syzkaller-12966-ga2cc6ff5ec8f #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:jbd2_handle_buffer_credits include/linux/jbd2.h:-1 [inline]
RIP: 0010:ocfs2_assure_trans_credits+0x80/0x3a0 fs/ocfs2/journal.c:457
Code: 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 45 11 65 fe 49 8b 1c 24 eb 08 e8 ba ec fa fd 4c 89 e3 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 21 11 65 fe 48 8b 2b 49 8d 7c 24
RSP: 0018:ffffc9000d466e88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888000ab8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888047cd0b24 R08: ffffffff83c86a9b R09: ffffffff83bd1493
R10: 0000000000000006 R11: ffff888000ab8000 R12: ffff888047cd0b00
R13: dffffc0000000000 R14: 000000000000000a R15: ffff888040fb3b80
FS: 00007fe48a49b6c0(0000) GS:ffff88808c599000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe48a47ad58 CR3: 0000000035e16000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ocfs2_dio_end_io_write fs/ocfs2/aops.c:2342 [inline]
ocfs2_dio_end_io+0xc36/0x1330 fs/ocfs2/aops.c:2401
dio_complete+0x250/0x720 fs/direct-io.c:281
__blockdev_direct_IO+0x3baf/0x4540 fs/direct-io.c:1303
ocfs2_direct_IO+0x255/0x2c0 fs/ocfs2/aops.c:2438
generic_file_direct_write+0x1e8/0x400 mm/filemap.c:4036
__generic_file_write_iter+0x126/0x230 mm/filemap.c:4205
ocfs2_file_write_iter+0x190f/0x20d0 fs/ocfs2/file.c:2469
do_iter_readv_writev+0x71f/0x9d0 fs/read_write.c:-1
vfs_writev+0x38d/0xbc0 fs/read_write.c:1055
do_pwritev fs/read_write.c:1151 [inline]
__do_sys_pwritev2 fs/read_write.c:1209 [inline]
__se_sys_pwritev2+0x1b8/0x2d0 fs/read_write.c:1200
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe48a508a99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fe48a49b208 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007fe48a595718 RCX: 00007fe48a508a99
RDX: 0000000000000001 RSI: 0000200000000240 RDI: 000000000000000a
RBP: 00007fe48a595710 R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000007800 R11: 0000000000000246 R12: 00007fe48a56158c
R13: 0000200000000000 R14: 0000200000000180 R15: 0000200000000240
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jbd2_handle_buffer_credits include/linux/jbd2.h:-1 [inline]
RIP: 0010:ocfs2_assure_trans_credits+0x80/0x3a0 fs/ocfs2/journal.c:457
Code: 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 45 11 65 fe 49 8b 1c 24 eb 08 e8 ba ec fa fd 4c 89 e3 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 21 11 65 fe 48 8b 2b 49 8d 7c 24
RSP: 0018:ffffc9000d466e88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888000ab8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888047cd0b24 R08: ffffffff83c86a9b R09: ffffffff83bd1493
R10: 0000000000000006 R11: ffff888000ab8000 R12: ffff888047cd0b00
R13: dffffc0000000000 R14: 000000000000000a R15: ffff888040fb3b80
FS: 00007fe48a49b6c0(0000) GS:ffff88808c599000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe48a544990 CR3: 0000000035e16000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 89 e0 mov %esp,%eax
2: 48 c1 e8 03 shr $0x3,%rax
6: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1)
b: 74 08 je 0x15
d: 4c 89 e7 mov %r12,%rdi
10: e8 45 11 65 fe call 0xfe65115a
15: 49 8b 1c 24 mov (%r12),%rbx
19: eb 08 jmp 0x23
1b: e8 ba ec fa fd call 0xfdfaecda
20: 4c 89 e3 mov %r12,%rbx
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 21 11 65 fe call 0xfe65115a
39: 48 8b 2b mov (%rbx),%rbp
3c: 49 rex.WB
3d: 8d .byte 0x8d
3e: 7c 24 jl 0x64


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