[syzbot] [ext4?] [ocfs2?] KASAN: null-ptr-deref Write in jbd2_journal_update_sb_log_tail

syzbot
2024-08-19T09:32:23Z

Hello,

syzbot found the following issue on:

HEAD commit: c3f2d783a459 Merge tag 'mm-hotfixes-stable-2024-08-17-19-3..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13736c29980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7229118d88b4a71b
dashboard link: https://syzkaller.appspot.com/bug?extid=05b9b39d8bdfe1a0861f
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=15f1b191980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1042525b980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-c3f2d783.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4d927f7c3cfd/vmlinux-c3f2d783.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ea54bdfad24b/bzImage-c3f2d783.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/562379f73e38/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+05b9b39d8bdfe1a0861f@syzkaller.appspotmail.com

(syz-executor198,5100,0):ocfs2_check_volume:2481 ERROR: status = -22
(syz-executor198,5100,0):ocfs2_mount_volume:1821 ERROR: status = -22
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: null-ptr-deref in test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:57 [inline]
BUG: KASAN: null-ptr-deref in trylock_buffer include/linux/buffer_head.h:420 [inline]
BUG: KASAN: null-ptr-deref in lock_buffer include/linux/buffer_head.h:426 [inline]
BUG: KASAN: null-ptr-deref in jbd2_journal_update_sb_log_tail+0x19b/0x360 fs/jbd2/journal.c:1889
Write of size 8 at addr 0000000000000000 by task syz-executor198/5100

CPU: 0 UID: 0 PID: 5100 Comm: syz-executor198 Not tainted 6.11.0-rc3-syzkaller-00338-gc3f2d783a459 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
print_report+0xe8/0x550 mm/kasan/report.c:491
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:57 [inline]
trylock_buffer include/linux/buffer_head.h:420 [inline]
lock_buffer include/linux/buffer_head.h:426 [inline]
jbd2_journal_update_sb_log_tail+0x19b/0x360 fs/jbd2/journal.c:1889
__jbd2_update_log_tail+0x48/0x3f0 fs/jbd2/journal.c:1079
jbd2_cleanup_journal_tail+0x230/0x2d0 fs/jbd2/checkpoint.c:334
jbd2_journal_flush+0x290/0xc10 fs/jbd2/journal.c:2479
ocfs2_journal_shutdown+0x443/0xbe0 fs/ocfs2/journal.c:1081
ocfs2_mount_volume+0x169f/0x1940 fs/ocfs2/super.c:1842
ocfs2_fill_super+0x483b/0x5880 fs/ocfs2/super.c:1084
mount_bdev+0x20a/0x2d0 fs/super.c:1679
legacy_get_tree+0xee/0x190 fs/fs_context.c:662
vfs_get_tree+0x90/0x2a0 fs/super.c:1800
do_new_mount+0x2be/0xb40 fs/namespace.c:3472
do_mount fs/namespace.c:3812 [inline]
__do_sys_mount fs/namespace.c:4020 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f69037ad16a
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffed646ff58 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffed646ff70 RCX: 00007f69037ad16a
RDX: 0000000020004480 RSI: 00000000200044c0 RDI: 00007ffed646ff70
RBP: 0000000000000004 R08: 00007ffed646ffb0 R09: 0000000000004470
R10: 0000000000000000 R11: 0000000000000282 R12: 0000000000000000
R13: 00007ffed646ffb0 R14: 0000000000000003 R15: 0000000001000000
</TASK>
==================================================================

---
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