[syzbot] [ext4?] kernel panic: EXT4-fs (device loop0): panic forced after error (3)

syzbot
2023-08-16T22:48:49Z

Hello,

syzbot found the following issue on:

HEAD commit: ae545c3283dc Merge tag 'gpio-fixes-for-v6.5-rc6' of git://..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=13e5d553a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=171b698bc2e613cf
dashboard link: https://syzkaller.appspot.com/bug?extid=27eece6916b914a49ce7
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=13433207a80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=109cd837a80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3b9bad020898/disk-ae545c32.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4073566d0a4b/vmlinux-ae545c32.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b163e2a2c47c/bzImage-ae545c32.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/004395fabe81/mount_0.gz

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12890d53a80000
final oops: https://syzkaller.appspot.com/x/report.txt?x=11890d53a80000
console output: https://syzkaller.appspot.com/x/log.txt?x=16890d53a80000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+27eece6916b914a49ce7@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 512
ext2: Unknown parameter '����'
EXT4-fs (loop0): feature flags set on rev 0 fs, running e2fsck is recommended
EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended
EXT4-fs warning (device loop0): ext4_update_dynamic_rev:1084: updating to rev 1 because of new feature flag, running e2fsck is recommended
EXT4-fs error (device loop0): ext4_validate_block_bitmap:430: comm syz-executor211: bg 0: block 46: invalid block bitmap
Kernel panic - not syncing: EXT4-fs (device loop0): panic forced after error
CPU: 1 PID: 5061 Comm: syz-executor211 Not tainted 6.5.0-rc5-syzkaller-00353-gae545c3283dc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
panic+0x30f/0x770 kernel/panic.c:340
ext4_handle_error+0x84e/0x8b0 fs/ext4/super.c:685
__ext4_error+0x277/0x3b0 fs/ext4/super.c:776
ext4_validate_block_bitmap+0xdf5/0x1200 fs/ext4/balloc.c:429
ext4_read_block_bitmap+0x40/0x80 fs/ext4/balloc.c:595
ext4_mb_clear_bb fs/ext4/mballoc.c:6503 [inline]
ext4_free_blocks+0xfd3/0x2e20 fs/ext4/mballoc.c:6748
ext4_remove_blocks fs/ext4/extents.c:2545 [inline]
ext4_ext_rm_leaf fs/ext4/extents.c:2710 [inline]
ext4_ext_remove_space+0x216e/0x4d90 fs/ext4/extents.c:2958
ext4_ext_truncate+0x164/0x1f0 fs/ext4/extents.c:4408
ext4_truncate+0xa0a/0x1150 fs/ext4/inode.c:4127
ext4_process_orphan+0x1aa/0x2d0 fs/ext4/orphan.c:339
ext4_orphan_cleanup+0xb71/0x1400 fs/ext4/orphan.c:474
__ext4_fill_super fs/ext4/super.c:5577 [inline]
ext4_fill_super+0x63ef/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: 0033:0x7f86c9eb1a99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc2eecbce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f86c9eb1a99
RDX: 00000000200001c0 RSI: 00000000200006c0 RDI: 0000000020000640
RBP: 000000000000ec37 R08: 0000000000000000 R09: 00005555562044c0
R10: 000000003f000000 R11: 0000000000000246 R12: 00007ffc2eecbd10
R13: 00007ffc2eecbcfc R14: 431bde82d7b634db R15: 00007f86c9efa03b
</TASK>
Kernel Offset: disabled
Rebooting in 86400 seconds..

---
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