syzbot


WARNING in mb_find_extent

Status: upstream: reported C repro on 2023/01/02 05:18
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+92c41eb9476db3a702b7@syzkaller.appspotmail.com
First crash: 494d, last: 432d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in mb_find_extent ext4 C error error 135 456d 497d 22/26 fixed on 2023/07/01 16:05
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2023/03/05 01:40 29m bisect fix linux-4.14.y job log (0) log
2023/02/03 00:48 28m bisect fix linux-4.14.y job log (0) log

Sample crash report:
======================================================
EXT4-fs (loop0): Quota format mount options ignored when QUOTA feature is enabled
EXT4-fs: Warning: mounting with data=journal disables delayed allocation and O_DIRECT support!
EXT4-fs (loop0): orphan cleanup on readonly fs
------------[ cut here ]------------
WARNING: CPU: 0 PID: 7970 at fs/ext4/mballoc.c:1560 mb_find_extent+0x5a2/0xa30 fs/ext4/mballoc.c:1560
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7970 Comm: syz-executor455 Not tainted 4.14.302-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 panic+0x1f9/0x42d kernel/panic.c:183
 __warn.cold+0x20/0x44 kernel/panic.c:547
 report_bug+0x208/0x250 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:967
RIP: 0010:mb_find_extent+0x5a2/0xa30 fs/ext4/mballoc.c:1560
RSP: 0018:ffff8880b3b16a40 EFLAGS: 00010297
RAX: ffff8880b2c3e100 RBX: 0000000000000029 RCX: ffff8880b3152900
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffff8880b3152918
RBP: ffff8880b3b16c88 R08: 1ffff1101662a523 R09: 0000000000000005
R10: 0000000000000000 R11: ffff8880b2c3e100 R12: 0000000000000000
R13: ffff8880b3b16b80 R14: ffff8880b3b16b8c R15: 0000000000000041
 ext4_mb_complex_scan_group+0x2c3/0x810 fs/ext4/mballoc.c:1977
 ext4_mb_regular_allocator+0x82b/0xe70 fs/ext4/mballoc.c:2231
 ext4_mb_new_blocks+0x1969/0x3db0 fs/ext4/mballoc.c:4604
 ext4_ext_map_blocks+0x2845/0x6b10 fs/ext4/extents.c:4505
 ext4_map_blocks+0x675/0x1730 fs/ext4/inode.c:656
 ext4_getblk+0x98/0x420 fs/ext4/inode.c:992
 ext4_bread+0x6c/0x1b0 fs/ext4/inode.c:1042
 ext4_quota_write+0x187/0x420 fs/ext4/super.c:5902
 write_blk+0x106/0x1e0 fs/quota/quota_tree.c:72
 get_free_dqblk+0xf3/0x330 fs/quota/quota_tree.c:133
 do_insert_tree+0x34b/0x1060 fs/quota/quota_tree.c:343
 do_insert_tree+0xe85/0x1060 fs/quota/quota_tree.c:374
 do_insert_tree+0xe85/0x1060 fs/quota/quota_tree.c:374
 do_insert_tree+0xe85/0x1060 fs/quota/quota_tree.c:374
 dq_insert_tree fs/quota/quota_tree.c:400 [inline]
 qtree_write_dquot+0x18a/0x4e0 fs/quota/quota_tree.c:419
 v2_write_dquot+0x10f/0x240 fs/quota/quota_v2.c:359
 dquot_acquire+0x220/0x470 fs/quota/dquot.c:436
 ext4_acquire_dquot+0x1b8/0x290 fs/ext4/super.c:5558
 dqget+0x6a0/0xe90 fs/quota/dquot.c:897
 __dquot_initialize+0x2fb/0xa70 fs/quota/dquot.c:1471
 ext4_orphan_cleanup fs/ext4/super.c:2606 [inline]
 ext4_fill_super+0x7261/0xb3c0 fs/ext4/super.c:4475
 mount_bdev+0x2b3/0x360 fs/super.c:1134
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2572 [inline]
 do_mount+0xe65/0x2a30 fs/namespace.c:2905
 SYSC_mount fs/namespace.c:3121 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3098
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7f2cdbb56c3a
RSP: 002b:00007fffcab1e078 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2cdbb56c3a
RDX: 0000000020000040 RSI: 0000000020000500 RDI: 00007fffcab1e080
RBP: 00007fffcab1e080 R08: 00007fffcab1e0c0 R09: 0000000000002dd1
R10: 0000000000000047 R11: 0000000000000206 R12: 0000000000000004
R13: 000055555568c2c0 R14: 00007fffcab1e0c0 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/02 05:18 linux-4.14.y c4215ee4771b ab32d508 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-4-14 WARNING in mb_find_extent
* Struck through repros no longer work on HEAD.