syzbot


kernel BUG in ocfs2_reserve_suballoc_bits (2)

Status: upstream: reported on 2025/09/08 12:17
Reported-by: syzbot+487e39304129321dd253@syzkaller.appspotmail.com
First crash: 4d17h, last: 4d17h
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 kernel BUG in ocfs2_reserve_suballoc_bits -1 1 179d 179d 0/3 auto-obsoleted due to no activity on 2025/06/25 12:34
upstream kernel BUG in ocfs2_reserve_suballoc_bits ocfs2 -1 C 344 2d13h 315d 0/29 upstream: reported C repro on 2024/11/01 20:51

Sample crash report:
ocfs2: Mounting device (7,2) on (node local, slot 0) with writeback data mode.
------------[ cut here ]------------
kernel BUG at fs/ocfs2/suballoc.c:800!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 5047 Comm: syz.2.143 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ocfs2_reserve_suballoc_bits+0x327c/0x3cd4 fs/ocfs2/suballoc.c:800
lr : ocfs2_reserve_suballoc_bits+0x327c/0x3cd4 fs/ocfs2/suballoc.c:800
sp : ffff8000215161c0
x29: ffff800021516640 x28: ffff0000d2215300 x27: ffff0000d2215310
x26: ffff7000042a2c60 x25: 00000000ffffffff x24: 000000000000ffff
x23: 0000000000000001 x22: ffff0000f73e1e00 x21: dfff800000000000
x20: 0000000000000000 x19: 0000000000000001 x18: ffff800011abbcc0
x17: 1fffe00033edbb7e x16: ffff8000082e7b10 x15: 0000000000000002
x14: 000000001195710c x13: 1ffff00002a180b1 x12: 0000000000080000
x11: 000000000007ffff x10: ffff800028e7a000 x9 : ffff800009db3680
x8 : 0000000000080000 x7 : ffff800009d46f10 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff800011a318fc
x2 : 0000000000000000 x1 : 00000000ffffffff x0 : 0000000000000000
Call trace:
 ocfs2_reserve_suballoc_bits+0x327c/0x3cd4 fs/ocfs2/suballoc.c:800
 ocfs2_reserve_cluster_bitmap_bits fs/ocfs2/suballoc.c:1128 [inline]
 ocfs2_reserve_clusters_with_limit+0x290/0x9e0 fs/ocfs2/suballoc.c:1173
 ocfs2_reserve_clusters fs/ocfs2/suballoc.c:1223 [inline]
 ocfs2_lock_allocators+0x27c/0x518 fs/ocfs2/suballoc.c:2669
 ocfs2_write_begin_nolock+0x1d08/0x3ab4 fs/ocfs2/aops.c:1740
 ocfs2_dio_wr_get_block+0x75c/0x14e0 fs/ocfs2/aops.c:2239
 get_more_blocks fs/direct-io.c:665 [inline]
 do_direct_IO fs/direct-io.c:953 [inline]
 __blockdev_direct_IO+0x112c/0x318c fs/direct-io.c:1266
 ocfs2_direct_IO+0x208/0x280 fs/ocfs2/aops.c:2468
 generic_file_direct_write+0x31c/0x620 mm/filemap.c:3770
 __generic_file_write_iter+0x1bc/0x37c mm/filemap.c:3930
 ocfs2_file_write_iter+0x1300/0x1bf4 fs/ocfs2/file.c:2469
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5ac/0x7c4 fs/read_write.c:584
 ksys_write+0x120/0x210 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 54ff1a8b 97ac8cf3 17fff8d2 979bb92f (d4210000) 
---[ end trace 0000000000000000 ]---

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/08 12:16 linux-6.1.y 28c695c365e1 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in ocfs2_reserve_suballoc_bits
* Struck through repros no longer work on HEAD.