kernel BUG in ocfs2_reserve_suballoc_bits

Status: upstream: reported C repro on 2024/11/01 20:51
Subsystems: ocfs2
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+fd05de09d1267725aa95@syzkaller.appspotmail.com
First crash: 670d, last: 4d00h
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
9c3ee2d7 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ kernel BUG in ocfs2_reserve_suballoc_bits 2026/05/24 04:24 2026/05/24 04:24 2026/05/24 05:10 c69befb3
▶ ▼ Discussions (4)
Title Replies (including bot) Last reply
[syzbot] Monthly ocfs2 report (Aug 2026) 0 (1) 2026/08/11 12:32
[syzbot] Monthly ocfs2 report (Jul 2026) 0 (1) 2026/07/11 12:32
[syzbot] Monthly ocfs2 report (Jun 2026) 0 (1) 2026/06/10 04:32
[syzbot] [ocfs2?] kernel BUG in ocfs2_reserve_suballoc_bits 0 (4) 2025/10/22 15:05
▶ ▼ Similar bugs (4)
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 530d 530d 0/3 auto-obsoleted due to no activity on 2025/06/25 12:34
linux-6.1 kernel BUG in ocfs2_reserve_suballoc_bits (2) -1 syz, C error 11 130d 355d 0/3 upstream: reported C repro on 2025/09/08 12:17
linux-5.15 kernel BUG in ocfs2_reserve_suballoc_bits -1 1 348d 348d 0/3 auto-obsoleted due to no activity on 2025/12/24 10:29
linux-5.15 kernel BUG in ocfs2_reserve_suballoc_bits (2) -1 1 243d 243d 0/3 auto-obsoleted due to no activity on 2026/04/08 06:32
▶ ▼ Last patch testing requests (7)
Created Duration User Patch Repo Result
2026/02/02 23:10 16m retest repro upstream error
2025/10/22 15:05 14m dmantipov@yandex.ru patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 552c50713f273b494ac6c77052032a49bc9255e2 report log
2025/09/03 16:05 21m retest repro upstream no crash log
2025/07/21 09:14 15m retest repro upstream report log
2025/06/18 03:34 14m retest repro upstream report log
2025/04/09 03:16 14m retest repro upstream report log
2024/11/20 08:14 19m dmantipov@yandex.ru patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git bf9aa14fc523d2763fc9a10672a709224e8fcaf4 report log

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/ocfs2/suballoc.c:806!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5473 Comm: syz.0.16 Not tainted 6.16.0-rc4-syzkaller-00348-g772b78c2abd8 #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:ocfs2_reserve_suballoc_bits+0x3f38/0x4640 fs/ocfs2/suballoc.c:806
Code: 78 e9 23 f2 ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 82 dd ff ff 4c 89 f7 e8 b3 e9 7d fe e9 75 dd ff ff e8 39 66 1a fe 90 <0f> 0b 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 3c df ff ff 4c 89 ff
RSP: 0018:ffffc900029fdca0 EFLAGS: 00010293
RAX: ffffffff83a5bfc7 RBX: ffff88804e5a9e00 RCX: ffff888031302440
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: ffffc900029fe170 R08: ffffffff8fa1e5f7 R09: 1ffffffff1f43cbe
R10: dffffc0000000000 R11: fffffbfff1f43cbf R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888042d64fb8 R15: 00000000ffffffff
FS:  00007f1bd7d886c0(0000) GS:ffff88808d21d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1bd7d65fb8 CR3: 000000004f0a4000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ocfs2_reserve_cluster_bitmap_bits+0xc4/0x1c0 fs/ocfs2/suballoc.c:1134
 ocfs2_local_alloc_reserve_for_window fs/ocfs2/localalloc.c:1108 [inline]
 ocfs2_local_alloc_slide_window fs/ocfs2/localalloc.c:1244 [inline]
 ocfs2_reserve_local_alloc_bits+0x88f/0x24e0 fs/ocfs2/localalloc.c:669
 ocfs2_reserve_clusters_with_limit+0x1be/0xba0 fs/ocfs2/suballoc.c:1168
 ocfs2_reserve_clusters fs/ocfs2/suballoc.c:1229 [inline]
 ocfs2_lock_allocators+0x2fa/0x5c0 fs/ocfs2/suballoc.c:2772
 ocfs2_write_begin_nolock+0x2279/0x4340 fs/ocfs2/aops.c:1718
 ocfs2_dio_wr_get_block+0xb6f/0x1770 fs/ocfs2/aops.c:2211
 get_more_blocks fs/direct-io.c:648 [inline]
 do_direct_IO fs/direct-io.c:936 [inline]
 __blockdev_direct_IO+0x16dd/0x33d0 fs/direct-io.c:1243
 ocfs2_direct_IO+0x25f/0x2d0 fs/ocfs2/aops.c:2438
 generic_file_direct_write+0x1d8/0x3e0 mm/filemap.c:4046
 __generic_file_write_iter+0x11d/0x230 mm/filemap.c:4215
 ocfs2_file_write_iter+0x157a/0x1d10 fs/ocfs2/file.c:2469
 iter_file_splice_write+0x937/0x1000 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x101/0x160 fs/splice.c:1158
 splice_direct_to_actor+0x5a5/0xcc0 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0x181/0x270 fs/splice.c:1227
 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1bd6f8e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1bd7d88038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f1bd71b5fa0 RCX: 00007f1bd6f8e929
RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000008
RBP: 00007f1bd7010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 000000080000000c R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1bd71b5fa0 R15: 00007fff8de43e08
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_reserve_suballoc_bits+0x3f38/0x4640 fs/ocfs2/suballoc.c:806
Code: 78 e9 23 f2 ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 82 dd ff ff 4c 89 f7 e8 b3 e9 7d fe e9 75 dd ff ff e8 39 66 1a fe 90 <0f> 0b 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 3c df ff ff 4c 89 ff
RSP: 0018:ffffc900029fdca0 EFLAGS: 00010293
RAX: ffffffff83a5bfc7 RBX: ffff88804e5a9e00 RCX: ffff888031302440
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: ffffc900029fe170 R08: ffffffff8fa1e5f7 R09: 1ffffffff1f43cbe
R10: dffffc0000000000 R11: fffffbfff1f43cbf R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888042d64fb8 R15: 00000000ffffffff
FS:  00007f1bd7d886c0(0000) GS:ffff88808d21d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1bd7d65fb8 CR3: 000000004f0a4000 CR4: 0000000000352ef0

Crashes (532):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/07 09:10 upstream 772b78c2abd8 4f67c4ae .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2 (clean fs)] [mounted in repro #3 (clean fs)] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/26 04:34 upstream 818bebeb63dd 6a91adb4 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/25 08:39 upstream 818bebeb63dd 614e416a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/23 04:09 upstream 818bebeb63dd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/22 12:26 upstream 818bebeb63dd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/22 08:58 upstream 818bebeb63dd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/22 04:01 upstream 818bebeb63dd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/22 00:46 upstream 818bebeb63dd 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/20 16:51 upstream a4ff2be345d0 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/20 11:49 upstream a4ff2be345d0 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/18 11:04 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/16 11:17 upstream 3eb40771c00a 746171ee .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/10 18:23 upstream db2ddb871435 558388e4 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/07 13:10 upstream f9a2394a2348 e4ef95d6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/06 19:50 upstream fcaeecb8b0cd cc56899a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/06 14:53 upstream 0d8395707651 cc56899a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/06 10:14 upstream 0d8395707651 cd5b1963 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/06 08:59 upstream 0d8395707651 cd5b1963 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/06 06:13 upstream 0d8395707651 cd5b1963 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/08/06 06:13 upstream 0d8395707651 cd5b1963 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/29 17:00 upstream fc02acf6ac0c b63596d1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/24 09:00 upstream d326f83e819c 544adce9 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/20 12:34 upstream 1590cf032971 4763fed7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/18 20:19 upstream 1229e2e57a5c 72524a66 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/12 11:29 upstream 44696aa3a489 d78ea535 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/11 15:30 upstream 61c03dfde854 d78ea535 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/11 10:18 upstream 61c03dfde854 d78ea535 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/07/04 18:55 upstream 1e9cdc2ea15a fcece630 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/29 10:03 upstream dc59e4fea9d8 fb92f11c .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/24 14:22 upstream 840ef6c78e6a c1da772e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/24 03:43 upstream f31c00c377cc 042555ff .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/23 06:32 upstream 4708cac0e22c 5a630be6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/23 01:40 upstream 4708cac0e22c 5a630be6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/23 01:39 upstream 4708cac0e22c 5a630be6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/22 19:45 upstream ef0c9f75a195 ab2703f0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/22 15:09 upstream ef0c9f75a195 ab2703f0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/22 01:28 upstream 8cd8cf7a07e5 43bfcdb0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/21 18:09 upstream 390d73adf896 43bfcdb0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/21 02:15 upstream 1a3746ccbb0a 43bfcdb0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/20 07:41 upstream a975094bf98c 43bfcdb0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/19 08:06 upstream 83f1454877cc d7ffd47b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/19 04:55 upstream 83f1454877cc d7ffd47b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/18 20:48 upstream e771677c937d a776b0d0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2026/06/18 13:12 upstream e771677c937d a776b0d0 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2024/11/06 23:11 upstream 7758b206117d 7b852900 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
2024/10/28 20:41 upstream 819837584309 9efb3cc7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in ocfs2_reserve_suballoc_bits
* Struck through repros no longer work on HEAD.