syzbot


general protection fault in ocfs2_prepare_dir_for_insert

Status: upstream: reported C repro on 2025/12/18 14:49
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+4a95be9920417e49cbd5@syzkaller.appspotmail.com
First crash: 25d, last: 24d
Bug presence (2)
Date Name Commit Repro Result
2025/12/18 linux-6.6.y (ToT) 5fa4793a2d2d C [report] general protection fault in ocfs2_prepare_dir_for_insert
2025/12/18 upstream (ToT) ea1013c15392 C Didn't crash
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 general protection fault in ocfs2_prepare_dir_for_insert origin:lts-only 2 C inconclusive 4 24d 24d 0/3 upstream: reported C repro on 2025/12/18 19:22
linux-6.1 BUG: unable to handle kernel paging request in ocfs2_prepare_dir_for_insert origin:upstream missing-backport 8 C inconclusive 20 9d03h 419d 0/3 upstream: reported C repro on 2024/11/19 13:12
upstream general protection fault in ocfs2_prepare_dir_for_insert (2) ocfs2 8 C error 20 37d 216d 29/29 fixed on 2026/01/07 12:29
linux-5.15 BUG: unable to handle kernel paging request in ocfs2_prepare_dir_for_insert 8 C error 15 313d 329d 0/3 auto-obsoleted due to no activity on 2025/05/14 04:21
upstream general protection fault in ocfs2_prepare_dir_for_insert ocfs2 8 C inconclusive 1072 261d 510d 28/29 fixed on 2025/05/06 15:33

Sample crash report:
=======================================================
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 5932 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:ocfs2_find_dir_space_id fs/ocfs2/dir.c:3426 [inline]
RIP: 0010:ocfs2_prepare_dir_for_insert+0x2f23/0x5480 fs/ocfs2/dir.c:4306
Code: 18 00 e9 e1 11 00 00 e8 8b 71 37 fe e9 a9 02 00 00 e8 81 71 37 fe 4c 8b 7c 24 70 49 8d 7e 08 49 8d 5e 09 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 78 20 00 00 4c 2b bc 24 88 00 00 00 48
RSP: 0018:ffffc9000490e240 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000009 RCX: ffff888077d6da00
RDX: 0000000000000000 RSI: ffff88805ba420c8 RDI: 0000000000000008
RBP: ffffc9000490e970 R08: ffffc9000490ebd0 R09: 608b7c562adf3b03
R10: 23ec6d672c196c9a R11: 608b7c562adf3b03 R12: dffffc0000000000
R13: ffff88805b21ddf8 R14: 0000000000000000 R15: 00000001000001c0
FS:  0000555567830500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffebe693bd4 CR3: 00000000773e6000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 __ocfs2_prepare_orphan_dir+0x146/0x2c0 fs/ocfs2/namei.c:2167
 ocfs2_prepare_orphan_dir+0xfa/0x3f0 fs/ocfs2/namei.c:2210
 ocfs2_add_inode_to_orphan+0x1d7/0x710 fs/ocfs2/namei.c:2658
 ocfs2_dio_wr_get_block+0x7dd/0x17a0 fs/ocfs2/aops.c:2211
 get_more_blocks fs/direct-io.c:647 [inline]
 do_direct_IO fs/direct-io.c:935 [inline]
 __blockdev_direct_IO+0x1679/0x3420 fs/direct-io.c:1248
 ocfs2_direct_IO+0x240/0x2b0 fs/ocfs2/aops.c:2468
 generic_file_direct_write+0x1d4/0x3e0 mm/filemap.c:3956
 __generic_file_write_iter+0x11b/0x230 mm/filemap.c:4112
 ocfs2_file_write_iter+0x1582/0x1d00 fs/ocfs2/file.c:2468
 do_iter_readv_writev fs/read_write.c:-1 [inline]
 do_iter_write+0x79a/0xc70 fs/read_write.c:860
 iter_file_splice_write+0x66f/0xc50 fs/splice.c:736
 do_splice_from fs/splice.c:933 [inline]
 direct_splice_actor+0xe8/0x130 fs/splice.c:1142
 splice_direct_to_actor+0x2f0/0x870 fs/splice.c:1088
 do_splice_direct+0x1b7/0x2c0 fs/splice.c:1194
 do_sendfile+0x5dc/0xf70 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64+0x13f/0x190 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1491b8f749
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:00007ffe47dd7af8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f1491de5fa0 RCX: 00007f1491b8f749
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004
RBP: 00007f1491c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1491de5fa0 R14: 00007f1491de5fa0 R15: 0000000000000004
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_find_dir_space_id fs/ocfs2/dir.c:3426 [inline]
RIP: 0010:ocfs2_prepare_dir_for_insert+0x2f23/0x5480 fs/ocfs2/dir.c:4306
Code: 18 00 e9 e1 11 00 00 e8 8b 71 37 fe e9 a9 02 00 00 e8 81 71 37 fe 4c 8b 7c 24 70 49 8d 7e 08 49 8d 5e 09 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 78 20 00 00 4c 2b bc 24 88 00 00 00 48
RSP: 0018:ffffc9000490e240 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000009 RCX: ffff888077d6da00
RDX: 0000000000000000 RSI: ffff88805ba420c8 RDI: 0000000000000008
RBP: ffffc9000490e970 R08: ffffc9000490ebd0 R09: 608b7c562adf3b03
R10: 23ec6d672c196c9a R11: 608b7c562adf3b03 R12: dffffc0000000000
R13: ffff88805b21ddf8 R14: 0000000000000000 R15: 00000001000001c0
FS:  0000555567830500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f59105fe000 CR3: 00000000773e6000 CR4: 00000000003506e0
----------------
Code disassembly (best guess):
   0:	18 00                	sbb    %al,(%rax)
   2:	e9 e1 11 00 00       	jmp    0x11e8
   7:	e8 8b 71 37 fe       	call   0xfe377197
   c:	e9 a9 02 00 00       	jmp    0x2ba
  11:	e8 81 71 37 fe       	call   0xfe377197
  16:	4c 8b 7c 24 70       	mov    0x70(%rsp),%r15
  1b:	49 8d 7e 08          	lea    0x8(%r14),%rdi
  1f:	49 8d 5e 09          	lea    0x9(%r14),%rbx
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 78 20 00 00    	jne    0x20af
  37:	4c 2b bc 24 88 00 00 	sub    0x88(%rsp),%r15
  3e:	00
  3f:	48                   	rex.W

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/18 16:23 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan general protection fault in ocfs2_prepare_dir_for_insert
2025/12/18 15:20 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan general protection fault in ocfs2_prepare_dir_for_insert
2025/12/18 14:51 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ocfs2_prepare_dir_for_insert
2025/12/18 14:51 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ocfs2_prepare_dir_for_insert
2025/12/18 14:49 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ocfs2_prepare_dir_for_insert
2025/12/18 14:48 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in ocfs2_prepare_dir_for_insert
* Struck through repros no longer work on HEAD.