syzbot


stack segment fault in release_metapage

Status: upstream: reported C repro on 2025/08/20 09:22
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+43706fd1eb4c8dccdfe6@syzkaller.appspotmail.com
First crash: 60d, last: 24d
Cause bisection: failed (error log, bisect log)
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [jfs?] stack segment fault in release_metapage 0 (1) 2025/08/20 09:22
Last patch testing requests (2)
Created Duration User Patch Repo Result
2025/09/15 17:10 13m retest repro upstream report log
2025/09/15 17:10 13m retest repro upstream report log

Sample crash report:
Oops: stack segment: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 120 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:folio_flags include/linux/page-flags.h:360 [inline]
RIP: 0010:folio_trylock include/linux/pagemap.h:1096 [inline]
RIP: 0010:folio_lock include/linux/pagemap.h:1132 [inline]
RIP: 0010:release_metapage+0x9e/0xab0 fs/jfs/jfs_metapage.c:870
Code: 04 00 00 e8 14 b9 87 fe 48 c7 c7 df 02 06 8d be 6b 04 00 00 e8 d3 a6 5a fe 2e 2e 2e 31 c0 49 8d 5c 24 08 48 89 dd 48 c1 ed 03 <42> 80 7c 2d 00 00 74 08 48 89 df e8 c2 ef e6 fe 4c 8b 3b 4c 89 fe
RSP: 0018:ffffc9000396f6d8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 1c5c441b1274d300
RDX: ffff88801f38d940 RSI: ffffffff8d218c31 RDI: ffffffff8b620e80
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100b1f58a8 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888058fac518 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881268c2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc9e39f000 CR3: 000000003dcc4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 xtTruncate+0xe84/0x2e70 fs/jfs/jfs_xtree.c:-1
 jfs_free_zero_link+0x33a/0x4a0 fs/jfs/namei.c:759
 jfs_evict_inode+0x363/0x440 fs/jfs/inode.c:153
 evict+0x504/0x9c0 fs/inode.c:810
 txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
 jfs_lazycommit+0x3f1/0xa10 fs/jfs/jfs_txnmgr.c:2733
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:folio_flags include/linux/page-flags.h:360 [inline]
RIP: 0010:folio_trylock include/linux/pagemap.h:1096 [inline]
RIP: 0010:folio_lock include/linux/pagemap.h:1132 [inline]
RIP: 0010:release_metapage+0x9e/0xab0 fs/jfs/jfs_metapage.c:870
Code: 04 00 00 e8 14 b9 87 fe 48 c7 c7 df 02 06 8d be 6b 04 00 00 e8 d3 a6 5a fe 2e 2e 2e 31 c0 49 8d 5c 24 08 48 89 dd 48 c1 ed 03 <42> 80 7c 2d 00 00 74 08 48 89 df e8 c2 ef e6 fe 4c 8b 3b 4c 89 fe
RSP: 0018:ffffc9000396f6d8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 1c5c441b1274d300
RDX: ffff88801f38d940 RSI: ffffffff8d218c31 RDI: ffffffff8b620e80
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100b1f58a8 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888058fac518 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881268c2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc9e39f000 CR3: 000000003dcc4000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	04 00                	add    $0x0,%al
   2:	00 e8                	add    %ch,%al
   4:	14 b9                	adc    $0xb9,%al
   6:	87 fe                	xchg   %edi,%esi
   8:	48 c7 c7 df 02 06 8d 	mov    $0xffffffff8d0602df,%rdi
   f:	be 6b 04 00 00       	mov    $0x46b,%esi
  14:	e8 d3 a6 5a fe       	call   0xfe5aa6ec
  19:	2e 2e 2e 31 c0       	cs cs cs xor %eax,%eax
  1e:	49 8d 5c 24 08       	lea    0x8(%r12),%rbx
  23:	48 89 dd             	mov    %rbx,%rbp
  26:	48 c1 ed 03          	shr    $0x3,%rbp
* 2a:	42 80 7c 2d 00 00    	cmpb   $0x0,0x0(%rbp,%r13,1) <-- trapping instruction
  30:	74 08                	je     0x3a
  32:	48 89 df             	mov    %rbx,%rdi
  35:	e8 c2 ef e6 fe       	call   0xfee6effc
  3a:	4c 8b 3b             	mov    (%rbx),%r15
  3d:	4c 89 fe             	mov    %r15,%rsi

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/01 00:52 upstream 5c3b3264e585 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-upstream-fs stack segment fault in release_metapage
2025/08/20 09:21 upstream b19a97d57c15 79512909 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-upstream-fs stack segment fault in release_metapage
2025/08/21 16:20 upstream 068a56e56fa8 3e79b825 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs stack segment fault in release_metapage
2025/08/20 04:50 upstream b19a97d57c15 79512909 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs stack segment fault in release_metapage
2025/08/10 17:52 upstream 2b38afce25c4 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs stack segment fault in release_metapage
* Struck through repros no longer work on HEAD.