syzbot


general protection fault in btrfs_lookup_csums_bitmap

Status: upstream: reported C repro on 2024/10/23 09:08
Subsystems: btrfs
[Documentation on labels]
Reported-by: syzbot+5d2b33d7835870519b5f@syzkaller.appspotmail.com
First crash: 32d, last: 9d02h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] btrfs: add a sanity check for csum root before fill the data csum 5 (5) 2024/10/29 20:55
[syzbot] [btrfs?] general protection fault in btrfs_lookup_csums_bitmap 1 (3) 2024/10/23 10:38
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/11/02 10:28 13m retest repro upstream report log
2024/10/23 10:18 19m eadavis@qq.com patch upstream OK log

Sample crash report:
workqueue: max_active 32767 requested for btrfs-compressed-write is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-scrub is out of range, clamping between 1 and 512
BTRFS info (device loop0 state CS): scrub: started on devid 1
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000041: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000208-0x000000000000020f]
CPU: 0 UID: 0 PID: 5110 Comm: syz-executor381 Not tainted 6.12.0-rc3-syzkaller-00319-gb04ae0f45168 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:btrfs_lookup_csums_bitmap+0xc4/0x1600 fs/btrfs/file-item.c:615
Code: 8c 24 a8 00 00 00 42 c7 44 31 08 f3 f3 f3 f3 e8 d2 83 e1 fd 48 89 9c 24 88 00 00 00 48 81 c3 08 02 00 00 48 89 d8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 df e8 9d 39 4b fe 4c 8b 2b ba 11 00 00
RSP: 0018:ffffc9000af5f100 EFLAGS: 00010206
RAX: 0000000000000041 RBX: 0000000000000208 RCX: ffff888000cf2440
RDX: 0000000000000000 RSI: ffff888047132080 RDI: 0000000000000000
RBP: ffffc9000af5f290 R08: ffff88801fb3c800 R09: ffffc9000af5f420
R10: dffffc0000000000 R11: ffffed1008e2402e R12: 0000000000500000
R13: ffffc9000af5f420 R14: dffffc0000000000 R15: 0000000000500000
FS:  00005555764d5480(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055572fc64400 CR3: 0000000040a06000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 scrub_find_fill_first_stripe+0xe96/0x1200 fs/btrfs/scrub.c:1618
 queue_scrub_stripe fs/btrfs/scrub.c:1912 [inline]
 scrub_simple_mirror+0x5c6/0x960 fs/btrfs/scrub.c:2144
 scrub_stripe+0xa7a/0x2a60 fs/btrfs/scrub.c:2310
 scrub_chunk+0x2e3/0x470 fs/btrfs/scrub.c:2442
 scrub_enumerate_chunks+0xc4f/0x16a0 fs/btrfs/scrub.c:2706
 btrfs_scrub_dev+0x774/0xde0 fs/btrfs/scrub.c:3028
 btrfs_ioctl_scrub+0x236/0x370 fs/btrfs/ioctl.c:3251
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e99a28f19
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcb799b9b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4e99a28f19
RDX: 0000000020000000 RSI: 00000000c400941b RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcb799ba00
R13: 00007ffcb799bc88 R14: 431bde82d7b634db R15: 00007f4e99a7103b
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_lookup_csums_bitmap+0xc4/0x1600 fs/btrfs/file-item.c:615
Code: 8c 24 a8 00 00 00 42 c7 44 31 08 f3 f3 f3 f3 e8 d2 83 e1 fd 48 89 9c 24 88 00 00 00 48 81 c3 08 02 00 00 48 89 d8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 df e8 9d 39 4b fe 4c 8b 2b ba 11 00 00
RSP: 0018:ffffc9000af5f100 EFLAGS: 00010206
RAX: 0000000000000041 RBX: 0000000000000208 RCX: ffff888000cf2440
RDX: 0000000000000000 RSI: ffff888047132080 RDI: 0000000000000000
RBP: ffffc9000af5f290 R08: ffff88801fb3c800 R09: ffffc9000af5f420
R10: dffffc0000000000 R11: ffffed1008e2402e R12: 0000000000500000
R13: ffffc9000af5f420 R14: dffffc0000000000 R15: 0000000000500000
FS:  00005555764d5480(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055572fc64400 CR3: 0000000040a06000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	8c 24 a8             	mov    %fs,(%rax,%rbp,4)
   3:	00 00                	add    %al,(%rax)
   5:	00 42 c7             	add    %al,-0x39(%rdx)
   8:	44 31 08             	xor    %r9d,(%rax)
   b:	f3 f3 f3 f3 e8 d2 83 	repz repz repz repz call 0xfde183e6
  12:	e1 fd
  14:	48 89 9c 24 88 00 00 	mov    %rbx,0x88(%rsp)
  1b:	00
  1c:	48 81 c3 08 02 00 00 	add    $0x208,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 9d 39 4b fe       	call   0xfe4b39d6
  39:	4c 8b 2b             	mov    (%rbx),%r13
  3c:	ba                   	.byte 0xba
  3d:	11 00                	adc    %eax,(%rax)

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/19 10:25 upstream b04ae0f45168 cd6fc0a3 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root general protection fault in btrfs_lookup_csums_bitmap
2024/11/12 04:04 upstream 2d5404caa8c7 75bb1b32 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in btrfs_lookup_csums_bitmap
2024/10/19 08:58 upstream b04ae0f45168 cd6fc0a3 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in btrfs_lookup_csums_bitmap
* Struck through repros no longer work on HEAD.