syzbot


kernel BUG in scrub_stripe_get_kaddr

Status: upstream: reported C repro on 2025/09/29 19:45
Subsystems: btrfs
[Documentation on labels]
Reported-by: syzbot+bde59221318c592e6346@syzkaller.appspotmail.com
First crash: 1d13h, last: 1d12h
Cause bisection: failed (error log, bisect log)
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [btrfs?] kernel BUG in scrub_stripe_get_kaddr 1 (2) 2025/09/29 22:14

Sample crash report:
BTRFS info (device loop0): force clearing of disk cache
BTRFS info (device loop0): enabling auto defrag
BTRFS info (device loop0): max_inline set to 0
BTRFS info (device loop0): scrub: started on devid 1
assertion failed: !folio_test_partial_kmap(folio) :: 0, in fs/btrfs/scrub.c:697
------------[ cut here ]------------
kernel BUG at fs/btrfs/scrub.c:697!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6077 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:scrub_stripe_get_kaddr+0x1bb/0x1c0 fs/btrfs/scrub.c:697
Code: 0f 0b e8 b8 14 db fd 48 c7 c7 60 8d ef 8b 48 c7 c6 a0 9f ef 8b 31 d2 48 c7 c1 20 8e ef 8b 41 b8 b9 02 00 00 e8 86 58 42 fd 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc9000354f0d0 EFLAGS: 00010246
RAX: 000000000000004f RBX: ffff88805bfa0010 RCX: f481606445f80d00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 000000000000000c R08: ffffc9000354ede7 R09: 1ffff920006a9dbc
R10: dffffc0000000000 R11: fffff520006a9dbd R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff88805bfa0010 R15: 000000000000000c
FS:  000055556411a500(0000) GS:ffff8881259fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f34bfdf2b60 CR3: 000000007537c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 scrub_bio_add_sector fs/btrfs/scrub.c:932 [inline]
 scrub_submit_initial_read+0xf21/0x1120 fs/btrfs/scrub.c:1897
 submit_initial_group_read+0x423/0x5b0 fs/btrfs/scrub.c:1952
 flush_scrub_stripes+0x18f/0x1150 fs/btrfs/scrub.c:1973
 scrub_stripe+0xbea/0x2a30 fs/btrfs/scrub.c:2516
 scrub_chunk+0x2a3/0x430 fs/btrfs/scrub.c:2575
 scrub_enumerate_chunks+0xa70/0x1350 fs/btrfs/scrub.c:2839
 btrfs_scrub_dev+0x6e7/0x10e0 fs/btrfs/scrub.c:3153
 btrfs_ioctl_scrub+0x249/0x4b0 fs/btrfs/ioctl.c:3163
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2f5d78eec9
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:00007ffef70163e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2f5d9e5fa0 RCX: 00007f2f5d78eec9
RDX: 0000200000000000 RSI: 00000000c400941b RDI: 0000000000000004
RBP: 00007f2f5d811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2f5d9e5fa0 R14: 00007f2f5d9e5fa0 R15: 0000000000000003
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:scrub_stripe_get_kaddr+0x1bb/0x1c0 fs/btrfs/scrub.c:697
Code: 0f 0b e8 b8 14 db fd 48 c7 c7 60 8d ef 8b 48 c7 c6 a0 9f ef 8b 31 d2 48 c7 c1 20 8e ef 8b 41 b8 b9 02 00 00 e8 86 58 42 fd 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc9000354f0d0 EFLAGS: 00010246
RAX: 000000000000004f RBX: ffff88805bfa0010 RCX: f481606445f80d00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 000000000000000c R08: ffffc9000354ede7 R09: 1ffff920006a9dbc
R10: dffffc0000000000 R11: fffff520006a9dbd R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff88805bfa0010 R15: 000000000000000c
FS:  000055556411a500(0000) GS:ffff888125afc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556796dbd950 CR3: 000000007537c000 CR4: 00000000003526f0

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/28 20:38 linux-next 262858079afd 001c9061 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci-upstream-linux-next-kasan-gce-root kernel BUG in scrub_stripe_get_kaddr
2025/09/28 20:13 linux-next 262858079afd 001c9061 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci-upstream-linux-next-kasan-gce-root kernel BUG in scrub_stripe_get_kaddr
2025/09/28 19:50 linux-next 262858079afd 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root kernel BUG in scrub_stripe_get_kaddr
2025/09/28 19:48 linux-next 262858079afd 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root kernel BUG in scrub_stripe_get_kaddr
* Struck through repros no longer work on HEAD.