syzbot


kernel BUG in bch2_trans_update_by_path (2)

Status: upstream: reported C repro on 2025/09/12 07:06
Subsystems: bcachefs
[Documentation on labels]
Reported-by: syzbot+e7b9dfa79acffd3aabdd@syzkaller.appspotmail.com
First crash: 47d, last: 14d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bcachefs?] kernel BUG in bch2_trans_update_by_path (2) 0 (2) 2025/09/25 10:26
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG in bch2_trans_update_by_path bcachefs -1 C done 857 56d 131d 29/29 fixed on 2025/09/04 16:57
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/10/14 12:28 20m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log

Sample crash report:
bcachefs (loop0): pointer to missing indirect extent in (disconnected) offset 0: -12288
  u64s 7 type reflink_p 4102:24:U32_MAX len 24 ver 0: idx 0 front_pad 0 back_pad 0
  missing reflink btree range 0-24, fixing
------------[ cut here ]------------
kernel BUG at fs/bcachefs/btree_update.c:410!
Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6643 Comm: syz-executor Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : bch2_trans_update_by_path+0x17ec/0x17f0 fs/bcachefs/btree_update.c:410
lr : bch2_trans_update_by_path+0x17ec/0x17f0 fs/bcachefs/btree_update.c:410
sp : ffff8000a10661c0
x29: ffff8000a1066380 x28: 0000000000000004 x27: ffff0000c83cc000
x26: 0000000000000000 x25: ffff0000d6c81268 x24: 1fffe00019079802
x23: 0000000000000000 x22: ffff0000c83ce4d8 x21: 0000000000004000
x20: dfff800000000000 x19: ffff0000c83ce4d8 x18: 00000000ffffffff
x17: 3233553a303a3230 x16: ffff80008af86288 x15: 0000000000000003
x14: 0000000000000000 x13: 0000000000000006 x12: 0000000000ff0100
x11: ffff0000d33bbd00 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000d33bbd00 x7 : 0000100600000000 x6 : ffff800082901c6c
x5 : 0000000000000812 x4 : ffff8000828fcb24 x3 : 0000000000100000
x2 : ffff0000d6c81268 x1 : 0000000000004000 x0 : 0000000000000000
Call trace:
 bch2_trans_update_by_path+0x17ec/0x17f0 fs/bcachefs/btree_update.c:410 (P)
 bch2_trans_update_ip+0x7bc/0x17ec fs/bcachefs/btree_update.c:531
 bch2_trans_update+0x4c/0x60 fs/bcachefs/btree_update.h:123
 bch2_btree_insert_nonextent fs/bcachefs/btree_update.c:625 [inline]
 bch2_trans_update_extent fs/bcachefs/btree_update.c:321 [inline]
 bch2_trans_update_ip+0x1320/0x17ec fs/bcachefs/btree_update.c:503
 bch2_trans_update+0x4c/0x60 fs/bcachefs/btree_update.h:123
 bch2_btree_insert_trans+0x180/0x2a8 fs/bcachefs/btree_update.c:637
 bch2_indirect_extent_missing_error+0x778/0xafc fs/bcachefs/reflink.c:239
 bch2_lookup_indirect_extent+0x334/0x558 fs/bcachefs/reflink.c:279
 trans_trigger_reflink_p_segment fs/bcachefs/reflink.c:308 [inline]
 __trigger_reflink_p+0x270/0xf40 fs/bcachefs/reflink.c:419
 bch2_trigger_reflink_p+0x114/0x244 fs/bcachefs/reflink.c:454
 run_one_trans_trigger fs/bcachefs/btree_trans_commit.c:-1 [inline]
 bch2_trans_commit_run_triggers fs/bcachefs/btree_trans_commit.c:554 [inline]
 __bch2_trans_commit+0x800/0x625c fs/bcachefs/btree_trans_commit.c:1023
 bch2_trans_commit fs/bcachefs/btree_update.h:241 [inline]
 bch2_inode_delete_keys+0x3d8/0x584 fs/bcachefs/inode.c:1115
 bch2_inode_rm+0x214/0x4e0 fs/bcachefs/inode.c:1146
 bch2_evict_inode+0x1b4/0x444 fs/bcachefs/fs.c:2182
 evict+0x414/0x928 fs/inode.c:810
 iput_final fs/inode.c:1897 [inline]
 iput+0x6e4/0x83c fs/inode.c:1923
 do_unlinkat+0x300/0x488 fs/namei.c:4657
 __do_sys_unlinkat fs/namei.c:4691 [inline]
 __se_sys_unlinkat fs/namei.c:4684 [inline]
 __arm64_sys_unlinkat+0xdc/0xf8 fs/namei.c:4684
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:763
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
Code: d4210000 9778c3b9 d4210000 9778c3b7 (d4210000) 
---[ end trace 0000000000000000 ]---

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/25 10:25 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 0f3be52b8e37 0abd0691 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 kernel BUG in bch2_trans_update_by_path
2025/09/30 05:18 upstream 449c2b302c8e 86341da6 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in bch2_trans_update_by_path
2025/09/18 04:22 upstream d4b779985a6c e2beed91 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in bch2_trans_update_by_path
2025/09/12 03:14 upstream 02ffd6f89c50 e2beed91 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in bch2_trans_update_by_path
2025/09/11 22:16 upstream 02ffd6f89c50 e2beed91 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in bch2_trans_update_by_path
2025/09/26 02:37 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 35aa5763e111 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 kernel BUG in bch2_trans_update_by_path
2025/09/25 09:24 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 0f3be52b8e37 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 kernel BUG in bch2_trans_update_by_path
* Struck through repros no longer work on HEAD.