WARNING in btrfs_create_new_inode (3)

Status: upstream: reported on 2026/08/10 00:12
Subsystems: btrfs
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+c1b8c52e6c0142c5e448@syzkaller.appspotmail.com
First crash: 97d, last: 9h31m
▶ ▼ ✨ AI Jobs (3)
ID Workflow Result Correct Bug Created Started Finished Revision
1885b573 repro-c 💥 WARNING in btrfs_create_new_inode (3) 2026/10/05 08:34 2026/10/05 08:34 2026/10/05 12:21 57bbd979
edc16be1 repro-c 💥 WARNING in btrfs_create_new_inode (3) 2026/10/03 16:25 2026/10/03 16:25 2026/10/03 23:12 57bbd979
d615a2d1 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ WARNING in btrfs_create_new_inode (3) 2026/08/09 09:11 2026/08/09 09:11 2026/08/09 09:58 5d63f80b
▶ ▼ Discussions (2)
Title Replies (including bot) Last reply
[syzbot] Monthly btrfs report (Sep 2026) 0 (1) 2026/09/04 20:33
[syzbot] [btrfs?] WARNING in btrfs_create_new_inode (3) 0 (1) 2026/08/10 00:12
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in btrfs_create_new_inode (2) -1 1 442d 442d 0/3 auto-obsoleted due to no activity on 2025/12/02 17:31
upstream WARNING in btrfs_create_new_inode btrfs -1 syz, C 5 1179d 1464d 0/29 auto-obsoleted due to no activity on 2023/11/26 02:10
linux-6.1 WARNING in btrfs_create_new_inode -1 2 697d 710d 0/3 auto-obsoleted due to no activity on 2025/03/22 10:24
linux-6.6 WARNING in btrfs_create_new_inode -1 2 484d 485d 0/2 auto-obsoleted due to no activity on 2025/10/21 20:33
linux-6.1 WARNING in btrfs_create_new_inode (3) origin:upstream -1 syz, C 3 43d 43d 0/3 upstream: reported C repro on 2026/09/27 06:04
upstream WARNING in btrfs_create_new_inode (2) btrfs -1 4 493d 611d 0/29 auto-obsoleted due to no activity on 2025/10/12 16:42

Sample crash report:
------------[ cut here ]------------
btrfs_abort_should_print_stack(__error)
WARNING: fs/btrfs/inode.c:6710 at btrfs_create_new_inode+0x1eec/0x2030 fs/btrfs/inode.c:6710, CPU#0: syz.0.0/5350
Modules linked in:
CPU: 0 UID: 0 PID: 5350 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:btrfs_create_new_inode+0x1eec/0x2030 fs/btrfs/inode.c:6710
Code: 00 00 00 83 fb f4 0f 85 fc 00 00 00 e8 1d 59 9d fd e9 fb 00 00 00 e8 13 59 9d fd eb 10 e8 0c 59 9d fd eb 09 e8 05 59 9d fd 90 <0f> 0b 90 89 d9 f7 d9 e9 c8 f8 ff ff e8 f3 58 9d fd eb 10 e8 ec 58
RSP: 0018:ffffc9000de2f9a0 EFLAGS: 00010283
RAX: ffffffff842bd92b RBX: 00000000ffffffe4 RCX: 0000000000100000
RDX: ffffc90020001000 RSI: 00000000000010ca RDI: 00000000000010cb
RBP: ffffc9000de2fbd0 R08: ffff88800fc82580 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000002 R12: ffff8880459f87b8
R13: ffff888045a3c610 R14: 00000000ffffffe4 R15: ffff888051b7c001
FS:  00007f70113d46c0(0000) GS:ffff88808a9f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70113d3ff8 CR3: 000000000fc99000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 btrfs_create_common+0x189/0x310 fs/btrfs/inode.c:6960
 btrfs_mkdir+0xc1/0xf0 fs/btrfs/inode.c:7099
 vfs_mkdir+0x411/0x660 fs/namei.c:5428
 filename_mkdirat+0x284/0x550 fs/namei.c:5461
 __do_sys_mkdirat fs/namei.c:5482 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5479
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x16a/0x530 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7014f9fb19
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f70113d3fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f7015226090 RCX: 00007f7014f9fb19
RDX: 00000000000001ff RSI: 0000200000000500 RDI: ffffffffffffff9c
RBP: 00007f7015037b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7015226128 R14: 00007f7015226090 R15: 00007ffea1c54878
 </TASK>

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/11/09 15:00 upstream 7475ea8b5861 5cecaf1f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/11/09 04:14 upstream 8a65162514fb 5cecaf1f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/27 01:07 upstream 6812ce4e4379 a3c7249d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/18 08:22 upstream 4982d3552a3b 8d7d05f1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/08 07:25 upstream 28924df2a08f 680aa3e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/03 04:06 upstream 940de590b839 6a988719 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/03 04:02 upstream 940de590b839 6a988719 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/03 04:00 upstream 940de590b839 6a988719 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/09/03 03:56 upstream 940de590b839 6a988719 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/25 16:35 upstream 818bebeb63dd a9a1fc32 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/18 04:19 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/18 04:18 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/18 04:11 upstream ff68e5f557f6 1e72964b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/12 13:43 upstream f5bbbfec59b4 ee03bfea .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/12 06:57 upstream f5bbbfec59b4 f8d35649 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/12 06:56 upstream f5bbbfec59b4 f8d35649 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/12 06:51 upstream f5bbbfec59b4 f8d35649 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
2026/08/04 14:13 upstream 848acc8ffe1b 3c5eaa21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in btrfs_create_new_inode
* Struck through repros no longer work on HEAD.