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: 16d, last: 3d05h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
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 (1)
Title Replies (including bot) Last reply
[syzbot] [btrfs?] WARNING in btrfs_create_new_inode (3) 0 (1) 2026/08/10 00:12
Similar bugs (5)
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 361d 361d 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 1099d 1383d 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 616d 629d 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 403d 404d 0/2 auto-obsoleted due to no activity on 2025/10/21 20:33
upstream WARNING in btrfs_create_new_inode (2) btrfs -1 4 412d 530d 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:6751 at btrfs_create_new_inode+0x1ddc/0x1ee0 fs/btrfs/inode.c:6751, CPU#0: syz.0.0/5319
Modules linked in:
CPU: 0 UID: 0 PID: 5319 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+0x1ddc/0x1ee0 fs/btrfs/inode.c:6751
Code: 00 00 00 83 fb f4 0f 85 e8 00 00 00 e8 ed 13 b3 fd e9 e7 00 00 00 e8 e3 13 b3 fd eb 10 e8 dc 13 b3 fd eb 09 e8 d5 13 b3 fd 90 <0f> 0b 90 89 d9 f7 d9 e9 b8 f8 ff ff e8 c3 13 b3 fd eb 10 e8 bc 13
RSP: 0018:ffffc9000ec07a00 EFLAGS: 00010287
RAX: ffffffff8413ff4b RBX: 00000000ffffffe4 RCX: 0000000000100000
RDX: ffffc90020001000 RSI: 0000000000002ced RDI: 0000000000002cee
RBP: ffffc9000ec07c30 R08: ffff88803ec28000 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000002 R12: ffff8880131d87b8
R13: ffff8880441ec610 R14: 00000000ffffffe4 R15: ffff888050354001
FS:  00007f8cd68326c0(0000) GS:ffff88808c539000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000043b1c000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 btrfs_create_common+0x189/0x310 fs/btrfs/inode.c:6978
 vfs_create+0x2be/0x450 fs/namei.c:4197
 filename_mknodat+0x3e8/0x660 fs/namei.c:5319
 __do_sys_mknod fs/namei.c:5356 [inline]
 __se_sys_mknod+0x3a/0x150 fs/namei.c:5353
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8cd599e0d9
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:00007f8cd6831fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f8cd5c26090 RCX: 00007f8cd599e0d9
RDX: 0000000000000701 RSI: 00000000000000c0 RDI: 0000200000000000
RBP: 00007f8cd5a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8cd5c26128 R14: 00007f8cd5c26090 R15: 00007ffe569e7178
 </TASK>

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.