btrfs: don't abort filesystem when attempting to snapshot deleted subvolume
If the source file descriptor to the snapshot ioctl refers to a deleted
subvolume, we get the following abort:
BTRFS: Transaction aborted (error -2)
WARNING: CPU: 0 PID: 833 at fs/btrfs/transaction.c:1875 create_pending_snapshot+0x1040/0x1190 [btrfs]
Modules linked in: pata_acpi btrfs ata_piix libata scsi_mod virtio_net blake2b_generic xor net_failover virtio_rng failover scsi_common rng_core raid6_pq libcrc32c
CPU: 0 PID: 833 Comm: t_snapshot_dele Not tainted 6.7.0-rc6 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014
RIP: 0010:create_pending_snapshot+0x1040/0x1190 [btrfs]
RSP: 0018:ffffa09c01337af8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff9982053e7c78 RCX: 0000000000000027
RDX: ffff99827dc20848 RSI: 0000000000000001 RDI: ffff99827dc20840
RBP: ffffa09c01337c00 R08: 0000000000000000 R09: ffffa09c01337998
R10: 0000000000000003 R11: ffffffffb96da248 R12: fffffffffffffffe
R13: ffff99820535bb28 R14: ffff99820b7bd000 R15: ffff99820381ea80
FS: 00007fe20aadabc0(0000) GS:ffff99827dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559a120b502f CR3: 00000000055b6000 CR4: 00000000000006f0
Call Trace:
<TASK>
? create_pending_snapshot+0x1040/0x1190 [btrfs]
? __warn+0x81/0x130
? create_pending_snapshot+0x1040/0x1190 [btrfs]
? report_bug+0x171/0x1a0
? handle_bug+0x3a/0x70
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? create_pending_snapshot+0x1040/0x1190 [btrfs]
? create_pending_snapshot+0x1040/0x1190 [btrfs]
create_pending_snapshots+0x92/0xc0 [btrfs]
btrfs_commit_transaction+0x66b/0xf40 [btrfs]
btrfs_mksubvol+0x301/0x4d0 [btrfs]
btrfs_mksnapshot+0x80/0xb0 [btrfs]
__btrfs_ioctl_snap_create+0x1c2/0x1d0 [btrfs]
btrfs_ioctl_snap_create_v2+0xc4/0x150 [btrfs]
btrfs_ioctl+0x8a6/0x2650 [btrfs]
? kmem_cache_free+0x22/0x340
? do_sys_openat2+0x97/0xe0
__x64_sys_ioctl+0x97/0xd0
do_syscall_64+0x46/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
RIP: 0033:0x7fe20abe83af
RSP: 002b:00007ffe6eff1360 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fe20abe83af
RDX: 00007ffe6eff23c0 RSI: 0000000050009417 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 00007fe20ad16cd0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe6eff13c0 R14: 00007fe20ad45000 R15: 0000559a120b6d58
</TASK>
---[ end trace 0000000000000000 ]---
BTRFS: error (device vdc: state A) in create_pending_snapshot:1875: errno=-2 No such entry
BTRFS info (device vdc: state EA): forced readonly
BTRFS warning (device vdc: state EA): Skipping commit of aborted transaction.
BTRFS: error (device vdc: state EA) in cleanup_transaction:2055: errno=-2 No such entry
This happens because create_pending_snapshot() initializes the new root
item as a copy of the source root item. This includes the refs field,
which is 0 for a deleted subvolume. The call to btrfs_insert_root()
therefore inserts a root with refs == 0. btrfs_get_new_fs_root() then
finds the root and returns -ENOENT if refs == 0, which causes
create_pending_snapshot() to abort.
Fix it by checking the source root's refs before attempting the
snapshot, but after locking subvol_sem to avoid racing with deletion.
Analysis and contextual insights are available on OpenCVE Cloud.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-3842-1 | linux-5.10 security update |
Debian DSA |
DSA-5681-1 | linux security update |
Ubuntu USN |
USN-6766-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6766-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6766-3 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-6795-1 | Linux kernel (Intel IoTG) vulnerabilities |
Ubuntu USN |
USN-6818-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6818-2 | Linux kernel (ARM laptop) vulnerabilities |
Ubuntu USN |
USN-6818-3 | Linux kernel (NVIDIA) vulnerabilities |
Ubuntu USN |
USN-6818-4 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-6819-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6819-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-6819-3 | Linux kernel (OEM) vulnerabilities |
Ubuntu USN |
USN-6819-4 | Linux kernel (Oracle) vulnerabilities |
Ubuntu USN |
USN-6828-1 | Linux kernel (Intel IoTG) vulnerabilities |
Thu, 17 Jul 2025 17:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Mon, 17 Mar 2025 15:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Debian
Debian debian Linux Linux Linux linux Kernel |
|
| Weaknesses | CWE-908 | |
| CPEs | cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:* |
|
| Vendors & Products |
Debian
Debian debian Linux Linux Linux linux Kernel |
Fri, 22 Nov 2024 12:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Tue, 05 Nov 2024 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-05-11T20:01:23.654Z
Reserved: 2024-02-19T14:20:24.138Z
Link: CVE-2024-26644
Updated: 2024-08-02T00:07:19.716Z
Status : Modified
Published: 2024-03-26T16:15:12.137
Modified: 2025-07-17T17:15:33.783
Link: CVE-2024-26644
OpenCVE Enrichment
No data.
Debian DLA
Debian DSA
Ubuntu USN