btrfs: fix double accounting race when btrfs_run_delalloc_range() failed
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix double accounting race when btrfs_run_delalloc_range() failed [BUG] When running btrfs with block size (4K) smaller than page size (64K, aarch64), there is a very high chance to crash the kernel at generic/750, with the following messages: (before the call traces, there are 3 extra debug messages added) BTRFS warning (device dm-3): read-write for sector size 4096 with page size 65536 is experimental BTRFS info (device dm-3): checking UUID tree hrtimer: interrupt took 5451385 ns BTRFS error (device dm-3): cow_file_range failed, root=4957 inode=257 start=1605632 len=69632: -28 BTRFS error (device dm-3): run_delalloc_nocow failed, root=4957 inode=257 start=1605632 len=69632: -28 BTRFS error (device dm-3): failed to run delalloc range, root=4957 ino=257 folio=1572864 submit_bitmap=8-15 start=1605632 len=69632: -28 ------------[ cut here ]------------ WARNING: CPU: 2 PID: 3020984 at ordered-data.c:360 can_finish_ordered_extent+0x370/0x3b8 [btrfs] CPU: 2 UID: 0 PID: 3020984 Comm: kworker/u24:1 Tainted: G OE 6.13.0-rc1-custom+ #89 Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs] pc : can_finish_ordered_extent+0x370/0x3b8 [btrfs] lr : can_finish_ordered_extent+0x1ec/0x3b8 [btrfs] Call trace: can_finish_ordered_extent+0x370/0x3b8 [btrfs] (P) can_finish_ordered_extent+0x1ec/0x3b8 [btrfs] (L) btrfs_mark_ordered_io_finished+0x130/0x2b8 [btrfs] extent_writepage+0x10c/0x3b8 [btrfs] extent_write_cache_pages+0x21c/0x4e8 [btrfs] btrfs_writepages+0x94/0x160 [btrfs] do_writepages+0x74/0x190 filemap_fdatawrite_wbc+0x74/0xa0 start_delalloc_inodes+0x17c/0x3b0 [btrfs] btrfs_start_delalloc_roots+0x17c/0x288 [btrfs] shrink_delalloc+0x11c/0x280 [btrfs] flush_space+0x288/0x328 [btrfs] btrfs_async_reclaim_data_space+0x180/0x228 [btrfs] process_one_work+0x228/0x680 worker_thread+0x1bc/0x360 kthread+0x100/0x118 ret_from_fork+0x10/0x20 ---[ end trace 0000000000000000 ]--- BTRFS critical (device dm-3): bad ordered extent accounting, root=4957 ino=257 OE offset=1605632 OE len=16384 to_dec=16384 left=0 BTRFS critical (device dm-3): bad ordered extent accounting, root=4957 ino=257 OE offset=1622016 OE len=12288 to_dec=12288 left=0 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 BTRFS critical (device dm-3): bad ordered extent accounting, root=4957 ino=257 OE offset=1634304 OE len=8192 to_dec=4096 left=0 CPU: 1 UID: 0 PID: 3286940 Comm: kworker/u24:3 Tainted: G W OE 6.13.0-rc1-custom+ #89 Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: btrfs_work_helper [btrfs] (btrfs-endio-write) pstate: 404000c5 (nZcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : process_one_work+0x110/0x680 lr : worker_thread+0x1bc/0x360 Call trace: process_one_work+0x110/0x680 (P) worker_thread+0x1bc/0x360 (L) worker_thread+0x1bc/0x360 kthread+0x100/0x118 ret_from_fork+0x10/0x20 Code: f84086a1 f9000fe1 53041c21 b9003361 (f9400661) ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Oops: Fatal exception SMP: stopping secondary CPUs SMP: failed to stop secondary CPUs 2-3 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: 0x275bb9540000 from 0xffff800080000000 PHYS_OFFSET: 0xffff8fbba0000000 CPU features: 0x100,00000070,00801250,8201720b [CAUSE] The above warning is triggered immediately after the delalloc range failure, this happens in the following sequence: - Range [1568K, 1636K) is dirty 1536K 1568K 1600K 1636K 1664K | |/////////|////////| | Where 1536K, 1600K and 1664K are page boundaries (64K page size) - Enter extent_writepage() for page 1536K - Enter run_delalloc_nocow() with locke ---truncated---
- Published
- Mar 12, 2025
- Updated
- Aug 5, 2026
- EPSS
- 0.2% · 12th percentile
- CWE
- CWE-770
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Report tools
Action score
22
Monitor
Low priority for now.
- CVSS
- 22 / 40 · 5.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 5.5
- CNA · Linux
- 7.8
- 2.3 point gap
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel5.0 and later · before 6.12.17
- linux linux kernel6.13 and later · before 6.13.5
- linux linux kernel4.19.73
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- eb124aaa2e85e9dceac37be5b7166a04b9b26735, 5.0affected
- d1051d6ebf8ef3517a5a3cf82bba8436d190f1c2 and later · before 21333148b5c9e52f41fafcedec3810b56a5e0e40affected · git
- d1051d6ebf8ef3517a5a3cf82bba8436d190f1c2 and later · before 0283ee1912c8e243c931f4ee5b3672e954fe0384affected · git
- d1051d6ebf8ef3517a5a3cf82bba8436d190f1c2 and later · before 72dad8e377afa50435940adfb697e070d3556670affected · git
- 4.19.73 and later · before 4.20affected · semver
- before 5.0not affected · semver
- 6.12.17 and later · up to and including 6.12.*not affected · semver
- 6.13.5 and later · up to and including 6.13.*not affected · semver
- 6.14 and laternot affected · original_commit_for_fix
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | all versions | — |
| Debian:13 | linux | before 6.12.17-1 | 6.12.17-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
- CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV83Now
- CVE-2019-13272In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to creKEV77This week
- CVE-2013-6282The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the v6k and v7 ARM platforms do not validate certain addKEV77This week
- CVE-2013-2094The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, which allows loKEV77This week
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 0283ee1912c8e243c931f4ee5b3672e954fe0384 | Vendor (CNA) |
| Linux Linux | 21333148b5c9e52f41fafcedec3810b56a5e0e40 | Vendor (CNA) |
| Linux Linux | 4.20 | Vendor (CNA) |
| Linux Linux | 72dad8e377afa50435940adfb697e070d3556670 | Vendor (CNA) |
| debian:linux | 6.12.17-1 · Debian:13 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2021-47137352 days apartnet: lantiq: fix memory corruption in RX ring39Monitor
- CVE-2024-35969296 days apartipv6: fix race condition between ipv6_get_ifaddr and ipv6_del_addr35Monitor
- CVE-2024-34027261 days apartf2fs: compress: fix to cover {reserve,release}_compress_blocks() w/ cp_rwsem lock31Monitor
- CVE-2021-47551292 days apartdrm/amd/amdkfd: Fix kernel panic when reset failed and been triggered again31Monitor
- CVE-2026-43329422 days apartnetfilter: flowtable: strictly check for maximum number of actions31Monitor
- CVE-2021-47130362 days apartnvmet: fix freeing unallocated p2pmem30Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-770 · Allocation of Resources Without Limits or ThrottlingCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- FloodingCAPEC-125likelihood: High · Medium
- Excessive AllocationCAPEC-130likelihood: Medium · Medium
- XML Ping of the DeathCAPEC-147likelihood: Low · Medium
- Exponential Data ExpansionCAPEC-197likelihood: High · Medium
- Serialized Data Parameter BlowupCAPEC-229likelihood: High · High
- Serialized Data with Nested PayloadsCAPEC-230likelihood: Medium · High
- Oversized Serialized Data PayloadsCAPEC-231likelihood: Medium · High
- HTTP DoSCAPEC-469Low
ATT&CK techniques
- Network Denial of Service:Direct Network FloodT1498.001
- Network Denial of Service:Reflection AmplificationT1498.002
- Endpoint Denial of ServiceT1499
- Endpoint Denial of Service: OS Exhaustion FloodT1499.001
- Endpoint Denial of Service:Service Exhaustion FloodT1499.002
- Endpoint Denial of Service:Application Exhaustion FloodT1499.003
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- git.kernel.org/stable/c/0283ee1912c8e243c931f4ee5b3672e954fe0384
- git.kernel.org/stable/c/21333148b5c9e52f41fafcedec3810b56a5e0e40
- git.kernel.org/stable/c/72dad8e377afa50435940adfb697e070d3556670
Vendor advisories and official records. Exploit/PoC links are deliberately left out.