block: don't revert iter for -EIOCBQUEUED
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: block: don't revert iter for -EIOCBQUEUED blkdev_read_iter() has a few odd checks, like gating the position and count adjustment on whether or not the result is bigger-than-or-equal to zero (where bigger than makes more sense), and not checking the return value of blkdev_direct_IO() before doing an iov_iter_revert(). The latter can lead to attempting to revert with a negative value, which when passed to iov_iter_revert() as an unsigned value will lead to throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT. Be sane and don't revert for -EIOCBQUEUED, like what is done in other spots.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.17 and later | 6.1.129, 6.6.78, 6.12.14, 6.13.3, 6.14 | Patch available | CNA |
- Linux VendorLinux Affected 5.17 and later Fixed in 6.1.129, 6.6.78, 6.12.14, 6.13.3, 6.14 Patch available CNA
CPE configurations NVD · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.17.1 to before 6.1.129; 6.2 to before 6.6.78; 6.7 to before 6.12.14; 6.13 to before 6.13.3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:-:*:*:*:*:*:* | 5.17 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:rc3:*:*:*:*:*:* | 5.17 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:rc4:*:*:*:*:*:* | 5.17 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:rc5:*:*:*:*:*:* | 5.17 rc5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:rc6:*:*:*:*:*:* | 5.17 rc6 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:rc7:*:*:*:*:*:* | 5.17 rc7 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.17:rc8:*:*:*:*:*:* | 5.17 rc8 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.17.1 to before 6.1.129; 6.2 to before 6.6.78; 6.7 to before 6.12.14; 6.13 to before 6.13.3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:-:*:*:*:*:*:* Versions 5.17 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:rc3:*:*:*:*:*:* Versions 5.17 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:rc4:*:*:*:*:*:* Versions 5.17 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:rc5:*:*:*:*:*:* Versions 5.17 rc5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:rc6:*:*:*:*:*:* Versions 5.17 rc6 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:rc7:*:*:*:*:*:* Versions 5.17 rc7 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.17:rc8:*:*:*:*:*:* Versions 5.17 rc8 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.1.129, 6.6.78, 6.12.14, 6.13.3, 6.14
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2025-21832
- 2026-10-03 Alias added: GHSA-cwfx-m26m-rjc8
- 2026-10-16 CISA SSVC decision points changed
References
Patch 5
- https://git.kernel.org/stable/c/6c26619effb1b4cb7d20b4e666ab8f71f6a53ccb
- https://git.kernel.org/stable/c/84671b0630ccb46ae9f1f99a45c7d63ffcd6a474
- https://git.kernel.org/stable/c/68f16d3034a06661245ecd22f0d586a8b4e7c473
- https://git.kernel.org/stable/c/a58f136bad29f9ae721a29d98c042fddbee22f77
- https://git.kernel.org/stable/c/b13ee668e8280ca5b07f8ce2846b9957a8a10853
More Linux Kernel vulnerabilities
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- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2025-21832 · CVE Program
- CVE-2025-21832 · NVD
- FIRST EPSS
- GHSA-cwfx-m26m-rjc8 · GitHub Advisory Database · CC BY 4.0
- CVE-2025-21832 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences