CVE-2021-47040

io_uring: fix overflows checks in provide buffers

HIGH
7.8
CVSS Score
Published: February 28, 2024 at 08:13 AM UTC
Updated: August 5, 2026 at 09:24 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix overflows checks in provide buffers Colin reported before possible overflow and sign extension problems in io_provide_buffers_prep(). As Linus pointed out previous attempt did nothing useful, see d81269fecb8ce ("io_uring: fix provide_buffers sign extension"). Do that with help of check_<op>_overflow helpers. And fix struct io_provide_buf::len type, as it doesn't make much sense to keep it signed.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.11 ≤ v < 5.11.215.12 ≤ v < 5.12.45.8 ≤ v < 5.10.375.8 ≤ v < 5.11.215.8 ≤ v < 5.12.45.8 ≤ v < 5.135.8efe68c1ca8f49e8c06afd74b699411bfbb8ba1ff
Vendor states this is fixed in 38134ada0ceea3e848fe993263c0ff6207fd46e7 (fixed)
Vendor states this is fixed in 51bf90901952aaac564bbdb36b2b503050c53dd9 (fixed)
Vendor states this is fixed in 84b8c266c4bfe9ed5128e13253c388deb74b1b03 (fixed)
Vendor states this is fixed in cbbc13b115b8f18e0a714d89f87fbdc499acfe2d (fixed)
Vendor states this is fixed in 5.10.37 (unaffected)
Vendor states this is fixed in 5.11.21 (unaffected)
Vendor states this is fixed in 5.12.4 (unaffected)
Vendor states this is fixed in 5.13 (unaffected)
Vendor states this is fixed in 5.8 (unaffected)

References (4)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/38134ada0ceea3e848fe993263c0ff6207fd46e7
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/51bf90901952aaac564bbdb36b2b503050c53dd9
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/84b8c266c4bfe9ed5128e13253c388deb74b1b03
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/cbbc13b115b8f18e0a714d89f87fbdc499acfe2d

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-120

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