CVE-2026-43502

net/rds: handle zerocopy send cleanup before the message is queued

HIGH
7.8
CVSS Score
Published: May 21, 2026 at 12:17 PM UTC
Updated: October 15, 2026 at 02:19 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.3%
SSVC
PoC

Description

In the Linux kernel, the following vulnerability has been resolved: net/rds: handle zerocopy send cleanup before the message is queued A zerocopy send can fail after user pages have been pinned but before the message is attached to the sending socket. The purge path currently infers zerocopy state from rm->m_rs, so an unqueued message can be cleaned up as if it owned normal payload pages. However, zerocopy ownership is really determined by the presence of op_mmp_znotifier, regardless of whether the message has reached the socket queue. Capture op_mmp_znotifier up front in rds_message_purge() and use it as the cleanup discriminator. If the message is already associated with a socket, keep the existing completion path. Otherwise, drop the pinned page accounting directly and release the notifier before putting the payload pages. This keeps early send failure cleanup consistent with the zerocopy lifetime rules without changing the normal queued completion path.

Affected

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

4.17 ≤ v < 5.10.2585.11 ≤ v < 5.15.2095.16 ≤ v < 6.1.1756.13 ≤ v < 6.18.306.19 ≤ v < 7.0.76.2 ≤ v < 6.6.1406.7 ≤ v < 6.12.880cebaccef3acbdfbc2d85880a2efb765d2f4e2e37.17.1 rc17.1 rc2
Vendor states this is fixed in 0f5c185fc79a59ee9991234dd6d2a3e5afa6e75b (fixed)
Vendor states this is fixed in 14ef6fd18db2494098b21e0471bf27a1d8e9993e (fixed)
Vendor states this is fixed in 1e262db7675e27f42c3f3f47d6011855f4454f24 (fixed)
Vendor states this is fixed in 21d70744e6d3bbf9293aa1ee6fba7c53ad75275e (fixed)
Vendor states this is fixed in 3abc8983b2bae3f487f77d9da5527d7d6b210d46 (fixed)
Vendor states this is fixed in 44b550d88b267320459d518c0743a241ab2108fa (fixed)
Vendor states this is fixed in 46662f7dc59475995609bf3e9d27eb36f4acf26f (fixed)
Vendor states this is fixed in e9aefdc5c53fe9aed108c14e3d155710a1bb14c9 (fixed)
Vendor states this is fixed in 4.17 (unaffected)
Vendor states this is fixed in 5.10.258 (unaffected)
Vendor states this is fixed in 5.15.209 (unaffected)
Vendor states this is fixed in 6.1.175 (unaffected)
Vendor states this is fixed in 6.12.88 (unaffected)
Vendor states this is fixed in 6.18.30 (unaffected)
Vendor states this is fixed in 6.6.140 (unaffected)
Vendor states this is fixed in 7.0.7 (unaffected)
Vendor states this is fixed in 7.1 (unaffected)

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

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

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusMODIFIED
CWE
NVD-CWE-noinfoCWE-401

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