Bug 2482168 (CVE-2026-46027)

Summary: CVE-2026-46027 kernel: net/smc: avoid early lgr access in smc_clc_wait_msg
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's `net/smc` component. A remote attacker could exploit this by sending a Connection Less Connection (CLC) decline message during an early handshake stage. This causes the system to attempt to update link-group level synchronization state before it is properly initialized. This could lead to incorrect state management or unexpected system behavior.
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Description OSIDB Bzimport 2026-05-27 15:14:31 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net/smc: avoid early lgr access in smc_clc_wait_msg

A CLC decline can be received while the handshake is still in an early
stage, before the connection has been associated with a link group.

The decline handling in smc_clc_wait_msg() updates link-group level sync
state for first-contact declines, but that state only exists after link
group setup has completed. Guard the link-group update accordingly and
keep the per-socket peer diagnosis handling unchanged.

This preserves the existing sync_err handling for established link-group
contexts and avoids touching link-group state before it is available.
Comment 1 Keith Grant 2026-05-27 20:14:24 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052748-CVE-2026-46027-91a3@gregkh/T