CVE-2026-93824: tls: reject the combination of TLS and sockmap
In the Linux kernel, the following vulnerability has been resolved:
tls: reject the combination of TLS and sockmap
TLS and sockmap (BPF psock) integration hides a lot of latent bugs. Bugs which may be more or less relevant for real users but they are definitely exploitable.
We could not find anyone actively using this integration so let's reject this config. Adding a TLS socket to a sockmap was already rejected by skpsockinit() through the inetcskhasulp() check. We need to reject the attempts to configure the TLS keys (rather than adding the ULP itself) because checking prior to the ULP installation is tricky without risking a race with sockmap getting added in parallel (sockmap does not hold the socket lock).
This patch is a minimal rejection of the feature. Subsequent patch in the series will do a light dead code removal. Full cleanup would require a major rewrite of the Tx path, we don't need skmsg any more.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.158.1-1 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.190-1Fixed in 6.12.115-2Fixed in 7.2.12-1Fixed in 7.2.15-1 - Upgrade
Upgrade
debian/linux-6.12to a version that resolves this vulnerability.Fixed in 6.12.113-1~deb12u1 - Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42~24.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1~24.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-42.42 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1016.17 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1016.18 - Upgrade
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ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1015.16 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1 - Configuration
Reject or do not configure TLS sockets and TLS keys for use with sockmap (BPF psock).
TLS and sockmap (BPF psock) integration TLS and sockmap combination = rejected
Event History
Frequently Asked Questions
Who is realistically exposed to this issue?
Exposure is limited to systems that combine kernel TLS with sockmap/BPF psock integration. The provided information states that no active users of this integration were found.
What attacker capability is needed to exploit it?
An attacker would need to be able to cause TLS keys to be configured on a socket while it is associated with sockmap, or otherwise exercise the TLS-and-sockmap combination. The issue concerns latent bugs in that integration rather than ordinary TLS use alone.
Are default Linux TLS configurations affected?
The vulnerability data only identifies the combination of TLS and sockmap as affected. It does not indicate that TLS without sockmap, or a default configuration that does not use this integration, is affected.
What is the mitigation if the kernel fix cannot be deployed immediately?
Avoid using TLS sockets with sockmap/BPF psock integration, including configuring TLS keys for sockets that may be added to sockmap. The resolution described rejects this configuration.