PT-2026-30177 · Linux · Linux

Published 2026-04-03 · Updated 2026-04-03 · CVE-2026-31394

Mitre

In the Linux kernel, the following vulnerability has been resolved:

mac80211: fix crash in ieee80211 chan bw change for AP VLAN stations

ieee80211 chan bw change() iterates all stations and accesses link->reserved.oper via sta->sdata->link[link id]. For stations on AP VLAN interfaces (e.g. 4addr WDS clients), sta->sdata points to the VLAN sdata, whose link never participates in chanctx reservations. This leaves link->reserved.oper zero-initialized with chan == NULL, causing a NULL pointer dereference in ieee80211 sta cap rx bw() when accessing chandef->chan->band during CSA.

Resolve the VLAN sdata to its parent AP sdata using get bss sdata() before accessing link data.

[also change sta->sdata in ARRAY SIZE even if it doesn't matter]

Related Identifiers

CVE-2026-31394

Affected Products

Linux

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-31394 · Security Note
• https://git.kernel.org/stable/c/5a86d4e920d9783a198e39cf53f0e410fba5fbd6 · Note
• https://git.kernel.org/stable/c/3c6629e859a2211a1fbb4868f915413f80001ca5 · Note
• https://git.kernel.org/stable/c/65c25b588994dd422fea73fa322de56e1ae4a33b · Note
• https://git.kernel.org/stable/c/672e5229e1ecfc2a3509b53adcb914d8b024a853 · Note