Linux CVE-2026-90398

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

wifi: ath11k: fix stride mismatch in mac_phy_caps_parse()

Currently, in ath11k_wmi_tlv_mac_phy_caps_parse(), kcalloc() sizes the mac_phy_caps buffer as tot_phy_id * len, where len is clamped to min(firmware_len, sizeof(struct wmi_mac_phy_capabilities)). The subsequent memcpy() destination advances by sizeof(full struct) per slot via C pointer arithmetic, not by the clamped len. When firmware sends short TLVs, the second and later slots are written past the end of the allocation.

The reader in ath11k_pull_mac_phy_cap_svc_ready_ext() also indexes the buffer with full-struct pointer arithmetic, so the allocation must match that stride.

Fix by using kzalloc_objs(), which derives the element size from the pointer type, making allocation size and pointer stride provably consistent regardless of what len the firmware provides.

Compile tested only.