UBUNTU-CVE-2026-80944: High severity ubuntu/linux-aws vulnerability

In the Linux kernel, the following vulnerability has been resolved: wifi: mwifiex: Detach sync cmd buffer on interrupted wait mwifiex synchronous commands keep the caller-provided data buffer in cmdnode->databuf. Several callers pass stack-allocated objects there. If waiteventinterruptibletimeout() is interrupted, the caller can return and release that stack object while the firmware command is still the current command. A late firmware response then reaches the normal response handler, which can copy data through cmdnode->databuf into the stale stack address. This fixes a stack corruption observed during repeated association and disassociation cycles. The panic trace showed the command wait being interrupted immediately before a bad pointer dereference: cmdwaitq terminated: -512 Unable to handle kernel paging request at virtual address 002c583837384662 Kernel panic - not syncing: stack-protector: Kernel stack is corrupted ... Tainted: [M]=MACHINECHECK The fault address decodes as little-endian ASCII: 0x002c583837384662 -> "bF878X,\0" which is a fragment of the VERSIONEXT firmware string exposed as debugfs "verext": w8997o-V4, RF878X, FP92, 16.92.21.p153.7 The same runs also showed corrupted control data containing: 0x2400372e333531 -> "153.7\0$" which is the tail of the same VERSIONEXT string. This points at a late VERSIONEXT response writing through a stale stack-backed databuf after the interrupted wait returned. After cancelling pending commands on an interrupted or timed-out wait, detach the caller-owned data buffer from the still-current command. This preserves the existing command cancellation behaviour while preventing a late response from writing through a pointer whose lifetime ended with the waiting caller. Tested on an i.MX8MP board using an 88W8997.