Affected: Alpaquita:23: linux-lts, Alpaquita:25: linux-lts, Alpaquita:stream: linux-lts

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 cmd_node->data_buf. Several callers pass stack-allocated objects there.

If wait_event_interruptible_timeout() 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 cmd_node->data_buf 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:

cmd_wait_q terminated: -512 Unable to handle kernel paging request at virtual address 002c583837384662 Kernel panic - not syncing: stack-protector: Kernel stack is corrupted ... Tainted: [M]=MACHINE_CHECK

The fault address decodes as little-endian ASCII:

0x002c583837384662 -> "bF878X,\0"

which is a fragment of the VERSION_EXT 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 VERSION_EXT string. This points at a late VERSION_EXT response writing through a stale stack-backed data_buf after the interrupted wait returned.

After cancelling…

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 cmd_node->data_buf. Several callers pass stack-allocated objects there.

If wait_event_interruptible_timeout() 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 cmd_node->data_buf 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:

cmd_wait_q terminated: -512 Unable to handle kernel paging request at virtual address 002c583837384662 Kernel panic - not syncing: stack-protector: Kernel stack is corrupted ... Tainted: [M]=MACHINE_CHECK

The fault address decodes as little-endian ASCII:

0x002c583837384662 -> "bF878X,\0"

which is a fragment of the VERSION_EXT 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 VERSION_EXT string. This points at a late VERSION_EXT response writing through a stale stack-backed data_buf after the interrupted wait returned.

After cancelling…

kernel-devel-7.2.6-1.1 on GA media

Affected: Ubuntu:Pro:14.04:LTS: linux-aws, Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:14.04:LTS: linux-lts-xenial, Ubuntu:Pro:16.04:LTS: linux, Ubuntu:Pro:16.04:LTS: linux-aws, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe, Ubuntu:16.04:LTS: linux-hwe-edge and 245 more

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 cmd_node->data_buf. Several callers pass stack-allocated objects there. If wait_event_interruptible_timeout() 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 cmd_node->data_buf 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: cmd_wait_q terminated: -512 Unable to handle kernel paging request at virtual address 002c583837384662 Kernel panic - not syncing: stack-protector: Kernel stack is corrupted ... Tainted: [M]=MACHINE_CHECK The fault address decodes as little-endian ASCII: 0x002c583837384662 -> "bF878X,\0" which is a fragment of the VERSION_EXT 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 VERSION_EXT string. This points at a late VERSION_EXT response writing through a stale stack-backed data_buf after the interrupted wait returned. After cancelling pending comm…

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um Sicherheitsmaßnahmen zu umgehen, Daten oder den Systemzustand zu manipulieren, Denial-of-Service-Zustände herbeizuführen oder andere, nicht näher spezifizierte Angriffe durchzuführen.