Bug 2347778 (CVE-2022-49112)

Summary:	CVE-2022-49112 kernel: mt76: fix monitor mode crash with sdio driver
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	dfreiber, drow, jburrell, vkumar
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
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Description OSIDB Bzimport 2025-02-26 03:06:24 UTC

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

mt76: fix monitor mode crash with sdio driver

mt7921s driver may receive frames with fragment buffers. If there is a
CTS packet received in monitor mode, the payload is 10 bytes only and
need 6 bytes header padding after RXD buffer. However, only RXD in the
first linear buffer, if we pull buffer size RXD-size+6 bytes with
skb_pull(), that would trigger "BUG_ON(skb->len < skb->data_len)" in
__skb_pull().

To avoid the nonlinear buffer issue, enlarge the RXD size from 128 to
256 to make sure all MCU operation in linear buffer.

[   52.007562] kernel BUG at include/linux/skbuff.h:2313!
[   52.007578] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[   52.007987] pc : skb_pull+0x48/0x4c
[   52.008015] lr : mt7921_queue_rx_skb+0x494/0x890 [mt7921_common]
[   52.008361] Call trace:
[   52.008377]  skb_pull+0x48/0x4c
[   52.008400]  mt76s_net_worker+0x134/0x1b0 [mt76_sdio 35339a92c6eb7d4bbcc806a1d22f56365565135c]
[   52.008431]  __mt76_worker_fn+0xe8/0x170 [mt76 ef716597d11a77150bc07e3fdd68eeb0f9b56917]
[   52.008449]  kthread+0x148/0x3ac
[   52.008466]  ret_from_fork+0x10/0x30

Comment 1 Avinash Hanwate 2025-02-26 22:03:48 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025022602-CVE-2022-49112-3f57@gregkh/T