Bug 2219270 (CVE-2023-4387)

Summary:	CVE-2023-4387 kernel: vmxnet3: use-after-free in vmxnet3_rq_alloc_rx_buf()
Product:	[Other] Security Response	Reporter:	Dhananjay Arunesh <darunesh>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	acaringi, allarkin, bhu, chwhite, crwood, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, ldoskova, lgoncalv, lzampier, nmurray, ptalbert, qzhao, rkeshri, rogbas, rrobaina, rvrbovsk, scweaver, security-response-team, tglozar, vkumar, walters, wcosta, williams, wmealing, ycote, ymankad
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	Kernel 5.18~19	Doc Type:	If docs needed, set a value
Doc Text:	A use-after-free flaw was found in vmxnet3_rq_alloc_rx_buf in drivers/net/vmxnet3/vmxnet3_drv.c in VMware's vmxnet3 ethernet NIC driver in the Linux Kernel. This issue could allow a local attacker to crash the system due to a double-free while cleaning up vmxnet3_rq_cleanup_all, which could also lead to a kernel information leak problem.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2219287, 2219288, 2232411, 2232412
Bug Blocks:	2219643

Description Dhananjay Arunesh 2023-07-03 07:04:44 UTC

A use-after-free flaw was found in vmxnet3_rq_alloc_rx_buf in drivers/net/vmxnet3/vmxnet3_drv.c in VMware's vmxnet3 ethernet NIC driver in the Linux Kernel. This flaw could allow a local attacker to crash the system due to a double free while cleanup at vmxnet3_rq_cleanup_all. This vulnerability could even lead to a kernel information leak problem.

In vmxnet3_rq_alloc_rx_buf(), when dma_map_single() fails, rbi->skb is freed immediately. Similarly, in another branch, when dma_map_page() fails, rbi->page is also freed. In the two cases, vmxnet3_rq_alloc_rx_buf() returns an error to its callers vmxnet3_rq_init() -> vmxnet3_rq_init_all() -> vmxnet3_activate_dev(). Then vmxnet3_activate_dev() calls vmxnet3_rq_cleanup_all() in error handling code, and rbi->skb or rbi->page are freed again in  vmxnet3_rq_cleanup_all(), causing use-after-free bugs.

References:
https://github.com/torvalds/linux/commit/9e7fef9521e73ca8afd7da9e58c14654b02dfad8