Bug 2283393 (CVE-2021-47556)

Summary: CVE-2021-47556 kernel: ethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce()
Product: [Other] Security Response Reporter: ybuenos
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: acaringi, allarkin, aquini, bhu, chwhite, cye, cyin, dbohanno, debarbos, dfreiber, drow, dvlasenk, esandeen, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, ldoskova, lgoncalv, lzampier, mleitner, mmilgram, mstowell, nmurray, ptalbert, rkeshri, rparrazo, rrobaina, rvrbovsk, rysulliv, scweaver, sidakwo, sukulkar, tglozar, tyberry, vkumar, wcosta, williams, wmealing, ycote, ykopkova, zhijwang
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: kernel 5.15.6, kernel 5.16 Doc Type: If docs needed, set a value
Doc Text:
A vulnerability was found in the Linux kernel's ethtool implementation in the ioctl handling of coalesce settings, where the system attempts to change coalesce settings using the ethtool_set_coalesce() function without verifying the availability of both the .get_coalesce() and .set_coalesce() callbacks, leading to a potential NULL pointer dereference causing system instability and crashes during network operations.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2283496    

Description ybuenos 2024-05-27 09:40:41 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce()

The Linux kernel CVE team has assigned CVE-2021-47556 to this issue.

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024052443-CVE-2021-47556-558e@gregkh/T
Comment 2 Alex 2024-06-09 15:44:31 UTC 
The result of automatic check (that is developed by Alexander Larkin) for this CVE-2021-47556 is: CHECK	Maybe valid. Check manually. with impact MODERATE (that is approximation based on flags DANGER NULLPTR IMPROVEONLY  ; these flags parsed automatically based on patche data). Such automatic check happens only for Low/Moderates (and only when not from reporter, but parsing already existing CVE). Highs always checked manually (I check it myself and then we check it again in Remediation team). In rare cases some of the Moderates could be increased to High later.