Bug 1225052 (CVE-2021-47316) - VUL-0: CVE-2021-47316: kernel: nfsd: fix NULL dereference in nfs3svc_encode_getaclres
Summary: VUL-0: CVE-2021-47316: kernel: nfsd: fix NULL dereference in nfs3svc_encode_g...
Status: RESOLVED FIXED
Alias: CVE-2021-47316
Product: SUSE Security Incidents
Classification: Novell Products
Component: Incidents (show other bugs)
Version: unspecified
Hardware: Other Other
: P3 - Medium : Normal
Target Milestone: ---
Assignee: Security Team bot
QA Contact: Security Team bot
URL: https://smash.suse.de/issue/406952/
Whiteboard: CVSSv3.1:SUSE:CVE-2021-47316:5.5:(AV:...
Keywords:
Depends on:
Blocks:
 
Reported: 2024-05-22 16:30 UTC by SMASH SMASH
Modified: 2024-05-29 12:05 UTC (History)
2 users (show)

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Found By: Security Response Team
Services Priority:
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Blocker: ---
Marketing QA Status: ---
IT Deployment: ---

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Description SMASH SMASH 2024-05-22 16:30:23 UTC 
In the Linux kernel, the following vulnerability has been resolved:

nfsd: fix NULL dereference in nfs3svc_encode_getaclres

In error cases the dentry may be NULL.

Before 20798dfe249a, the encoder also checked dentry and
d_really_is_positive(dentry), but that looks like overkill to me--zero
status should be enough to guarantee a positive dentry.

This isn't the first time we've seen an error-case NULL dereference
hidden in the initialization of a local variable in an xdr encoder.  But
I went back through the other recent rewrites and didn't spot any
similar bugs.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-47316
https://www.cve.org/CVERecord?id=CVE-2021-47316
https://git.kernel.org/stable/c/650e6f383a6eb40f7c0a010982a74ab4b6893870
https://git.kernel.org/stable/c/ab1016d39cc052064e32f25ad18ef8767a0ee3b8
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2021/CVE-2021-47316.mbox
Comment 2 Andrea Mattiazzo 2024-05-29 12:05:41 UTC 
All done, closing.