CVE - CVE-2021-47506

CVE-ID
CVE-2021-47506	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix use-after-free due to delegation race A delegation break could arrive as soon as we've called vfs_setlease. A delegation break runs a callback which immediately (in nfsd4_cb_recall_prepare) adds the delegation to del_recall_lru. If we then exit nfs4_set_delegation without hashing the delegation, it will be freed as soon as the callback is done with it, without ever being removed from del_recall_lru. Symptoms show up later as use-after-free or list corruption warnings, usually in the laundromat thread. I suspect aba2072f4523 "nfsd: grant read delegations to clients holding writes" made this bug easier to hit, but I looked as far back as v3.0 and it looks to me it already had the same problem. So I'm not sure where the bug was introduced; it may have been there from the beginning.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce URL:https://git.kernel.org/stable/c/04a8d07f3d58308b92630045560799a3faa3ebce MISC:https://git.kernel.org/stable/c/148c816f10fd11df27ca6a9b3238cdd42fa72cd3 URL:https://git.kernel.org/stable/c/148c816f10fd11df27ca6a9b3238cdd42fa72cd3 MISC:https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4 URL:https://git.kernel.org/stable/c/2becaa990b93cbd2928292c0b669d3abb6cf06d4 MISC:https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee URL:https://git.kernel.org/stable/c/33645d3e22720cac1e4548f8fef57bf0649536ee MISC:https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4 URL:https://git.kernel.org/stable/c/348714018139c39533c55661a0c7c990671396b4 MISC:https://git.kernel.org/stable/c/548ec0805c399c65ed66c6641be467f717833ab5 URL:https://git.kernel.org/stable/c/548ec0805c399c65ed66c6641be467f717833ab5 MISC:https://git.kernel.org/stable/c/e0759696de6851d7536efddfdd2dfed4c4df1f09 URL:https://git.kernel.org/stable/c/e0759696de6851d7536efddfdd2dfed4c4df1f09 MISC:https://git.kernel.org/stable/c/eeb0711801f5e19ef654371b627682aed3b11373 URL:https://git.kernel.org/stable/c/eeb0711801f5e19ef654371b627682aed3b11373
Assigning CNA
kernel.org
Date Record Created
20240522	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20240522)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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