Vulnerability Details CVE-2025-71090
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix nfsd_file reference leak in nfsd4_add_rdaccess_to_wrdeleg()
nfsd4_add_rdaccess_to_wrdeleg() unconditionally overwrites
fp->fi_fds[O_RDONLY] with a newly acquired nfsd_file. However, if
the client already has a SHARE_ACCESS_READ open from a previous OPEN
operation, this action overwrites the existing pointer without
releasing its reference, orphaning the previous reference.
Additionally, the function originally stored the same nfsd_file
pointer in both fp->fi_fds[O_RDONLY] and fp->fi_rdeleg_file with
only a single reference. When put_deleg_file() runs, it clears
fi_rdeleg_file and calls nfs4_file_put_access() to release the file.
However, nfs4_file_put_access() only releases fi_fds[O_RDONLY] when
the fi_access[O_RDONLY] counter drops to zero. If another READ open
exists on the file, the counter remains elevated and the nfsd_file
reference from the delegation is never released. This potentially
causes open conflicts on that file.
Then, on server shutdown, these leaks cause __nfsd_file_cache_purge()
to encounter files with an elevated reference count that cannot be
cleaned up, ultimately triggering a BUG() in kmem_cache_destroy()
because there are still nfsd_file objects allocated in that cache.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.0
EPSS Ranking 7.6%
CVSS Severity
CVSS v3 Score 5.5
Products affected by CVE-2025-71090
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cpe:2.3:o:linux:linux_kernel:6.17
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cpe:2.3:o:linux:linux_kernel:6.17.1
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cpe:2.3:o:linux:linux_kernel:6.17.10
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cpe:2.3:o:linux:linux_kernel:6.17.11
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cpe:2.3:o:linux:linux_kernel:6.17.12
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cpe:2.3:o:linux:linux_kernel:6.17.13
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cpe:2.3:o:linux:linux_kernel:6.17.2
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cpe:2.3:o:linux:linux_kernel:6.17.3
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cpe:2.3:o:linux:linux_kernel:6.17.4
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cpe:2.3:o:linux:linux_kernel:6.17.5
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cpe:2.3:o:linux:linux_kernel:6.17.6
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cpe:2.3:o:linux:linux_kernel:6.17.7
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cpe:2.3:o:linux:linux_kernel:6.17.8
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cpe:2.3:o:linux:linux_kernel:6.17.9
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cpe:2.3:o:linux:linux_kernel:6.18
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cpe:2.3:o:linux:linux_kernel:6.18.1
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cpe:2.3:o:linux:linux_kernel:6.18.2
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cpe:2.3:o:linux:linux_kernel:6.18.3
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cpe:2.3:o:linux:linux_kernel:6.19