Description
In the Linux kernel, the following vulnerability has been resolved: 9p/net: fix improper handling of bogus negative read/write replies In p9_client_write() and p9_client_read_once(), if the server incorrectly replies with success but a negative write/read count then we would consider written (negative) <= rsize (positive) because both variables were signed. Make variables unsigned to avoid this problem. The reproducer linked below now fails with the following error instead of a null pointer deref: 9pnet: bogus RWRITE count (4294967295 > 3)
Affected products
linux: linux kernel; debian: debian linux
References6
- git.kernel.org/stable/c/374e4cd75617c8c2552f562f39dd989583f5c330 Patch
- git.kernel.org/stable/c/468ff4a7c61fb811c596a7c44b6a5455e40fd12b Patch
- git.kernel.org/stable/c/a68768e280b7d0c967ea509e791bb9b90adc94a5 Patch
- git.kernel.org/stable/c/c548f95688e2b5ae0e2ae43d53cf717156c7d034 Patch
- git.kernel.org/stable/c/d0259a856afca31d699b706ed5e2adf11086c73b Patch
- lists.debian.org/debian-lts-announce/2025/05/msg00045.html Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 1% percentile: 54 · as of 7 November 2026
- CWE
- CWE-125
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