CVE-2025-37879
CVE-2025-37879CVE-2025-37879
linux / linux_kernel
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)
Scoring
| CVSS | 9.8 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| Last modified | 2026-07-30 |