CVE-2026-31437: Linux

Описание

Оригинално описание

In the Linux kernel, the following vulnerability has been resolved: netfs: Fix NULL pointer dereference in netfs_unbuffered_write() on retry When a write subrequest is marked NETFS_SREQ_NEED_RETRY, the retry path in netfs_unbuffered_write() unconditionally calls stream->prepare_write() without checking if it is NULL. Filesystems such as 9P do not set the prepare_write operation, so stream->prepare_write remains NULL. When get_user_pages() fails with -EFAULT and the subrequest is flagged for retry, this results in a NULL pointer dereference at fs/netfs/direct_write.c:189. Fix this by mirroring the pattern already used in write_retry.c: if stream->prepare_write is NULL, skip renegotiation and directly reissue the subrequest via netfs_reissue_write(), which handles iterator reset, IN_PROGRESS flag, stats update and reissue internally.

Засегнати продукти

• Linux Linux: 72d08d2839649d1c5efbe375751f4473fa4486af преди a4d1b4ba9754bac3efebd06f583a44a7af52c0ab; 0c29f6d63122a0168d67cb8ecde5b4cf7fe4acb0 преди 7a5482f5ce891decbf36f2e6fab1e9fc4a76a684; a0b4c7a49137ed21279f354eb59f49ddae8dffc2 преди e9075e420a1eb3b52c60f3b95893a55e77419ce8
• Linux Linux: 6.18.17 преди 6.18.21; 6.19.7 преди 6.19.11

История

Други уязвимости в Linux Linux

• 8.1CVE-2026-99270
• 7.8CVE-2026-99269
• CVE-2026-99268
• CVE-2026-99266
• CVE-2026-99267

Първоизточници

• https://www.cve.org/CVERecord?id=CVE-2026-31437
• https://nvd.nist.gov/vuln/detail/CVE-2026-31437
• https://git.kernel.org/stable/c/a4d1b4ba9754bac3efebd06f583a44a7af52c0ab
• https://git.kernel.org/stable/c/7a5482f5ce891decbf36f2e6fab1e9fc4a76a684
• https://git.kernel.org/stable/c/e9075e420a1eb3b52c60f3b95893a55e77419ce8