Description
In the Linux kernel, the following vulnerability has been resolved: NFSv4.1: zero referring call lists before decoding decode_cb_sequence_args() allocates csa_rclists with kmalloc_objs(), so each referring_call_list starts uninitialized. decode_rc_list() assigns rcl_refcalls only when rcl_nrefcalls is nonzero. A valid list with zero referring calls therefore leaves the pointer uninitialized, and nfs4_callback_sequence() later passes stale slab contents to kfree(). Allocate csa_rclists with kzalloc_objs() so every rcl_refcalls member is NULL from the beginning, including valid empty referring call lists.
References6
- git.kernel.org/stable/c/7510a5b9edec9d9536a4e69f10edfb2592e6cf7f
- git.kernel.org/stable/c/810f6b3a29ac96fdc16909132b31627dae6824c2
- git.kernel.org/stable/c/8fa4804fe62ca4155a2d8fc2789d630376cbf2fc
- git.kernel.org/stable/c/ed54460caf5b5aa65ec03c9a6032d831f39f19f5
- git.kernel.org/stable/c/f31f3c042e024aef437cda42f0424ae8d4594b6c
- git.kernel.org/stable/c/f4d23937e1c41995c2f54af26c89b5e48a41c299
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 55 · as of 8 November 2026
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