CVE-2026-53243
In the Linux kernel, the following vulnerability has been resolved: rseq: Fix using an uninitialized stack variable in rseq_exit_user_update() There is an bug in which an uninitialized stack variable is used in rseq_exit_user_update() as reported by syzbot: BUG: KMSAN: kernel-infoleak in rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline] The local variable: struct rseq_ids ids = { .cpu_id = task_cpu(t), .mm_cid = task_mm_cid(t), .node_id = cpu_to_node(ids.cpu_id), }; According to the C standard, the evaluation order of expressions in an initializer list is indeterminately sequenced. The compiler (Clang, in this KMSAN build) evaluates `cpu_to_node(ids.cpu_id)` *before* `ids.cpu_id` is initialized with `task_cpu(t)`. This is fixed by moving the assignment of ids.node_id outside the structure initialization.
- Score
- CVSS 3.1 5.5 Medium
- Status
- Analyzed - 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- Published
- 2026-06-25
- Last modified
- 2026-06-25
- Weaknesses
- CWE-908
Affected products
References
- https://git.kernel.org/stable/c/6d99479799c69c3cb588fcda19c81d8f61d64ecd
- https://git.kernel.org/stable/c/e12d20a63b61aaf9de4772effccf42cc9a003e58
