CVEvulnerability
CVE-2026-98075
- Status
- Undergoing Analysis
- Published
- 2026-09-25
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
bpf: reject BPF_PSEUDO_FUNC reference to the main program
fixups.c:jit_subprogs() rewrites BPF_PSEUDO_FUNC loads to contain real
function addresses. This function is invoked from bpf_jit_subprogs()
only when env->subprog_cnt > 1. Meaning that for any program like
below:
int main(void *ctx) {
void *ptr = main;
...
bpf_timer_set_callback(..., ptr);
...
}
The 'ptr' won't be ever converted to contain an address.
In combination with e.g. bpf_timer_set_callback() this would lead to a
function call at a bogus address.
Instead of complicating the implementation, just assume that no useful
program needs main to be a sync or async callback and reject
BPF_PSEUDO_FUNC loads for the main subprogram.
References
- https://git.kernel.org/stable/c/118212417ba0120d99f84154799f8880f07411f4 git.kernel.org
- https://git.kernel.org/stable/c/314c8caa9cb64ad60c5b969fe9a3e2dcdccf156f git.kernel.org
- https://git.kernel.org/stable/c/374b2c5561db80fcdd7cdce44af37a49416f61c7 git.kernel.org
- https://git.kernel.org/stable/c/8cb75f7ada25b1cf25f2f74dec3ba649b9064a09 git.kernel.org
- https://git.kernel.org/stable/c/92f0bd0e2b632c6565ac2214a4d7d2ed37e5b9f6 git.kernel.org
- https://git.kernel.org/stable/c/c74750dca96f40a1adb9d334f5a3152f44b270c3 git.kernel.org
- https://git.kernel.org/stable/c/d6c39774ae093c9f7009cc4ae918f18fc1af7ae7 git.kernel.org