CVE-2025-68742
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
24/12/2025
Última modificación:
24/12/2025
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
bpf: Fix invalid prog->stats access when update_effective_progs fails<br />
<br />
Syzkaller triggers an invalid memory access issue following fault<br />
injection in update_effective_progs. The issue can be described as<br />
follows:<br />
<br />
__cgroup_bpf_detach<br />
update_effective_progs<br />
compute_effective_progs<br />
bpf_prog_array_alloc items[index] = &dummy_bpf_prog.prog<br />
<br />
---softirq start---<br />
__do_softirq<br />
...<br />
__cgroup_bpf_run_filter_skb<br />
__bpf_prog_run_save_cb<br />
bpf_prog_run<br />
stats = this_cpu_ptr(prog->stats)<br />
/* invalid memory access */<br />
flags = u64_stats_update_begin_irqsave(&stats->syncp)<br />
---softirq end---<br />
<br />
static_branch_dec(&cgroup_bpf_enabled_key[atype])<br />
<br />
The reason is that fault injection caused update_effective_progs to fail<br />
and then changed the original prog into dummy_bpf_prog.prog in<br />
purge_effective_progs. Then a softirq came, and accessing the members of<br />
dummy_bpf_prog.prog in the softirq triggers invalid mem access.<br />
<br />
To fix it, skip updating stats when stats is NULL.



