CVE-2026-68441
CVE-2026-68441CVE-2026-68441
Description
In the Linux kernel, the following vulnerability has been resolved:
net/sched: Handle TC_ACT_REDIRECT from qdisc filter chains
When a TC filter attached to a qdisc filter chain returns
TC_ACT_REDIRECT (ex: via an eBPF program calling bpf_redirect() or an
act_bpf action), the redirect was silently lost i.e no qdisc classify
function handled TC_ACT_REDIRECT, so the packet fell through the
switch and was enqueued normally instead of being redirected.
This has been broken since bpf_redirect() was introduced for TC in
commit 27b29f63058d ("bpf: add bpf_redirect() helper"). We got lucky
for a long time because bpf_net_context was a per-CPU variable that
was always available.
commit 401cb7dae813 ("net: Reference bpf_redirect_info via task_struct
on PREEMPT_RT.") turned bpf_net_context into a task_struct member that
is only set up by explicit callers. Without a caller setting it up,
bpf_redirect() itself crashes with a NULL pointer dereference in
bpf_net_ctx_get_ri(). However, even with bp
Scoring
| Last modified | 2026-08-12 |