High · published June 24, 2026
In the Linux kernel, the following vulnerability has been resolved:
net/sched: taprio: fix use-after-free in advance_sched() on schedule switch
In advance_sched(), when should_change_schedules() returns true,
switch_schedules() is called to promote the admin schedule to oper.
switch_schedules() queues the old oper schedule for RCU freeing via
call_rcu(), but 'next' still points into an entry of the old oper
schedule. The subsequent 'next->end_time = end_time' and
rcu_assign_pointer(q->current_entry, next) are use-after-free.
Fix this by selecting 'next' from the new oper schedule immediately
after switch_schedules(), and using its pre-calculated end_time.
setup_first_end_time() sets the first entry's end_time to
base_time + interval when the schedule is installed, so the value
is already correct.
The deleted 'end_time = sched_base_time(admin)' assignment was also
harmful independently: it would overwrite the new first entry's
pre-calculated end_time with just base_time.
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 5.2, < 5.10.258 | 5.10.258 |
| linux/linux_kernel | ≥ 5.11, < 5.15.209 | 5.15.209 |
| linux/linux_kernel | ≥ 5.16, < 6.1.175 | 6.1.175 |
| linux/linux_kernel | ≥ 6.2, < 6.6.141 | 6.6.141 |
| linux/linux_kernel | ≥ 6.7, < 6.12.91 | 6.12.91 |
| linux/linux_kernel | ≥ 6.13, < 6.18.33 | 6.18.33 |
| linux/linux_kernel | ≥ 6.19, < 7.0.10 | 7.0.10 |