6.15-stable review patch. If anyone has any objections, please let me know.
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From: Hyunwoo Kim imv4bel@gmail.com
commit b160766e26d4e2e2d6fe2294e0b02f92baefcec5 upstream.
Since taprio’s taprio_dev_notifier() isn’t protected by an RCU read-side critical section, a race with advance_sched() can lead to a use-after-free.
Adding rcu_read_lock() inside taprio_dev_notifier() prevents this.
Fixes: fed87cc6718a ("net/sched: taprio: automatically calculate queueMaxSDU based on TC gate durations") Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim imv4bel@gmail.com Reviewed-by: Simon Horman horms@kernel.org Reviewed-by: Eric Dumazet edumazet@google.com Link: https://patch.msgid.link/aEzIYYxt0is9upYG@v4bel-B760M-AORUS-ELITE-AX Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sched/sch_taprio.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1328,13 +1328,15 @@ static int taprio_dev_notifier(struct no
stab = rtnl_dereference(q->root->stab);
- oper = rtnl_dereference(q->oper_sched); + rcu_read_lock(); + oper = rcu_dereference(q->oper_sched); if (oper) taprio_update_queue_max_sdu(q, oper, stab);
- admin = rtnl_dereference(q->admin_sched); + admin = rcu_dereference(q->admin_sched); if (admin) taprio_update_queue_max_sdu(q, admin, stab); + rcu_read_unlock();
break; }