From: Hyunwoo Kim <imv4bel@gmail.com> stable inclusion from stable-v6.6.95 commit 8c5713ce1ced75f9e9ed5c642ea3d2ba06ead69c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICIW71 CVE: CVE-2025-38087 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- 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> Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com> --- net/sched/sch_taprio.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 951a87909c29..d162e2dd8602 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1338,13 +1338,15 @@ static int taprio_dev_notifier(struct notifier_block *nb, unsigned long event, 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; } -- 2.25.1