6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Fushuai Wang [ Upstream commit 0db4941d9dae159d887e7e2eac7e54e60c3aac87 ] Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in bpf_sk_storage.c to obtain better performance when PREEMPT_RCU is not enabled. Signed-off-by: Fushuai Wang Signed-off-by: Martin KaFai Lau Link: https://patch.msgid.link/20251007074011.12916-1-wangfushuai@baidu.com Stable-dep-of: 7cbd0c4cebe4 ("bpf: Fix UAF in sock clone early bailouts") Signed-off-by: Sasha Levin --- net/core/bpf_sk_storage.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c index 50ce498742596..135570dfcffe6 100644 --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -50,16 +50,14 @@ void bpf_sk_storage_free(struct sock *sk) { struct bpf_local_storage *sk_storage; - migrate_disable(); - rcu_read_lock(); + rcu_read_lock_dont_migrate(); sk_storage = rcu_dereference(sk->sk_bpf_storage); if (!sk_storage) goto out; bpf_local_storage_destroy(sk_storage); out: - rcu_read_unlock(); - migrate_enable(); + rcu_read_unlock_migrate(); } static void bpf_sk_storage_map_free(struct bpf_map *map) @@ -161,8 +159,7 @@ int bpf_sk_storage_clone(const struct sock *sk, struct sock *newsk) RCU_INIT_POINTER(newsk->sk_bpf_storage, NULL); - migrate_disable(); - rcu_read_lock(); + rcu_read_lock_dont_migrate(); sk_storage = rcu_dereference(sk->sk_bpf_storage); if (!sk_storage || hlist_empty(&sk_storage->list)) @@ -213,8 +210,7 @@ int bpf_sk_storage_clone(const struct sock *sk, struct sock *newsk) } out: - rcu_read_unlock(); - migrate_enable(); + rcu_read_unlock_migrate(); /* In case of an error, don't free anything explicitly here, the * caller is responsible to call bpf_sk_storage_free. -- 2.53.0