Adding upstream version 4.19.304.upstream/4.19.304upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 29 insertions, 9 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 616e84d16..81888513b 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1152,6 +1152,7 @@ struct proto {
 	/*
 	 * Pressure flag: try to collapse.
 	 * Technical note: it is used by multiple contexts non atomically.
+	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
 	 * All the __sk_mem_schedule() is of this nature: accounting
 	 * is strict, actions are advisory and have some latency.
 	 */
@@ -1265,6 +1266,12 @@ static inline bool sk_has_memory_pressure(const struct sock *sk)
 	return sk->sk_prot->memory_pressure != NULL;
 }
 
+static inline bool sk_under_global_memory_pressure(const struct sock *sk)
+{
+	return sk->sk_prot->memory_pressure &&
+		!!READ_ONCE(*sk->sk_prot->memory_pressure);
+}
+
 static inline bool sk_under_memory_pressure(const struct sock *sk)
 {
 	if (!sk->sk_prot->memory_pressure)
@@ -1274,7 +1281,7 @@ static inline bool sk_under_memory_pressure(const struct sock *sk)
 	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
 		return true;
 
-	return !!*sk->sk_prot->memory_pressure;
+	return !!READ_ONCE(*sk->sk_prot->memory_pressure);
 }
 
 static inline long
@@ -1328,7 +1335,7 @@ proto_memory_pressure(struct proto *prot)
 {
 	if (!prot->memory_pressure)
 		return false;
-	return !!*prot->memory_pressure;
+	return !!READ_ONCE(*prot->memory_pressure);
 }
 
 
@@ -1752,21 +1759,33 @@ static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
 		return;
-	sk->sk_tx_queue_mapping = tx_queue;
+	/* Paired with READ_ONCE() in sk_tx_queue_get() and
+	 * other WRITE_ONCE() because socket lock might be not held.
+	 */
+	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
 }
 
 #define NO_QUEUE_MAPPING	USHRT_MAX
 
 static inline void sk_tx_queue_clear(struct sock *sk)
 {
-	sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
+	/* Paired with READ_ONCE() in sk_tx_queue_get() and
+	 * other WRITE_ONCE() because socket lock might be not held.
+	 */
+	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
 }
 
 static inline int sk_tx_queue_get(const struct sock *sk)
 {
-	if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
-		return sk->sk_tx_queue_mapping;
+	if (sk) {
+		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
+		 * and sk_tx_queue_set().
+		 */
+		int val = READ_ONCE(sk->sk_tx_queue_mapping);
 
+		if (val != NO_QUEUE_MAPPING)
+			return val;
+	}
 	return -1;
 }
 
@@ -1840,6 +1859,7 @@ static inline void sock_graft(struct sock *sk, struct socket *parent)
 }
 
 kuid_t sock_i_uid(struct sock *sk);
+unsigned long __sock_i_ino(struct sock *sk);
 unsigned long sock_i_ino(struct sock *sk);
 
 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
@@ -1898,7 +1918,7 @@ static inline void dst_negative_advice(struct sock *sk)
 		if (ndst != dst) {
 			rcu_assign_pointer(sk->sk_dst_cache, ndst);
 			sk_tx_queue_clear(sk);
-			sk->sk_dst_pending_confirm = 0;
+			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
 		}
 	}
 }
@@ -1909,7 +1929,7 @@ __sk_dst_set(struct sock *sk, struct dst_entry *dst)
 	struct dst_entry *old_dst;
 
 	sk_tx_queue_clear(sk);
-	sk->sk_dst_pending_confirm = 0;
+	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
 					    lockdep_sock_is_held(sk));
 	rcu_assign_pointer(sk->sk_dst_cache, dst);
@@ -1922,7 +1942,7 @@ sk_dst_set(struct sock *sk, struct dst_entry *dst)
 	struct dst_entry *old_dst;
 
 	sk_tx_queue_clear(sk);
-	sk->sk_dst_pending_confirm = 0;
+	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
 	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
 	dst_release(old_dst);
 }