Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Cross-merge networking fixes after downstream PR (net-6.13-rc8).

Conflicts:

drivers/net/ethernet/realtek/r8169_main.c
  1f691a1fc4be ("r8169: remove redundant hwmon support")
  152d00a91396 ("r8169: simplify setting hwmon attribute visibility")
https://lore.kernel.org/20250115122152.760b4e8d@canb.auug.org.au

Adjacent changes:

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  152f4da05aee ("bnxt_en: add support for rx-copybreak ethtool command")
  f0aa6a37a3db ("eth: bnxt: always recalculate features after XDP clearing, fix null-deref")

drivers/net/ethernet/intel/ice/ice_type.h
  50327223a8bb ("ice: add lock to protect low latency interface")
  dc26548d729e ("ice: Fix quad registers read on E825")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 27 insertions, 19 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 4bc0a0686fcd..c472c9a57cf6 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -576,7 +576,7 @@ begin:
 	return NULL;
 }
 
-/* In hash4, rehash can happen in connect(), where hash4_cnt keeps unchanged. */
+/* udp_rehash4() only checks hslot4, and hash4_cnt is not processed. */
 static void udp_rehash4(struct udp_table *udptable, struct sock *sk,
 			u16 newhash4)
 {
@@ -625,15 +625,13 @@ void udp_lib_hash4(struct sock *sk, u16 hash)
 	struct net *net = sock_net(sk);
 	struct udp_table *udptable;
 
-	/* Connected udp socket can re-connect to another remote address,
-	 * so rehash4 is needed.
+	/* Connected udp socket can re-connect to another remote address, which
+	 * will be handled by rehash. Thus no need to redo hash4 here.
 	 */
-	udptable = net->ipv4.udp_table;
-	if (udp_hashed4(sk)) {
-		udp_rehash4(udptable, sk, hash);
+	if (udp_hashed4(sk))
 		return;
-	}
 
+	udptable = net->ipv4.udp_table;
 	hslot = udp_hashslot(udptable, net, udp_sk(sk)->udp_port_hash);
 	hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
 	hslot4 = udp_hashslot4(udptable, hash);
@@ -2229,14 +2227,14 @@ void udp_lib_rehash(struct sock *sk, u16 newhash, u16 newhash4)
 		struct udp_table *udptable = udp_get_table_prot(sk);
 		struct udp_hslot *hslot, *hslot2, *nhslot2;
 
+		hslot = udp_hashslot(udptable, sock_net(sk),
+				     udp_sk(sk)->udp_port_hash);
 		hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
 		nhslot2 = udp_hashslot2(udptable, newhash);
 		udp_sk(sk)->udp_portaddr_hash = newhash;
 
 		if (hslot2 != nhslot2 ||
 		    rcu_access_pointer(sk->sk_reuseport_cb)) {
-			hslot = udp_hashslot(udptable, sock_net(sk),
-					     udp_sk(sk)->udp_port_hash);
 			/* we must lock primary chain too */
 			spin_lock_bh(&hslot->lock);
 			if (rcu_access_pointer(sk->sk_reuseport_cb))
@@ -2255,19 +2253,29 @@ void udp_lib_rehash(struct sock *sk, u16 newhash, u16 newhash4)
 				spin_unlock(&nhslot2->lock);
 			}
 
-			if (udp_hashed4(sk)) {
-				udp_rehash4(udptable, sk, newhash4);
+			spin_unlock_bh(&hslot->lock);
+		}
+
+		/* Now process hash4 if necessary:
+		 * (1) update hslot4;
+		 * (2) update hslot2->hash4_cnt.
+		 * Note that hslot2/hslot4 should be checked separately, as
+		 * either of them may change with the other unchanged.
+		 */
+		if (udp_hashed4(sk)) {
+			spin_lock_bh(&hslot->lock);
 
-				if (hslot2 != nhslot2) {
-					spin_lock(&hslot2->lock);
-					udp_hash4_dec(hslot2);
-					spin_unlock(&hslot2->lock);
+			udp_rehash4(udptable, sk, newhash4);
+			if (hslot2 != nhslot2) {
+				spin_lock(&hslot2->lock);
+				udp_hash4_dec(hslot2);
+				spin_unlock(&hslot2->lock);
 
-					spin_lock(&nhslot2->lock);
-					udp_hash4_inc(nhslot2);
-					spin_unlock(&nhslot2->lock);
-				}
+				spin_lock(&nhslot2->lock);
+				udp_hash4_inc(nhslot2);
+				spin_unlock(&nhslot2->lock);
 			}
+
 			spin_unlock_bh(&hslot->lock);
 		}
 	}