diff mbox series

[net-next,04/10] udp: move udp->gro_enabled to udp->udp_flags

Message ID 20230912091730.1591459-5-edumazet@google.com (mailing list archive)
State Accepted
Commit e1dc0615c6b08ef36414f08c011965b8fb56198b
Delegated to: Netdev Maintainers
Headers show
Series udp: round of data-races fixes | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3257 this patch: 3257
netdev/cc_maintainers warning 1 maintainers not CCed: dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 1555 this patch: 1555
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 3506 this patch: 3506
netdev/checkpatch warning WARNING: line length of 88 exceeds 80 columns WARNING: line length of 93 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet Sept. 12, 2023, 9:17 a.m. UTC 
syzbot reported that udp->gro_enabled can be read locklessly.
Use one atomic bit from udp->udp_flags.

Fixes: e20cf8d3f1f7 ("udp: implement GRO for plain UDP sockets.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/linux/udp.h    | 2 +-
 net/ipv4/udp.c         | 6 +++---
 net/ipv4/udp_offload.c | 4 ++--
 net/ipv6/udp.c         | 2 +-
 4 files changed, 7 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/udp.h b/include/linux/udp.h
index 8d4c3835b1b219da9c830f53f09aa0511840a1d4..b344bd2e41fc9f4abf953c29c644b11438b0057d 100644
--- a/include/linux/udp.h
+++ b/include/linux/udp.h
@@ -36,6 +36,7 @@  enum {
 	UDP_FLAGS_CORK,		/* Cork is required */
 	UDP_FLAGS_NO_CHECK6_TX, /* Send zero UDP6 checksums on TX? */
 	UDP_FLAGS_NO_CHECK6_RX, /* Allow zero UDP6 checksums on RX? */
+	UDP_FLAGS_GRO_ENABLED,	/* Request GRO aggregation */
 };
 
 struct udp_sock {
@@ -54,7 +55,6 @@  struct udp_sock {
 					   * different encapsulation layer set
 					   * this
 					   */
-			 gro_enabled:1,	/* Request GRO aggregation */
 			 accept_udp_l4:1,
 			 accept_udp_fraglist:1;
 /* indicator bits used by pcflag: */
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index cb32826a1db20006ce9c21e66a9347f41b228da2..1debc10a0f029e47ffe90aaff60727b6bb7309cc 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1868,7 +1868,7 @@  int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags,
 						      (struct sockaddr *)sin);
 	}
 
-	if (udp_sk(sk)->gro_enabled)
+	if (udp_test_bit(GRO_ENABLED, sk))
 		udp_cmsg_recv(msg, sk, skb);
 
 	if (inet_cmsg_flags(inet))
@@ -2713,7 +2713,7 @@  int udp_lib_setsockopt(struct sock *sk, int level, int optname,
 		/* when enabling GRO, accept the related GSO packet type */
 		if (valbool)
 			udp_tunnel_encap_enable(sk->sk_socket);
-		up->gro_enabled = valbool;
+		udp_assign_bit(GRO_ENABLED, sk, valbool);
 		up->accept_udp_l4 = valbool;
 		release_sock(sk);
 		break;
@@ -2803,7 +2803,7 @@  int udp_lib_getsockopt(struct sock *sk, int level, int optname,
 		break;
 
 	case UDP_GRO:
-		val = up->gro_enabled;
+		val = udp_test_bit(GRO_ENABLED, sk);
 		break;
 
 	/* The following two cannot be changed on UDP sockets, the return is
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 0f46b3c2e4ac5427a5d39586086048afe22f34f1..6c95d28d0c4a7e56d587a986113b3711f8de964c 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -557,10 +557,10 @@  struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
 	NAPI_GRO_CB(skb)->is_flist = 0;
 	if (!sk || !udp_sk(sk)->gro_receive) {
 		if (skb->dev->features & NETIF_F_GRO_FRAGLIST)
-			NAPI_GRO_CB(skb)->is_flist = sk ? !udp_sk(sk)->gro_enabled : 1;
+			NAPI_GRO_CB(skb)->is_flist = sk ? !udp_test_bit(GRO_ENABLED, sk) : 1;
 
 		if ((!sk && (skb->dev->features & NETIF_F_GRO_UDP_FWD)) ||
-		    (sk && udp_sk(sk)->gro_enabled) || NAPI_GRO_CB(skb)->is_flist)
+		    (sk && udp_test_bit(GRO_ENABLED, sk)) || NAPI_GRO_CB(skb)->is_flist)
 			return call_gro_receive(udp_gro_receive_segment, head, skb);
 
 		/* no GRO, be sure flush the current packet */
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 6e1ea3029260ec6e4992cf7e01c0202fabd94017..2c3281879b6dfdf04bf219cf9b13c1c59f732a0d 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -413,7 +413,7 @@  int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 						      (struct sockaddr *)sin6);
 	}
 
-	if (udp_sk(sk)->gro_enabled)
+	if (udp_test_bit(GRO_ENABLED, sk))
 		udp_cmsg_recv(msg, sk, skb);
 
 	if (np->rxopt.all)