summaryrefslogtreecommitdiffstats
path: root/net/ipv6/udp.c
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2021-06-30 18:42:44 +0200
committerDavid S. Miller <davem@davemloft.net>2021-07-01 22:23:19 +0200
commit18a419bad63b7f68a1979e28459782518e7b6bbe (patch)
treee6c3fcc5fb6a03acdb1c70a889670234f3c8ad98 /net/ipv6/udp.c
parenttcp: consistently disable header prediction for mptcp (diff)
downloadlinux-18a419bad63b7f68a1979e28459782518e7b6bbe.tar.xz
linux-18a419bad63b7f68a1979e28459782518e7b6bbe.zip
udp: annotate data races around unix_sk(sk)->gso_size
Accesses to unix_sk(sk)->gso_size are lockless. Add READ_ONCE()/WRITE_ONCE() around them. BUG: KCSAN: data-race in udp_lib_setsockopt / udpv6_sendmsg write to 0xffff88812d78f47c of 2 bytes by task 10849 on cpu 1: udp_lib_setsockopt+0x3b3/0x710 net/ipv4/udp.c:2696 udpv6_setsockopt+0x63/0x90 net/ipv6/udp.c:1630 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3265 __sys_setsockopt+0x18f/0x200 net/socket.c:2104 __do_sys_setsockopt net/socket.c:2115 [inline] __se_sys_setsockopt net/socket.c:2112 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2112 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88812d78f47c of 2 bytes by task 10852 on cpu 0: udpv6_sendmsg+0x161/0x16b0 net/ipv6/udp.c:1299 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:642 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0x360/0x4d0 net/socket.c:2337 ___sys_sendmsg net/socket.c:2391 [inline] __sys_sendmmsg+0x315/0x4b0 net/socket.c:2477 __do_sys_sendmmsg net/socket.c:2506 [inline] __se_sys_sendmmsg net/socket.c:2503 [inline] __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2503 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000 -> 0x0005 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10852 Comm: syz-executor.0 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/udp.c')
-rw-r--r--net/ipv6/udp.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 368972dbd919..0cc7ba531b34 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1296,7 +1296,7 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
ipcm6_init(&ipc6);
- ipc6.gso_size = up->gso_size;
+ ipc6.gso_size = READ_ONCE(up->gso_size);
ipc6.sockc.tsflags = sk->sk_tsflags;
ipc6.sockc.mark = sk->sk_mark;