From: Eric Dumazet edumazet@google.com
[ Upstream commit 153a0d187e767c68733b8e9f46218eb1f41ab902 ]
For some reason, raw_bind() forgot to lock the socket.
BUG: KCSAN: data-race in __ip4_datagram_connect / raw_bind
write to 0xffff8881170d4308 of 4 bytes by task 5466 on cpu 0: raw_bind+0x1b0/0x250 net/ipv4/raw.c:739 inet_bind+0x56/0xa0 net/ipv4/af_inet.c:443 __sys_bind+0x14b/0x1b0 net/socket.c:1697 __do_sys_bind net/socket.c:1708 [inline] __se_sys_bind net/socket.c:1706 [inline] __x64_sys_bind+0x3d/0x50 net/socket.c:1706 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae
read to 0xffff8881170d4308 of 4 bytes by task 5468 on cpu 1: __ip4_datagram_connect+0xb7/0x7b0 net/ipv4/datagram.c:39 ip4_datagram_connect+0x2a/0x40 net/ipv4/datagram.c:89 inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576 __sys_connect_file net/socket.c:1900 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1917 __do_sys_connect net/socket.c:1927 [inline] __se_sys_connect net/socket.c:1924 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:1924 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae
value changed: 0x00000000 -> 0x0003007f
Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 5468 Comm: syz-executor.5 Not tainted 5.17.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/raw.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index 7d26e0f8bdaeb..5d95f80314f95 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -721,6 +721,7 @@ static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) int ret = -EINVAL; int chk_addr_ret;
+ lock_sock(sk); if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in)) goto out;
@@ -740,7 +741,9 @@ static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) inet->inet_saddr = 0; /* Use device */ sk_dst_reset(sk); ret = 0; -out: return ret; +out: + release_sock(sk); + return ret; }
/*