diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-08-08 13:58:09 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-08-09 15:32:43 -0700 |
| commit | 1ded5e5a5931bb8b31e15b63b655fe232e3416b2 (patch) | |
| tree | 3de66ab540b62ffb536b625c204ccdbb7ff6a8c4 /net/unix | |
| parent | e05a53ab867c106a3f21a806599ef885c67e59bd (diff) | |
net: annotate data-races around sock->ops
IPV6_ADDRFORM socket option is evil, because it can change sock->ops
while other threads might read it. Same issue for sk->sk_family
being set to AF_INET.
Adding READ_ONCE() over sock->ops reads is needed for sockets
that might be impacted by IPV6_ADDRFORM.
Note that mptcp_is_tcpsk() can also overwrite sock->ops.
Adding annotations for all sk->sk_family reads will require
more patches :/
BUG: KCSAN: data-race in ____sys_sendmsg / do_ipv6_setsockopt
write to 0xffff888109f24ca0 of 8 bytes by task 4470 on cpu 0:
do_ipv6_setsockopt+0x2c5e/0x2ce0 net/ipv6/ipv6_sockglue.c:491
ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012
udpv6_setsockopt+0x95/0xa0 net/ipv6/udp.c:1690
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3663
__sys_setsockopt+0x1c3/0x230 net/socket.c:2273
__do_sys_setsockopt net/socket.c:2284 [inline]
__se_sys_setsockopt net/socket.c:2281 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2281
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
read to 0xffff888109f24ca0 of 8 bytes by task 4469 on cpu 1:
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
____sys_sendmsg+0x349/0x4c0 net/socket.c:2503
___sys_sendmsg net/socket.c:2557 [inline]
__sys_sendmmsg+0x263/0x500 net/socket.c:2643
__do_sys_sendmmsg net/socket.c:2672 [inline]
__se_sys_sendmmsg net/socket.c:2669 [inline]
__x64_sys_sendmmsg+0x57/0x60 net/socket.c:2669
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
value changed: 0xffffffff850e32b8 -> 0xffffffff850da890
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4469 Comm: syz-executor.1 Not tainted 6.4.0-rc5-syzkaller-00313-g4c605260bc60 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230808135809.2300241-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/unix')
| -rw-r--r-- | net/unix/scm.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/unix/scm.c b/net/unix/scm.c index f9152881d77f..e9dde7176c8a 100644 --- a/net/unix/scm.c +++ b/net/unix/scm.c @@ -29,10 +29,11 @@ struct sock *unix_get_socket(struct file *filp) /* Socket ? */ if (S_ISSOCK(inode->i_mode) && !(filp->f_mode & FMODE_PATH)) { struct socket *sock = SOCKET_I(inode); + const struct proto_ops *ops = READ_ONCE(sock->ops); struct sock *s = sock->sk; /* PF_UNIX ? */ - if (s && sock->ops && sock->ops->family == PF_UNIX) + if (s && ops && ops->family == PF_UNIX) u_sock = s; } else { /* Could be an io_uring instance */ |