diff options
author | Eric Dumazet <edumazet@google.com> | 2023-09-22 06:42:20 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2023-10-01 21:39:19 +0300 |
commit | c4480eb5504c9771f935cbca58a3b874bdd36af8 (patch) | |
tree | 557c1fe16766040ad2c71c784a1e88fd90977997 | |
parent | 959d5c11601b2b337c364b2e3102d392365e3dd3 (diff) | |
download | linux-c4480eb5504c9771f935cbca58a3b874bdd36af8.tar.xz |
inet: lockless IP_PKTOPTIONS implementation
Current implementation is already lockless, because the socket
lock is released before reading socket fields.
Add missing READ_ONCE() annotations.
Note that corresponding WRITE_ONCE() are needed, the order
of the patches do not really matter.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/ipv4/ip_sockglue.c | 76 |
1 files changed, 37 insertions, 39 deletions
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 58995526c6e9..1ee01ff64171 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -1633,6 +1633,43 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, return -ENOTCONN; goto copyval; } + case IP_PKTOPTIONS: + { + struct msghdr msg; + + if (sk->sk_type != SOCK_STREAM) + return -ENOPROTOOPT; + + if (optval.is_kernel) { + msg.msg_control_is_user = false; + msg.msg_control = optval.kernel; + } else { + msg.msg_control_is_user = true; + msg.msg_control_user = optval.user; + } + msg.msg_controllen = len; + msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; + + if (inet_test_bit(PKTINFO, sk)) { + struct in_pktinfo info; + + info.ipi_addr.s_addr = READ_ONCE(inet->inet_rcv_saddr); + info.ipi_spec_dst.s_addr = READ_ONCE(inet->inet_rcv_saddr); + info.ipi_ifindex = READ_ONCE(inet->mc_index); + put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); + } + if (inet_test_bit(TTL, sk)) { + int hlim = READ_ONCE(inet->mc_ttl); + + put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim); + } + if (inet_test_bit(TOS, sk)) { + int tos = READ_ONCE(inet->rcv_tos); + put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos); + } + len -= msg.msg_controllen; + return copy_to_sockptr(optlen, &len, sizeof(int)); + } case IP_UNICAST_IF: val = (__force int)htonl((__u32) READ_ONCE(inet->uc_index)); goto copyval; @@ -1678,45 +1715,6 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname, else err = ip_get_mcast_msfilter(sk, optval, optlen, len); goto out; - case IP_PKTOPTIONS: - { - struct msghdr msg; - - sockopt_release_sock(sk); - - if (sk->sk_type != SOCK_STREAM) - return -ENOPROTOOPT; - - if (optval.is_kernel) { - msg.msg_control_is_user = false; - msg.msg_control = optval.kernel; - } else { - msg.msg_control_is_user = true; - msg.msg_control_user = optval.user; - } - msg.msg_controllen = len; - msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; - - if (inet_test_bit(PKTINFO, sk)) { - struct in_pktinfo info; - - info.ipi_addr.s_addr = inet->inet_rcv_saddr; - info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr; - info.ipi_ifindex = inet->mc_index; - put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info); - } - if (inet_test_bit(TTL, sk)) { - int hlim = READ_ONCE(inet->mc_ttl); - - put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim); - } - if (inet_test_bit(TOS, sk)) { - int tos = inet->rcv_tos; - put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos); - } - len -= msg.msg_controllen; - return copy_to_sockptr(optlen, &len, sizeof(int)); - } case IP_LOCAL_PORT_RANGE: val = inet->local_port_range.hi << 16 | inet->local_port_range.lo; break; |