From 6423ac2eb31ec33f8526dc48f1e541b665333970 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 11 Nov 2022 16:00:21 +0000 Subject: [PATCH] rxrpc: Fix oops from calling udpv6_sendmsg() on AF_INET socket If rxrpc sees an IPv6 address, it assumes it can call udpv6_sendmsg() on it - even if it got it on an IPv4 socket. Fix do_udp_sendmsg() to give an error in such a case. general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] ... RIP: 0010:ipv6_addr_v4mapped include/net/ipv6.h:749 [inline] RIP: 0010:udpv6_sendmsg+0xd0a/0x2c70 net/ipv6/udp.c:1361 ... Call Trace: do_udp_sendmsg net/rxrpc/output.c:27 [inline] do_udp_sendmsg net/rxrpc/output.c:21 [inline] rxrpc_send_abort_packet+0x73b/0x860 net/rxrpc/output.c:367 rxrpc_release_calls_on_socket+0x211/0x300 net/rxrpc/call_object.c:595 rxrpc_release_sock net/rxrpc/af_rxrpc.c:886 [inline] rxrpc_release+0x263/0x5a0 net/rxrpc/af_rxrpc.c:917 __sock_release+0xcd/0x280 net/socket.c:650 sock_close+0x18/0x20 net/socket.c:1365 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16b/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb35/0x2a20 kernel/exit.c:820 do_group_exit+0xd0/0x2a0 kernel/exit.c:950 __do_sys_exit_group kernel/exit.c:961 [inline] __se_sys_exit_group kernel/exit.c:959 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:959 Fixes: ed472b0c8783 ("rxrpc: Call udp_sendmsg() directly") Reported-by: Eric Dumazet Suggested-by: Eric Dumazet Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org --- net/rxrpc/output.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c index 46432e70a16b..a2fe1a262f8a 100644 --- a/net/rxrpc/output.c +++ b/net/rxrpc/output.c @@ -18,15 +18,21 @@ extern int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len); -static ssize_t do_udp_sendmsg(struct socket *sk, struct msghdr *msg, size_t len) +static ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len) { -#if IS_ENABLED(CONFIG_AF_RXRPC_IPV6) struct sockaddr *sa = msg->msg_name; + struct sock *sk = socket->sk; - if (sa->sa_family == AF_INET6) - return udpv6_sendmsg(sk->sk, msg, len); -#endif - return udp_sendmsg(sk->sk, msg, len); + if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6)) { + if (sa->sa_family == AF_INET6) { + if (sk->sk_family != AF_INET6) { + pr_warn("AF_INET6 address on AF_INET socket\n"); + return -ENOPROTOOPT; + } + return udpv6_sendmsg(sk, msg, len); + } + } + return udp_sendmsg(sk, msg, len); } struct rxrpc_abort_buffer {