tcp: Add SIGPIPE on sendmsg for a broken connection

Correct UNIX behavior requires a SIGPIPE when the connection is broken (i.e we can't send or they won't listen). Add a nice common helper while we're at it. Signed-off-by: Pedro Falcato <[email protected]>
heatd · Jan 31, 2025 · 6838c3a · 6838c3a
1 parent 4098752
commit 6838c3a
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Showing 3 changed files with 20 additions and 6 deletions.
diff --git a/kernel/include/onyx/net/socket.h b/kernel/include/onyx/net/socket.h
@@ -426,6 +426,8 @@ static inline void sock_discharge_rmem_pbf(struct socket *sock, struct packetbuf
     sock_discharge_rmem_bytes(sock, pbf->total_len);
 }
 
+int sock_stream_error(struct socket *sock, int err, int flags);
+
 __END_CDECLS
 
 #endif
diff --git a/kernel/kernel/net/socket.cpp b/kernel/kernel/net/socket.cpp
@@ -14,6 +14,7 @@
 #include <onyx/net/netkernel.h>
 #include <onyx/net/socket.h>
 #include <onyx/poll.h>
+#include <onyx/process.h>
 #include <onyx/scoped_lock.h>
 #include <onyx/utils.h>
 
@@ -1500,3 +1501,10 @@ int socket::setsockopt(int level, int optname, const void *optval, socklen_t opt
         return -ENOPROTOOPT;
     return setsockopt_socket_level(optname, optval, optlen);
 }
+
+int sock_stream_error(struct socket *sock, int err, int flags)
+{
+    if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
+        kernel_raise_signal(SIGPIPE, get_current_process(), 0, NULL);
+    return err;
+}
diff --git a/kernel/kernel/net/tcp.cpp b/kernel/kernel/net/tcp.cpp
@@ -951,16 +951,20 @@ ssize_t tcp_sendmsg(struct socket *sock_, const msghdr *msg, int flags)
     scoped_hybrid_lock g{sock->socket_lock, sock};
 
     if (sock->has_sock_err())
-        return sock->consume_sock_err();
+        return sock_stream_error(sock, sock->consume_sock_err(), flags);
 
-    if (!tcp_state_is_fl(sock, TCPF_STATE_CLOSE_WAIT | TCPF_STATE_ESTABLISHED))
+    if (sock->shutdown_state & SHUTDOWN_WR ||
+        !tcp_state_is_fl(sock, TCPF_STATE_CLOSE_WAIT | TCPF_STATE_ESTABLISHED))
     {
-        err = -ENOTCONN;
+        err = -EPIPE;
         if (sock->state == TCP_STATE_SYN_SENT)
+        {
             err = tcp_wait_conn(sock);
-        if (!err && sock->state != TCP_STATE_ESTABLISHED)
-            err = -ENOTCONN;
-        return err;
+            if (!err && sock->state != TCP_STATE_ESTABLISHED)
+                err = -ENOTCONN;
+        }
+
+        return sock_stream_error(sock, err, flags);
     }
 
     auto len = iovec_count_length(msg->msg_iov, msg->msg_iovlen);