Fix: don't dereference NULL pointers

[deliverable/lttng-ust.git] / liblttng-ust-comm / lttng-ust-comm.c

diff --git a/liblttng-ust-comm/lttng-ust-comm.c b/liblttng-ust-comm/lttng-ust-comm.c
index 751ad2e3cf2add1ffd805c9ca4df802034e793b1..d213770f7a25f69059810d14d5f12569636cba2b 100644 (file)
--- a/liblttng-ust-comm/lttng-ust-comm.c
+++ b/liblttng-ust-comm/lttng-ust-comm.c
@@ -377,6 +377,8 @@ ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd)
        msg.msg_controllen = CMSG_LEN(sizeof_fds);
 
        cmptr = CMSG_FIRSTHDR(&msg);
+       if (!cmptr)
+               return -EINVAL;
        cmptr->cmsg_level = SOL_SOCKET;
        cmptr->cmsg_type = SCM_RIGHTS;
        cmptr->cmsg_len = CMSG_LEN(sizeof_fds);
@@ -390,7 +392,7 @@ ssize_t ustcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd)
        msg.msg_iovlen = 1;
 
        do {
-               ret = sendmsg(sock, &msg, 0);
+               ret = sendmsg(sock, &msg, MSG_NOSIGNAL);
        } while (ret < 0 && errno == EINTR);
        if (ret < 0) {
                /*
@@ -515,19 +517,27 @@ int ustcomm_recv_app_reply(int sock, struct ustcomm_ust_reply *lur,
        case 0: /* orderly shutdown */
                return -EPIPE;
        case sizeof(*lur):
+       {
+               int err = 0;
+
                if (lur->handle != expected_handle) {
                        ERR("Unexpected result message handle: "
                                "expected: %u vs received: %u\n",
                                expected_handle, lur->handle);
-                       return -EINVAL;
+                       err = 1;
                }
                if (lur->cmd != expected_cmd) {
                        ERR("Unexpected result message command "
                                "expected: %u vs received: %u\n",
                                expected_cmd, lur->cmd);
+                       err = 1;
+               }
+               if (err) {
                        return -EINVAL;
+               } else {
+                       return lur->ret_code;
                }
-               return lur->ret_code;
+       }
        default:
                if (len >= 0) {
                        ERR("incorrect message size: %zd\n", len);