tools: hv: Check return value of poll call

Check return value of poll call and if it fails print error
to the system log. If errno is EINVAL then exit with non-zero
value otherwise continue the while loop and call poll again.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Acked-by:  K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 10 insertions, 1 deletions

diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index ae9aa1cd97fe..81cbb6ecce89 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -1490,7 +1490,16 @@ int main(void)
                 socklen_t addr_l = sizeof(addr);
                 pfd.events = POLLIN;
                 pfd.revents = 0;
-                poll(&pfd, 1, -1);
+
+                if (poll(&pfd, 1, -1) < 0) {
+                        syslog(LOG_ERR, "poll failed; error: %d %s", errno, strerror(errno));
+                        if (errno == EINVAL) {
+                                close(fd);
+                                exit(EXIT_FAILURE);
+                        }
+                        else
+                                continue;
+                }
 
                 len = recvfrom(fd, kvp_recv_buffer, sizeof(kvp_recv_buffer), 0,
                                 addr_p, &addr_l);