tools: kwboot: Initialize rfds to zero

Explicitly zero out the rfds fd_set with FD_ZERO() before using it.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>

diff --git a/tools/kwboot.c b/tools/kwboot.c
index 7e1be29..695d433 100644 (file)
--- a/tools/kwboot.c
+++ b/tools/kwboot.c
@@ -1151,6 +1151,7 @@ kwboot_terminal(int tty)
                fd_set rfds;
                int nfds = 0;
 
+               FD_ZERO(&rfds);
                FD_SET(tty, &rfds);
                nfds = nfds < tty ? tty : nfds;