From 0ac7ce964ed089a2614dbfcffb89bd6c4175992b Mon Sep 17 00:00:00 2001
From: Marc Hartmayer <mhartmay@linux.ibm.com>
Date: Wed, 8 Apr 2020 15:25:32 +0200
Subject: [PATCH] zipl/stage3: skip the equal sign when replacing
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Skip the equal sign when replacing the original command line.

Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
---
 zipl/boot/stage3.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/zipl/boot/stage3.c b/zipl/boot/stage3.c
index 115a2085..250c50e8 100644
--- a/zipl/boot/stage3.c
+++ b/zipl/boot/stage3.c
@@ -199,7 +199,10 @@ void start(void)
 	 * if extra parm string starts with '=' replace original string,
 	 * else append
 	 */
-	if (*cextra == 0x3d) {
+	if (*cextra == 0x3d && cextra_len >= 1) {
+		/* skip '=' */
+		cextra++;
+		cextra_len--;
 		memcpy(cmdline, cextra, cextra_len);
 	} else if (cmdline_len + 1 <= COMMAND_LINE_SIZE - 1) {
 		/* add blank */