From: Mathias Kresin <dev@kresin.me>
Date: Mon, 26 Jun 2017 17:22:52 +0000 (+0200)
Subject: firmware-utils: fix dgn3500sum compiler warnings
X-Git-Tag: v17.01.3~88
X-Git-Url: http://git.openwrt.org/?p=openwrt%2Fopenwrt.git;a=commitdiff_plain;h=6c03b293bb2ba86f22ea6e20dd0266892932f585

firmware-utils: fix dgn3500sum compiler warnings

The sum variable need to be initialised, otherwise it will points to
random stack memory and a bogus image checksum might be calculated.

While at it, fix the segfault in case the product region code isn't
specified and enable compiler warnings which had revealed all the code
issues.

Signed-off-by: Mathias Kresin <dev@kresin.me>
---

diff --git a/tools/firmware-utils/Makefile b/tools/firmware-utils/Makefile
index 69cba69a58..337d63582e 100644
--- a/tools/firmware-utils/Makefile
+++ b/tools/firmware-utils/Makefile
@@ -73,7 +73,7 @@ define Host/Compile
 	$(call cc,mkdcs932, -Wall)
 	$(call cc,mkheader_gemtek,-lz)
 	$(call cc,mkrtn56uimg, -lz)
-	$(call cc,dgn3500sum)
+	$(call cc,dgn3500sum, -Wall)
 	$(call cc,edimax_fw_header, -Wall)
 	$(call cc,mkmerakifw sha1, -Wall)
 	$(call cc,mkmerakifw-old, -Wall)
diff --git a/tools/firmware-utils/src/dgn3500sum.c b/tools/firmware-utils/src/dgn3500sum.c
index 00a0c5f837..eb80e6c01b 100644
--- a/tools/firmware-utils/src/dgn3500sum.c
+++ b/tools/firmware-utils/src/dgn3500sum.c
@@ -103,7 +103,7 @@ int main(int argc, char** argv)
   unsigned long start, i;
   char *endptr, *buffer, *p;
   int count;  // size of file in bytes
-  unsigned short sum, sum1;
+  unsigned short sum = 0, sum1 = 0;
   char sumbuf[9];
 
   if(argc < 3) {
@@ -117,7 +117,7 @@ int main(int argc, char** argv)
     printf("ERROR: File not writeable!\n");
     return 1;
   }
-  if(argc = 4)
+  if(argc == 4)
   {
     printf("%s: PID type: %s\n", argv[0], argv[3]);
     if(strcmp(argv[3], "DE")==0)
@@ -147,7 +147,6 @@ int main(int argc, char** argv)
 
   start = strtol(argv[2], &endptr, 16);
   p = buffer+start;
-  sum1 = 0;
   for(i = 0; i < count - start; i++)
   {
 	sum1 += p[i];