[U-Boot] [PATCH] fpga: xilinx: Avoid using local intermediate buffer

[Michal Simek]

From: Siva Durga Prasad Paladugu <siva.durga.paladugu at xilinx.com>

Dont use local temporary buffer for printing out the
info instead use directly from memroy. This fixes the
issue of stack corruprion due to local buffer overflow.

Signed-off-by: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

 drivers/fpga/xilinx.c | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/fpga/xilinx.c b/drivers/fpga/xilinx.c
index 2cd0104d8b15..941f30010a54 100644
--- a/drivers/fpga/xilinx.c
+++ b/drivers/fpga/xilinx.c
@@ -29,7 +29,6 @@ int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
 {
 	unsigned int length;
 	unsigned int swapsize;
-	char buffer[80];
 	unsigned char *dataptr;
 	unsigned int i;
 	const fpga_desc *desc;
@@ -57,10 +56,8 @@ int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
 
 	length = (*dataptr << 8) + *(dataptr + 1);
 	dataptr += 2;
-	for (i = 0; i < length; i++)
-		buffer[i] = *dataptr++;
-
-	printf("  design filename = \"%s\"\n", buffer);
+	printf("  design filename = \"%s\"\n", dataptr);
+	dataptr += length;
 
 	/* get part number (identifier, length, string) */
 	if (*dataptr++ != 0x62) {
@@ -71,23 +68,22 @@ int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
 
 	length = (*dataptr << 8) + *(dataptr + 1);
 	dataptr += 2;
-	for (i = 0; i < length; i++)
-		buffer[i] = *dataptr++;
 
 	if (xdesc->name) {
-		i = (ulong)strstr(buffer, xdesc->name);
+		i = (ulong)strstr((char *)dataptr, xdesc->name);
 		if (!i) {
 			printf("%s: Wrong bitstream ID for this device\n",
 			       __func__);
 			printf("%s: Bitstream ID %s, current device ID %d/%s\n",
-			       __func__, buffer, devnum, xdesc->name);
+			       __func__, dataptr, devnum, xdesc->name);
 			return FPGA_FAIL;
 		}
 	} else {
 		printf("%s: Please fill correct device ID to xilinx_desc\n",
 		       __func__);
 	}
-	printf("  part number = \"%s\"\n", buffer);
+	printf("  part number = \"%s\"\n", dataptr);
+	dataptr += length;
 
 	/* get date (identifier, length, string) */
 	if (*dataptr++ != 0x63) {
@@ -98,9 +94,8 @@ int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
 
 	length = (*dataptr << 8) + *(dataptr+1);
 	dataptr += 2;
-	for (i = 0; i < length; i++)
-		buffer[i] = *dataptr++;
-	printf("  date = \"%s\"\n", buffer);
+	printf("  date = \"%s\"\n", dataptr);
+	dataptr += length;
 
 	/* get time (identifier, length, string) */
 	if (*dataptr++ != 0x64) {
@@ -111,9 +106,8 @@ int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
 
 	length = (*dataptr << 8) + *(dataptr+1);
 	dataptr += 2;
-	for (i = 0; i < length; i++)
-		buffer[i] = *dataptr++;
-	printf("  time = \"%s\"\n", buffer);
+	printf("  time = \"%s\"\n", dataptr);
+	dataptr += length;
 
 	/* get fpga data length (identifier, length) */
 	if (*dataptr++ != 0x65) {
-- 
1.9.1