[PATCH 1/1] pxe: simplify label_boot()

[Heinrich Schuchardt]

Coverity CID 131256 indicates a possible buffer overflow in label_boot().
This would only occur if the size of the downloaded file would exceed 4
GiB. But anyway we can simplify the code by using snprintf() and checking
the return value.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
---
 boot/pxe_utils.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/boot/pxe_utils.c b/boot/pxe_utils.c
index a7a84f26c1..5841561bdf 100644
--- a/boot/pxe_utils.c
+++ b/boot/pxe_utils.c
@@ -465,11 +465,10 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 		}
 
 		initrd_addr_str = env_get("ramdisk_addr_r");
-		strcpy(initrd_filesize, simple_xtoa(size));
-
-		strncpy(initrd_str, initrd_addr_str, 18);
-		strcat(initrd_str, ":");
-		strncat(initrd_str, initrd_filesize, 9);
+		size = snprintf(initrd_str, sizeof(initrd_str), "%s:%lx",
+				initrd_addr_str, size);
+		if (size >= sizeof(initrd_str))
+			return 1;
 	}
 
 	if (get_relfile_envaddr(ctx, label->kernel, "kernel_addr_r",
-- 
2.32.0