From 538b8f2935ce8c925a9c2b23c41aa2a8dd65a31f Mon Sep 17 00:00:00 2001
From: Su_Laus <[EMAIL REDACTED]>
Date: Mon, 6 Feb 2023 21:23:13 +0100
Subject: [PATCH] test_ifd_loop_detection: fix Coverity Scan issue CID 1520750:
Null pointer dereferences (NULL_RETURNS) line 55.
---
test/test_ifd_loop_detection.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/test/test_ifd_loop_detection.c b/test/test_ifd_loop_detection.c
index 99a749e5..02421f66 100644
--- a/test/test_ifd_loop_detection.c
+++ b/test/test_ifd_loop_detection.c
@@ -36,30 +36,34 @@
#include "tiffio.h"
+/* Compare 'requested_dir_number' with number written in PageName tag
+ * into the IFD to identify that IFD. */
int is_requested_directory(TIFF *tif, int requested_dir_number,
const char *filename)
{
- char *ptr;
+ char *ptr = NULL;
+ char *auxStr = NULL;
if (!TIFFGetField(tif, TIFFTAG_PAGENAME, &ptr))
{
fprintf(stderr, "Can't get TIFFTAG_PAGENAME tag.\n");
return 0;
}
- /* Retrieve directory number from ASCII string */
- char *auxStr = strchr(ptr, ' ');
- int nthIFD;
- nthIFD = atoi(ptr);
-
/* Check for reading errors */
- if (strncmp(auxStr, " th.", 4))
+ if (ptr != NULL)
+ auxStr = strchr(ptr, ' ');
+
+ if (ptr == NULL || auxStr == NULL || strncmp(auxStr, " th.", 4))
{
+ ptr = ptr == NULL ? "(null)" : ptr;
fprintf(stderr,
"Error reading IFD directory number from PageName tag: %s\n",
ptr);
return 0;
}
+ /* Retrieve IFD identification number from ASCII string */
+ const int nthIFD = atoi(ptr);
if (nthIFD == requested_dir_number)
{
return 1;