diff: fix SEGV (NULL deref) in diff -N
diff --git a/coreutils/diff.c b/coreutils/diff.c
index fa6ef10..911bfcf 100644
--- a/coreutils/diff.c
+++ b/coreutils/diff.c
@@ -997,24 +997,30 @@
{
int flags = D_HEADER;
int val;
+ char *fullpath1 = NULL; /* if -N */
+ char *fullpath2 = NULL;
- char *fullpath1 = concat_path_file(dir1, path1);
- char *fullpath2 = concat_path_file(dir2, path2);
+ if (path1)
+ fullpath1 = concat_path_file(dir1, path1);
+ if (path2)
+ fullpath2 = concat_path_file(dir2, path2);
- if (stat(fullpath1, &stb1) != 0) {
+ if (!fullpath1 || stat(fullpath1, &stb1) != 0) {
flags |= D_EMPTY1;
memset(&stb1, 0, sizeof(stb1));
- if (ENABLE_FEATURE_CLEAN_UP)
+ if (path2) {
free(fullpath1);
- fullpath1 = concat_path_file(dir1, path2);
+ fullpath1 = concat_path_file(dir1, path2);
+ }
}
- if (stat(fullpath2, &stb2) != 0) {
+ if (!fullpath2 || stat(fullpath2, &stb2) != 0) {
flags |= D_EMPTY2;
memset(&stb2, 0, sizeof(stb2));
stb2.st_mode = stb1.st_mode;
- if (ENABLE_FEATURE_CLEAN_UP)
+ if (path1) {
free(fullpath2);
- fullpath2 = concat_path_file(dir2, path1);
+ fullpath2 = concat_path_file(dir2, path1);
+ }
}
if (stb1.st_mode == 0)
@@ -1022,7 +1028,7 @@
if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
printf("Common subdirectories: %s and %s\n", fullpath1, fullpath2);
- return;
+ goto ret;
}
if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
@@ -1033,6 +1039,9 @@
val = diffreg(fullpath1, fullpath2, flags);
print_status(val, fullpath1, fullpath2, NULL);
+ ret:
+ free(fullpath1);
+ free(fullpath2);
}
#endif