[PATCH 1/3] libselinux: simplify string copying

[Christian Göttsche <cgzones@xxxxxxxxxxxxxx>]

Use strdup(3)/strndup(3) instead of allocating memory and then manually
copying the content.

Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
---
 libselinux/src/context.c                     | 11 +++++------
 libselinux/src/get_default_type.c            |  3 +--
 libselinux/src/matchpathcon.c                |  9 +++------
 libselinux/utils/selabel_lookup_best_match.c | 10 ++++------
 4 files changed, 13 insertions(+), 20 deletions(-)

diff --git a/libselinux/src/context.c b/libselinux/src/context.c
index 9dddbc5a..8830bf42 100644
--- a/libselinux/src/context.c
+++ b/libselinux/src/context.c
@@ -149,19 +149,18 @@ static int set_comp(context_private_t * n, int idx, const char *str)
 	char *t = NULL;
 	const char *p;
 	if (str) {
-		t = (char *)malloc(strlen(str) + 1);
-		if (!t) {
-			return -1;
-		}
 		for (p = str; *p; p++) {
 			if (*p == '\t' || *p == '\n' || *p == '\r' ||
 			    ((*p == ':' || *p == ' ') && idx != COMP_RANGE)) {
-				free(t);
 				errno = EINVAL;
 				return -1;
 			}
 		}
-		strcpy(t, str);
+
+		t = strdup(str);
+		if (!t) {
+			return -1;
+		}
 	}
 	conditional_free(&n->component[idx]);
 	n->component[idx] = t;
diff --git a/libselinux/src/get_default_type.c b/libselinux/src/get_default_type.c
index dd7b5d79..766ea4b7 100644
--- a/libselinux/src/get_default_type.c
+++ b/libselinux/src/get_default_type.c
@@ -62,10 +62,9 @@ static int find_default_type(FILE * fp, const char *role, char **type)
 		return -1;
 	}
 
-	t = malloc(strlen(buf) - len);
+	t = strndup(ptr, strlen(buf) - len - 1);
 	if (!t)
 		return -1;
-	strcpy(t, ptr);
 	*type = t;
 	return 0;
 }
diff --git a/libselinux/src/matchpathcon.c b/libselinux/src/matchpathcon.c
index ea78a23e..bf2da083 100644
--- a/libselinux/src/matchpathcon.c
+++ b/libselinux/src/matchpathcon.c
@@ -215,10 +215,9 @@ int matchpathcon_filespec_add(ino_t ino, int specind, const char *file)
 			if (ret < 0 || sb.st_ino != ino) {
 				fl->specind = specind;
 				free(fl->file);
-				fl->file = malloc(strlen(file) + 1);
+				fl->file = strdup(file);
 				if (!fl->file)
 					goto oom;
-				strcpy(fl->file, file);
 				return fl->specind;
 
 			}
@@ -232,10 +231,9 @@ int matchpathcon_filespec_add(ino_t ino, int specind, const char *file)
 			     __FUNCTION__, file, fl->file,
 			     con_array[fl->specind]);
 			free(fl->file);
-			fl->file = malloc(strlen(file) + 1);
+			fl->file = strdup(file);
 			if (!fl->file)
 				goto oom;
-			strcpy(fl->file, file);
 			return fl->specind;
 		}
 
@@ -248,10 +246,9 @@ int matchpathcon_filespec_add(ino_t ino, int specind, const char *file)
 		goto oom;
 	fl->ino = ino;
 	fl->specind = specind;
-	fl->file = malloc(strlen(file) + 1);
+	fl->file = strdup(file);
 	if (!fl->file)
 		goto oom_freefl;
-	strcpy(fl->file, file);
 	fl->next = prevfl->next;
 	prevfl->next = fl;
 	return fl->specind;
diff --git a/libselinux/utils/selabel_lookup_best_match.c b/libselinux/utils/selabel_lookup_best_match.c
index a4af0679..e816c04b 100644
--- a/libselinux/utils/selabel_lookup_best_match.c
+++ b/libselinux/utils/selabel_lookup_best_match.c
@@ -30,7 +30,7 @@ static __attribute__ ((__noreturn__)) void usage(const char *progname)
 	exit(1);
 }
 
-static mode_t string_to_mode(char *s)
+static mode_t string_to_mode(const char *s)
 {
 	switch (s[0]) {
 	case 'b':
@@ -53,7 +53,7 @@ static mode_t string_to_mode(char *s)
 
 int main(int argc, char **argv)
 {
-	int raw = 0, mode = 0, rc, opt, i, num_links, string_len;
+	int raw = 0, mode = 0, rc, opt, i, num_links;
 	char *validate = NULL, *path = NULL, *context = NULL, *file = NULL;
 	char **links = NULL;
 
@@ -101,13 +101,11 @@ int main(int argc, char **argv)
 		}
 
 		for (i = optind, num_links = 0; i < argc; i++, num_links++) {
-			string_len = strlen(argv[i]) + 1;
-			links[num_links] = malloc(string_len);
+			links[num_links] = strdup(argv[i]);
 			if (!links[num_links]) {
-				fprintf(stderr, "ERROR: malloc failed.\n");
+				fprintf(stderr, "ERROR: strdup failed.\n");
 				exit(1);
 			}
-			strcpy(links[num_links], argv[i]);
 		}
 	}
 
-- 
2.38.1