[PATCH] libselinux: declare return value of context_str(3) const

[Christian Göttsche <cgzones@xxxxxxxxxxxxxx>]

context_str(3) returns a string representation of the given context.
This string is owned by the context and free'd on context_free(3).
Declare it const, as already done in the man page, since it must not be
free'd by the caller.

Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
---
 libselinux/include/selinux/context.h |  2 +-
 libselinux/src/context.c             |  2 +-
 libselinux/src/get_context_list.c    | 11 ++++++-----
 libselinux/src/query_user_context.c  |  2 +-
 policycoreutils/newrole/newrole.c    |  2 +-
 5 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/libselinux/include/selinux/context.h b/libselinux/include/selinux/context.h
index 949fb1e1..82f4e690 100644
--- a/libselinux/include/selinux/context.h
+++ b/libselinux/include/selinux/context.h
@@ -25,7 +25,7 @@ extern "C" {
  * for the same context_t*
  */
 
-	extern char *context_str(context_t);
+	extern const char *context_str(context_t);
 
 /* Free the storage used by a context */
 	extern void context_free(context_t);
diff --git a/libselinux/src/context.c b/libselinux/src/context.c
index b2144c7c..9dddbc5a 100644
--- a/libselinux/src/context.c
+++ b/libselinux/src/context.c
@@ -116,7 +116,7 @@ void context_free(context_t context)
 /*
  * Return a pointer to the string value of the context.
  */
-char *context_str(context_t context)
+const char *context_str(context_t context)
 {
 	context_private_t *n = context->ptr;
 	int i;
diff --git a/libselinux/src/get_context_list.c b/libselinux/src/get_context_list.c
index cfe38e59..d774b9cf 100644
--- a/libselinux/src/get_context_list.c
+++ b/libselinux/src/get_context_list.c
@@ -143,6 +143,7 @@ static int get_context_user(FILE * fp,
 	char *linerole, *linetype;
 	char **new_reachable = NULL;
 	char *usercon_str;
+	const char *usercon_str2;
 	context_t con;
 	context_t usercon;
 
@@ -257,20 +258,20 @@ static int get_context_user(FILE * fp,
 			rc = -1;
 			goto out;
 		}
-		usercon_str = context_str(usercon);
-		if (!usercon_str) {
+		usercon_str2 = context_str(usercon);
+		if (!usercon_str2) {
 			context_free(usercon);
 			rc = -1;
 			goto out;
 		}
 
 		/* check whether usercon is already in reachable */
-		if (is_in_reachable(*reachable, usercon_str)) {
+		if (is_in_reachable(*reachable, usercon_str2)) {
 			context_free(usercon);
 			start = end;
 			continue;
 		}
-		if (security_check_context(usercon_str) == 0) {
+		if (security_check_context(usercon_str2) == 0) {
 			new_reachable = realloc(*reachable, (*nreachable + 2) * sizeof(char *));
 			if (!new_reachable) {
 				context_free(usercon);
@@ -278,7 +279,7 @@ static int get_context_user(FILE * fp,
 				goto out;
 			}
 			*reachable = new_reachable;
-			new_reachable[*nreachable] = strdup(usercon_str);
+			new_reachable[*nreachable] = strdup(usercon_str2);
 			if (new_reachable[*nreachable] == NULL) {
 				context_free(usercon);
 				rc = -1;
diff --git a/libselinux/src/query_user_context.c b/libselinux/src/query_user_context.c
index b8125c96..29a1b360 100644
--- a/libselinux/src/query_user_context.c
+++ b/libselinux/src/query_user_context.c
@@ -115,7 +115,7 @@ int manual_user_enter_context(const char *user, char ** newcon)
 	int mls_enabled = is_selinux_mls_enabled();
 
 	context_t new_context;	/* The new context chosen by the user     */
-	char *user_context = NULL;	/* String value of the user's context     */
+	const char *user_context = NULL;	/* String value of the user's context     */
 	int done = 0;		/* true if a valid sid has been obtained  */
 
 	/* Initialize the context.  How this is done depends on whether
diff --git a/policycoreutils/newrole/newrole.c b/policycoreutils/newrole/newrole.c
index ae37d725..c2afa37e 100644
--- a/policycoreutils/newrole/newrole.c
+++ b/policycoreutils/newrole/newrole.c
@@ -842,7 +842,7 @@ static int parse_command_line_arguments(int argc, char **argv, char *ttyn,
 	char *type_ptr = NULL;	/* stores malloc'd data from get_default_type */
 	char *level_s = NULL;	/* level spec'd by user in argv[] */
 	char *range_ptr = NULL;
-	char *new_con = NULL;
+	const char *new_con = NULL;
 	char *tty_con = NULL;
 	context_t context = NULL;	/* manipulatable form of new_context */
 	const struct option long_options[] = {
-- 
2.36.1