[lxc-devel] [PATCH] coverity: rundir: Fix memory leaks

[Stéphane Graber]

Since we're no longer always returning a getenv result or some defined
string, the callers should cleanup the variable after use.

As a result, change from const char* to char*, add the needed free()
everywhere and use strdup() on strings coming from getenv.

Signed-off-by: Stéphane Graber <stgraber at ubuntu.com>
---
 src/lxc/lxclock.c | 11 +++++++++--
 src/lxc/monitor.c |  6 +++++-
 src/lxc/utils.c   | 23 +++++++++++++----------
 src/lxc/utils.h   |  2 +-
 4 files changed, 28 insertions(+), 14 deletions(-)

diff --git a/src/lxc/lxclock.c b/src/lxc/lxclock.c
index 598d6c0..b7a0078 100644
--- a/src/lxc/lxclock.c
+++ b/src/lxc/lxclock.c
@@ -98,7 +98,7 @@ static char *lxclock_name(const char *p, const char *n)
 	int ret;
 	int len;
 	char *dest;
-	const char *rundir;
+	char *rundir;
 
 	/* lockfile will be:
 	 * "/run" + "/lock/lxc/$lxcpath/$lxcname + '\0' if root
@@ -113,12 +113,15 @@ static char *lxclock_name(const char *p, const char *n)
 		return NULL;
 	len += strlen(rundir);
 
-	if ((dest = malloc(len)) == NULL)
+	if ((dest = malloc(len)) == NULL) {
+		free(rundir);
 		return NULL;
+	}
 
 	ret = snprintf(dest, len, "%s/lock/lxc/%s", rundir, p);
 	if (ret < 0 || ret >= len) {
 		free(dest);
+		free(rundir);
 		return NULL;
 	}
 	ret = mkdir_p(dest, 0755);
@@ -130,6 +133,7 @@ static char *lxclock_name(const char *p, const char *n)
 			d = realloc(dest, l2);
 			if (!d) {
 				free(dest);
+				free(rundir);
 				return NULL;
 			}
 			len = l2;
@@ -138,12 +142,15 @@ static char *lxclock_name(const char *p, const char *n)
 		ret = snprintf(dest, len, "/tmp/%d/lxc/%s", geteuid(), p);
 		if (ret < 0 || ret >= len) {
 			free(dest);
+			free(rundir);
 			return NULL;
 		}
 		ret = snprintf(dest, len, "/tmp/%d/lxc/%s/%s", geteuid(), p, n);
 	} else
 		ret = snprintf(dest, len, "%s/lock/lxc/%s/%s", rundir, p, n);
 
+	free(rundir);
+
 	if (ret < 0 || ret >= len) {
 		free(dest);
 		return NULL;
diff --git a/src/lxc/monitor.c b/src/lxc/monitor.c
index 704cc22..e45b5cf 100644
--- a/src/lxc/monitor.c
+++ b/src/lxc/monitor.c
@@ -54,7 +54,7 @@ int lxc_monitor_fifo_name(const char *lxcpath, char *fifo_path, size_t fifo_path
 			  int do_mkdirp)
 {
 	int ret;
-	const char *rundir;
+	char *rundir;
 
 	rundir = get_rundir();
 	if (!rundir)
@@ -64,19 +64,23 @@ int lxc_monitor_fifo_name(const char *lxcpath, char *fifo_path, size_t fifo_path
 		ret = snprintf(fifo_path, fifo_path_sz, "%s/lxc/%s", rundir, lxcpath);
 		if (ret < 0 || ret >= fifo_path_sz) {
 			ERROR("rundir/lxcpath (%s/%s) too long for monitor fifo", rundir, lxcpath);
+			free(rundir);
 			return -1;
 		}
 		ret = mkdir_p(fifo_path, 0755);
 		if (ret < 0) {
 			ERROR("unable to create monitor fifo dir %s", fifo_path);
+			free(rundir);
 			return ret;
 		}
 	}
 	ret = snprintf(fifo_path, fifo_path_sz, "%s/lxc/%s/monitor-fifo", rundir, lxcpath);
 	if (ret < 0 || ret >= fifo_path_sz) {
 		ERROR("rundir/lxcpath (%s/%s) too long for monitor fifo", rundir, lxcpath);
+		free(rundir);
 		return -1;
 	}
+	free(rundir);
 	return 0;
 }
 
diff --git a/src/lxc/utils.c b/src/lxc/utils.c
index db5cc19..c5c450d 100644
--- a/src/lxc/utils.c
+++ b/src/lxc/utils.c
@@ -376,7 +376,7 @@ out:
 	return values[i];
 }
 
-const char *get_rundir()
+char *get_rundir()
 {
 	char *rundir;
 	const char *homedir;
@@ -387,18 +387,21 @@ const char *get_rundir()
 	}
 
 	rundir = getenv("XDG_RUNTIME_DIR");
-	if (!rundir) {
-		INFO("XDG_RUNTIME_DIR isn't set in the environment.");
-		homedir = getenv("HOME");
-		if (!homedir) {
-			ERROR("HOME isn't set in the environment.");
-			return NULL;
-		}
+	if (rundir) {
+		rundir = strdup(rundir);
+		return rundir;
+	}
 
-		rundir = malloc(sizeof(char) * (17 + strlen(homedir)));
-		sprintf(rundir, "%s/.cache/lxc/run/", homedir);
+	INFO("XDG_RUNTIME_DIR isn't set in the environment.");
+	homedir = getenv("HOME");
+	if (!homedir) {
+		ERROR("HOME isn't set in the environment.");
+		return NULL;
 	}
 
+	rundir = malloc(sizeof(char) * (17 + strlen(homedir)));
+	sprintf(rundir, "%s/.cache/lxc/run/", homedir);
+
 	return rundir;
 }
 
diff --git a/src/lxc/utils.h b/src/lxc/utils.h
index f541253..f6f3373 100644
--- a/src/lxc/utils.h
+++ b/src/lxc/utils.h
@@ -39,7 +39,7 @@ extern void lxc_setup_fs(void);
 extern int get_u16(unsigned short *val, const char *arg, int base);
 extern int mkdir_p(const char *dir, mode_t mode);
 extern void remove_trailing_slashes(char *p);
-extern const char *get_rundir(void);
+extern char *get_rundir(void);
 
 extern const char *lxc_global_config_value(const char *option_name);
 
-- 
1.9.rc1