cgroups: remove stack allocations

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index d359b67fcd5377abde8ebcdaef0322f8d480fbdf..9d886ac17d037998f5d84d158eeb04bc514c9f82 100644 (file)
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -58,6 +58,7 @@
 #include "config.h"
 #include "log.h"
 #include "macro.h"
+#include "memory_utils.h"
 #include "storage/storage.h"
 #include "utils.h"
 
@@ -888,15 +889,18 @@ static bool controller_in_clist(char *cgline, char *c)
                return false;
 
        len = eol - cgline;
-       tmp = alloca(len + 1);
+       tmp = must_realloc(NULL, len + 1);
        memcpy(tmp, cgline, len);
        tmp[len] = '\0';
 
        lxc_iterate_parts(tok, tmp, ",") {
-               if (strcmp(tok, c) == 0)
+               if (strcmp(tok, c) == 0) {
+                       free(tmp);
                        return true;
+               }
        }
 
+       free(tmp);
        return false;
 }
 
@@ -2209,15 +2213,12 @@ __cgfsng_ops static int cgfsng_get(struct cgroup_ops *ops, const char *filename,
                                     char *value, size_t len, const char *name,
                                     const char *lxcpath)
 {
-       int ret = -1;
-       size_t controller_len;
-       char *controller, *p, *path;
+       __do_free char *controller;
+       char *p, *path;
        struct hierarchy *h;
+       int ret = -1;
 
-       controller_len = strlen(filename);
-       controller = alloca(controller_len + 1);
-       (void)strlcpy(controller, filename, controller_len + 1);
-
+       controller = must_copy_string(filename);
        p = strchr(controller, '.');
        if (p)
                *p = '\0';
@@ -2248,15 +2249,12 @@ __cgfsng_ops static int cgfsng_set(struct cgroup_ops *ops,
                                     const char *filename, const char *value,
                                     const char *name, const char *lxcpath)
 {
-       int ret = -1;
-       size_t controller_len;
-       char *controller, *p, *path;
+       __do_free char *controller;
+       char *p, *path;
        struct hierarchy *h;
+       int ret = -1;
 
-       controller_len = strlen(filename);
-       controller = alloca(controller_len + 1);
-       (void)strlcpy(controller, filename, controller_len + 1);
-
+       controller = must_copy_string(filename);
        p = strchr(controller, '.');
        if (p)
                *p = '\0';
@@ -2363,18 +2361,14 @@ out:
 static int cg_legacy_set_data(struct cgroup_ops *ops, const char *filename,
                              const char *value)
 {
-       size_t len;
+       __do_free char *controller;
        char *fullpath, *p;
        /* "b|c <2^64-1>:<2^64-1> r|w|m" = 47 chars max */
        char converted_value[50];
        struct hierarchy *h;
        int ret = 0;
-       char *controller = NULL;
-
-       len = strlen(filename);
-       controller = alloca(len + 1);
-       (void)strlcpy(controller, filename, len + 1);
 
+       controller = must_copy_string(filename);
        p = strchr(controller, '.');
        if (p)
                *p = '\0';