commands_utils: convert to strnprintf()

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

diff --git a/src/lxc/commands_utils.c b/src/lxc/commands_utils.c
index c4c7d5038aed288514d03ddccc5ccf168a54d997..4f9ee4a11b27938dbc5dd7d70569ba5f8527e5b6 100644 (file)
--- a/src/lxc/commands_utils.c
+++ b/src/lxc/commands_utils.c
@@ -24,6 +24,7 @@
 #include "memory_utils.h"
 #include "monitor.h"
 #include "state.h"
+#include "string_utils.h"
 #include "utils.h"
 
 lxc_log_define(commands_utils, lxc);
@@ -104,8 +105,8 @@ int lxc_make_abstract_socket_name(char *path, size_t pathlen,
                name = "";
 
        if (hashed_sock_name != NULL) {
-               ret = snprintf(offset, len, "lxc/%s/%s", hashed_sock_name, suffix);
-               if (ret < 0 || (size_t)ret >= len)
+               ret = strnprintf(offset, len, "lxc/%s/%s", hashed_sock_name, suffix);
+               if (ret < 0)
                        return log_error_errno(-1, errno, "Failed to create abstract socket name");
                return 0;
        }
@@ -116,6 +117,10 @@ int lxc_make_abstract_socket_name(char *path, size_t pathlen,
                        return log_error(-1, "Failed to allocate memory");
        }
 
+       /*
+        * Here we allow exceeding the buffer because we're falling back to
+        * hashing. So we're not using strnprintf() here.
+        */
        ret = snprintf(offset, len, "%s/%s/%s", lxcpath, name, suffix);
        if (ret < 0)
                return log_error_errno(-1, errno, "Failed to create abstract socket name");
@@ -127,13 +132,13 @@ int lxc_make_abstract_socket_name(char *path, size_t pathlen,
        if (ret >= len) {
                tmplen = strlen(name) + strlen(lxcpath) + 2;
                tmppath = must_realloc(NULL, tmplen);
-               ret = snprintf(tmppath, tmplen, "%s/%s", lxcpath, name);
-               if (ret < 0 || (size_t)ret >= tmplen)
+               ret = strnprintf(tmppath, tmplen, "%s/%s", lxcpath, name);
+               if (ret < 0)
                        return log_error_errno(-1, errno, "Failed to create abstract socket name");
 
                hash = fnv_64a_buf(tmppath, ret, FNV1A_64_INIT);
-               ret = snprintf(offset, len, "lxc/%016" PRIx64 "/%s", hash, suffix);
-               if (ret < 0 || (size_t)ret >= len)
+               ret = strnprintf(offset, len, "lxc/%016" PRIx64 "/%s", hash, suffix);
+               if (ret < 0)
                        return log_error_errno(-1, errno, "Failed to create abstract socket name");
        }