Terminate readlink string

The function readlink does not nul terminate its result string.  safe_readlink
is a wrapper for readlinkat, which has the same behaviour.
* src/util.c (copy_file): Therefore, explicitly set '\0' and reserve one byte
for it.  (agruen: Reserve PATH_MAX + 1 bytes instead of only reading PATH_MAX -
1 characters.)

1 files changed, 4 insertions, 2 deletions

diff --git a/src/util.c b/src/util.c
index 82a7e37..ee88c13 100644
--- a/src/util.c
+++ b/src/util.c
@@ -610,10 +610,12 @@ copy_file (char const *from, char const *to, struct stat *tost,
 
   if (S_ISLNK (mode))
     {
-      char *buffer = xmalloc (PATH_MAX);
+      char *buffer = xmalloc (PATH_MAX + 1);
+      ssize_t r;
 
-      if (safe_readlink (from, buffer, PATH_MAX) < 0)
+      if ((r = safe_readlink (from, buffer, PATH_MAX)) < 0)
 	pfatal ("Can't read %s %s", "symbolic link", from);
+      buffer[r] = '\0';
       if (safe_symlink (buffer, to) != 0)
 	pfatal ("Can't create %s %s", "symbolic link", to);
       if (tost && safe_lstat (to, tost) != 0)