On 02/11/2013 06:09 PM, Peter Schiffer wrote:
> mkdir(2) function returns EROFS error even when the path already exists on the
> read only file system, so it is impossible to determine whether the path
> already
> exists on this kind of fs only be return code from the mkdir(2). To make
> cg_mkdir_p() compatible with the ro fs, the function checks whether the path
> exists with stat(2) before trying to create it.
>
> Signed-off-by: Peter Schiffer <pschi...@redhat.com>
> ---
> 0 files changed
>
> diff --git a/src/api.c b/src/api.c
> index 11cd1b4..4acdc30 100644
> --- a/src/api.c
> +++ b/src/api.c
> @@ -1271,6 +1271,7 @@ int cg_mkdir_p(const char *path)
> int i = 0;
> char pos;
> int ret = 0;
> + struct stat st;
>
> real_path = strdup(path);
> if (!real_path) {
> @@ -1287,6 +1288,10 @@ int cg_mkdir_p(const char *path)
> i++;
> pos = real_path[i];
> real_path[i] = '\0'; /* Temporarily overwrite "/" */
> + if (stat(real_path, &st) == 0) { /* Continue if
> dir exists */
> + real_path[i] = pos;
> + continue;
> + }
> ret = mkdir(real_path, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
> real_path[i] = pos;
> if (ret) {
This is classical TOCTTOU. While it does not have any security
implications, it would be better to mkdir() and only if it fails, then
check if the directory was already there.
Jan
------------------------------------------------------------------------------
Free Next-Gen Firewall Hardware Offer
Buy your Sophos next-gen firewall before the end March 2013
and get the hardware for free! Learn more.
http://p.sf.net/sfu/sophos-d2d-feb
_______________________________________________
Libcg-devel mailing list
Libcg-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/libcg-devel
