Re: [PATCH] O_DIRECTORY|O_CREAT handling

[Andrew Pimlott]

On Sun, Dec 21, 2003 at 11:51:10AM +0100, Willy Tarreau wrote:
>   base_dir="/tmp/tmpdir"; 
>   do {
>      rnd=random();
>      sprintf(dir, "%s%d", base_dir, rnd);
>   } while (!mkdir(dir, 0700);
>   /* now I'm guaranteed that I'm the first to get this dir, */
>   /* and only my UID can work in it */
>   chdir(dir);
>   
> So the only race would be someone working with the same UID (or root) removing
> the directory and replacing it with another one (or a symlink or anything)
> between mkdir() and chdir().

If /tmp isn't sticky, anyone can do this.  I think this is the
scenario Ulrich was referring to.

Andrew
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