Acked-By: Kirill Korotaev <[EMAIL PROTECTED]>

> /proc/$PID/fd has r-x------ permissions, so if process does setuid(), it
> will not be able to access /proc/*/fd/. This breaks fstatat() emulation
> in glibc.
> 
> open("foo", O_RDONLY|O_DIRECTORY)       = 4
> setuid32(65534)                         = 0
> stat64("/proc/self/fd/4/bar", 0xbfafb298) = -1 EACCES (Permission denied)
> 
> Signed-off-by: Alexey Dobriyan <[EMAIL PROTECTED]>
> ---
> 
>  fs/proc/base.c |   16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> --- a/fs/proc/base.c
> +++ b/fs/proc/base.c
> @@ -1413,11 +1413,27 @@ static struct file_operations proc_fd_op
>       .readdir        = proc_readfd,
>  };
>  
> +static int proc_fd_permission(struct inode *inode, int mask, struct 
> nameidata *nd)
> +{
> +     struct task_struct *tsk;
> +     int rv;
> +
> +     rv = generic_permission(inode, mask, NULL);
> +     if (rv == 0)
> +             return 0;
> +     tsk = get_proc_task(inode);
> +     if (tsk == current)
> +             rv = 0;
> +     put_task_struct(tsk);
> +     return rv;
> +}
> +
>  /*
>   * proc directories can do almost nothing..
>   */
>  static struct inode_operations proc_fd_inode_operations = {
>       .lookup         = proc_lookupfd,
> +     .permission     = proc_fd_permission,
>       .setattr        = proc_setattr,
>  };
>  
> 
> _______________________________________________
> Devel mailing list
> [email protected]
> https://openvz.org/mailman/listinfo/devel
> 

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to