Re: [PATCH] fs: hardlink creation restrictions
From: Marcin Slusarz <hidden>
Date: 2012-02-18 20:56:26
Also in:
lkml
On Sat, Feb 18, 2012 at 11:38:57AM -0800, Kees Cook wrote:
quoted hunk ↗ jump to hunk
@@ -3052,6 +3119,9 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, error = mnt_want_write(new_path.mnt); if (error) goto out_dput; + error = may_linkat(&old_path); + if (error) + goto out_dput; error = security_path_link(old_path.dentry, &new_path, new_dentry); if (error) goto out_drop_write;
You should give up write access after check failure (i.e. goto out_drop_write). Marcin