Commit c99658fe authored Dec 24, 2009 by Al Viro

bail out with ELOOP earlier in do_link loop



If we'd passed through 32 trailing symlinks already, there's
no sense following the 33rd - we'll bail out anyway.  Better
bugger off earlier.

It *does* change behaviour, after a fashion - if the 33rd happens
to be a procfs-style symlink, original code *would* allow it.
This one will not.  Cry me a river if that hurts you.  Please, do.
And post a video of that, while you are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

parent a1e28038

fs/namei.c

+1 −6

Original line number	Diff line number	Diff line
		@@ -1873,7 +1873,7 @@ exit_parent:

		do_link:
		error = -ELOOP;
		if (flag & O_NOFOLLOW)
		if ((flag & O_NOFOLLOW) \|\| count++ == 32)
		goto exit_dput;
		/*
		* This is subtle. Instead of calling do_follow_link() we do the
		@@ -1915,11 +1915,6 @@ do_link:
		__putname(nd.last.name);
		goto exit;
		}
		error = -ELOOP;
		if (count++==32) {
		__putname(nd.last.name);
		goto exit;
		}
		filp = do_last(&nd, &path, open_flag, flag, acc_mode, mode,
		pathname, &is_link);
		__putname(nd.last.name);