Commit bdf6cbf1 authored by Al Viro's avatar Al Viro
Browse files

link_path_walk: final preparations to killing recursion 



reduce the number of returns in there - turn all places
where it returns zero into goto OK and places where it
returns non-zero into goto Err.  The only non-trivial
detail is that all breaks in the loop are guaranteed
to be with non-zero err.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent bb8603f8

fs/namei.c

+11 −7
Original line number Diff line number Diff line
@@ -1716,7 +1716,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
	while (*name=='/')

		name++;

	if (!*name)

		return 0;

		goto OK;



	/* At this point we know we have a real path component. */

	for(;;) {
@@ -1759,7 +1759,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) 


		name += hashlen_len(hash_len);

		if (!*name)

			return 0;

			goto OK;

		/*

		 * If it wasn't NUL, we know it was '/'. Skip that

		 * slash, and continue until no more slashes.
@@ -1768,12 +1768,12 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
			name++;

		} while (unlikely(*name == '/'));

		if (!*name)

			return 0;

			goto OK;



		err = walk_component(nd, LOOKUP_FOLLOW);

Walked:

		if (err < 0)

			return err;

			goto Err;



		if (err) {

			struct path link;
@@ -1783,7 +1783,8 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
			if (unlikely(current->link_count >= MAX_NESTED_LINKS)) {

				path_put_conditional(&nd->link, nd);

				path_put(&nd->path);

				return -ELOOP;

				err = -ELOOP;

				goto Err;

			}

			BUG_ON(nd->depth >= MAX_NESTED_LINKS);
@@ -1797,7 +1798,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
				err = PTR_ERR(s);

				current->link_count--;

				nd->depth--;

				return err;

				goto Err;

			}

			err = 0;

			if (unlikely(!s)) {
@@ -1820,7 +1821,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
					put_link(nd, &link, cookie);

					current->link_count--;

					nd->depth--;

					return err;

					goto Err;

				} else {

					err = walk_component(nd, LOOKUP_FOLLOW);

					put_link(nd, &link, cookie);
@@ -1836,7 +1837,10 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
		}

	}

	terminate_walk(nd);

Err:

	return err;

OK:

	return 0;

}



static int path_init(int dfd, const struct filename *name, unsigned int flags,