Commit 5a202bcd authored by Al Viro's avatar Al Viro
Browse files

sanitize pathname component hash calculation 



Lift it to lookup_one_len() and link_path_walk() resp. into the
same place where we calculated default hash function of the same
name.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 6a96ba54

fs/namei.c

+19 −23
Original line number Diff line number Diff line
@@ -1216,16 +1216,6 @@ static int do_lookup(struct nameidata *nd, struct qstr *name, 
	struct inode *dir;

	int err;



	/*

	 * See if the low-level filesystem might want

	 * to use its own hash..

	 */

	if (unlikely(parent->d_flags & DCACHE_OP_HASH)) {

		err = parent->d_op->d_hash(parent, nd->inode, name);

		if (err < 0)

			return err;

	}



	/*

	 * Rename seqlock is not required here because in the off chance

	 * of a false negative due to a concurrent rename, we're going to
@@ -1414,8 +1404,16 @@ static int link_path_walk(const char *name, struct nameidata *nd) 
			case 1:

				type = LAST_DOT;

		}

		if (likely(type == LAST_NORM))

		if (likely(type == LAST_NORM)) {

			struct dentry *parent = nd->path.dentry;

			nd->flags &= ~LOOKUP_JUMPED;

			if (unlikely(parent->d_flags & DCACHE_OP_HASH)) {

				err = parent->d_op->d_hash(parent, nd->inode,

							   &this);

				if (err < 0)

					break;

			}

		}



		/* remove trailing slashes? */

		if (!c)
@@ -1722,17 +1720,6 @@ static struct dentry *__lookup_hash(struct qstr *name, 
	if (err)

		return ERR_PTR(err);



	/*

	 * See if the low-level filesystem might want

	 * to use its own hash..

	 */

	if (base->d_flags & DCACHE_OP_HASH) {

		err = base->d_op->d_hash(base, inode, name);

		dentry = ERR_PTR(err);

		if (err < 0)

			goto out;

	}



	/*

	 * Don't bother with __d_lookup: callers are for creat as

	 * well as unlink, so a lot of the time it would cost
@@ -1745,7 +1732,7 @@ static struct dentry *__lookup_hash(struct qstr *name, 


	if (!dentry)

		dentry = d_alloc_and_lookup(base, name, nd);

out:



	return dentry;

}
@@ -1791,6 +1778,15 @@ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len) 
		hash = partial_name_hash(c, hash);

	}

	this.hash = end_name_hash(hash);

	/*

	 * See if the low-level filesystem might want

	 * to use its own hash..

	 */

	if (base->d_flags & DCACHE_OP_HASH) {

		int err = base->d_op->d_hash(base, base->d_inode, &this);

		if (err < 0)

			return ERR_PTR(err);

	}



	return __lookup_hash(&this, base, NULL);

}