From ba2f48f70efcf4d82deafb2be327ed64b1f043a5 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Sun, 22 Aug 2010 07:10:12 +0300 Subject: UBIFS: mark unused key objects as invalid When scanning the flash, UBIFS builds a list of flash nodes of type 'struct ubifs_scan_node'. Each scanned node has a 'snod->key' field. This field is valid for most of the nodes, but invalid for some node type, e.g., truncation nodes. It is safer to explicitly initialize such keys to something invalid, rather than leaving them initialized to all zeros, which has key type of UBIFS_INO_KEY. This patch introduces new "fake" key type UBIFS_INVALID_KEY and initializes unused 'snod->key' objects to this type. It also adds debugging assertions in the TNC code to make sure no one ever tries to look these nodes up in the TNC. Signed-off-by: Artem Bityutskiy --- fs/ubifs/tnc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/ubifs/tnc.c') diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c index 2194915220e5..ad9cf0133622 100644 --- a/fs/ubifs/tnc.c +++ b/fs/ubifs/tnc.c @@ -1177,6 +1177,7 @@ int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key, unsigned long time = get_seconds(); dbg_tnc("search key %s", DBGKEY(key)); + ubifs_assert(key_type(c, key) < UBIFS_INVALID_KEY); znode = c->zroot.znode; if (unlikely(!znode)) { @@ -2966,7 +2967,7 @@ static struct ubifs_znode *right_znode(struct ubifs_info *c, * * This function searches an indexing node by its first key @key and its * address @lnum:@offs. It looks up the indexing tree by pulling all indexing - * nodes it traverses to TNC. This function is called fro indexing nodes which + * nodes it traverses to TNC. This function is called for indexing nodes which * were found on the media by scanning, for example when garbage-collecting or * when doing in-the-gaps commit. This means that the indexing node which is * looked for does not have to have exactly the same leftmost key @key, because @@ -2988,6 +2989,8 @@ static struct ubifs_znode *lookup_znode(struct ubifs_info *c, struct ubifs_znode *znode, *zn; int n, nn; + ubifs_assert(key_type(c, key) < UBIFS_INVALID_KEY); + /* * The arguments have probably been read off flash, so don't assume * they are valid. -- cgit v1.2.3-70-g09d2