ext3: fix chain verification in ext3_get_blocks()
Chain verification in ext3_get_blocks() has been hosed since it called
verify_chain(chain, NULL) which always returns success. As a result
readers could in theory race with truncate. On the other hand the race
probably cannot happen with the current locking scheme, since by the
time ext3_truncate() is called all the pages are already removed and
hence get_block() shouldn't be called on such pages...
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index b0248c6..253c2cd 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -820,7 +820,7 @@
while (count < maxblocks && count <= blocks_to_boundary) {
ext3_fsblk_t blk;
- if (!verify_chain(chain, partial)) {
+ if (!verify_chain(chain, chain + depth - 1)) {
/*
* Indirect block might be removed by
* truncate while we were reading it.