From 97f76d3d197f201ac8a8a3ced5b8fef81568e50e Mon Sep 17 00:00:00 2001 From: Nikanth Karthikesan Date: Thu, 2 Apr 2009 16:56:46 -0700 Subject: [PATCH] vfs: check bh->b_blocknr only if BH_Mapped is set Check bh->b_blocknr only if BH_Mapped is set. akpm: I doubt if b_blocknr is ever uninitialised here, but it could conceivably cause a problem if we're doing a lookup for block zero. Signed-off-by: Nikanth Karthikesan Cc: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index f5f8b15a6e40..2963858f0f31 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -199,13 +199,13 @@ __find_get_block_slow(struct block_device *bdev, sector_t block) head = page_buffers(page); bh = head; do { - if (bh->b_blocknr == block) { + if (!buffer_mapped(bh)) + all_mapped = 0; + else if (bh->b_blocknr == block) { ret = bh; get_bh(bh); goto out_unlock; } - if (!buffer_mapped(bh)) - all_mapped = 0; bh = bh->b_this_page; } while (bh != head); -- 2.20.1