From: Willy Tarreau Subject: [2.6.20.17 review 26/58] "ext4_ext_put_in_cache" uses __u32 to receive physical block number Date: Wed, 22 Aug 2007 11:39:10 +0200 Message-ID: <20070822084011.%N@1wt.eu> References: <20070822083844.%N@1wt.eu> Cc: Mingming Cao , Yan Zheng , , Andrew Morton , Greg Kroah-Hartman , Willy Tarreau To: linux-kernel@vger.kernel.org, stable@kernel.org Return-path: Content-Disposition: inline; filename=0026-ext4_ext_put_in_cache-uses-__u32-to-receive-physic.patch Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Yan Zheng wrote: > I think I found a bug in ext4/extents.c, "ext4_ext_put_in_cache" uses > "__u32" to receive physical block number. "ext4_ext_put_in_cache" is > used in "ext4_ext_get_blocks", it sets ext4 inode's extent cache > according most recently tree lookup (higher 16 bits of saved physical > block number are always zero). when serving a mapping request, > "ext4_ext_get_blocks" first check whether the logical block is in > inode's extent cache. if the logical block is in the cache and the > cached region isn't a gap, "ext4_ext_get_blocks" gets physical block > number by using cached region's physical block number and offset in > the cached region. as described above, "ext4_ext_get_blocks" may > return wrong result when there are physical block numbers bigger than > 0xffffffff. > You are right. Thanks for reporting this! Signed-off-by: Mingming Cao Cc: Yan Zheng Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Willy Tarreau --- fs/ext4/extents.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index dc2724f..14b0b49 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -1397,7 +1397,7 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block, static void ext4_ext_put_in_cache(struct inode *inode, __u32 block, - __u32 len, __u32 start, int type) + __u32 len, ext4_fsblk_t start, int type) { struct ext4_ext_cache *cex; BUG_ON(len == 0); -- 1.5.2.5 --