From: Mingming Cao <[email protected]>
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 <[email protected]>
Cc: Yan Zheng <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
fs/ext4/extents.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -1445,7 +1445,7 @@ int ext4_ext_walk_space(struct inode *in
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);
--