[PATCH] Btrfs: fix wrong list access on the failure of reading out checksum

[PATCH] Btrfs: fix wrong list access on the failure of reading out checksum

[Miao Xie]

If we failed to reading out the checksum, we would free all the checksums
in the list. But the current code accessed the list head, not the entry
in the list. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
---
 fs/btrfs/file-item.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 783a943..c26b58f 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -413,7 +413,8 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
 	ret = 0;
 fail:
 	while (ret < 0 && !list_empty(&tmplist)) {
-		sums = list_entry(&tmplist, struct btrfs_ordered_sum, list);
+		sums = list_first_entry(&tmplist, struct btrfs_ordered_sum,
+					list);
 		list_del(&sums->list);
 		kfree(sums);
 	}
-- 
1.9.3

Re: [PATCH] Btrfs: fix wrong list access on the failure of reading out checksum

[Miao Xie]

Please ignore this patch, Chris has fixed this problem.

Thanks
Miao

On Mon, 1 Dec 2014 18:04:13 +0800, Miao Xie wrote:
> If we failed to reading out the checksum, we would free all the checksums
> in the list. But the current code accessed the list head, not the entry
> in the list. Fix it.
> 
> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
> ---
>  fs/btrfs/file-item.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
> index 783a943..c26b58f 100644
> --- a/fs/btrfs/file-item.c
> +++ b/fs/btrfs/file-item.c
> @@ -413,7 +413,8 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
>  	ret = 0;
>  fail:
>  	while (ret < 0 && !list_empty(&tmplist)) {
> -		sums = list_entry(&tmplist, struct btrfs_ordered_sum, list);
> +		sums = list_first_entry(&tmplist, struct btrfs_ordered_sum,
> +					list);
>  		list_del(&sums->list);
>  		kfree(sums);
>  	}
>