2019-10-22 09:32:17

by Chengguang Xu

Subject: [PATCH] ext2: don't set count in the case of failure

In the case of failure, the num is still initialized value 0
so we should not set it to *count because it will bring
unexpected side effect to the caller.

Signed-off-by: Chengguang Xu <[email protected]>
---
fs/ext2/balloc.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
index 18e75adcd2f6..cc516c7b7974 100644
--- a/fs/ext2/balloc.c
+++ b/fs/ext2/balloc.c
@@ -736,7 +736,6 @@ ext2_try_to_allocate(struct super_block *sb, int group,
*count = num;
return grp_goal - num;
fail_access:
- *count = num;
return -1;
}

--
2.20.1

2019-10-25 20:14:27

by Jan Kara

Subject: Re: [PATCH] ext2: don't set count in the case of failure

On Tue 22-10-19 17:27:20, Chengguang Xu wrote:
> In the case of failure, the num is still initialized value 0
> so we should not set it to *count because it will bring
> unexpected side effect to the caller.
>
> Signed-off-by: Chengguang Xu <[email protected]>

Looks good to me but please ellaborate a bit in the changelog what are
visible effects of this bug. Thanks!

Honza

> ---
> fs/ext2/balloc.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
> index 18e75adcd2f6..cc516c7b7974 100644
> --- a/fs/ext2/balloc.c
> +++ b/fs/ext2/balloc.c
> @@ -736,7 +736,6 @@ ext2_try_to_allocate(struct super_block *sb, int group,
> *count = num;
> return grp_goal - num;
> fail_access:
> - *count = num;
> return -1;
> }
>
> --
> 2.20.1
>
>
>
--
Jan Kara <[email protected]>
SUSE Labs, CR