Ocfs2 devel - Feb 2015 - [PATCH 1/4 V2] ocfs2: use retval instead of status for checking error

The use of 'status' in __ocfs2_add_entry() can return wrong
status when some functions are failed.

If ocfs2_journal_access_db() in __ocfs2_add_entry() is failed,
that status is saved to 'status' but return variable is 'retval'
which is saved 'success' status. In case of this,  __ocfs2_add_entry()
is failed but can be returned as 'success'.

So replace 'status' with 'retval'.

Signed-off-by: Daeseok Youn <daeseok.youn at gmail.com>
---
V2 : update changelog

 fs/ocfs2/dir.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index b08050b..1478a50 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -1617,7 +1617,7 @@ int __ocfs2_add_entry(handle_t *handle,
 	struct ocfs2_dir_entry *de, *de1;
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_fe_bh->b_data;
 	struct super_block *sb = dir->i_sb;
-	int retval, status;
+	int retval;
 	unsigned int size = sb->s_blocksize;
 	struct buffer_head *insert_bh = lookup->dl_leaf_bh;
 	char *data_start = insert_bh->b_data;
@@ -1695,22 +1695,22 @@ int __ocfs2_add_entry(handle_t *handle,
 			}
 
 			if (insert_bh == parent_fe_bh)
-				status = ocfs2_journal_access_di(handle,
+				retval = ocfs2_journal_access_di(handle,
 								 INODE_CACHE(dir),
 								 insert_bh,
 								 OCFS2_JOURNAL_ACCESS_WRITE);
 			else {
-				status = ocfs2_journal_access_db(handle,
+				retval = ocfs2_journal_access_db(handle,
 								 INODE_CACHE(dir),
 								 insert_bh,
 					      OCFS2_JOURNAL_ACCESS_WRITE);
 
 				if (ocfs2_dir_indexed(dir)) {
-					status = ocfs2_dx_dir_insert(dir,
+					retval = ocfs2_dx_dir_insert(dir,
 								handle,
 								lookup);
-					if (status) {
-						mlog_errno(status);
+					if (retval) {
+						mlog_errno(retval);
 						goto bail;
 					}
 				}
-- 
1.7.1

Am 28.02.2015 um 00:48 schrieb Daeseok Youn:
> The use of 'status' in __ocfs2_add_entry() can return wrong
> status when some functions are failed.
> 
> If ocfs2_journal_access_db() in __ocfs2_add_entry() is failed,
> that status is saved to 'status' but return variable is
'retval'
> which is saved 'success' status. In case of this, 
__ocfs2_add_entry()
> is failed but can be returned as 'success'.
> 
> So replace 'status' with 'retval'.
As this patch is untested and the issue is theoretical I'm nervous.
But the final decision is up to ocfs2 maintainers.

Thanks,
//richard

Hi,

This patch have been pending for 2 weeks.
Do I need to check other things?

please, check for me.

Thanks!

regards,
Daeseok Youn

2015-02-28 8:48 GMT+09:00 Daeseok Youn <daeseok.youn at
gmail.com>:
> The use of 'status' in __ocfs2_add_entry() can return wrong
> status when some functions are failed.
>
> If ocfs2_journal_access_db() in __ocfs2_add_entry() is failed,
> that status is saved to 'status' but return variable is
'retval'
> which is saved 'success' status. In case of this, 
__ocfs2_add_entry()
> is failed but can be returned as 'success'.
>
> So replace 'status' with 'retval'.
>
> Signed-off-by: Daeseok Youn <daeseok.youn at gmail.com>
> ---
> V2 : update changelog
>
>  fs/ocfs2/dir.c |   12 ++++++------
>  1 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
> index b08050b..1478a50 100644
> --- a/fs/ocfs2/dir.c
> +++ b/fs/ocfs2/dir.c
> @@ -1617,7 +1617,7 @@ int __ocfs2_add_entry(handle_t *handle,
>         struct ocfs2_dir_entry *de, *de1;
>         struct ocfs2_dinode *di = (struct ocfs2_dinode
*)parent_fe_bh->b_data;
>         struct super_block *sb = dir->i_sb;
> -       int retval, status;
> +       int retval;
>         unsigned int size = sb->s_blocksize;
>         struct buffer_head *insert_bh = lookup->dl_leaf_bh;
>         char *data_start = insert_bh->b_data;
> @@ -1695,22 +1695,22 @@ int __ocfs2_add_entry(handle_t *handle,
>                         }
>
>                         if (insert_bh == parent_fe_bh)
> -                               status = ocfs2_journal_access_di(handle,
> +                               retval = ocfs2_journal_access_di(handle,
>                                                                 
INODE_CACHE(dir),
>                                                                  insert_bh,
>                                                                 
OCFS2_JOURNAL_ACCESS_WRITE);
>                         else {
> -                               status = ocfs2_journal_access_db(handle,
> +                               retval = ocfs2_journal_access_db(handle,
>                                                                 
INODE_CACHE(dir),
>                                                                  insert_bh,
>                                               OCFS2_JOURNAL_ACCESS_WRITE);
>
>                                 if (ocfs2_dir_indexed(dir)) {
> -                                       status = ocfs2_dx_dir_insert(dir,
> +                                       retval = ocfs2_dx_dir_insert(dir,
>                                                                 handle,
>                                                                 lookup);
> -                                       if (status) {
> -                                               mlog_errno(status);
> +                                       if (retval) {
> +                                               mlog_errno(retval);
>                                                 goto bail;
>                                         }
>                                 }
> --
> 1.7.1
>

Looks good to me.

On 2015/2/28 7:48, Daeseok Youn wrote:
> The use of 'status' in __ocfs2_add_entry() can return wrong
> status when some functions are failed.
> 
> If ocfs2_journal_access_db() in __ocfs2_add_entry() is failed,
> that status is saved to 'status' but return variable is
'retval'
> which is saved 'success' status. In case of this, 
__ocfs2_add_entry()
> is failed but can be returned as 'success'.
> 
> So replace 'status' with 'retval'.
> 
> Signed-off-by: Daeseok Youn <daeseok.youn at gmail.com>
Reviewed-by: Joseph Qi <joseph.qi at huawei.com>
> ---
> V2 : update changelog
> 
>  fs/ocfs2/dir.c |   12 ++++++------
>  1 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
> index b08050b..1478a50 100644
> --- a/fs/ocfs2/dir.c
> +++ b/fs/ocfs2/dir.c
> @@ -1617,7 +1617,7 @@ int __ocfs2_add_entry(handle_t *handle,
>  	struct ocfs2_dir_entry *de, *de1;
>  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_fe_bh->b_data;
>  	struct super_block *sb = dir->i_sb;
> -	int retval, status;
> +	int retval;
>  	unsigned int size = sb->s_blocksize;
>  	struct buffer_head *insert_bh = lookup->dl_leaf_bh;
>  	char *data_start = insert_bh->b_data;
> @@ -1695,22 +1695,22 @@ int __ocfs2_add_entry(handle_t *handle,
>  			}
>  
>  			if (insert_bh == parent_fe_bh)
> -				status = ocfs2_journal_access_di(handle,
> +				retval = ocfs2_journal_access_di(handle,
>  								 INODE_CACHE(dir),
>  								 insert_bh,
>  								 OCFS2_JOURNAL_ACCESS_WRITE);
>  			else {
> -				status = ocfs2_journal_access_db(handle,
> +				retval = ocfs2_journal_access_db(handle,
>  								 INODE_CACHE(dir),
>  								 insert_bh,
>  					      OCFS2_JOURNAL_ACCESS_WRITE);
>  
>  				if (ocfs2_dir_indexed(dir)) {
> -					status = ocfs2_dx_dir_insert(dir,
> +					retval = ocfs2_dx_dir_insert(dir,
>  								handle,
>  								lookup);
> -					if (status) {
> -						mlog_errno(status);
> +					if (retval) {
> +						mlog_errno(retval);
>  						goto bail;
>  					}
>  				}
>

On Sat, 28 Feb 2015 08:48:40 +0900 Daeseok Youn <daeseok.youn at
gmail.com> wrote:
> The use of 'status' in __ocfs2_add_entry() can return wrong
> status when some functions are failed.
> 
> If ocfs2_journal_access_db() in __ocfs2_add_entry() is failed,
> that status is saved to 'status' but return variable is
'retval'
> which is saved 'success' status. In case of this, 
__ocfs2_add_entry()
> is failed but can be returned as 'success'.
> 
> So replace 'status' with 'retval'.
> 
> -						mlog_errno(status);
> +					if (retval) {
> +						mlog_errno(retval);
>  						goto bail;
and

bail:
	if (retval)
		mlog_errno(retval);

	return retval;
}

so we'll clearly log the same error twice.