Re: [RFC/PATCH] ext4: Fix the memory leak and buffer head leak with respect to ext4_ext_path

[Mingming Cao <cmm@us.ibm.com>]

Added in ext4 patch queue,
Thanks

On Thu, 2008-02-14 at 16:00 +0530, Aneesh Kumar K.V wrote:
> The path variable returned via ext4_ext_find_extent is a kmalloc variable
> and need to be freeded. It also contain refrences to buffer_head which need
> to be dropped.
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> ---
>  fs/ext4/extents.c               |    6 +++---
>  fs/ext4/migrate.c               |    5 +++++
>  include/linux/ext4_fs_extents.h |    1 +
>  3 files changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
> index e856f66..995ac16 100644
> --- a/fs/ext4/extents.c
> +++ b/fs/ext4/extents.c
> @@ -349,7 +349,7 @@ static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
>  #define ext4_ext_show_leaf(inode,path)
>  #endif
> 
> -static void ext4_ext_drop_refs(struct ext4_ext_path *path)
> +void ext4_ext_drop_refs(struct ext4_ext_path *path)
>  {
>  	int depth = path->p_depth;
>  	int i;
> @@ -2200,10 +2200,10 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
>  		newdepth = ext_depth(inode);
>  		if (newdepth != depth) {
>  			depth = newdepth;
> -			path = ext4_ext_find_extent(inode, iblock, NULL);
> +			ext4_ext_drop_refs(path);
> +			path = ext4_ext_find_extent(inode, iblock, path);
>  			if (IS_ERR(path)) {
>  				err = PTR_ERR(path);
> -				path = NULL;
>  				goto out;
>  			}
>  			eh = path[depth].p_hdr;
> diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
> index 8c6c685..5c1e27d 100644
> --- a/fs/ext4/migrate.c
> +++ b/fs/ext4/migrate.c
> @@ -43,6 +43,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
> 
>  	if (IS_ERR(path)) {
>  		retval = PTR_ERR(path);
> +		path = NULL;
>  		goto err_out;
>  	}
> 
> @@ -74,6 +75,10 @@ static int finish_range(handle_t *handle, struct inode *inode,
>  	}
>  	retval = ext4_ext_insert_extent(handle, inode, path, &newext);
>  err_out:
> +	if (path) {
> +		ext4_ext_drop_refs(path);
> +		kfree(path);
> +	}
>  	lb->first_pblock = 0;
>  	return retval;
>  }
> diff --git a/include/linux/ext4_fs_extents.h b/include/linux/ext4_fs_extents.h
> index 697da4b..1285c58 100644
> --- a/include/linux/ext4_fs_extents.h
> +++ b/include/linux/ext4_fs_extents.h
> @@ -227,5 +227,6 @@ extern int ext4_ext_search_left(struct inode *, struct ext4_ext_path *,
>  						ext4_lblk_t *, ext4_fsblk_t *);
>  extern int ext4_ext_search_right(struct inode *, struct ext4_ext_path *,
>  						ext4_lblk_t *, ext4_fsblk_t *);
> +extern void ext4_ext_drop_refs(struct ext4_ext_path *);
>  #endif /* _LINUX_EXT4_EXTENTS */
>