Re: [PATCH] f2fs: Cast expression type to unsigned long in __count_extent_cache()

[Chao Yu <chao@kernel.org>]

On 2024/3/5 16:09, Roman Smirnov wrote:
> Cast expression type to unsigned long in __count_extent_cache()
> to prevent integer overflow.
> 
> Found by Linux Verification Center (linuxtesting.org) with Svace.
> 
> Signed-off-by: Roman Smirnov <r.smirnov@omp.ru>
> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,

> ---
>   fs/f2fs/shrinker.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/shrinker.c b/fs/f2fs/shrinker.c
> index 83d6fb97dcae..bb86a06c5d5e 100644
> --- a/fs/f2fs/shrinker.c
> +++ b/fs/f2fs/shrinker.c
> @@ -33,7 +33,7 @@ static unsigned long __count_extent_cache(struct f2fs_sb_info *sbi,
>   {
>   	struct extent_tree_info *eti = &sbi->extent_tree[type];
>   
> -	return atomic_read(&eti->total_zombie_tree) +
> +	return (unsigned long)atomic_read(&eti->total_zombie_tree) +
>   				atomic_read(&eti->total_ext_node);
>   }
>