Re: [PATCH 1/4] f2fs: fix to do cast in F2FS_{BLK_TO_BYTES, BTYES_TO_BLK} to avoid overflow

[Jaegeuk Kim <jaegeuk@kernel.org>]

I applied this with the below change to avoid build failure.

--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3336,7 +3336,7 @@ loff_t max_file_blocks(struct inode *inode)
         * fit within U32_MAX + 1 data units.
         */

-       result = min(result, F2FS_BYTES_TO_BLK(((loff_t)U32_MAX + 1) * 4096));
+       result = umin(result, F2FS_BYTES_TO_BLK(((loff_t)U32_MAX + 1) * 4096));

        return result;
 }

On 11/08, Chao Yu wrote:
> It missed to cast variable to unsigned long long type before
> bit shift, which will cause overflow, fix it.
> 
> Fixes: f7ef9b83b583 ("f2fs: introduce macros to convert bytes and blocks in f2fs")
> Signed-off-by: Chao Yu <chao@kernel.org>
> ---
>  include/linux/f2fs_fs.h | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
> index b0b821edfd97..3b2ad444c002 100644
> --- a/include/linux/f2fs_fs.h
> +++ b/include/linux/f2fs_fs.h
> @@ -24,10 +24,10 @@
>  #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
>  #define COMPRESS_ADDR		((block_t)-2)	/* used as compressed data flag */
>  
> -#define F2FS_BYTES_TO_BLK(bytes)	((bytes) >> F2FS_BLKSIZE_BITS)
> -#define F2FS_BLK_TO_BYTES(blk)		((blk) << F2FS_BLKSIZE_BITS)
> +#define F2FS_BYTES_TO_BLK(bytes)	((unsigned long long)(bytes) >> F2FS_BLKSIZE_BITS)
> +#define F2FS_BLK_TO_BYTES(blk)		((unsigned long long)(blk) << F2FS_BLKSIZE_BITS)
>  #define F2FS_BLK_END_BYTES(blk)		(F2FS_BLK_TO_BYTES(blk + 1) - 1)
> -#define F2FS_BLK_ALIGN(x)			(F2FS_BYTES_TO_BLK((x) + F2FS_BLKSIZE - 1))
> +#define F2FS_BLK_ALIGN(x)		(F2FS_BYTES_TO_BLK((x) + F2FS_BLKSIZE - 1))
>  
>  /* 0, 1(node nid), 2(meta nid) are reserved node id */
>  #define F2FS_RESERVED_NODE_NUM		3
> -- 
> 2.40.1