[PATCH v2] exfat: fix incorrect loading of i_blocks for large files

[PATCH v2] exfat: fix incorrect loading of i_blocks for large files

[Sungjong Seo]

When calculating i_blocks, there was a mistake that was masked with a
32-bit variable. So i_blocks for files larger than 4 GiB had incorrect
values. Mask with a 64-bit variable instead of 32-bit one.

Fixes: 5f2aa075070c ("exfat: add inode operations")
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Ganapathi Kamath <hgkamath@hotmail.com>
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
---
v2:
 - Fix maximum 75 characters warning from checkpatch.pl.

 fs/exfat/inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/exfat/inode.c b/fs/exfat/inode.c
index ca37d4344361..1c7aa1ea4724 100644
--- a/fs/exfat/inode.c
+++ b/fs/exfat/inode.c
@@ -604,7 +604,7 @@ static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
 	exfat_save_attr(inode, info->attr);
 
 	inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) &
-		~(sbi->cluster_size - 1)) >> inode->i_blkbits;
+		~((loff_t)sbi->cluster_size - 1)) >> inode->i_blkbits;
 	inode->i_mtime = info->mtime;
 	inode->i_ctime = info->mtime;
 	ei->i_crtime = info->crtime;
-- 
2.17.1

Re: [PATCH v2] exfat: fix incorrect loading of i_blocks for large files

[Namjae Jeon]

2021-10-19 15:14 GMT+09:00, Sungjong Seo <sj1557.seo@samsung.com>:
> When calculating i_blocks, there was a mistake that was masked with a
> 32-bit variable. So i_blocks for files larger than 4 GiB had incorrect
> values. Mask with a 64-bit variable instead of 32-bit one.
>
> Fixes: 5f2aa075070c ("exfat: add inode operations")
> Cc: stable@vger.kernel.org # v5.7+
> Reported-by: Ganapathi Kamath <hgkamath@hotmail.com>
> Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Applied, Thanks for your patch!