[ Upstream commit 43946b70494beefe40ec1b2ba4744c0f294d7736 ]
An overflow issue can occur while calculating sector in
exfat_cluster_to_sector(). It needs to cast clus's type to sector_t
before left shifting.
Fixes: 1acf1a564b60 ("exfat: add in-memory and on-disk structures and headers")
Cc: stable@xxxxxxxxxxxxxxx # v5.7
Reviewed-by: Sungjong Seo <sj1557.seo@xxxxxxxxxxx>
Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
---
fs/exfat/exfat_fs.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index d865050fa6cd..99e9baf2d31d 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -375,7 +375,7 @@ static inline bool exfat_is_last_sector_in_cluster(struct exfat_sb_info *sbi,
static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info *sbi,
unsigned int clus)
{
- return ((clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) +
+ return ((sector_t)(clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) +
sbi->data_start_sector;
}
--
2.17.1
