From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Subject: fs/ufs: avoid potential u32 multiplication overflow
The 64 bit ino is being compared to the product of two u32 values,
however, the multiplication is being performed using a 32 bit multiply so
there is a potential of an overflow. To be fully safe, cast uspi->s_ncg
to a u64 to ensure a 64 bit multiplication occurs to avoid any chance of
overflow.
Addresses-Coverity: ("Unintentional integer overflow")
Link: http://lkml.kernel.org/r/20200715170355.1081713-1-colin.king@xxxxxxxxxxxxx
Fixes: f3e2a520f5fb ("ufs: NFS support")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Cc: Evgeniy Dushistov <dushistov@xxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ufs/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/ufs/super.c~fs-ufs-avoid-potential-u32-multiplication-overflow
+++ a/fs/ufs/super.c
@@ -101,7 +101,7 @@ static struct inode *ufs_nfs_get_inode(s
struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
struct inode *inode;
- if (ino < UFS_ROOTINO || ino > uspi->s_ncg * uspi->s_ipg)
+ if (ino < UFS_ROOTINO || ino > (u64)uspi->s_ncg * uspi->s_ipg)
return ERR_PTR(-ESTALE);
inode = ufs_iget(sb, ino);
_
