From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Darren Kenny <darren.kenny@oracle.com>
Date: Tue, 8 Dec 2020 22:17:04 +0000
Subject: [PATCH] zfs: Fix possible integer overflows
In all cases the problem is that the value being acted upon by
a left-shift is a 32-bit number which is then being used in the
context of a 64-bit number.
To avoid overflow we ensure that the number being shifted is 64-bit
before the shift is done.
Fixes: CID 73684, CID 73695, CID 73764
Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
grub-core/fs/zfs/zfs.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/grub-core/fs/zfs/zfs.c b/grub-core/fs/zfs/zfs.c
index 44d8bde6b33..0d8c08eec92 100644
--- a/grub-core/fs/zfs/zfs.c
+++ b/grub-core/fs/zfs/zfs.c
@@ -564,7 +564,7 @@ find_bestub (uberblock_phys_t * ub_array,
ubptr = (uberblock_phys_t *) ((grub_properly_aligned_t *) ub_array
+ ((i << ub_shift)
/ sizeof (grub_properly_aligned_t)));
- err = uberblock_verify (ubptr, offset, 1 << ub_shift);
+ err = uberblock_verify (ubptr, offset, (grub_size_t) 1 << ub_shift);
if (err)
{
grub_errno = GRUB_ERR_NONE;
@@ -1543,7 +1543,7 @@ read_device (grub_uint64_t offset, struct grub_zfs_device_desc *desc,
high = grub_divmod64 ((offset >> desc->ashift) + c,
desc->n_children, &devn);
- csize = bsize << desc->ashift;
+ csize = (grub_size_t) bsize << desc->ashift;
if (csize > len)
csize = len;
@@ -1635,8 +1635,8 @@ read_device (grub_uint64_t offset, struct grub_zfs_device_desc *desc,
while (len > 0)
{
- grub_size_t csize;
- csize = ((s / (desc->n_children - desc->nparity))
+ grub_size_t csize = s;
+ csize = ((csize / (desc->n_children - desc->nparity))
<< desc->ashift);
if (csize > len)
csize = len;