From 302c12ff5714bc455949117c1c9548ccb324d55b Mon Sep 17 00:00:00 2001 From: Darren Kenny 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 Reviewed-by: Daniel Kiper Signed-off-by: Stefan Sørensen --- 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 9087a72..b078ccc 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; -- 2.14.2