[PATCH 5.13 115/151] KVM: arm64: Fix off-by-one in range_is_memory

Greg Kroah-Hartman
2021-08-16T13:31:09Z

From: David Brazdil <dbrazdil@google.com>

[ Upstream commit facee1be7689f8cf573b9ffee6a5c28ee193615e ]

Hyp checks whether an address range only covers RAM by checking the
start/endpoints against a list of memblock_region structs. However,
the endpoint here is exclusive but internally is treated as inclusive.
Fix the off-by-one error that caused valid address ranges to be
rejected.

Cc: Quentin Perret <qperret@google.com>
Fixes: 90134ac9cabb6 ("KVM: arm64: Protect the .hyp sections from the host")
Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210728153232.1018911-2-dbrazdil@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 4b60c0056c04..fa1b77fe629d 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -190,7 +190,7 @@ static bool range_is_memory(u64 start, u64 end)
{
struct kvm_mem_range r1, r2;

- if (!find_mem_range(start, &r1) || !find_mem_range(end, &r2))
+ if (!find_mem_range(start, &r1) || !find_mem_range(end - 1, &r2))
return false;
if (r1.start != r2.start)
return false;
--
2.30.2