[PATCH 1/2] KVM: arm64: Fix off-by-one in range_is_memory

From: David Brazdil
Date: Wed Jul 28 2021 - 11:32:47 EST


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@xxxxxxxxxx>
Fixes: 90134ac9cabb6 ("KVM: arm64: Protect the .hyp sections from the host")
Signed-off-by: David Brazdil <dbrazdil@xxxxxxxxxx>
---
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 d938ce95d3bd..a6ce991b1467 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -193,7 +193,7 @@ 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;
--
2.32.0.432.gabb21c7263-goog