From: Mostafa Saleh <smostafa@google.com>
Date: Wed, 3 Jun 2026 11:05:21 +0000 (+0000)
Subject: drivers/virt: pkvm: Fix end calculation in mmio_guard_ioremap_hook()
X-Git-Tag: v7.2-rc5~23^2~5
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=62c740f823a8e47ffe56e45a7472c27cf988e2f6;p=thirdparty%2Flinux.git

drivers/virt: pkvm: Fix end calculation in mmio_guard_ioremap_hook()

Sashiko (locally) reports a logical issues in mmio_guard_ioremap_hook()

mmio_guard_ioremap_hook() attempts to handle unaligned addresses and
sizes. However, aligning the start address before adding the size, might
shift the end to the page before.

Fixes: 0f1269495800 ("drivers/virt: pkvm: Intercept ioremap using pKVM MMIO_GUARD hypercall")
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
---

diff --git a/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c b/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c
index 4230b817a80b..d66291def0f4 100644
--- a/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c
+++ b/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c
@@ -82,8 +82,8 @@ static int mmio_guard_ioremap_hook(phys_addr_t phys, size_t size,
 	if (protval != PROT_DEVICE_nGnRE && protval != PROT_DEVICE_nGnRnE)
 		return 0;
 
+	end = PAGE_ALIGN(phys + size);
 	phys = PAGE_ALIGN_DOWN(phys);
-	end = phys + PAGE_ALIGN(size);
 
 	while (phys < end) {
 		const int func_id = ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_FUNC_ID;