[PATCH AUTOSEL 5.10 1/6] efi: runtime: Fix potential overflow of soft-reserved region size

From: Sasha Levin
Date: Mon Feb 12 2024 - 20:05:28 EST


From: Andrew Bresticker <abrestic@xxxxxxxxxxxx>

[ Upstream commit de1034b38a346ef6be25fe8792f5d1e0684d5ff4 ]

md_size will have been narrowed if we have >= 4GB worth of pages in a
soft-reserved region.

Signed-off-by: Andrew Bresticker <abrestic@xxxxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/firmware/efi/arm-runtime.c | 2 +-
drivers/firmware/efi/riscv-runtime.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 3359ae2adf24..9054c2852580 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -107,7 +107,7 @@ static int __init arm_enable_runtime_services(void)
efi_memory_desc_t *md;

for_each_efi_memory_desc(md) {
- int md_size = md->num_pages << EFI_PAGE_SHIFT;
+ u64 md_size = md->num_pages << EFI_PAGE_SHIFT;
struct resource *res;

if (!(md->attribute & EFI_MEMORY_SP))
diff --git a/drivers/firmware/efi/riscv-runtime.c b/drivers/firmware/efi/riscv-runtime.c
index d28e715d2bcc..6711e64eb0b1 100644
--- a/drivers/firmware/efi/riscv-runtime.c
+++ b/drivers/firmware/efi/riscv-runtime.c
@@ -85,7 +85,7 @@ static int __init riscv_enable_runtime_services(void)
efi_memory_desc_t *md;

for_each_efi_memory_desc(md) {
- int md_size = md->num_pages << EFI_PAGE_SHIFT;
+ u64 md_size = md->num_pages << EFI_PAGE_SHIFT;
struct resource *res;

if (!(md->attribute & EFI_MEMORY_SP))
--
2.43.0