From: Heinrich Schuchardt <heinrich.schuchardt@xxxxxxxxxxxxx>
[ Upstream commit 630f972d76d6460235e84e1aa034ee06f9c8c3a9 ]
If EFI pages are marked as read-only,
we should remove the _PAGE_WRITE flag.
The current code overwrites an unused value.
Fixes: b91540d52a08b ("RISC-V: Add EFI runtime services")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220528014132.91052-1-heinrich.schuchardt@xxxxxxxxxxxxx
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/riscv/kernel/efi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/efi.c b/arch/riscv/kernel/efi.c
index 024159298231..1aa540350abd 100644
--- a/arch/riscv/kernel/efi.c
+++ b/arch/riscv/kernel/efi.c
@@ -65,7 +65,7 @@ static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data)
if (md->attribute & EFI_MEMORY_RO) {
val = pte_val(pte) & ~_PAGE_WRITE;
- val = pte_val(pte) | _PAGE_READ;
+ val |= _PAGE_READ;
pte = __pte(val);
}
if (md->attribute & EFI_MEMORY_XP) {
--
2.35.1
