From: Peter Jones <[email protected]>
On platforms where the firmware uses DXE, but which do not implement the
EFI Memory Attribute Protocol, we implement W^X support using DXE's
set_memory_attributes() call. This call will fail without making any
changes if an attribute is set that isn't supported on the platform.
This patch changes efi_adjust_memory_range_protection() to avoid trying
to set any attribute bits that aren't set in the memory region's
capability flags.
Signed-off-by: Peter Jones <[email protected]>
---
drivers/firmware/efi/libstub/mem.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
index 50a0b649b75a..b86ea2920d5e 100644
--- a/drivers/firmware/efi/libstub/mem.c
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -195,6 +195,7 @@ static efi_status_t adjust_mem_attrib_dxe(efi_physical_addr_t rounded_start,
desc.attributes &= ~(EFI_MEMORY_RO | EFI_MEMORY_XP);
desc.attributes |= attributes;
+ desc.attributes &= desc.capabilities;
unprotect_start = max(rounded_start, desc.base_address);
unprotect_size = min(rounded_end, next) - unprotect_start;
--
2.37.4