Hi Heinrich,
On 29/09/2024 16:02, Heinrich Schuchardt wrote:
The IMAGE_DLLCHARACTERISTICS_NX_COMPAT informs the firmware that the EFI binary does not rely on pages that are both executable and writable.
The flag is used by some distro versions of GRUB to decide if the EFI binary may be executed.
As the Linux kernel neither has RWX sections nor needs RWX pages for relocation we should set the flag.
Cc: Ard Biesheuvel ardb@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com
arch/riscv/kernel/efi-header.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S index 515b2dfbca75..c5f17c2710b5 100644 --- a/arch/riscv/kernel/efi-header.S +++ b/arch/riscv/kernel/efi-header.S @@ -64,7 +64,7 @@ extra_header_fields: .long efi_header_end - _start // SizeOfHeaders .long 0 // CheckSum .short IMAGE_SUBSYSTEM_EFI_APPLICATION // Subsystem
- .short 0 // DllCharacteristics
- .short IMAGE_DLL_CHARACTERISTICS_NX_COMPAT // DllCharacteristics .quad 0 // SizeOfStackReserve .quad 0 // SizeOfStackCommit .quad 0 // SizeOfHeapReserve
I don't understand if this fixes something or not: what could go wrong if we don't do this?
Thanks,
Alex