arm64/efistub: Clean up KASLR logic

JIRA: https://issues.redhat.com/browse/RHEL-33066

commit 12a01f6
Author: Ard Biesheuvel <ardb@kernel.org>
Date:   Wed Jul 10 12:22:46 2024 +0200

    arm64/efistub: Clean up KASLR logic

    Clean up some redundant code in the KASLR placement handling logic. No
    functional change intended.

    Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>

Author: LennySzubowicz

drivers/firmware/efi/libstub/arm64-stub.c

@@ -21,7 +21,6 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 				 efi_loaded_image_t *image,
 				 efi_handle_t image_handle)
 {
-	efi_status_t status;
 	unsigned long kernel_size, kernel_codesize, kernel_memsize;
 
 	if (image->image_base != _text) {
@@ -39,15 +38,9 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 	*reserve_size = kernel_memsize;
 	*image_addr = (unsigned long)_text;
 
-	status = efi_kaslr_relocate_kernel(image_addr,
-					   reserve_addr, reserve_size,
-					   kernel_size, kernel_codesize,
-					   kernel_memsize,
-					   efi_kaslr_get_phys_seed(image_handle));
-	if (status != EFI_SUCCESS)
-		return status;
-
-	return EFI_SUCCESS;
+	return efi_kaslr_relocate_kernel(image_addr, reserve_addr, reserve_size,
+					 kernel_size, kernel_codesize, kernel_memsize,
+					 efi_kaslr_get_phys_seed(image_handle));
 }
 
 asmlinkage void primary_entry(void);

drivers/firmware/efi/libstub/kaslr.c

@@ -18,8 +18,6 @@
  */
 u32 efi_kaslr_get_phys_seed(efi_handle_t image_handle)
 {
-	efi_status_t status;
-	u32 phys_seed;
 	efi_guid_t li_fixed_proto = LINUX_EFI_LOADED_IMAGE_FIXED_GUID;
 	void *p;
 
@@ -32,18 +30,20 @@ u32 efi_kaslr_get_phys_seed(efi_handle_t image_handle)
 			       &li_fixed_proto, &p) == EFI_SUCCESS) {
 		efi_info("Image placement fixed by loader\n");
 	} else {
+		efi_status_t status;
+		u32 phys_seed;
+
 		status = efi_get_random_bytes(sizeof(phys_seed),
 					      (u8 *)&phys_seed);
-		if (status == EFI_SUCCESS) {
+		if (status == EFI_SUCCESS)
 			return phys_seed;
-		} else if (status == EFI_NOT_FOUND) {
+
+		if (status == EFI_NOT_FOUND)
 			efi_info("EFI_RNG_PROTOCOL unavailable\n");
-			efi_nokaslr = true;
-		} else if (status != EFI_SUCCESS) {
-			efi_err("efi_get_random_bytes() failed (0x%lx)\n",
-				status);
-			efi_nokaslr = true;
-		}
+		else
+			efi_err("efi_get_random_bytes() failed (0x%lx)\n", status);
+
+		efi_nokaslr = true;
 	}
 
 	return 0;