Merge tag 'efi-fixes-for-v6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:

 - Wipe screen_info after allocating it from the heap - used by arm32
   and EFI zboot, other EFI architectures allocate it statically

 - Revert to allocating boot_params from the heap on x86 when entering
   via the native PE entrypoint, to work around a regression on older
   Dell hardware

* tag 'efi-fixes-for-v6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  x86/efistub: Revert to heap allocated boot_params for PE entrypoint
  efi/libstub: Zero initialize heap allocated struct screen_info

2 files changed, 17 insertions, 5 deletions

diff --git a/drivers/firmware/efi/libstub/screen_info.c b/drivers/firmware/efi/libstub/screen_info.c
index a51ec201ca3c..5d3a1e32d177 100644
--- a/drivers/firmware/efi/libstub/screen_info.c
+++ b/drivers/firmware/efi/libstub/screen_info.c
@@ -32,6 +32,8 @@ struct screen_info *__alloc_screen_info(void)
 	if (status != EFI_SUCCESS)
 		return NULL;
 
+	memset(si, 0, sizeof(*si));
+
 	status = efi_bs_call(install_configuration_table,
 			     &screen_info_guid, si);
 	if (status == EFI_SUCCESS)
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 078055b054e3..f8e465da344d 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -534,11 +534,12 @@ void __noreturn efi_stub_entry(efi_handle_t handle,
 efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 				   efi_system_table_t *sys_table_arg)
 {
-	static struct boot_params boot_params __page_aligned_bss;
-	struct setup_header *hdr = &boot_params.hdr;
 	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
+	struct boot_params *boot_params;
+	struct setup_header *hdr;
 	int options_size = 0;
 	efi_status_t status;
+	unsigned long alloc;
 	char *cmdline_ptr;
 
 	efi_system_table = sys_table_arg;
@@ -553,6 +554,13 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 		efi_exit(handle, status);
 	}
 
+	status = efi_allocate_pages(PARAM_SIZE, &alloc, ULONG_MAX);
+	if (status != EFI_SUCCESS)
+		efi_exit(handle, status);
+
+	boot_params = memset((void *)alloc, 0x0, PARAM_SIZE);
+	hdr	    = &boot_params->hdr;
+
 	/* Assign the setup_header fields that the kernel actually cares about */
 	hdr->root_flags	= 1;
 	hdr->vid_mode	= 0xffff;
@@ -562,13 +570,15 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 
 	/* Convert unicode cmdline to ascii */
 	cmdline_ptr = efi_convert_cmdline(image, &options_size);
-	if (!cmdline_ptr)
+	if (!cmdline_ptr) {
+		efi_free(PARAM_SIZE, alloc);
 		efi_exit(handle, EFI_OUT_OF_RESOURCES);
+	}
 
 	efi_set_u64_split((unsigned long)cmdline_ptr, &hdr->cmd_line_ptr,
-			  &boot_params.ext_cmd_line_ptr);
+			  &boot_params->ext_cmd_line_ptr);
 
-	efi_stub_entry(handle, sys_table_arg, &boot_params);
+	efi_stub_entry(handle, sys_table_arg, boot_params);
 	/* not reached */
 }