Merge tag 'efi-fixes-for-v6.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:
 "These address all the outstanding EFI/x86 boot related regressions:

   - Revert to the old initrd memory allocation soft limit of INT_MAX,
     which was dropped inadvertently

   - Ensure that startup_32() is entered with a valid boot_params
     pointer when using the new EFI mixed mode protocol

   - Fix a compiler warning introduced by a fix from the previous pull"

* tag 'efi-fixes-for-v6.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  x86/efistub: Reinstate soft limit for initrd loading
  efi/libstub: Cast away type warning in use of max()
  x86/efistub: Add missing boot_params for mixed mode compat entry

3 files changed, 17 insertions, 6 deletions

diff --git a/arch/x86/boot/compressed/efi_mixed.S b/arch/x86/boot/compressed/efi_mixed.S
index 719e939050cbfa..876fc6d46a1318 100644
--- a/arch/x86/boot/compressed/efi_mixed.S
+++ b/arch/x86/boot/compressed/efi_mixed.S
@@ -15,10 +15,12 @@
  */
 
 #include <linux/linkage.h>
+#include <asm/asm-offsets.h>
 #include <asm/msr.h>
 #include <asm/page_types.h>
 #include <asm/processor-flags.h>
 #include <asm/segment.h>
+#include <asm/setup.h>
 
 	.code64
 	.text
@@ -149,6 +151,7 @@ SYM_FUNC_END(__efi64_thunk)
 SYM_FUNC_START(efi32_stub_entry)
 	call	1f
 1:	popl	%ecx
+	leal	(efi32_boot_args - 1b)(%ecx), %ebx
 
 	/* Clear BSS */
 	xorl	%eax, %eax
@@ -163,6 +166,7 @@ SYM_FUNC_START(efi32_stub_entry)
 	popl	%ecx
 	popl	%edx
 	popl	%esi
+	movl	%esi, 8(%ebx)
 	jmp	efi32_entry
 SYM_FUNC_END(efi32_stub_entry)
 #endif
@@ -239,8 +243,6 @@ SYM_FUNC_END(efi_enter32)
  *
  * Arguments:	%ecx	image handle
  * 		%edx	EFI system table pointer
- *		%esi	struct bootparams pointer (or NULL when not using
- *			the EFI handover protocol)
  *
  * Since this is the point of no return for ordinary execution, no registers
  * are considered live except for the function parameters. [Note that the EFI
@@ -266,9 +268,18 @@ SYM_FUNC_START_LOCAL(efi32_entry)
 	leal	(efi32_boot_args - 1b)(%ebx), %ebx
 	movl	%ecx, 0(%ebx)
 	movl	%edx, 4(%ebx)
-	movl	%esi, 8(%ebx)
 	movb	$0x0, 12(%ebx)          // efi_is64
 
+	/*
+	 * Allocate some memory for a temporary struct boot_params, which only
+	 * needs the minimal pieces that startup_32() relies on.
+	 */
+	subl	$PARAM_SIZE, %esp
+	movl	%esp, %esi
+	movl	$PAGE_SIZE, BP_kernel_alignment(%esi)
+	movl	$_end - 1b, BP_init_size(%esi)
+	subl	$startup_32 - 1b, BP_init_size(%esi)
+
 	/* Disable paging */
 	movl	%cr0, %eax
 	btrl	$X86_CR0_PG_BIT, %eax
@@ -294,8 +305,7 @@ SYM_FUNC_START(efi32_pe_entry)
 
 	movl	8(%ebp), %ecx			// image_handle
 	movl	12(%ebp), %edx			// sys_table
-	xorl	%esi, %esi
-	jmp	efi32_entry			// pass %ecx, %edx, %esi
+	jmp	efi32_entry			// pass %ecx, %edx
 						// no other registers remain live
 
 2:	popl	%edi				// restore callee-save registers
diff --git a/drivers/firmware/efi/libstub/randomalloc.c b/drivers/firmware/efi/libstub/randomalloc.c
index 7e185285955021..c41e7b2091cdd1 100644
--- a/drivers/firmware/efi/libstub/randomalloc.c
+++ b/drivers/firmware/efi/libstub/randomalloc.c
@@ -120,7 +120,7 @@ efi_status_t efi_random_alloc(unsigned long size,
 			continue;
 		}
 
-		target = round_up(max(md->phys_addr, alloc_min), align) + target_slot * align;
+		target = round_up(max_t(u64, md->phys_addr, alloc_min), align) + target_slot * align;
 		pages = size / EFI_PAGE_SIZE;
 
 		status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 6a6ffc6707bd0e..d5a8182cf2e1cc 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -496,6 +496,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	hdr->vid_mode	= 0xffff;
 
 	hdr->type_of_loader = 0x21;
+	hdr->initrd_addr_max = INT_MAX;
 
 	/* Convert unicode cmdline to ascii */
 	cmdline_ptr = efi_convert_cmdline(image, &options_size);