From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AED1C3F2C6 for ; Sun, 8 Mar 2020 08:10:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9BD12084E for ; Sun, 8 Mar 2020 08:10:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583655005; bh=Y3FNhUUljVYLAsepqBIFw9PWxLAxG9XYE6JMQ70hfbE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=TnDpJ7ntR6tp/MspbIfsqw0X0doGVi35JuAOBSUeS5tB7e75ZV5hWhbn1UOj1tAa4 rsd8yuQDmUSShvMV4woOyxyTmKMDVKqPK5fb+vb8vbGn8hWlc0ZyAKjWRRnSEhuSos ihuBdaF5ORboye4n0XrK1yHnky64F15vbB4bxCrI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726696AbgCHIKF (ORCPT ); Sun, 8 Mar 2020 04:10:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:37672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726271AbgCHIKE (ORCPT ); Sun, 8 Mar 2020 04:10:04 -0400 Received: from e123331-lin.home (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3622A2166E; Sun, 8 Mar 2020 08:10:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583655003; bh=Y3FNhUUljVYLAsepqBIFw9PWxLAxG9XYE6JMQ70hfbE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=soY/RX4AC3duuz16mKip/TDD/y4xcxJZSZNjV8KVNcGuOqxOkSNvmK2GVOWBCXQ8J Wa/VUK7enb8UJGx3UzN4oZS+WQcWfGWrwfW3BqNgZI9Xd/TEc+tGdWboy63XDmschM vd1I9ya3ncd0vyY55l9/f/ElWHXp1Bl+OmHs72Yg= From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-kernel@vger.kernel.org, Arvind Sankar , Christoph Hellwig , David Hildenbrand , Davidlohr Bueso , Guenter Roeck , Heinrich Schuchardt , Jonathan Corbet , Lukas Bulwahn , Masahiro Yamada , Nikolai Merinov , Tom Lendacky , Vladis Dronov Subject: [PATCH 16/28] efi/x86: Decompress at start of PE image load address Date: Sun, 8 Mar 2020 09:08:47 +0100 Message-Id: <20200308080859.21568-17-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200308080859.21568-1-ardb@kernel.org> References: <20200308080859.21568-1-ardb@kernel.org> Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Arvind Sankar When booted via PE loader, define image_offset to hold the offset of startup_32 from the start of the PE image, and use it as the start of the decompression buffer. Signed-off-by: Arvind Sankar Link: https://lore.kernel.org/r/20200303221205.4048668-3-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel --- arch/x86/boot/compressed/head_32.S | 17 ++++++++++ arch/x86/boot/compressed/head_64.S | 42 +++++++++++++++++++++++-- drivers/firmware/efi/libstub/x86-stub.c | 17 ++++++++-- 3 files changed, 70 insertions(+), 6 deletions(-) diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S index 2a8965aec234..f7b52ccaa4ee 100644 --- a/arch/x86/boot/compressed/head_32.S +++ b/arch/x86/boot/compressed/head_32.S @@ -100,6 +100,19 @@ SYM_FUNC_START(startup_32) #ifdef CONFIG_RELOCATABLE movl %edx, %ebx + +#ifdef CONFIG_EFI_STUB +/* + * If we were loaded via the EFI LoadImage service, startup_32 will be at an + * offset to the start of the space allocated for the image. efi_pe_entry will + * setup image_offset to tell us where the image actually starts, so that we + * can use the full available buffer. + * image_offset = startup_32 - image_base + * Otherwise image_offset will be zero and have no effect on the calculations. + */ + subl image_offset(%edx), %ebx +#endif + movl BP_kernel_alignment(%esi), %eax decl %eax addl %eax, %ebx @@ -227,6 +240,10 @@ SYM_DATA_START_LOCAL(gdt) .quad 0x00cf92000000ffff /* __KERNEL_DS */ SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) +#ifdef CONFIG_EFI_STUB +SYM_DATA(image_offset, .long 0) +#endif + /* * Stack and heap for uncompression */ diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 1199c4ef0c83..4d4b4763a770 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -99,6 +99,19 @@ SYM_FUNC_START(startup_32) #ifdef CONFIG_RELOCATABLE movl %ebp, %ebx + +#ifdef CONFIG_EFI_STUB +/* + * If we were loaded via the EFI LoadImage service, startup_32 will be at an + * offset to the start of the space allocated for the image. efi_pe_entry will + * setup image_offset to tell us where the image actually starts, so that we + * can use the full available buffer. + * image_offset = startup_32 - image_base + * Otherwise image_offset will be zero and have no effect on the calculations. + */ + subl image_offset(%ebp), %ebx +#endif + movl BP_kernel_alignment(%esi), %eax decl %eax addl %eax, %ebx @@ -111,9 +124,8 @@ SYM_FUNC_START(startup_32) 1: /* Target address to relocate to for decompression */ - movl BP_init_size(%esi), %eax - subl $_end, %eax - addl %eax, %ebx + addl BP_init_size(%esi), %ebx + subl $_end, %ebx /* * Prepare for entering 64 bit mode @@ -299,6 +311,20 @@ SYM_CODE_START(startup_64) /* Start with the delta to where the kernel will run at. */ #ifdef CONFIG_RELOCATABLE leaq startup_32(%rip) /* - $startup_32 */, %rbp + +#ifdef CONFIG_EFI_STUB +/* + * If we were loaded via the EFI LoadImage service, startup_32 will be at an + * offset to the start of the space allocated for the image. efi_pe_entry will + * setup image_offset to tell us where the image actually starts, so that we + * can use the full available buffer. + * image_offset = startup_32 - image_base + * Otherwise image_offset will be zero and have no effect on the calculations. + */ + movl image_offset(%rip), %eax + subq %rax, %rbp +#endif + movl BP_kernel_alignment(%rsi), %eax decl %eax addq %rax, %rbp @@ -647,6 +673,10 @@ SYM_DATA_START_LOCAL(gdt) .quad 0x0000000000000000 /* TS continued */ SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) +#ifdef CONFIG_EFI_STUB +SYM_DATA(image_offset, .long 0) +#endif + #ifdef CONFIG_EFI_MIXED SYM_DATA_LOCAL(efi32_boot_args, .long 0, 0, 0) SYM_DATA(efi_is64, .byte 1) @@ -712,6 +742,12 @@ SYM_FUNC_START(efi32_pe_entry) movl -4(%ebp), %esi // loaded_image movl LI32_image_base(%esi), %esi // loaded_image->image_base movl %ebx, %ebp // startup_32 for efi32_pe_stub_entry + /* + * We need to set the image_offset variable here since startup_32 will + * use it before we get to the 64-bit efi_pe_entry in C code. + */ + subl %esi, %ebx + movl %ebx, image_offset(%ebp) // save image_offset jmp efi32_pe_stub_entry 2: popl %edi // restore callee-save registers diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c index 69a942f0640b..96bc4a8733c8 100644 --- a/drivers/firmware/efi/libstub/x86-stub.c +++ b/drivers/firmware/efi/libstub/x86-stub.c @@ -19,6 +19,7 @@ static efi_system_table_t *sys_table; extern const bool efi_is64; +extern u32 image_offset; __pure efi_system_table_t *efi_system_table(void) { @@ -365,6 +366,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, struct boot_params *boot_params; struct setup_header *hdr; efi_loaded_image_t *image; + void *image_base; efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID; int options_size = 0; efi_status_t status; @@ -385,7 +387,10 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, efi_exit(handle, status); } - hdr = &((struct boot_params *)efi_table_attr(image, image_base))->hdr; + image_base = efi_table_attr(image, image_base); + image_offset = (void *)startup_32 - image_base; + + hdr = &((struct boot_params *)image_base)->hdr; above4g = hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G; status = efi_allocate_pages(0x4000, (unsigned long *)&boot_params, @@ -400,7 +405,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, hdr = &boot_params->hdr; /* Copy the second sector to boot_params */ - memcpy(&hdr->jump, efi_table_attr(image, image_base) + 512, 512); + memcpy(&hdr->jump, image_base + 512, 512); /* * Fill out some of the header fields ourselves because the @@ -727,7 +732,7 @@ unsigned long efi_main(efi_handle_t handle, * If the kernel isn't already loaded at the preferred load * address, relocate it. */ - if (bzimage_addr != hdr->pref_address) { + if (bzimage_addr - image_offset != hdr->pref_address) { status = efi_relocate_kernel(&bzimage_addr, hdr->init_size, hdr->init_size, hdr->pref_address, @@ -737,6 +742,12 @@ unsigned long efi_main(efi_handle_t handle, efi_printk("efi_relocate_kernel() failed!\n"); goto fail; } + /* + * Now that we've copied the kernel elsewhere, we no longer + * have a setup block before startup_32, so reset image_offset + * to zero in case it was set earlier. + */ + image_offset = 0; } /* -- 2.17.1