[kernel] r18956 - in dists/sid/linux-2.6/debian/patches: features/x86/efi-stub series

Ben Hutchings benh at alioth.debian.org
Fri Apr 27 03:36:26 UTC 2012


Author: benh
Date: Fri Apr 27 03:36:24 2012
New Revision: 18956

Log:
Apply upstream bug fixes for EFI stub support

Added:
   dists/sid/linux-2.6/debian/patches/features/x86/efi-stub/0012-x86-efi-Fix-endian-issues-and-unaligned-accesses.patch
   dists/sid/linux-2.6/debian/patches/features/x86/efi-stub/0013-x86-efi-Add-dedicated-EFI-stub-entry-point.patch
Modified:
   dists/sid/linux-2.6/debian/patches/series/base

Added: dists/sid/linux-2.6/debian/patches/features/x86/efi-stub/0012-x86-efi-Fix-endian-issues-and-unaligned-accesses.patch
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ dists/sid/linux-2.6/debian/patches/features/x86/efi-stub/0012-x86-efi-Fix-endian-issues-and-unaligned-accesses.patch	Fri Apr 27 03:36:24 2012	(r18956)
@@ -0,0 +1,125 @@
+From: Matt Fleming <matt.fleming at intel.com>
+Date: Tue, 28 Feb 2012 13:37:24 +0000
+Subject: [PATCH 12/13] x86, efi: Fix endian issues and unaligned accesses
+
+commit 92f42c50f227ad228f815a8f4eec872524dae3a5 upstream.
+
+We may need to convert the endianness of the data we read from/write
+to 'buf', so let's use {get,put}_unaligned_le32() to do that. Failure
+to do so can result in accessing invalid memory, leading to a
+segfault.  Stephen Rothwell noticed this bug while cross-building an
+x86_64 allmodconfig kernel on PowerPC.
+
+We need to read from and write to 'buf' a byte at a time otherwise
+it's possible we'll perform an unaligned access, which can lead to bus
+errors when cross-building an x86 kernel on risc architectures.
+
+Cc: H. Peter Anvin <hpa at zytor.com>
+Cc: Nick Bowler <nbowler at elliptictech.com>
+Tested-by: Stephen Rothwell <sfr at canb.auug.org.au>
+Reported-by: Stephen Rothwell <sfr at canb.auug.org.au>
+Signed-off-by: Matt Fleming <matt.fleming at intel.com>
+Link: http://lkml.kernel.org/r/1330436245-24875-6-git-send-email-matt@console-pimps.org
+Signed-off-by: H. Peter Anvin <hpa at zytor.com>
+---
+ arch/x86/boot/tools/build.c |   31 +++++++++++++++----------------
+ 1 file changed, 15 insertions(+), 16 deletions(-)
+
+diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
+index 4e9bd6b..f2ac95e 100644
+--- a/arch/x86/boot/tools/build.c
++++ b/arch/x86/boot/tools/build.c
+@@ -34,6 +34,7 @@
+ #include <fcntl.h>
+ #include <sys/mman.h>
+ #include <asm/boot.h>
++#include <tools/le_byteshift.h>
+ 
+ typedef unsigned char  u8;
+ typedef unsigned short u16;
+@@ -41,6 +42,7 @@ typedef unsigned long  u32;
+ 
+ #define DEFAULT_MAJOR_ROOT 0
+ #define DEFAULT_MINOR_ROOT 0
++#define DEFAULT_ROOT_DEV (DEFAULT_MAJOR_ROOT << 8 | DEFAULT_MINOR_ROOT)
+ 
+ /* Minimal number of setup sectors */
+ #define SETUP_SECT_MIN 5
+@@ -159,7 +161,7 @@ int main(int argc, char ** argv)
+ 		die("read-error on `setup'");
+ 	if (c < 1024)
+ 		die("The setup must be at least 1024 bytes");
+-	if (buf[510] != 0x55 || buf[511] != 0xaa)
++	if (get_unaligned_le16(&buf[510]) != 0xAA55)
+ 		die("Boot block hasn't got boot flag (0xAA55)");
+ 	fclose(file);
+ 
+@@ -171,8 +173,7 @@ int main(int argc, char ** argv)
+ 	memset(buf+c, 0, i-c);
+ 
+ 	/* Set the default root device */
+-	buf[508] = DEFAULT_MINOR_ROOT;
+-	buf[509] = DEFAULT_MAJOR_ROOT;
++	put_unaligned_le16(DEFAULT_ROOT_DEV, &buf[508]);
+ 
+ 	fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i);
+ 
+@@ -192,44 +193,42 @@ int main(int argc, char ** argv)
+ 
+ 	/* Patch the setup code with the appropriate size parameters */
+ 	buf[0x1f1] = setup_sectors-1;
+-	buf[0x1f4] = sys_size;
+-	buf[0x1f5] = sys_size >> 8;
+-	buf[0x1f6] = sys_size >> 16;
+-	buf[0x1f7] = sys_size >> 24;
++	put_unaligned_le32(sys_size, &buf[0x1f4]);
+ 
+ #ifdef CONFIG_EFI_STUB
+ 	file_sz = sz + i + ((sys_size * 16) - sz);
+ 
+-	pe_header = *(unsigned int *)&buf[0x3c];
++	pe_header = get_unaligned_le32(&buf[0x3c]);
+ 
+ 	/* Size of code */
+-	*(unsigned int *)&buf[pe_header + 0x1c] = file_sz;
++	put_unaligned_le32(file_sz, &buf[pe_header + 0x1c]);
+ 
+ 	/* Size of image */
+-	*(unsigned int *)&buf[pe_header + 0x50] = file_sz;
++	put_unaligned_le32(file_sz, &buf[pe_header + 0x50]);
+ 
+ #ifdef CONFIG_X86_32
+ 	/* Address of entry point */
+-	*(unsigned int *)&buf[pe_header + 0x28] = i;
++	put_unaligned_le32(i, &buf[pe_header + 0x28]);
+ 
+ 	/* .text size */
+-	*(unsigned int *)&buf[pe_header + 0xb0] = file_sz;
++	put_unaligned_le32(file_sz, &buf[pe_header + 0xb0]);
+ 
+ 	/* .text size of initialised data */
+-	*(unsigned int *)&buf[pe_header + 0xb8] = file_sz;
++	put_unaligned_le32(file_sz, &buf[pe_header + 0xb8]);
+ #else
+ 	/*
+ 	 * Address of entry point. startup_32 is at the beginning and
+ 	 * the 64-bit entry point (startup_64) is always 512 bytes
+ 	 * after.
+ 	 */
+-	*(unsigned int *)&buf[pe_header + 0x28] = i + 512;
++	put_unaligned_le32(i + 512, &buf[pe_header + 0x28]);
+ 
+ 	/* .text size */
+-	*(unsigned int *)&buf[pe_header + 0xc0] = file_sz;
++	put_unaligned_le32(file_sz, &buf[pe_header + 0xc0]);
+ 
+ 	/* .text size of initialised data */
+-	*(unsigned int *)&buf[pe_header + 0xc8] = file_sz;
++	put_unaligned_le32(file_sz, &buf[pe_header + 0xc8]);
++
+ #endif /* CONFIG_X86_32 */
+ #endif /* CONFIG_EFI_STUB */
+ 
+-- 
+1.7.10
+

Added: dists/sid/linux-2.6/debian/patches/features/x86/efi-stub/0013-x86-efi-Add-dedicated-EFI-stub-entry-point.patch
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ dists/sid/linux-2.6/debian/patches/features/x86/efi-stub/0013-x86-efi-Add-dedicated-EFI-stub-entry-point.patch	Fri Apr 27 03:36:24 2012	(r18956)
@@ -0,0 +1,143 @@
+From: Matt Fleming <matt.fleming at intel.com>
+Date: Sun, 15 Apr 2012 16:06:04 +0100
+Subject: [PATCH 13/13] x86, efi: Add dedicated EFI stub entry point
+
+commit b1994304fc399f5d3a5368c81111d713490c4799 upstream.
+
+The method used to work out whether we were booted by EFI firmware or
+via a boot loader is broken. Because efi_main() is always executed
+when booting from a boot loader we will dereference invalid pointers
+either on the stack (CONFIG_X86_32) or contained in %rdx
+(CONFIG_X86_64) when searching for an EFI System Table signature.
+
+Instead of dereferencing these invalid system table pointers, add a
+new entry point that is only used when booting from EFI firmware, when
+we know the pointer arguments will be valid. With this change legacy
+boot loaders will no longer execute efi_main(), but will instead skip
+EFI stub initialisation completely.
+
+[ hpa: Marking this for urgent/stable since it is a regression when
+  the option is enabled; without the option the patch has no effect ]
+
+Signed-off-by: Matt Fleming <matt.hfleming at intel.com>
+Link: http://lkml.kernel.org/r/1334584744.26997.14.camel@mfleming-mobl1.ger.corp.intel.com
+Reported-by: Jordan Justen <jordan.l.justen at intel.com>
+Signed-off-by: H. Peter Anvin <hpa at linux.intel.com>
+Cc: <stable at vger.kernel.org> v3.3
+---
+ arch/x86/boot/compressed/head_32.S |   14 +++++++++++---
+ arch/x86/boot/compressed/head_64.S |   22 ++++++++++++++++------
+ arch/x86/boot/tools/build.c        |   15 +++++++++++----
+ 3 files changed, 38 insertions(+), 13 deletions(-)
+
+diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
+index a055993..c85e3ac 100644
+--- a/arch/x86/boot/compressed/head_32.S
++++ b/arch/x86/boot/compressed/head_32.S
+@@ -33,6 +33,9 @@
+ 	__HEAD
+ ENTRY(startup_32)
+ #ifdef CONFIG_EFI_STUB
++	jmp	preferred_addr
++
++	.balign	0x10
+ 	/*
+ 	 * We don't need the return address, so set up the stack so
+ 	 * efi_main() can find its arugments.
+@@ -41,12 +44,17 @@ ENTRY(startup_32)
+ 
+ 	call	efi_main
+ 	cmpl	$0, %eax
+-	je	preferred_addr
+ 	movl	%eax, %esi
+-	call	1f
++	jne	2f
+ 1:
++	/* EFI init failed, so hang. */
++	hlt
++	jmp	1b
++2:
++	call	3f
++3:
+ 	popl	%eax
+-	subl	$1b, %eax
++	subl	$3b, %eax
+ 	subl	BP_pref_address(%esi), %eax
+ 	add	BP_code32_start(%esi), %eax
+ 	leal	preferred_addr(%eax), %eax
+diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
+index 558d76c..87e03a1 100644
+--- a/arch/x86/boot/compressed/head_64.S
++++ b/arch/x86/boot/compressed/head_64.S
+@@ -200,18 +200,28 @@ ENTRY(startup_64)
+ 	 * entire text+data+bss and hopefully all of memory.
+ 	 */
+ #ifdef CONFIG_EFI_STUB
+-	pushq	%rsi
++	/*
++	 * The entry point for the PE/COFF executable is 0x210, so only
++	 * legacy boot loaders will execute this jmp.
++	 */
++	jmp	preferred_addr
++
++	.org 0x210
+ 	mov	%rcx, %rdi
+ 	mov	%rdx, %rsi
+ 	call	efi_main
+-	popq	%rsi
+-	cmpq	$0,%rax
+-	je	preferred_addr
+ 	movq	%rax,%rsi
+-	call	1f
++	cmpq	$0,%rax
++	jne	2f
+ 1:
++	/* EFI init failed, so hang. */
++	hlt
++	jmp	1b
++2:
++	call	3f
++3:
+ 	popq	%rax
+-	subq	$1b, %rax
++	subq	$3b, %rax
+ 	subq	BP_pref_address(%rsi), %rax
+ 	add	BP_code32_start(%esi), %eax
+ 	leaq	preferred_addr(%rax), %rax
+diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
+index ed54976..24443a3 100644
+--- a/arch/x86/boot/tools/build.c
++++ b/arch/x86/boot/tools/build.c
+@@ -205,8 +205,13 @@ int main(int argc, char ** argv)
+ 	put_unaligned_le32(file_sz, &buf[pe_header + 0x50]);
+ 
+ #ifdef CONFIG_X86_32
+-	/* Address of entry point */
+-	put_unaligned_le32(i, &buf[pe_header + 0x28]);
++	/*
++	 * Address of entry point.
++	 *
++	 * The EFI stub entry point is +16 bytes from the start of
++	 * the .text section.
++	 */
++	put_unaligned_le32(i + 16, &buf[pe_header + 0x28]);
+ 
+ 	/* .text size */
+ 	put_unaligned_le32(file_sz, &buf[pe_header + 0xb0]);
+@@ -217,9 +222,11 @@ int main(int argc, char ** argv)
+ 	/*
+ 	 * Address of entry point. startup_32 is at the beginning and
+ 	 * the 64-bit entry point (startup_64) is always 512 bytes
+-	 * after.
++	 * after. The EFI stub entry point is 16 bytes after that, as
++	 * the first instruction allows legacy loaders to jump over
++	 * the EFI stub initialisation
+ 	 */
+-	put_unaligned_le32(i + 512, &buf[pe_header + 0x28]);
++	put_unaligned_le32(i + 528, &buf[pe_header + 0x28]);
+ 
+ 	/* .text size */
+ 	put_unaligned_le32(file_sz, &buf[pe_header + 0xc0]);
+-- 
+1.7.10
+

Modified: dists/sid/linux-2.6/debian/patches/series/base
==============================================================================
--- dists/sid/linux-2.6/debian/patches/series/base	Fri Apr 27 02:44:50 2012	(r18955)
+++ dists/sid/linux-2.6/debian/patches/series/base	Fri Apr 27 03:36:24 2012	(r18956)
@@ -183,6 +183,9 @@
 + features/x86/efi-stub/0009-x86-efi-EFI-boot-stub-support.patch
 + features/x86/efi-stub/0010-x86-efi-Break-up-large-initrd-reads.patch
 + features/x86/efi-stub/0011-x86-efi-Fix-pointer-math-issue-in-handle_ramdisks.patch
++ features/x86/efi-stub/0012-x86-efi-Fix-endian-issues-and-unaligned-accesses.patch
++ features/x86/efi-stub/0013-x86-efi-Add-dedicated-EFI-stub-entry-point.patch
+
 + bugfix/all/brcmsmac-INTERMEDIATE-but-not-AMPDU-only-when-tracin.patch
 + bugfix/all/NFSv4-Rate-limit-the-state-manager-for-lock-reclaim-.patch
 + bugfix/all/NFSv4-Ensure-that-the-LOCK-code-sets-exception-inode.patch



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