PATCHES/patches/0048-x86-boot-Fix-EFI-stub-alignment.patch

From cae330868328570a6d2ea5afe38eda0cddb444cb Mon Sep 17 00:00:00 2001
From: Ben Hutchings <ben@decadent.org.uk>
Date: Sun, 16 Sep 2018 16:22:47 +0100
Subject: [PATCH 048/145] x86: boot: Fix EFI stub alignment

[ Upstream commit 9c1442a9d039a1a3302fa93e9a11001c5f23b624 ]

We currently align the end of the compressed image to a multiple of
16.  However, the PE-COFF header included in the EFI stub says that
the file alignment is 32 bytes, and when adding an EFI signature to
the file it must first be padded to this alignment.

sbsigntool commands warn about this:

  warning: file-aligned section .text extends beyond end of file
  warning: checksum areas are greater than image size. Invalid section table?

Worse, pesign -at least when creating a detached signature- uses the
hash of the unpadded file, resulting in an invalid signature if
padding is required.

Avoid both these problems by increasing alignment to 32 bytes when
CONFIG_EFI_STUB is enabled.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/x86/boot/tools/build.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
index d4e6cd4577e5..bf0e82400358 100644
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -391,6 +391,13 @@ int main(int argc, char ** argv)
                die("Unable to mmap '%s': %m", argv[2]);
        /* Number of 16-byte paragraphs, including space for a 4-byte CRC */
        sys_size = (sz + 15 + 4) / 16;
+#ifdef CONFIG_EFI_STUB
+       /*
+        * COFF requires minimum 32-byte alignment of sections, and
+        * adding a signature is problematic without that alignment.
+        */
+       sys_size = (sys_size + 1) & ~1;
+#endif
 
        /* Patch the setup code with the appropriate size parameters */
        buf[0x1f1] = setup_sectors-1;
-- 
2.19.1

1	From cae330868328570a6d2ea5afe38eda0cddb444cb Mon Sep 17 00:00:00 2001
2	From: Ben Hutchings <ben@decadent.org.uk>
3	Date: Sun, 16 Sep 2018 16:22:47 +0100
4	Subject: [PATCH 048/145] x86: boot: Fix EFI stub alignment
5
6	[ Upstream commit 9c1442a9d039a1a3302fa93e9a11001c5f23b624 ]
7
8	We currently align the end of the compressed image to a multiple of
9	16. However, the PE-COFF header included in the EFI stub says that
10	the file alignment is 32 bytes, and when adding an EFI signature to
11	the file it must first be padded to this alignment.
12
13	sbsigntool commands warn about this:
14
15	warning: file-aligned section .text extends beyond end of file
16	warning: checksum areas are greater than image size. Invalid section table?
17
18	Worse, pesign -at least when creating a detached signature- uses the
19	hash of the unpadded file, resulting in an invalid signature if
20	padding is required.
21
22	Avoid both these problems by increasing alignment to 32 bytes when
23	CONFIG_EFI_STUB is enabled.
24
25	Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
26	Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
27	Signed-off-by: Sasha Levin <sashal@kernel.org>
28	---
29	arch/x86/boot/tools/build.c \| 7 +++++++
30	1 file changed, 7 insertions(+)
31
32	diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
33	index d4e6cd4577e5..bf0e82400358 100644
34	--- a/arch/x86/boot/tools/build.c
35	+++ b/arch/x86/boot/tools/build.c
36	@@ -391,6 +391,13 @@ int main(int argc, char ** argv)
37	die("Unable to mmap '%s': %m", argv[2]);
38	/* Number of 16-byte paragraphs, including space for a 4-byte CRC */
39	sys_size = (sz + 15 + 4) / 16;
40	+#ifdef CONFIG_EFI_STUB
41	+ /*
42	+ * COFF requires minimum 32-byte alignment of sections, and
43	+ * adding a signature is problematic without that alignment.
44	+ */
45	+ sys_size = (sys_size + 1) & ~1;
46	+#endif
47
48	/* Patch the setup code with the appropriate size parameters */
49	buf[0x1f1] = setup_sectors-1;
50	--
51	2.19.1
52