Enable Intel CET in i686

Resolves: #1910368

xz-5.2.5-enable_CET.patch

@@ -0,0 +1,70 @@
+From: H.J. Lu <hjl.tools@gmail.com>
+Date: Wed, 23 Dec 2020 15:49:04 +0100 (06:49 -0800)
+Subject: [PATCH] liblzma: Enable Intel CET in x86 CRC assembly codes
+
+When Intel CET is enabled, we need to include <cet.h> in assembly codes
+to mark Intel CET support and add _CET_ENDBR to indirect jump targets.
+
+Tested on Intel Tiger Lake under CET enabled Linux.
+---
+ src/liblzma/check/crc32_x86.S | 9 +++++++++
+ src/liblzma/check/crc64_x86.S | 9 +++++++++
+ 2 files changed, 18 insertions(+)
+
+diff --git a/src/liblzma/check/crc32_x86.S b/src/liblzma/check/crc32_x86.S
+index 67f68a4..e3745e6 100644
+--- a/src/liblzma/check/crc32_x86.S
++++ b/src/liblzma/check/crc32_x86.S
+@@ -51,6 +51,14 @@ init_table(void)
+  * extern uint32_t lzma_crc32(const uint8_t *buf, size_t size, uint32_t crc);
+  */
+ 
++/* When Intel CET is enabled, include <cet.h> in assembly code to mark
++   Intel CET support.  */
++#ifdef __CET__
++# include <cet.h>
++#else
++# define _CET_ENDBR
++#endif
++
+ /*
+  * On some systems, the functions need to be prefixed. The prefix is
+  * usually an underscore.
+@@ -83,6 +91,7 @@ init_table(void)
+ 
+ 	ALIGN(4, 16)
+ LZMA_CRC32:
++	_CET_ENDBR
+ 	/*
+ 	 * Register usage:
+ 	 * %eax crc
+diff --git a/src/liblzma/check/crc64_x86.S b/src/liblzma/check/crc64_x86.S
+index f5bb84b..7ee08f6 100644
+--- a/src/liblzma/check/crc64_x86.S
++++ b/src/liblzma/check/crc64_x86.S
+@@ -41,6 +41,14 @@ init_table(void)
+  * extern uint64_t lzma_crc64(const uint8_t *buf, size_t size, uint64_t crc);
+  */
+ 
++/* When Intel CET is enabled, include <cet.h> in assembly code to mark
++   Intel CET support.  */
++#ifdef __CET__
++# include <cet.h>
++#else
++# define _CET_ENDBR
++#endif
++
+ /*
+  * On some systems, the functions need to be prefixed. The prefix is
+  * usually an underscore.
+@@ -73,6 +81,7 @@ init_table(void)
+ 
+ 	ALIGN(4, 16)
+ LZMA_CRC64:
++	_CET_ENDBR
+ 	/*
+ 	 * Register usage:
+ 	 * %eax crc LSB
+-- 
+2.26.0
+

xz.spec

@@ -4,7 +4,7 @@
 Summary:	LZMA compression utilities
 Name:		xz
 Version:	5.2.5
-Release:	3%{?dist}
+Release:	4%{?dist}
 
 # Scripts xz{grep,diff,less,more} and symlinks (copied from gzip) are
 # GPLv2+, binaries are Public Domain (linked against LGPL getopt_long but its
@@ -16,6 +16,8 @@ Source0:	http://tukaani.org/%{name}/%{name}-%{version}.tar.xz
 Source100:	colorxzgrep.sh
 Source101:	colorxzgrep.csh
 
+Patch1:   xz-5.2.5-enable_CET.patch
+
 URL:		http://tukaani.org/%{name}/
 Requires:	%{name}-libs%{?_isa} = %{version}-%{release}
 
@@ -80,7 +82,7 @@ commands that deal with the older LZMA format.
 
 
 %prep
-%autosetup
+%autosetup -p1
 
 
 %build
@@ -157,6 +159,9 @@ LD_LIBRARY_PATH=$PWD/src/liblzma/.libs make check
 
 
 %changelog
+* Mon Mar 30 2020 Ondrej Dubaj <odubaj@redhat.com> - 5.2.5-4
+- Enabled CET for i686 (#1910368)
+
 * Wed Jul 29 2020 Fedora Release Engineering <releng@fedoraproject.org> - 5.2.5-3
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_33_Mass_Rebuild