diff options
6 files changed, 542 insertions, 7 deletions
diff --git a/libre/linux-libre-pae/0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch b/libre/linux-libre-pae/0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch index c2fe2b80a..9d8cde749 100644 --- a/libre/linux-libre-pae/0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch +++ b/libre/linux-libre-pae/0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch @@ -1,7 +1,7 @@ -From b38ba076b5049a77bf79f2c8cd224a77dea89bf3 Mon Sep 17 00:00:00 2001 +From 2efb3d95a5e8a14c097d570a61751f36d0be5215 Mon Sep 17 00:00:00 2001 From: "Jan Alexander Steffens (heftig)" <jan.steffens@gmail.com> Date: Mon, 16 Sep 2019 04:53:20 +0200 -Subject: [PATCH] ZEN: Add sysctl and CONFIG to disallow unprivileged +Subject: [PATCH 1/5] ZEN: Add sysctl and CONFIG to disallow unprivileged CLONE_NEWUSER Our default behavior continues to match the vanilla kernel. diff --git a/libre/linux-libre-pae/0002-gcc-plugins-drop-support-for-GCC-4.7.patch b/libre/linux-libre-pae/0002-gcc-plugins-drop-support-for-GCC-4.7.patch new file mode 100644 index 000000000..bec32c9b9 --- /dev/null +++ b/libre/linux-libre-pae/0002-gcc-plugins-drop-support-for-GCC-4.7.patch @@ -0,0 +1,277 @@ +From 5dd873b339bffa037dafd0188375fc13564bbe93 Mon Sep 17 00:00:00 2001 +From: Masahiro Yamada <masahiroy@kernel.org> +Date: Sun, 29 Mar 2020 20:08:32 +0900 +Subject: [PATCH 2/5] gcc-plugins: drop support for GCC <= 4.7 + +Nobody was opposed to raising minimum GCC version to 4.8 [1] +So, we will drop GCC <= 4.7 support sooner or later. + +We always use C++ compiler for building plugins for GCC >= 4.8. + +This commit drops the plugin support for GCC <= 4.7 a bit earlier, +which allows us to dump lots of code. + +[1] https://lkml.org/lkml/2020/1/23/545 + +Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> +Acked-by: Kees Cook <keescook@chromium.org> +--- + scripts/Kconfig.include | 3 -- + scripts/Makefile.build | 2 +- + scripts/Makefile.clean | 1 - + scripts/Makefile.host | 23 +-------------- + scripts/gcc-plugin.sh | 55 +++--------------------------------- + scripts/gcc-plugins/Kconfig | 12 ++------ + scripts/gcc-plugins/Makefile | 21 ++++---------- + 7 files changed, 14 insertions(+), 103 deletions(-) + +diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include +index 496d11c92c97..033f6efd92d3 100644 +--- a/scripts/Kconfig.include ++++ b/scripts/Kconfig.include +@@ -42,9 +42,6 @@ $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found) + # Fail if the linker is gold as it's not capable of linking the kernel proper + $(error-if,$(success, $(LD) -v | grep -q gold), gold linker '$(LD)' not supported) + +-# gcc version including patch level +-gcc-version := $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) +- + # machine bit flags + # $(m32-flag): -m32 if the compiler supports it, or an empty string otherwise. + # $(m64-flag): -m64 if the compiler supports it, or an empty string otherwise. +diff --git a/scripts/Makefile.build b/scripts/Makefile.build +index a1730d42e5f3..eec789d7a63a 100644 +--- a/scripts/Makefile.build ++++ b/scripts/Makefile.build +@@ -46,7 +46,7 @@ include $(kbuild-file) + include scripts/Makefile.lib + + # Do not include host rules unless needed +-ifneq ($(hostprogs)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),) ++ifneq ($(hostprogs)$(hostcxxlibs-y)$(hostcxxlibs-m),) + include scripts/Makefile.host + endif + +diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean +index 1e4206566a82..075f0cc2d8d7 100644 +--- a/scripts/Makefile.clean ++++ b/scripts/Makefile.clean +@@ -30,7 +30,6 @@ subdir-ymn := $(addprefix $(obj)/,$(subdir-ymn)) + __clean-files := $(extra-y) $(extra-m) $(extra-) \ + $(always) $(always-y) $(always-m) $(always-) $(targets) $(clean-files) \ + $(hostprogs) $(hostprogs-y) $(hostprogs-m) $(hostprogs-) \ +- $(hostlibs-y) $(hostlibs-m) $(hostlibs-) \ + $(hostcxxlibs-y) $(hostcxxlibs-m) + + __clean-files := $(filter-out $(no-clean-files), $(__clean-files)) +diff --git a/scripts/Makefile.host b/scripts/Makefile.host +index 3b7121d43324..2045855d0b75 100644 +--- a/scripts/Makefile.host ++++ b/scripts/Makefile.host +@@ -39,7 +39,6 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE + # They are linked as C++ code to the executable qconf + + __hostprogs := $(sort $(hostprogs)) +-host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m)) + host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m)) + + # C code +@@ -63,7 +62,6 @@ host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m))) + host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs))) + + # Object (.o) files used by the shared libaries +-host-cshobjs := $(sort $(foreach m,$(host-cshlib),$($(m:.so=-objs)))) + host-cxxshobjs := $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs)))) + + host-csingle := $(addprefix $(obj)/,$(host-csingle)) +@@ -71,9 +69,7 @@ host-cmulti := $(addprefix $(obj)/,$(host-cmulti)) + host-cobjs := $(addprefix $(obj)/,$(host-cobjs)) + host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti)) + host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs)) +-host-cshlib := $(addprefix $(obj)/,$(host-cshlib)) + host-cxxshlib := $(addprefix $(obj)/,$(host-cxxshlib)) +-host-cshobjs := $(addprefix $(obj)/,$(host-cshobjs)) + host-cxxshobjs := $(addprefix $(obj)/,$(host-cxxshobjs)) + + ##### +@@ -140,13 +136,6 @@ quiet_cmd_host-cxxobjs = HOSTCXX $@ + $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE + $(call if_changed_dep,host-cxxobjs) + +-# Compile .c file, create position independent .o file +-# host-cshobjs -> .o +-quiet_cmd_host-cshobjs = HOSTCC -fPIC $@ +- cmd_host-cshobjs = $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $< +-$(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE +- $(call if_changed_dep,host-cshobjs) +- + # Compile .c file, create position independent .o file + # Note that plugin capable gcc versions can be either C or C++ based + # therefore plugin source files have to be compilable in both C and C++ mode. +@@ -157,16 +146,6 @@ quiet_cmd_host-cxxshobjs = HOSTCXX -fPIC $@ + $(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE + $(call if_changed_dep,host-cxxshobjs) + +-# Link a shared library, based on position independent .o files +-# *.o -> .so shared library (host-cshlib) +-quiet_cmd_host-cshlib = HOSTLLD -shared $@ +- cmd_host-cshlib = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \ +- $(addprefix $(obj)/, $($(target-stem)-objs)) \ +- $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem).so) +-$(host-cshlib): FORCE +- $(call if_changed,host-cshlib) +-$(call multi_depend, $(host-cshlib), .so, -objs) +- + # Link a shared library, based on position independent .o files + # *.o -> .so shared library (host-cxxshlib) + quiet_cmd_host-cxxshlib = HOSTLLD -shared $@ +@@ -178,4 +157,4 @@ $(host-cxxshlib): FORCE + $(call multi_depend, $(host-cxxshlib), .so, -objs) + + targets += $(host-csingle) $(host-cmulti) $(host-cobjs)\ +- $(host-cxxmulti) $(host-cxxobjs) $(host-cshlib) $(host-cshobjs) $(host-cxxshlib) $(host-cxxshobjs) ++ $(host-cxxmulti) $(host-cxxobjs) $(host-cxxshlib) $(host-cxxshobjs) +diff --git a/scripts/gcc-plugin.sh b/scripts/gcc-plugin.sh +index d3caefe53eab..b79fd0bea838 100755 +--- a/scripts/gcc-plugin.sh ++++ b/scripts/gcc-plugin.sh +@@ -1,49 +1,14 @@ + #!/bin/sh + # SPDX-License-Identifier: GPL-2.0 +-srctree=$(dirname "$0") +- +-SHOW_ERROR= +-if [ "$1" = "--show-error" ] ; then +- SHOW_ERROR=1 +- shift || true +-fi +- +-gccplugins_dir=$($3 -print-file-name=plugin) +-plugincc=$($1 -E -x c++ - -o /dev/null -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF +-#include "gcc-common.h" +-#if BUILDING_GCC_VERSION >= 4008 || defined(ENABLE_BUILD_WITH_CXX) +-#warning $2 CXX +-#else +-#warning $1 CC +-#endif +-EOF +-) + +-if [ $? -ne 0 ] +-then +- if [ -n "$SHOW_ERROR" ] ; then +- echo "${plugincc}" >&2 +- fi +- exit 1 +-fi ++set -e + +-case "$plugincc" in +- *"$1 CC"*) +- echo "$1" +- exit 0 +- ;; +- +- *"$2 CXX"*) +- # the c++ compiler needs another test, see below +- ;; ++srctree=$(dirname "$0") + +- *) +- exit 1 +- ;; +-esac ++gccplugins_dir=$($* -print-file-name=plugin) + + # we need a c++ compiler that supports the designated initializer GNU extension +-plugincc=$($2 -c -x c++ -std=gnu++98 - -fsyntax-only -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF ++$HOSTCC -c -x c++ -std=gnu++98 - -fsyntax-only -I $srctree/gcc-plugins -I $gccplugins_dir/include 2>/dev/null <<EOF + #include "gcc-common.h" + class test { + public: +@@ -52,15 +17,3 @@ public: + .test = 1 + }; + EOF +-) +- +-if [ $? -eq 0 ] +-then +- echo "$2" +- exit 0 +-fi +- +-if [ -n "$SHOW_ERROR" ] ; then +- echo "${plugincc}" >&2 +-fi +-exit 1 +diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig +index e3569543bdac..fd31ed5b435f 100644 +--- a/scripts/gcc-plugins/Kconfig ++++ b/scripts/gcc-plugins/Kconfig +@@ -1,13 +1,4 @@ + # SPDX-License-Identifier: GPL-2.0-only +-preferred-plugin-hostcc := $(if-success,[ $(gcc-version) -ge 40800 ],$(HOSTCXX),$(HOSTCC)) +- +-config PLUGIN_HOSTCC +- string +- default "$(shell,$(srctree)/scripts/gcc-plugin.sh "$(preferred-plugin-hostcc)" "$(HOSTCXX)" "$(CC)")" if CC_IS_GCC +- help +- Host compiler used to build GCC plugins. This can be $(HOSTCXX), +- $(HOSTCC), or a null string if GCC plugin is unsupported. +- + config HAVE_GCC_PLUGINS + bool + help +@@ -17,7 +8,8 @@ config HAVE_GCC_PLUGINS + menuconfig GCC_PLUGINS + bool "GCC plugins" + depends on HAVE_GCC_PLUGINS +- depends on PLUGIN_HOSTCC != "" ++ depends on CC_IS_GCC && GCC_VERSION >= 40800 ++ depends on $(success,$(srctree)/scripts/gcc-plugin.sh $(CC)) + default y + help + GCC plugins are loadable modules that provide extra features to the +diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile +index f2ee8bd7abc6..f22858b2c3d6 100644 +--- a/scripts/gcc-plugins/Makefile ++++ b/scripts/gcc-plugins/Makefile +@@ -1,18 +1,9 @@ + # SPDX-License-Identifier: GPL-2.0 +-PLUGINCC := $(CONFIG_PLUGIN_HOSTCC:"%"=%) + GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin) + +-ifeq ($(PLUGINCC),$(HOSTCC)) +- HOSTLIBS := hostlibs +- HOST_EXTRACFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu99 -ggdb +- export HOST_EXTRACFLAGS +-else +- HOSTLIBS := hostcxxlibs +- HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti +- HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb +- HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable +- export HOST_EXTRACXXFLAGS +-endif ++HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti ++HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb ++HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat + + $(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h + quiet_cmd_create_randomize_layout_seed = GENSEED $@ +@@ -22,9 +13,9 @@ $(objtree)/$(obj)/randomize_layout_seed.h: FORCE + $(call if_changed,create_randomize_layout_seed) + targets = randomize_layout_seed.h randomize_layout_hash.h + +-$(HOSTLIBS)-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p))) +-always-y := $($(HOSTLIBS)-y) ++hostcxxlibs-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p))) ++always-y := $(hostcxxlibs-y) + +-$(foreach p,$($(HOSTLIBS)-y:%.so=%),$(eval $(p)-objs := $(p).o)) ++$(foreach p,$(hostcxxlibs-y:%.so=%),$(eval $(p)-objs := $(p).o)) + + clean-files += *.so +-- +2.26.2 + diff --git a/libre/linux-libre-pae/0003-gcc-common.h-Update-for-GCC-10.patch b/libre/linux-libre-pae/0003-gcc-common.h-Update-for-GCC-10.patch new file mode 100644 index 000000000..0abbdab45 --- /dev/null +++ b/libre/linux-libre-pae/0003-gcc-common.h-Update-for-GCC-10.patch @@ -0,0 +1,86 @@ +From fbe2e575df0f88daa156069cf66c3db0ebc64e7a Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20Pierret=20=28fepitre=29?= + <frederic.pierret@qubes-os.org> +Date: Tue, 7 Apr 2020 13:32:59 +0200 +Subject: [PATCH 3/5] gcc-common.h: Update for GCC 10 +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Remove "params.h" include, which has been dropped in GCC 10. + +Remove is_a_helper() macro, which is now defined in gimple.h, as seen +when running './scripts/gcc-plugin.sh g++ g++ gcc': + +In file included from <stdin>:1: +./gcc-plugins/gcc-common.h:852:13: error: redefinition of ‘static bool is_a_helper<T>::test(U*) [with U = const gimple; T = const ggoto*]’ + 852 | inline bool is_a_helper<const ggoto *>::test(const_gimple gs) + | ^~~~~~~~~~~~~~~~~~~~~~~~~~ +In file included from ./gcc-plugins/gcc-common.h:125, + from <stdin>:1: +/usr/lib/gcc/x86_64-redhat-linux/10/plugin/include/gimple.h:1037:1: note: ‘static bool is_a_helper<T>::test(U*) [with U = const gimple; T = const ggoto*]’ previously declared here + 1037 | is_a_helper <const ggoto *>::test (const gimple *gs) + | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Add -Wno-format-diag to scripts/gcc-plugins/Makefile to avoid +meaningless warnings from error() formats used by plugins: + +scripts/gcc-plugins/structleak_plugin.c: In function ‘int plugin_init(plugin_name_args*, plugin_gcc_version*)’: +scripts/gcc-plugins/structleak_plugin.c:253:12: warning: unquoted sequence of 2 consecutive punctuation characters ‘'-’ in format [-Wformat-diag] + 253 | error(G_("unknown option '-fplugin-arg-%s-%s'"), plugin_name, argv[i].key); + | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Signed-off-by: Frédéric Pierret (fepitre) <frederic.pierret@qubes-os.org> +Link: https://lore.kernel.org/r/20200407113259.270172-1-frederic.pierret@qubes-os.org +[kees: include -Wno-format-diag for plugin builds] +Signed-off-by: Kees Cook <keescook@chromium.org> +--- + scripts/gcc-plugins/Makefile | 1 + + scripts/gcc-plugins/gcc-common.h | 4 ++++ + 2 files changed, 5 insertions(+) + +diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile +index f22858b2c3d6..80f354289eeb 100644 +--- a/scripts/gcc-plugins/Makefile ++++ b/scripts/gcc-plugins/Makefile +@@ -4,6 +4,7 @@ GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin) + HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti + HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb + HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat ++HOST_EXTRACXXFLAGS += -Wno-format-diag + + $(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h + quiet_cmd_create_randomize_layout_seed = GENSEED $@ +diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h +index 17f06079a712..9ad76b7f3f10 100644 +--- a/scripts/gcc-plugins/gcc-common.h ++++ b/scripts/gcc-plugins/gcc-common.h +@@ -35,7 +35,9 @@ + #include "ggc.h" + #include "timevar.h" + ++#if BUILDING_GCC_VERSION < 10000 + #include "params.h" ++#endif + + #if BUILDING_GCC_VERSION <= 4009 + #include "pointer-set.h" +@@ -847,6 +849,7 @@ static inline gimple gimple_build_assign_with_ops(enum tree_code subcode, tree l + return gimple_build_assign(lhs, subcode, op1, op2 PASS_MEM_STAT); + } + ++#if BUILDING_GCC_VERSION < 10000 + template <> + template <> + inline bool is_a_helper<const ggoto *>::test(const_gimple gs) +@@ -860,6 +863,7 @@ inline bool is_a_helper<const greturn *>::test(const_gimple gs) + { + return gs->code == GIMPLE_RETURN; + } ++#endif + + static inline gasm *as_a_gasm(gimple stmt) + { +-- +2.26.2 + diff --git a/libre/linux-libre-pae/0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch b/libre/linux-libre-pae/0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch new file mode 100644 index 000000000..2b1914477 --- /dev/null +++ b/libre/linux-libre-pae/0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch @@ -0,0 +1,32 @@ +From e33336e058bdd4e109c9131bb13584ccb1b5e15d Mon Sep 17 00:00:00 2001 +From: Sergei Trofimovich <slyfox@gentoo.org> +Date: Tue, 17 Mar 2020 00:07:18 +0000 +Subject: [PATCH 4/5] Makefile: disallow data races on gcc-10 as well + +gcc-10 will rename --param=allow-store-data-races=0 +to -fno-allow-store-data-races. + +The flag change happened at https://gcc.gnu.org/PR92046. + +Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> +Acked-by: Jiri Kosina <jkosina@suse.cz> +Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> +--- + Makefile | 1 + + 1 file changed, 1 insertion(+) + +diff --git a/Makefile b/Makefile +index d252219666fd..abca59ecbe2b 100644 +--- a/Makefile ++++ b/Makefile +@@ -714,6 +714,7 @@ endif + + # Tell gcc to never replace conditional load with a non-conditional one + KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0) ++KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races) + + include scripts/Makefile.kcov + include scripts/Makefile.gcc-plugins +-- +2.26.2 + diff --git a/libre/linux-libre-pae/0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch b/libre/linux-libre-pae/0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch new file mode 100644 index 000000000..78505e790 --- /dev/null +++ b/libre/linux-libre-pae/0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch @@ -0,0 +1,131 @@ +From 53e90d763b7fe8bec6a0c86b6813131cd8e25026 Mon Sep 17 00:00:00 2001 +From: Borislav Petkov <bp@suse.de> +Date: Wed, 22 Apr 2020 18:11:30 +0200 +Subject: [PATCH 5/5] x86: Fix early boot crash on gcc-10, next try +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +... or the odyssey of trying to disable the stack protector for the +function which generates the stack canary value. + +The whole story started with Sergei reporting a boot crash with a kernel +built with gcc-10: + + Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary + CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 + Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 + Call Trace: + dump_stack + panic + ? start_secondary + __stack_chk_fail + start_secondary + secondary_startup_64 + -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary + +This happens because gcc-10 tail-call optimizes the last function call +in start_secondary() - cpu_startup_entry() - and thus emits a stack +canary check which fails because the canary value changes after the +boot_init_stack_canary() call. + +To fix that, the initial attempt was to mark the one function which +generates the stack canary with: + + __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) + +however, using the optimize attribute doesn't work cumulatively +as the attribute does not add to but rather replaces previously +supplied optimization options - roughly all -fxxx options. + +The key one among them being -fno-omit-frame-pointer and thus leading to +not present frame pointer - frame pointer which the kernel needs. + +The next attempt to prevent compilers from tail-call optimizing +the last function call cpu_startup_entry(), shy of carving out +start_secondary() into a separate compilation unit and building it with +-fno-stack-protector, is this one. + +The current solution is short and sweet, and reportedly, is supported by +both compilers so let's see how far we'll get this time. + +Reported-by: Sergei Trofimovich <slyfox@gentoo.org> +Signed-off-by: Borislav Petkov <bp@suse.de> +Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> +Reviewed-by: Kees Cook <keescook@chromium.org> +Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org +--- + arch/x86/include/asm/stackprotector.h | 7 ++++++- + arch/x86/kernel/smpboot.c | 8 ++++++++ + arch/x86/xen/smp_pv.c | 1 + + include/linux/compiler.h | 6 ++++++ + 4 files changed, 21 insertions(+), 1 deletion(-) + +diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h +index 91e29b6a86a5..9804a7957f4e 100644 +--- a/arch/x86/include/asm/stackprotector.h ++++ b/arch/x86/include/asm/stackprotector.h +@@ -55,8 +55,13 @@ + /* + * Initialize the stackprotector canary value. + * +- * NOTE: this must only be called from functions that never return, ++ * NOTE: this must only be called from functions that never return + * and it must always be inlined. ++ * ++ * In addition, it should be called from a compilation unit for which ++ * stack protector is disabled. Alternatively, the caller should not end ++ * with a function call which gets tail-call optimized as that would ++ * lead to checking a modified canary value. + */ + static __always_inline void boot_init_stack_canary(void) + { +diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c +index 69881b2d446c..9674321ce3a3 100644 +--- a/arch/x86/kernel/smpboot.c ++++ b/arch/x86/kernel/smpboot.c +@@ -262,6 +262,14 @@ static void notrace start_secondary(void *unused) + + wmb(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ ++ /* ++ * Prevent tail call to cpu_startup_entry() because the stack protector ++ * guard has been changed a couple of function calls up, in ++ * boot_init_stack_canary() and must not be checked before tail calling ++ * another function. ++ */ ++ prevent_tail_call_optimization(); + } + + /** +diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c +index 802ee5bba66c..0cebe5db691d 100644 +--- a/arch/x86/xen/smp_pv.c ++++ b/arch/x86/xen/smp_pv.c +@@ -92,6 +92,7 @@ asmlinkage __visible void cpu_bringup_and_idle(void) + cpu_bringup(); + boot_init_stack_canary(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); ++ prevent_tail_call_optimization(); + } + + void xen_smp_intr_free_pv(unsigned int cpu) +diff --git a/include/linux/compiler.h b/include/linux/compiler.h +index 034b0a644efc..732754d96039 100644 +--- a/include/linux/compiler.h ++++ b/include/linux/compiler.h +@@ -356,4 +356,10 @@ static inline void *offset_to_ptr(const int *off) + /* &a[0] degrades to a pointer: a different type from an array */ + #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) + ++/* ++ * This is needed in functions which generate the stack canary, see ++ * arch/x86/kernel/smpboot.c::start_secondary() for an example. ++ */ ++#define prevent_tail_call_optimization() asm("") ++ + #endif /* __LINUX_COMPILER_H */ +-- +2.26.2 + diff --git a/libre/linux-libre-pae/PKGBUILD b/libre/linux-libre-pae/PKGBUILD index f402bdc2a..e10ed4d63 100644 --- a/libre/linux-libre-pae/PKGBUILD +++ b/libre/linux-libre-pae/PKGBUILD @@ -9,7 +9,7 @@ _replacesoldkernels=() # '%' gets replaced with kernel suffix _replacesoldmodules=() # '%' gets replaced with kernel suffix pkgbase=linux-libre-pae -pkgver=5.6.7 +pkgver=5.6.13 pkgrel=1 pkgdesc='Linux-libre PAE (physical address extension)' url='https://linux-libre.fsfla.org/' @@ -35,8 +35,12 @@ source=( # https://labs.parabola.nu/issues/877 # http://www.fsfla.org/pipermail/linux-libre/2015-November/003202.html 0002-fix-Atmel-maXTouch-touchscreen-support.patch - # extracted patches from Arch Linux kernel sources + # Arch Linux patches 0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch + 0002-gcc-plugins-drop-support-for-GCC-4.7.patch + 0003-gcc-common.h-Update-for-GCC-10.patch + 0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch + 0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch sphinx-workaround.patch ) validpgpkeys=( @@ -45,7 +49,7 @@ validpgpkeys=( ) sha512sums=('df473a228ca2bbefbcc630aee710c78c83083269b4939adf698a9adf3a5760391b24529704bfc0b108bc67054ebed047746810e1b41be1fd9019a911a563114d' 'SKIP' - '0c01eabfbd10fb5aeabcb60c9ca362576bd7b33a31b841704b3b4d3c650a2a681b208ffdeb82673286b0e8449858d399cc80f04acafa7d27ee686f2880471e6d' + '913c307a2dd5509d8b559223e7f4dc3e800a5030b7d401db661617a781d849a8627f09ced8e825dd0222758ef4976994d214c40b2e5eaa5f30864597859c9fb7' 'SKIP' '13cb5bc42542e7b8bb104d5f68253f6609e463b6799800418af33eb0272cc269aaa36163c3e6f0aacbdaaa1d05e2827a4a7c4a08a029238439ed08b89c564bb3' 'SKIP' @@ -56,7 +60,11 @@ sha512sums=('df473a228ca2bbefbcc630aee710c78c83083269b4939adf698a9adf3a5760391b2 '87bc57f79ee284f592951c866b9d90de3caa543456412fe308a0f1b7cb9528ee27c9dad0fbb4330b0cfaf6d783f5ad4996eae7ce44345dfc47ef64059270dd38' '02af4dd2a007e41db0c63822c8ab3b80b5d25646af1906dc85d0ad9bb8bbf5236f8e381d7f91cf99ed4b0978c50aee37cb9567cdeef65b7ec3d91b882852b1af' 'b8fe56e14006ab866970ddbd501c054ae37186ddc065bb869cf7d18db8c0d455118d5bda3255fb66a0dde38b544655cfe9040ffe46e41d19830b47959b2fb168' - 'f340f8beaf2df0970ed592360da8d625ba6be27ed4a0773ff8a6b5dc638b0e7b73e575d3e154c328999dfe9ebf4f18739adade8ddfa89472845318885f9da1c0' + 'ee11227b513e63ad45902c273dc7f258bb033140d5161b70aa6dfb025a1bd956ca40e1512eab95e2d2e40d0c762c3e6f290961f75b86d238021e8f6a9e64ea61' + '063168ed84fae0a3f84da59dcc1b37b8d2c851a45026815976a8c9bc4290a06f912d40d5f271f8033cb9ec31754fe5d8f2a7a28cece1fd94e78e3415ceea645a' + 'b78eba89d46a9ac67ff64cf208e2310b56fc187a659848bd0b10db045d4bec08574d526663eadcea5d0c3991638db7824baea1c272da6c07aa0b949bc9ec71b1' + '098c06e3e6cf20e845244f0ec4c58cc94b9f916f8b8d9f5ec1acbd77707048f5e3d65845a26ba79d5d3f4f238a8e3ff0be199f43ab2cce7b057e57b64b5243f4' + '606dfa4481b253c6a163ef9b50a24af494088663e4c82d48fc0a5c3fde85fa7102ef52a826e1426d7f59037e17ce6a3fd811d60aeffd4d396cb5d94d2078e940' '98e97155f86bbe837d43f27ec1018b5b6fdc6c372d6f7f2a0fe29da117d53979d9f9c262f886850d92002898682781029b80d4ee923633fc068f979e6c8254be') _replacesarchkernel=("${_replacesarchkernel[@]/\%/${pkgbase#linux-libre}}") @@ -112,7 +120,8 @@ _package() { depends=(coreutils kmod initramfs) optdepends=('crda: to set the correct wireless channels of your country' 'linux-libre-firmware: firmware images needed for some devices') - provides=("${_replacesarchkernel[@]/%/=${pkgver%%_*}}" "LINUX-ABI_VERSION=${pkgver%%_*}") + provides=(VIRTUALBOX-GUEST-MODULES WIREGUARD-MODULE) + provides+=("${_replacesarchkernel[@]/%/=${pkgver%.*}}" "LINUX-ABI_VERSION=${pkgver%.*}") conflicts=("${_replacesarchkernel[@]}" "${_replacesoldkernels[@]}" "${_replacesoldmodules[@]}") replaces=("${_replacesarchkernel[@]}" "${_replacesoldkernels[@]}" "${_replacesoldmodules[@]}") |