user/sven/linux.git/scripts/gcc-plugins, branch v5.4.227

gcc-plugins: latent_entropy: use /dev/urandom

2022-04-20T07:19:38Z

commit c40160f2998c897231f8454bf797558d30a20375 upstream. While the latent entropy plugin mostly doesn't derive entropy from get_random_const() for measuring the call graph, when __latent_entropy is applied to a constant, then it's initialized statically to output from get_random_const(). In that case, this data is derived from a 64-bit seed, which means a buffer of 512 bits doesn't really have that amount of compile-time entropy. This patch fixes that shortcoming by just buffering chunks of /dev/urandom output and doling it out as requested. At the same time, it's important that we don't break the use of -frandom-seed, for people who want the runtime benefits of the latent entropy plugin, while still having compile-time determinism. In that case, we detect whether gcc's set_random_seed() has been called by making a call to get_random_seed(noinit=true) in the plugin init function, which is called after set_random_seed() is called but before anything that calls get_random_seed(noinit=false), and seeing if it's zero or not. If it's not zero, we're in deterministic mode, and so we just generate numbers with a basic xorshift prng. Note that we don't detect if -frandom-seed is being used using the documented local_tick variable, because it's assigned via: local_tick = (unsigned) tv.tv_sec * 1000 + tv.tv_usec / 1000; which may well overflow and become -1 on its own, and so isn't reliable: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105171 [kees: The 256 byte rnd_buf size was chosen based on average (250), median (64), and std deviation (575) bytes of used entropy for a defconfig x86_64 build] Fixes: 38addce8b600 ("gcc-plugins: Add latent_entropy plugin") Cc: stable@vger.kernel.org Cc: PaX Team Signed-off-by: Jason A. Donenfeld Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220405222815.21155-1-Jason@zx2c4.com Signed-off-by: Greg Kroah-Hartman

gcc-plugins/stackleak: Exactly match strings instead of prefixes

2022-04-15T12:18:22Z

[ Upstream commit 27e9faf415dbf94af19b9c827842435edbc1fbbc ] Since STRING_CST may not be NUL terminated, strncmp() was used for check for equality. However, this may lead to mismatches for longer section names where the start matches the tested-for string. Test for exact equality by checking for the presences of NUL termination. Cc: Alexander Popov Signed-off-by: Kees Cook Signed-off-by: Sasha Levin

gcc-common.h: Update for GCC 10

2020-05-27T15:46:24Z

[ Upstream commit c7527373fe28f97d8a196ab562db5589be0d34b9 ] 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 :1: ./gcc-plugins/gcc-common.h:852:13: error: redefinition of ‘static bool is_a_helper::test(U*) [with U = const gimple; T = const ggoto*]’ 852 | inline bool is_a_helper::test(const_gimple gs) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from ./gcc-plugins/gcc-common.h:125, from :1: /usr/lib/gcc/x86_64-redhat-linux/10/plugin/include/gimple.h:1037:1: note: ‘static bool is_a_helper::test(U*) [with U = const gimple; T = const ggoto*]’ previously declared here 1037 | is_a_helper ::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) 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 Signed-off-by: Sasha Levin

gcc-plugins: make it possible to disable CONFIG_GCC_PLUGINS again

2020-01-09T09:19:57Z

commit a5b0dc5a46c221725c43bd9b01570239a4cd78b1 upstream. I noticed that randconfig builds with gcc no longer produce a lot of ccache hits, unlike with clang, and traced this back to plugins now being enabled unconditionally if they are supported. I am now working around this by adding export CCACHE_COMPILERCHECK=/usr/bin/size -A %compiler% to my top-level Makefile. This changes the heuristic that ccache uses to determine whether the plugins are the same after a 'make clean'. However, it also seems that being able to just turn off the plugins is generally useful, at least for build testing it adds noticeable overhead but does not find a lot of bugs additional bugs, and may be easier for ccache users than my workaround. Fixes: 9f671e58159a ("security: Create "kernel hardening" config area") Signed-off-by: Arnd Bergmann Acked-by: Ard Biesheuvel Reviewed-by: Masahiro Yamada Link: https://lore.kernel.org/r/20191211133951.401933-1-arnd@arndb.de Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman

randstruct: Check member structs in is_pure_ops_struct()

2019-07-31T20:13:22Z

While no uses in the kernel triggered this case, it was possible to have a false negative where a struct contains other structs which contain only function pointers because of unreachable code in is_pure_ops_struct(). Signed-off-by: Joonwon Kang Link: https://lore.kernel.org/r/20190727155841.GA13586@host Fixes: 313dd1b62921 ("gcc-plugins: Add the randstruct plugin") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook

docs: move gcc_plugins.txt to core-api and rename to .rst

2019-07-15T12:20:27Z

The gcc_plugins.txt file is already a ReST file. Move it to the core-api book while renaming it. Signed-off-by: Mauro Carvalho Chehab Acked-by: Kees Cook

Merge tag 'gcc-plugins-v5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2019-05-31T17:26:05Z

Pull gcc-plugins fix from Kees Cook: "Handle unusual header environment, fixing a redefined macro error under a Darwin build host" * tag 'gcc-plugins-v5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: gcc-plugins: Fix build failures under Darwin host

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46Z

Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

gcc-plugins: Fix build failures under Darwin host

2019-05-20T20:30:54Z

The gcc-common.h file did not take into account certain macros that might have already been defined in the build environment. This updates the header to avoid redefining the macros, as seen on a Darwin host using gcc 4.9.2: HOSTCXX -fPIC scripts/gcc-plugins/arm_ssp_per_task_plugin.o - due to: scripts/gcc-plugins/gcc-common.h In file included from scripts/gcc-plugins/arm_ssp_per_task_plugin.c:3:0: scripts/gcc-plugins/gcc-common.h:153:0: warning: "__unused" redefined ^ In file included from /usr/include/stdio.h:64:0, from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/system.h:40, from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/gcc-plugin.h:28, from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/plugin.h:23, from scripts/gcc-plugins/gcc-common.h:9, from scripts/gcc-plugins/arm_ssp_per_task_plugin.c:3: /usr/include/sys/cdefs.h:161:0: note: this is the location of the previous definition ^ Reported-and-tested-by: "H. Nikolaus Schaller" Fixes: 189af4657186 ("ARM: smp: add support for per-task stack canaries") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook

Merge tag 'gcc-plugins-v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/kees/linux

2019-05-13T23:01:52Z

Pull gcc plugin fix from Kees Cook: "Fix ARM stack-protector-per-task plugin build for older GCC < 6 (Chris Packham)" * tag 'gcc-plugins-v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/kees/linux: gcc-plugins: arm_ssp_per_task_plugin: Fix for older GCC < 6