From 65120498aaf8d7320647a8b6d6de7db42e74ea52 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 8 Nov 2023 13:58:27 +0100 Subject: stackleak: add declarations for global functions With -Wmissing-prototypes enabled, the stackleak code produces a couple of warnings that have no declarations because they are only called from assembler: stackleak.c:127:25: error: no previous prototype for 'stackleak_erase' [-Werror=missing-prototypes] stackleak.c:139:25: error: no previous prototype for 'stackleak_erase_on_task_stack' [-Werror=missing-prototypes] stackleak.c:151:25: error: no previous prototype for 'stackleak_erase_off_task_stack' [-Werror=missing-prototypes] stackleak.c:159:49: error: no previous prototype for 'stackleak_track_stack' [-Werror=missing-prototypes] Add declarations to the stackleak header to shut up the warnings. Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20231108125843.3806765-7-arnd@kernel.org Signed-off-by: Kees Cook --- include/linux/stackleak.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/include/linux/stackleak.h b/include/linux/stackleak.h index c36e7a3b45e7..3be2cb564710 100644 --- a/include/linux/stackleak.h +++ b/include/linux/stackleak.h @@ -14,6 +14,7 @@ #ifdef CONFIG_GCC_PLUGIN_STACKLEAK #include +#include /* * The lowest address on tsk's stack which we can plausibly erase. @@ -76,6 +77,11 @@ static inline void stackleak_task_init(struct task_struct *t) # endif } +asmlinkage void noinstr stackleak_erase(void); +asmlinkage void noinstr stackleak_erase_on_task_stack(void); +asmlinkage void noinstr stackleak_erase_off_task_stack(void); +void __no_caller_saved_registers noinstr stackleak_track_stack(void); + #else /* !CONFIG_GCC_PLUGIN_STACKLEAK */ static inline void stackleak_task_init(struct task_struct *t) { } #endif -- cgit v1.2.3 From 1ee60356c2dca938362528404af95b8ef3e49b6a Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sat, 4 Nov 2023 13:43:37 -0700 Subject: gcc-plugins: randstruct: Only warn about true flexible arrays The randstruct GCC plugin tried to discover "fake" flexible arrays to issue warnings about them in randomized structs. In the future LSM overhead reduction series, it would be legal to have a randomized struct with a 1-element array, and this should _not_ be treated as a flexible array, especially since commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3"). Disable the 0-sized and 1-element array discovery logic in the plugin, but keep the "true" flexible array check. Cc: KP Singh Cc: linux-hardening@vger.kernel.org Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202311021532.iBwuZUZ0-lkp@intel.com/ Fixes: df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") Reviewed-by: Bill Wendling Acked-by: "Gustavo A. R. Silva" Link: https://lore.kernel.org/r/20231104204334.work.160-kees@kernel.org Signed-off-by: Kees Cook --- scripts/gcc-plugins/randomize_layout_plugin.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 366395cab490..910bd21d08f4 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -278,8 +278,6 @@ static bool is_flexible_array(const_tree field) { const_tree fieldtype; const_tree typesize; - const_tree elemtype; - const_tree elemsize; fieldtype = TREE_TYPE(field); typesize = TYPE_SIZE(fieldtype); @@ -287,20 +285,12 @@ static bool is_flexible_array(const_tree field) if (TREE_CODE(fieldtype) != ARRAY_TYPE) return false; - elemtype = TREE_TYPE(fieldtype); - elemsize = TYPE_SIZE(elemtype); - /* size of type is represented in bits */ if (typesize == NULL_TREE && TYPE_DOMAIN(fieldtype) != NULL_TREE && TYPE_MAX_VALUE(TYPE_DOMAIN(fieldtype)) == NULL_TREE) return true; - if (typesize != NULL_TREE && - (TREE_CONSTANT(typesize) && (!tree_to_uhwi(typesize) || - tree_to_uhwi(typesize) == tree_to_uhwi(elemsize)))) - return true; - return false; } -- cgit v1.2.3 From 782ce431613cf08c3a00dca42ad925c3b1108d09 Mon Sep 17 00:00:00 2001 From: Konstantin Runov Date: Mon, 30 Oct 2023 12:45:08 +0300 Subject: gcc-plugins: latent_entropy: Fix typo (args -> argc) in plugin description Fix the typo in the plugin description comment. Clearly, "argc" should be used. Signed-off-by: Konstantin Runov Link: https://lore.kernel.org/r/20231030094508.245432-1-runebone1@gmail.com Signed-off-by: Kees Cook --- scripts/gcc-plugins/latent_entropy_plugin.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/gcc-plugins/latent_entropy_plugin.c b/scripts/gcc-plugins/latent_entropy_plugin.c index 39e86be60dd2..ff0b192be91f 100644 --- a/scripts/gcc-plugins/latent_entropy_plugin.c +++ b/scripts/gcc-plugins/latent_entropy_plugin.c @@ -17,7 +17,7 @@ * if (argc <= 1) * printf("%s: no command arguments :(\n", *argv); * else - * printf("%s: %d command arguments!\n", *argv, args - 1); + * printf("%s: %d command arguments!\n", *argv, argc - 1); * } * * after: @@ -47,7 +47,7 @@ * // perturb_local_entropy() * } else { * local_entropy ^= 3896280633962944730; - * printf("%s: %d command arguments!\n", *argv, args - 1); + * printf("%s: %d command arguments!\n", *argv, argc - 1); * } * * // latent_entropy_execute() 4. -- cgit v1.2.3