From ad21fc4faa2a1f919bac1073b885df9310dbc581 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Mon, 6 Feb 2017 16:31:57 -0800 Subject: arch: Move CONFIG_DEBUG_RODATA and CONFIG_SET_MODULE_RONX to be common There are multiple architectures that support CONFIG_DEBUG_RODATA and CONFIG_SET_MODULE_RONX. These options also now have the ability to be turned off at runtime. Move these to an architecture independent location and make these options def_bool y for almost all of those arches. Signed-off-by: Laura Abbott Acked-by: Ingo Molnar Acked-by: Heiko Carstens Signed-off-by: Kees Cook --- Documentation/security/self-protection.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation/security') diff --git a/Documentation/security/self-protection.txt b/Documentation/security/self-protection.txt index 3010576c9fca..f41dd00e8b98 100644 --- a/Documentation/security/self-protection.txt +++ b/Documentation/security/self-protection.txt @@ -56,6 +56,12 @@ CONFIG_DEBUG_SET_MODULE_RONX, which seek to make sure that code is not writable, data is not executable, and read-only data is neither writable nor executable. +Most architectures have these options on by default and not user selectable. +For some architectures like arm that wish to have these be selectable, +the architecture Kconfig can select ARCH_OPTIONAL_KERNEL_RWX to enable +a Kconfig prompt. CONFIG_ARCH_OPTIONAL_KERNEL_RWX_DEFAULT determines +the default setting when ARCH_OPTIONAL_KERNEL_RWX is enabled. + #### Function pointers and sensitive variables must not be writable Vast areas of kernel memory contain function pointers that are looked -- cgit v1.2.3 From 0f5bf6d0afe4be6e1391908ff2d6dc9730e91550 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Mon, 6 Feb 2017 16:31:58 -0800 Subject: arch: Rename CONFIG_DEBUG_RODATA and CONFIG_DEBUG_MODULE_RONX Both of these options are poorly named. The features they provide are necessary for system security and should not be considered debug only. Change the names to CONFIG_STRICT_KERNEL_RWX and CONFIG_STRICT_MODULE_RWX to better describe what these options do. Signed-off-by: Laura Abbott Acked-by: Jessica Yu Signed-off-by: Kees Cook --- Documentation/DocBook/kgdb.tmpl | 8 ++++---- Documentation/security/self-protection.txt | 4 ++-- arch/Kconfig | 4 ++-- arch/arm/configs/aspeed_g4_defconfig | 4 ++-- arch/arm/configs/aspeed_g5_defconfig | 4 ++-- arch/arm/include/asm/cacheflush.h | 2 +- arch/arm/kernel/patch.c | 4 ++-- arch/arm/kernel/vmlinux.lds.S | 8 ++++---- arch/arm/mm/Kconfig | 2 +- arch/arm/mm/init.c | 4 ++-- arch/arm64/Kconfig.debug | 2 +- arch/arm64/kernel/insn.c | 2 +- arch/parisc/configs/712_defconfig | 1 - arch/parisc/configs/c3000_defconfig | 1 - arch/parisc/mm/init.c | 2 +- include/linux/filter.h | 4 ++-- include/linux/init.h | 4 ++-- include/linux/module.h | 2 +- init/main.c | 4 ++-- kernel/configs/android-recommended.config | 2 +- kernel/module.c | 6 +++--- kernel/power/hibernate.c | 2 +- kernel/power/power.h | 4 ++-- kernel/power/snapshot.c | 4 ++-- 24 files changed, 41 insertions(+), 43 deletions(-) (limited to 'Documentation/security') diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl index f3abca7ec53d..856ac20bf367 100644 --- a/Documentation/DocBook/kgdb.tmpl +++ b/Documentation/DocBook/kgdb.tmpl @@ -115,12 +115,12 @@ If the architecture that you are using supports the kernel option - CONFIG_DEBUG_RODATA, you should consider turning it off. This + CONFIG_STRICT_KERNEL_RWX, you should consider turning it off. This option will prevent the use of software breakpoints because it marks certain regions of the kernel's memory space as read-only. If kgdb supports it for the architecture you are using, you can use hardware breakpoints if you desire to run with the - CONFIG_DEBUG_RODATA option turned on, else you need to turn off + CONFIG_STRICT_KERNEL_RWX option turned on, else you need to turn off this option. @@ -135,7 +135,7 @@ Here is an example set of .config symbols to enable or disable for kgdb: - # CONFIG_DEBUG_RODATA is not set + # CONFIG_STRICT_KERNEL_RWX is not set CONFIG_FRAME_POINTER=y CONFIG_KGDB=y CONFIG_KGDB_SERIAL_CONSOLE=y @@ -166,7 +166,7 @@ Here is an example set of .config symbols to enable/disable kdb: - # CONFIG_DEBUG_RODATA is not set + # CONFIG_STRICT_KERNEL_RWX is not set CONFIG_FRAME_POINTER=y CONFIG_KGDB=y CONFIG_KGDB_SERIAL_CONSOLE=y diff --git a/Documentation/security/self-protection.txt b/Documentation/security/self-protection.txt index f41dd00e8b98..141acfebe6ef 100644 --- a/Documentation/security/self-protection.txt +++ b/Documentation/security/self-protection.txt @@ -51,8 +51,8 @@ kernel, they are implemented in a way where the memory is temporarily made writable during the update, and then returned to the original permissions.) -In support of this are (the poorly named) CONFIG_DEBUG_RODATA and -CONFIG_DEBUG_SET_MODULE_RONX, which seek to make sure that code is not +In support of this are CONFIG_STRICT_KERNEL_RWX and +CONFIG_STRICT_MODULE_RWX, which seek to make sure that code is not writable, data is not executable, and read-only data is neither writable nor executable. diff --git a/arch/Kconfig b/arch/Kconfig index 3f8b8be3036f..33f5a555c32a 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -790,7 +790,7 @@ config ARCH_OPTIONAL_KERNEL_RWX_DEFAULT config ARCH_HAS_STRICT_KERNEL_RWX def_bool n -config DEBUG_RODATA +config STRICT_KERNEL_RWX bool "Make kernel text and rodata read-only" if ARCH_OPTIONAL_KERNEL_RWX depends on ARCH_HAS_STRICT_KERNEL_RWX default !ARCH_OPTIONAL_KERNEL_RWX || ARCH_OPTIONAL_KERNEL_RWX_DEFAULT @@ -806,7 +806,7 @@ config DEBUG_RODATA config ARCH_HAS_STRICT_MODULE_RWX def_bool n -config DEBUG_SET_MODULE_RONX +config STRICT_MODULE_RWX bool "Set loadable kernel module data as NX and text as RO" if ARCH_OPTIONAL_KERNEL_RWX depends on ARCH_HAS_STRICT_MODULE_RWX && MODULES default !ARCH_OPTIONAL_KERNEL_RWX || ARCH_OPTIONAL_KERNEL_RWX_DEFAULT diff --git a/arch/arm/configs/aspeed_g4_defconfig b/arch/arm/configs/aspeed_g4_defconfig index ca39c04fec6b..05b99bc1c1ce 100644 --- a/arch/arm/configs/aspeed_g4_defconfig +++ b/arch/arm/configs/aspeed_g4_defconfig @@ -25,7 +25,6 @@ CONFIG_MODULE_UNLOAD=y # CONFIG_ARCH_MULTI_V7 is not set CONFIG_ARCH_ASPEED=y CONFIG_MACH_ASPEED_G4=y -CONFIG_DEBUG_RODATA=y CONFIG_AEABI=y CONFIG_UACCESS_WITH_MEMCPY=y CONFIG_SECCOMP=y @@ -79,7 +78,8 @@ CONFIG_DEBUG_LL_UART_8250=y CONFIG_DEBUG_UART_PHYS=0x1e784000 CONFIG_DEBUG_UART_VIRT=0xe8784000 CONFIG_EARLY_PRINTK=y -CONFIG_DEBUG_SET_MODULE_RONX=y +CONFIG_STRICT_MODULE_RWX=y +CONFIG_STRICT_KERNEL_RWX=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set # CONFIG_XZ_DEC_IA64 is not set diff --git a/arch/arm/configs/aspeed_g5_defconfig b/arch/arm/configs/aspeed_g5_defconfig index 4f366b0370e9..05a16d53d03c 100644 --- a/arch/arm/configs/aspeed_g5_defconfig +++ b/arch/arm/configs/aspeed_g5_defconfig @@ -26,7 +26,6 @@ CONFIG_ARCH_MULTI_V6=y # CONFIG_ARCH_MULTI_V7 is not set CONFIG_ARCH_ASPEED=y CONFIG_MACH_ASPEED_G5=y -CONFIG_DEBUG_RODATA=y CONFIG_AEABI=y CONFIG_UACCESS_WITH_MEMCPY=y CONFIG_SECCOMP=y @@ -81,7 +80,8 @@ CONFIG_DEBUG_LL_UART_8250=y CONFIG_DEBUG_UART_PHYS=0x1e784000 CONFIG_DEBUG_UART_VIRT=0xe8784000 CONFIG_EARLY_PRINTK=y -CONFIG_DEBUG_SET_MODULE_RONX=y +CONFIG_STRICT_MODULE_RWX=y +CONFIG_STRICT_KERNEL_RWX=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set # CONFIG_XZ_DEC_IA64 is not set diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h index bdd283bc5842..02454fa15d2c 100644 --- a/arch/arm/include/asm/cacheflush.h +++ b/arch/arm/include/asm/cacheflush.h @@ -490,7 +490,7 @@ static inline int set_memory_x(unsigned long addr, int numpages) { return 0; } static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; } #endif -#ifdef CONFIG_DEBUG_RODATA +#ifdef CONFIG_STRICT_KERNEL_RWX void set_kernel_text_rw(void); void set_kernel_text_ro(void); #else diff --git a/arch/arm/kernel/patch.c b/arch/arm/kernel/patch.c index 69bda1a5707e..020560b2dcb7 100644 --- a/arch/arm/kernel/patch.c +++ b/arch/arm/kernel/patch.c @@ -24,9 +24,9 @@ static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags) bool module = !core_kernel_text(uintaddr); struct page *page; - if (module && IS_ENABLED(CONFIG_DEBUG_SET_MODULE_RONX)) + if (module && IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) page = vmalloc_to_page(addr); - else if (!module && IS_ENABLED(CONFIG_DEBUG_RODATA)) + else if (!module && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) page = virt_to_page(addr); else return addr; diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index f7f55df0bf7b..ce18007f9e4e 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -97,7 +97,7 @@ SECTIONS HEAD_TEXT } -#ifdef CONFIG_DEBUG_RODATA +#ifdef CONFIG_STRICT_KERNEL_RWX . = ALIGN(1<len * sizeof(fprog->filter[0])) -#ifdef CONFIG_DEBUG_SET_MODULE_RONX +#ifdef CONFIG_STRICT_MODULE_RWX static inline void bpf_prog_lock_ro(struct bpf_prog *fp) { set_memory_ro((unsigned long)fp, fp->pages); @@ -561,7 +561,7 @@ static inline void bpf_prog_lock_ro(struct bpf_prog *fp) static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) { } -#endif /* CONFIG_DEBUG_SET_MODULE_RONX */ +#endif /* CONFIG_STRICT_MODULE_RWX */ int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); static inline int sk_filter(struct sock *sk, struct sk_buff *skb) diff --git a/include/linux/init.h b/include/linux/init.h index 885c3e6d0f9d..79af0962fd52 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -126,10 +126,10 @@ void prepare_namespace(void); void __init load_default_modules(void); int __init init_rootfs(void); -#if defined(CONFIG_DEBUG_RODATA) || defined(CONFIG_DEBUG_SET_MODULE_RONX) +#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) extern bool rodata_enabled; #endif -#ifdef CONFIG_DEBUG_RODATA +#ifdef CONFIG_STRICT_KERNEL_RWX void mark_rodata_ro(void); #endif diff --git a/include/linux/module.h b/include/linux/module.h index 7c84273d60b9..d5afd142818f 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -764,7 +764,7 @@ extern int module_sysfs_initialized; #define __MODULE_STRING(x) __stringify(x) -#ifdef CONFIG_DEBUG_SET_MODULE_RONX +#ifdef CONFIG_STRICT_MODULE_RWX extern void set_all_modules_text_rw(void); extern void set_all_modules_text_ro(void); extern void module_enable_ro(const struct module *mod, bool after_init); diff --git a/init/main.c b/init/main.c index b0c9d6facef9..0b7bae29eef6 100644 --- a/init/main.c +++ b/init/main.c @@ -925,7 +925,7 @@ static int try_to_run_init_process(const char *init_filename) static noinline void __init kernel_init_freeable(void); -#if defined(CONFIG_DEBUG_RODATA) || defined(CONFIG_DEBUG_SET_MODULE_RONX) +#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX) bool rodata_enabled __ro_after_init = true; static int __init set_debug_rodata(char *str) { @@ -934,7 +934,7 @@ static int __init set_debug_rodata(char *str) __setup("rodata=", set_debug_rodata); #endif -#ifdef CONFIG_DEBUG_RODATA +#ifdef CONFIG_STRICT_KERNEL_RWX static void mark_readonly(void) { if (rodata_enabled) diff --git a/kernel/configs/android-recommended.config b/kernel/configs/android-recommended.config index 297756be369c..99127edc5204 100644 --- a/kernel/configs/android-recommended.config +++ b/kernel/configs/android-recommended.config @@ -11,7 +11,7 @@ CONFIG_BLK_DEV_LOOP=y CONFIG_BLK_DEV_RAM=y CONFIG_BLK_DEV_RAM_SIZE=8192 CONFIG_COMPACTION=y -CONFIG_DEBUG_RODATA=y +CONFIG_STRICT_KERNEL_RWX=y CONFIG_DM_CRYPT=y CONFIG_DM_UEVENT=y CONFIG_DM_VERITY=y diff --git a/kernel/module.c b/kernel/module.c index 5088784c0cf9..e71478569273 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -74,9 +74,9 @@ /* * Modules' sections will be aligned on page boundaries * to ensure complete separation of code and data, but - * only when CONFIG_DEBUG_SET_MODULE_RONX=y + * only when CONFIG_STRICT_MODULE_RWX=y */ -#ifdef CONFIG_DEBUG_SET_MODULE_RONX +#ifdef CONFIG_STRICT_MODULE_RWX # define debug_align(X) ALIGN(X, PAGE_SIZE) #else # define debug_align(X) (X) @@ -1847,7 +1847,7 @@ static void mod_sysfs_teardown(struct module *mod) mod_sysfs_fini(mod); } -#ifdef CONFIG_DEBUG_SET_MODULE_RONX +#ifdef CONFIG_STRICT_MODULE_RWX /* * LKM RO/NX protection: protect module's text/ro-data * from modification and any data from execution. diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index b26dbc48c75b..86385af1080f 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -1156,7 +1156,7 @@ static int __init hibernate_setup(char *str) } else if (!strncmp(str, "no", 2)) { noresume = 1; nohibernate = 1; - } else if (IS_ENABLED(CONFIG_DEBUG_RODATA) + } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && !strncmp(str, "protect_image", 13)) { enable_restore_image_protection(); } diff --git a/kernel/power/power.h b/kernel/power/power.h index 1dfa0da827d3..7fdc40d31b7d 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -61,12 +61,12 @@ extern int hibernation_snapshot(int platform_mode); extern int hibernation_restore(int platform_mode); extern int hibernation_platform_enter(void); -#ifdef CONFIG_DEBUG_RODATA +#ifdef CONFIG_STRICT_KERNEL_RWX /* kernel/power/snapshot.c */ extern void enable_restore_image_protection(void); #else static inline void enable_restore_image_protection(void) {} -#endif /* CONFIG_DEBUG_RODATA */ +#endif /* CONFIG_STRICT_KERNEL_RWX */ #else /* !CONFIG_HIBERNATION */ diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 2d8e2b227db8..905d5bbd595f 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -38,7 +38,7 @@ #include "power.h" -#ifdef CONFIG_DEBUG_RODATA +#ifdef CONFIG_STRICT_KERNEL_RWX static bool hibernate_restore_protection; static bool hibernate_restore_protection_active; @@ -73,7 +73,7 @@ static inline void hibernate_restore_protection_begin(void) {} static inline void hibernate_restore_protection_end(void) {} static inline void hibernate_restore_protect_page(void *page_address) {} static inline void hibernate_restore_unprotect_page(void *page_address) {} -#endif /* CONFIG_DEBUG_RODATA */ +#endif /* CONFIG_STRICT_KERNEL_RWX */ static int swsusp_page_is_free(struct page *); static void swsusp_set_page_forbidden(struct page *); -- cgit v1.2.3