[PATCH v3 10/10] mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE
From: Kees Cook <hidden>
Date: 2015-03-04 02:10:25
Also in:
linux-fsdevel, linux-mips, linuxppc-dev, lkml
Subsystem:
arm port, arm64 port (aarch64 architecture), exec & binfmt api, elf, filesystems (vfs and infrastructure), linux for powerpc (32-bit and 64-bit), mips, s390 architecture, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Russell King, Catalin Marinas, Will Deacon, Kees Cook, Alexander Viro, Christian Brauner, Madhavan Srinivasan, Michael Ellerman, Thomas Bogendoerfer, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
The arch_randomize_brk() function is used on several architectures, even those that don't support ET_DYN ASLR. To avoid bulky extern/#define tricks, consolidate the support under CONFIG_ARCH_HAS_ELF_RANDOMIZE for the architectures that support it, while still handling CONFIG_COMPAT_BRK. Signed-off-by: Kees Cook <redacted> --- arch/Kconfig | 1 + arch/arm/include/asm/elf.h | 4 ---- arch/arm64/include/asm/elf.h | 4 ---- arch/mips/include/asm/elf.h | 4 ---- arch/powerpc/include/asm/elf.h | 4 ---- arch/s390/include/asm/elf.h | 3 --- arch/x86/include/asm/elf.h | 3 --- fs/binfmt_elf.c | 4 +--- include/linux/elf-randomize.h | 12 ++++++++++++ 9 files changed, 14 insertions(+), 25 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 9ff5aa8fa2c1..d4f270a54fe6 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig@@ -490,6 +490,7 @@ config ARCH_HAS_ELF_RANDOMIZE An architecture supports choosing randomized locations for stack, mmap, brk, and ET_DYN. Defined functions: - arch_mmap_rnd() + - arch_randomize_brk() # # ABI hall of shame
diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h
index afb9cafd3786..c1ff8ab12914 100644
--- a/arch/arm/include/asm/elf.h
+++ b/arch/arm/include/asm/elf.h@@ -125,10 +125,6 @@ int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs); extern void elf_set_personality(const struct elf32_hdr *); #define SET_PERSONALITY(ex) elf_set_personality(&(ex)) -struct mm_struct; -extern unsigned long arch_randomize_brk(struct mm_struct *mm); -#define arch_randomize_brk arch_randomize_brk - #ifdef CONFIG_MMU #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 struct linux_binprm;
diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index f724db00b235..faad6df49e5b 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h@@ -156,10 +156,6 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm, #define STACK_RND_MASK (0x3ffff >> (PAGE_SHIFT - 12)) #endif -struct mm_struct; -extern unsigned long arch_randomize_brk(struct mm_struct *mm); -#define arch_randomize_brk arch_randomize_brk - #ifdef CONFIG_COMPAT #ifdef __AARCH64EB__
diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h
index 535f196ffe02..31d747d46a23 100644
--- a/arch/mips/include/asm/elf.h
+++ b/arch/mips/include/asm/elf.h@@ -410,10 +410,6 @@ struct linux_binprm; extern int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp); -struct mm_struct; -extern unsigned long arch_randomize_brk(struct mm_struct *mm); -#define arch_randomize_brk arch_randomize_brk - struct arch_elf_state { int fp_abi; int interp_fp_abi;
diff --git a/arch/powerpc/include/asm/elf.h b/arch/powerpc/include/asm/elf.h
index 57d289acb803..ee46ffef608e 100644
--- a/arch/powerpc/include/asm/elf.h
+++ b/arch/powerpc/include/asm/elf.h@@ -128,10 +128,6 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm, (0x7ff >> (PAGE_SHIFT - 12)) : \ (0x3ffff >> (PAGE_SHIFT - 12))) -extern unsigned long arch_randomize_brk(struct mm_struct *mm); -#define arch_randomize_brk arch_randomize_brk - - #ifdef CONFIG_SPU_BASE /* Notes used in ET_CORE. Note name is "SPU/<fd>/<filename>". */ #define NT_SPU 1
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index d0db9d944b6d..fdda72e56404 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h@@ -226,9 +226,6 @@ struct linux_binprm; #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 int arch_setup_additional_pages(struct linux_binprm *, int); -extern unsigned long arch_randomize_brk(struct mm_struct *mm); -#define arch_randomize_brk arch_randomize_brk - void *fill_cpu_elf_notes(void *ptr, struct save_area *sa, __vector128 *vxrs); #endif
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index ca3347a9dab5..bbdace22daf8 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h@@ -338,9 +338,6 @@ extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp); #define compat_arch_setup_additional_pages compat_arch_setup_additional_pages -extern unsigned long arch_randomize_brk(struct mm_struct *mm); -#define arch_randomize_brk arch_randomize_brk - /* * True on X86_32 or when emulating IA32 on X86_64 */
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 6f08f5fa99dc..a115da230ce0 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c@@ -1043,15 +1043,13 @@ static int load_elf_binary(struct linux_binprm *bprm) current->mm->end_data = end_data; current->mm->start_stack = bprm->p; -#ifdef arch_randomize_brk if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) { current->mm->brk = current->mm->start_brk = arch_randomize_brk(current->mm); -#ifdef CONFIG_COMPAT_BRK +#ifdef compat_brk_randomized current->brk_randomized = 1; #endif } -#endif if (current->personality & MMAP_PAGE_ZERO) { /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
diff --git a/include/linux/elf-randomize.h b/include/linux/elf-randomize.h
index 7a4eda02d2b1..b5f0bda9472e 100644
--- a/include/linux/elf-randomize.h
+++ b/include/linux/elf-randomize.h@@ -1,10 +1,22 @@ #ifndef _ELF_RANDOMIZE_H #define _ELF_RANDOMIZE_H +struct mm_struct; + #ifndef CONFIG_ARCH_HAS_ELF_RANDOMIZE static inline unsigned long arch_mmap_rnd(void) { return 0; } +# if defined(arch_randomize_brk) && defined(CONFIG_COMPAT_BRK) +# define compat_brk_randomized +# endif +# ifndef arch_randomize_brk +# define arch_randomize_brk(mm) (mm->brk) +# endif #else extern unsigned long arch_mmap_rnd(void); +extern unsigned long arch_randomize_brk(struct mm_struct *mm); +# ifdef CONFIG_COMPAT_BRK +# define compat_brk_randomized +# endif #endif #endif
--
1.9.1