linux_dsm_epyc7002/arch/arm/include/asm/processor.h
Alexandre Ghiti dba79c3df4 arm: use generic mmap top-down layout and brk randomization
arm uses a top-down mmap layout by default that exactly fits the generic
functions, so get rid of arch specific code and use the generic version by
selecting ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT.

As ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT selects ARCH_HAS_ELF_RANDOMIZE,
use the generic version of arch_randomize_brk since it also fits.  Note
that this commit also removes the possibility for arm to have elf
randomization and no MMU: without MMU, the security added by randomization
is worth nothing.

Note that it is safe to remove STACK_RND_MASK since it matches the default
value.

Link: http://lkml.kernel.org/r/20190730055113.23635-9-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:12 -07:00

146 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/include/asm/processor.h
*
* Copyright (C) 1995-1999 Russell King
*/
#ifndef __ASM_ARM_PROCESSOR_H
#define __ASM_ARM_PROCESSOR_H
#ifdef __KERNEL__
#include <asm/hw_breakpoint.h>
#include <asm/ptrace.h>
#include <asm/types.h>
#include <asm/unified.h>
#ifdef __KERNEL__
#define STACK_TOP ((current->personality & ADDR_LIMIT_32BIT) ? \
TASK_SIZE : TASK_SIZE_26)
#define STACK_TOP_MAX TASK_SIZE
#endif
struct debug_info {
#ifdef CONFIG_HAVE_HW_BREAKPOINT
struct perf_event *hbp[ARM_MAX_HBP_SLOTS];
#endif
};
struct thread_struct {
/* fault info */
unsigned long address;
unsigned long trap_no;
unsigned long error_code;
/* debugging */
struct debug_info debug;
};
/*
* Everything usercopied to/from thread_struct is statically-sized, so
* no hardened usercopy whitelist is needed.
*/
static inline void arch_thread_struct_whitelist(unsigned long *offset,
unsigned long *size)
{
*offset = *size = 0;
}
#define INIT_THREAD { }
#define start_thread(regs,pc,sp) \
({ \
unsigned long r7, r8, r9; \
\
if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC)) { \
r7 = regs->ARM_r7; \
r8 = regs->ARM_r8; \
r9 = regs->ARM_r9; \
} \
memset(regs->uregs, 0, sizeof(regs->uregs)); \
if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) && \
current->personality & FDPIC_FUNCPTRS) { \
regs->ARM_r7 = r7; \
regs->ARM_r8 = r8; \
regs->ARM_r9 = r9; \
regs->ARM_r10 = current->mm->start_data; \
} else if (!IS_ENABLED(CONFIG_MMU)) \
regs->ARM_r10 = current->mm->start_data; \
if (current->personality & ADDR_LIMIT_32BIT) \
regs->ARM_cpsr = USR_MODE; \
else \
regs->ARM_cpsr = USR26_MODE; \
if (elf_hwcap & HWCAP_THUMB && pc & 1) \
regs->ARM_cpsr |= PSR_T_BIT; \
regs->ARM_cpsr |= PSR_ENDSTATE; \
regs->ARM_pc = pc & ~1; /* pc */ \
regs->ARM_sp = sp; /* sp */ \
})
/* Forward declaration, a strange C thing */
struct task_struct;
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
unsigned long get_wchan(struct task_struct *p);
#if __LINUX_ARM_ARCH__ == 6 || defined(CONFIG_ARM_ERRATA_754327)
#define cpu_relax() \
do { \
smp_mb(); \
__asm__ __volatile__("nop; nop; nop; nop; nop; nop; nop; nop; nop; nop;"); \
} while (0)
#else
#define cpu_relax() barrier()
#endif
#define task_pt_regs(p) \
((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
#define KSTK_EIP(tsk) task_pt_regs(tsk)->ARM_pc
#define KSTK_ESP(tsk) task_pt_regs(tsk)->ARM_sp
#ifdef CONFIG_SMP
#define __ALT_SMP_ASM(smp, up) \
"9998: " smp "\n" \
" .pushsection \".alt.smp.init\", \"a\"\n" \
" .long 9998b\n" \
" " up "\n" \
" .popsection\n"
#else
#define __ALT_SMP_ASM(smp, up) up
#endif
/*
* Prefetching support - only ARMv5.
*/
#if __LINUX_ARM_ARCH__ >= 5
#define ARCH_HAS_PREFETCH
static inline void prefetch(const void *ptr)
{
__asm__ __volatile__(
"pld\t%a0"
:: "p" (ptr));
}
#if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
#define ARCH_HAS_PREFETCHW
static inline void prefetchw(const void *ptr)
{
__asm__ __volatile__(
".arch_extension mp\n"
__ALT_SMP_ASM(
"pldw\t%a0",
"pld\t%a0"
)
:: "p" (ptr));
}
#endif
#endif
#endif
#endif /* __ASM_ARM_PROCESSOR_H */