115 lines
2.9 KiB
C
115 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/export.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/personality.h>
|
|
#include <linux/binfmts.h>
|
|
#include <linux/elf.h>
|
|
#include <linux/elf-fdpic.h>
|
|
#include <asm/system_info.h>
|
|
|
|
int elf_check_arch(const struct elf32_hdr *x)
|
|
{
|
|
unsigned int eflags;
|
|
|
|
/* Make sure it's an ARM executable */
|
|
if (x->e_machine != EM_ARM)
|
|
return 0;
|
|
|
|
/* Make sure the entry address is reasonable */
|
|
if (x->e_entry & 1) {
|
|
if (!(elf_hwcap & HWCAP_THUMB))
|
|
return 0;
|
|
} else if (x->e_entry & 3)
|
|
return 0;
|
|
|
|
eflags = x->e_flags;
|
|
if ((eflags & EF_ARM_EABI_MASK) == EF_ARM_EABI_UNKNOWN) {
|
|
unsigned int flt_fmt;
|
|
|
|
/* APCS26 is only allowed if the CPU supports it */
|
|
if ((eflags & EF_ARM_APCS_26) && !(elf_hwcap & HWCAP_26BIT))
|
|
return 0;
|
|
|
|
flt_fmt = eflags & (EF_ARM_VFP_FLOAT | EF_ARM_SOFT_FLOAT);
|
|
|
|
/* VFP requires the supporting code */
|
|
if (flt_fmt == EF_ARM_VFP_FLOAT && !(elf_hwcap & HWCAP_VFP))
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL(elf_check_arch);
|
|
|
|
void elf_set_personality(const struct elf32_hdr *x)
|
|
{
|
|
unsigned int eflags = x->e_flags;
|
|
unsigned int personality = current->personality & ~PER_MASK;
|
|
|
|
/*
|
|
* We only support Linux ELF executables, so always set the
|
|
* personality to LINUX.
|
|
*/
|
|
personality |= PER_LINUX;
|
|
|
|
/*
|
|
* APCS-26 is only valid for OABI executables
|
|
*/
|
|
if ((eflags & EF_ARM_EABI_MASK) == EF_ARM_EABI_UNKNOWN &&
|
|
(eflags & EF_ARM_APCS_26))
|
|
personality &= ~ADDR_LIMIT_32BIT;
|
|
else
|
|
personality |= ADDR_LIMIT_32BIT;
|
|
|
|
set_personality(personality);
|
|
|
|
/*
|
|
* Since the FPA coprocessor uses CP1 and CP2, and iWMMXt uses CP0
|
|
* and CP1, we only enable access to the iWMMXt coprocessor if the
|
|
* binary is EABI or softfloat (and thus, guaranteed not to use
|
|
* FPA instructions.)
|
|
*/
|
|
if (elf_hwcap & HWCAP_IWMMXT &&
|
|
eflags & (EF_ARM_EABI_MASK | EF_ARM_SOFT_FLOAT)) {
|
|
set_thread_flag(TIF_USING_IWMMXT);
|
|
} else {
|
|
clear_thread_flag(TIF_USING_IWMMXT);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(elf_set_personality);
|
|
|
|
/*
|
|
* Set READ_IMPLIES_EXEC if:
|
|
* - the binary requires an executable stack
|
|
* - we're running on a CPU which doesn't support NX.
|
|
*/
|
|
int arm_elf_read_implies_exec(int executable_stack)
|
|
{
|
|
if (executable_stack != EXSTACK_DISABLE_X)
|
|
return 1;
|
|
if (cpu_architecture() < CPU_ARCH_ARMv6)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(arm_elf_read_implies_exec);
|
|
|
|
#if defined(CONFIG_MMU) && defined(CONFIG_BINFMT_ELF_FDPIC)
|
|
|
|
void elf_fdpic_arch_lay_out_mm(struct elf_fdpic_params *exec_params,
|
|
struct elf_fdpic_params *interp_params,
|
|
unsigned long *start_stack,
|
|
unsigned long *start_brk)
|
|
{
|
|
elf_set_personality(&exec_params->hdr);
|
|
|
|
exec_params->load_addr = 0x8000;
|
|
interp_params->load_addr = ELF_ET_DYN_BASE;
|
|
*start_stack = TASK_SIZE - SZ_16M;
|
|
|
|
if ((exec_params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) == ELF_FDPIC_FLAG_INDEPENDENT) {
|
|
exec_params->flags &= ~ELF_FDPIC_FLAG_ARRANGEMENT;
|
|
exec_params->flags |= ELF_FDPIC_FLAG_CONSTDISP;
|
|
}
|
|
}
|
|
|
|
#endif
|