diff options
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm/kernel/elf.c | 79 | ||||
| -rw-r--r-- | arch/arm/kernel/module.c | 2 |
3 files changed, 81 insertions, 2 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 1d296fc8494..4305345987d 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -10,7 +10,7 @@ endif # Object file lists. -obj-y := compat.o entry-armv.o entry-common.o irq.o \ +obj-y := compat.o elf.o entry-armv.o entry-common.o irq.o \ process.o ptrace.o setup.o signal.o \ sys_arm.o stacktrace.o time.o traps.o diff --git a/arch/arm/kernel/elf.c b/arch/arm/kernel/elf.c new file mode 100644 index 00000000000..513f332f040 --- /dev/null +++ b/arch/arm/kernel/elf.c @@ -0,0 +1,79 @@ +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/personality.h> +#include <linux/binfmts.h> +#include <linux/elf.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) { + /* APCS26 is only allowed if the CPU supports it */ + if ((eflags & EF_ARM_APCS_26) && !(elf_hwcap & HWCAP_26BIT)) + return 0; + + /* VFP requires the supporting code */ + if ((eflags & 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 = PER_LINUX_32BIT; + + /* + * APCS-26 is only valid for OABI executables + */ + if ((eflags & EF_ARM_EABI_MASK) == EF_ARM_EABI_UNKNOWN) { + if (eflags & EF_ARM_APCS_26) + personality = PER_LINUX; + } + + 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(const struct elf32_hdr *x, int executable_stack) +{ + if (executable_stack != EXSTACK_ENABLE_X) + return 1; + if (cpu_architecture() <= CPU_ARCH_ARMv6) + return 1; + return 0; +} +EXPORT_SYMBOL(arm_elf_read_implies_exec); diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c index a68259a0ccc..9203ba7d58e 100644 --- a/arch/arm/kernel/module.c +++ b/arch/arm/kernel/module.c @@ -47,7 +47,7 @@ void *module_alloc(unsigned long size) if (!area) return NULL; - return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL); + return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC); } #else /* CONFIG_MMU */ void *module_alloc(unsigned long size) |