ARM: 7577/1: arch/add syscall_get_arch

Provide an ARM implementation of syscall_get_arch. This is a pre-requisite
for CONFIG_HAVE_ARCH_SECCOMP_FILTER.

Signed-off-by: Will Drewry <[e-mail]>
Signed-off-by: Kees Cook <[e-mail]>
Reviewed-by: Will Deacon <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/include/asm/syscall.h

···
 #ifndef _ASM_ARM_SYSCALL_H
 #define _ASM_ARM_SYSCALL_H
 
+#include <linux/audit.h> /* for AUDIT_ARCH_* */
+#include <linux/elf.h> /* for ELF_EM */
 #include <linux/err.h>
 #include <linux/sched.h>
 
···
 	}
 
 	memcpy(&regs->ARM_r0 + i, args, n * sizeof(args[0]));
+}
+
+static inline int syscall_get_arch(struct task_struct *task,
+				   struct pt_regs *regs)
+{
+	/* ARM tasks don't change audit architectures on the fly. */
+	return AUDIT_ARCH_ARM;
 }
 
 #endif /* _ASM_ARM_SYSCALL_H */