[PATCH v3 seccomp 1/5] x86: Enable seccomp architecture tracking

[YiFei Zhu]

From: Kees Cook <keescook@xxxxxxxxxxxx>

Provide seccomp internals with the details to calculate which syscall
table the running kernel is expecting to deal with. This allows for
efficient architecture pinning and paves the way for constant-action
bitmaps.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
[YiFei: Removed x32, added macro for nr_syscalls]
Signed-off-by: YiFei Zhu <yifeifz2@xxxxxxxxxxxx>
---
 arch/x86/include/asm/seccomp.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/x86/include/asm/seccomp.h b/arch/x86/include/asm/seccomp.h
index 2bd1338de236..7b3a58271656 100644
--- a/arch/x86/include/asm/seccomp.h
+++ b/arch/x86/include/asm/seccomp.h
@@ -16,6 +16,18 @@
 #define __NR_seccomp_sigreturn_32	__NR_ia32_sigreturn
 #endif
 
+#ifdef CONFIG_X86_64
+# define SECCOMP_ARCH_DEFAULT			AUDIT_ARCH_X86_64
+# define SECCOMP_ARCH_DEFAULT_NR		NR_syscalls
+# ifdef CONFIG_COMPAT
+#  define SECCOMP_ARCH_COMPAT			AUDIT_ARCH_I386
+#  define SECCOMP_ARCH_COMPAT_NR		IA32_NR_syscalls
+# endif
+#else /* !CONFIG_X86_64 */
+# define SECCOMP_ARCH_DEFAULT		AUDIT_ARCH_I386
+# define SECCOMP_ARCH_DEFAULT_NR	NR_syscalls
+#endif
+
 #include <asm-generic/seccomp.h>
 
 #endif /* _ASM_X86_SECCOMP_H */
-- 
2.28.0