arm64: use the correct function type in SYSCALL_DEFINE0

Although a syscall defined using SYSCALL_DEFINE0 doesn't accept
parameters, use the correct function type to avoid indirect call
type mismatches with Control-Flow Integrity checking.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/include/asm/syscall_wrapper.h b/arch/arm64/include/asm/syscall_wrapper.h
index a4477e515b798d3788c210ac184f9284e059e989..507d0ee6bc690093f84371089413eccf4560a101 100644 (file)
--- a/arch/arm64/include/asm/syscall_wrapper.h
+++ b/arch/arm64/include/asm/syscall_wrapper.h
@@ -30,10 +30,10 @@
        }                                                                               \
        static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
-#define COMPAT_SYSCALL_DEFINE0(sname)                                  \
-       asmlinkage long __arm64_compat_sys_##sname(void);               \
-       ALLOW_ERROR_INJECTION(__arm64_compat_sys_##sname, ERRNO);       \
-       asmlinkage long __arm64_compat_sys_##sname(void)
+#define COMPAT_SYSCALL_DEFINE0(sname)                                                  \
+       asmlinkage long __arm64_compat_sys_##sname(const struct pt_regs *__unused);     \
+       ALLOW_ERROR_INJECTION(__arm64_compat_sys_##sname, ERRNO);                       \
+       asmlinkage long __arm64_compat_sys_##sname(const struct pt_regs *__unused)
 
 #define COND_SYSCALL_COMPAT(name) \
        cond_syscall(__arm64_compat_sys_##name);
@@ -62,11 +62,11 @@
        static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
 #ifndef SYSCALL_DEFINE0
-#define SYSCALL_DEFINE0(sname)                                 \
-       SYSCALL_METADATA(_##sname, 0);                          \
-       asmlinkage long __arm64_sys_##sname(void);              \
-       ALLOW_ERROR_INJECTION(__arm64_sys_##sname, ERRNO);      \
-       asmlinkage long __arm64_sys_##sname(void)
+#define SYSCALL_DEFINE0(sname)                                                 \
+       SYSCALL_METADATA(_##sname, 0);                                          \
+       asmlinkage long __arm64_sys_##sname(const struct pt_regs *__unused);    \
+       ALLOW_ERROR_INJECTION(__arm64_sys_##sname, ERRNO);                      \
+       asmlinkage long __arm64_sys_##sname(const struct pt_regs *__unused)
 #endif
 
 #ifndef COND_SYSCALL