[PATCH 2/2] arm64: use the correct function type in SYSCALL_DEFINE0

From: Sami Tolvanen
Date: Wed May 01 2019 - 16:05:25 EST


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@xxxxxxxxxx>
---
arch/arm64/include/asm/syscall_wrapper.h | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/include/asm/syscall_wrapper.h b/arch/arm64/include/asm/syscall_wrapper.h
index a4477e515b798..507d0ee6bc690 100644
--- 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
--
2.21.0.593.g511ec345e18-goog