[RESEND PATCH v2 2/5] x86/syscalls: Wire up COMPAT_SYSCALL_DEFINE0

From: Sami Tolvanen
Date: Tue Oct 08 2019 - 18:41:10 EST


From: Andy Lutomirski <luto@xxxxxxxxxx>

x86 has special handling for COMPAT_SYSCALL_DEFINEx, but there was
no override for COMPAT_SYSCALL_DEFINE0. Wire it up so that we can
use it for rt_sigreturn.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
---
arch/x86/include/asm/syscall_wrapper.h | 32 ++++++++++++++++++++++++--
1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/syscall_wrapper.h b/arch/x86/include/asm/syscall_wrapper.h
index 90eb70df0b18..3dab04841494 100644
--- a/arch/x86/include/asm/syscall_wrapper.h
+++ b/arch/x86/include/asm/syscall_wrapper.h
@@ -28,13 +28,21 @@
* kernel/sys_ni.c and SYS_NI in kernel/time/posix-stubs.c to cover this
* case as well.
*/
+#define __IA32_COMPAT_SYS_STUB0(x, name) \
+ asmlinkage long __ia32_compat_sys_##name(const struct pt_regs *regs);\
+ ALLOW_ERROR_INJECTION(__ia32_compat_sys_##name, ERRNO); \
+ asmlinkage long __ia32_compat_sys_##name(const struct pt_regs *regs)\
+ { \
+ return __se_compat_sys_##name(); \
+ }
+
#define __IA32_COMPAT_SYS_STUBx(x, name, ...) \
asmlinkage long __ia32_compat_sys##name(const struct pt_regs *regs);\
ALLOW_ERROR_INJECTION(__ia32_compat_sys##name, ERRNO); \
asmlinkage long __ia32_compat_sys##name(const struct pt_regs *regs)\
{ \
return __se_compat_sys##name(SC_IA32_REGS_TO_ARGS(x,__VA_ARGS__));\
- } \
+ }

#define __IA32_SYS_STUBx(x, name, ...) \
asmlinkage long __ia32_sys##name(const struct pt_regs *regs); \
@@ -76,15 +84,24 @@
* of the x86-64-style parameter ordering of x32 syscalls. The syscalls common
* with x86_64 obviously do not need such care.
*/
+#define __X32_COMPAT_SYS_STUB0(x, name, ...) \
+ asmlinkage long __x32_compat_sys_##name(const struct pt_regs *regs);\
+ ALLOW_ERROR_INJECTION(__x32_compat_sys_##name, ERRNO); \
+ asmlinkage long __x32_compat_sys_##name(const struct pt_regs *regs)\
+ { \
+ return __se_compat_sys_##name();\
+ }
+
#define __X32_COMPAT_SYS_STUBx(x, name, ...) \
asmlinkage long __x32_compat_sys##name(const struct pt_regs *regs);\
ALLOW_ERROR_INJECTION(__x32_compat_sys##name, ERRNO); \
asmlinkage long __x32_compat_sys##name(const struct pt_regs *regs)\
{ \
return __se_compat_sys##name(SC_X86_64_REGS_TO_ARGS(x,__VA_ARGS__));\
- } \
+ }

#else /* CONFIG_X86_X32 */
+#define __X32_COMPAT_SYS_STUB0(x, name)
#define __X32_COMPAT_SYS_STUBx(x, name, ...)
#endif /* CONFIG_X86_X32 */

@@ -95,6 +112,17 @@
* mapping of registers to parameters, we need to generate stubs for each
* of them.
*/
+#define COMPAT_SYSCALL_DEFINE0(name) \
+ static long __se_compat_sys_##name(void); \
+ static inline long __do_compat_sys_##name(void); \
+ __IA32_COMPAT_SYS_STUB0(x, name) \
+ __X32_COMPAT_SYS_STUB0(x, name) \
+ static long __se_compat_sys_##name(void) \
+ { \
+ return __do_compat_sys_##name(); \
+ } \
+ static inline long __do_compat_sys_##name(void)
+
#define COMPAT_SYSCALL_DEFINEx(x, name, ...) \
static long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
--
2.23.0.581.g78d2f28ef7-goog