[tip: x86/entry] syscalls/x86: Wire up COMPAT_SYSCALL_DEFINE0

From: tip-bot2 for Andy Lutomirski
Date: Fri Oct 11 2019 - 07:22:15 EST


The following commit has been merged into the x86/entry branch of tip:

Commit-ID: cf3b83e19d7c928e05a5d193c375463182c6029a
Gitweb: https://git.kernel.org/tip/cf3b83e19d7c928e05a5d193c375463182c6029a
Author: Andy Lutomirski <luto@xxxxxxxxxx>
AuthorDate: Tue, 08 Oct 2019 15:40:46 -07:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Fri, 11 Oct 2019 12:49:18 +02:00

syscalls/x86: Wire up COMPAT_SYSCALL_DEFINE0

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>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: H . Peter Anvin <hpa@xxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20191008224049.115427-3-samitolvanen@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@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 90eb70d..3dab048 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__));\