[PATCH 5.4 047/203] syscalls/x86: Wire up COMPAT_SYSCALL_DEFINE0

Greg Kroah-Hartman
2020-01-16T23:46:28Z

From: Andy Lutomirski <luto@kernel.org>

commit cf3b83e19d7c928e05a5d193c375463182c6029a upstream.

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@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H . Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191008224049.115427-3-samitolvanen@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/x86/include/asm/syscall_wrapper.h | 32 ++++++++++++++++++++++++++++++--
1 file changed, 30 insertions(+), 2 deletions(-)

--- 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__));\