Commit 73d6eb48 authored by Ilya Leoshkevich's avatar Ilya Leoshkevich Committed by Heiko Carstens
Browse files

s390: enable HAVE_FUNCTION_ERROR_INJECTION 



This kernel feature is required for enabling BPF_KPROBE_OVERRIDE.

Define override_function_with_return() and regs_set_return_value()
functions, and fix compile errors in syscall_wrapper.h.

Signed-off-by: default avatarIlya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent 4631f3ca

arch/s390/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -145,6 +145,7 @@ config S390 
	select HAVE_EFFICIENT_UNALIGNED_ACCESS

	select HAVE_FENTRY

	select HAVE_FTRACE_MCOUNT_RECORD

	select HAVE_FUNCTION_ERROR_INJECTION

	select HAVE_FUNCTION_GRAPH_TRACER

	select HAVE_FUNCTION_TRACER

	select HAVE_FUTEX_CMPXCHG if FUTEX

arch/s390/include/asm/ptrace.h

+5 −0
Original line number Diff line number Diff line
@@ -184,5 +184,10 @@ static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) 
	return regs->gprs[15];

}



static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)

{

	regs->gprs[2] = rc;

}



#endif /* __ASSEMBLY__ */

#endif /* _S390_PTRACE_H */

arch/s390/include/asm/syscall_wrapper.h

+3 −3
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ 
})



#define __S390_SYS_STUBx(x, name, ...)					\

	asmlinkage long __s390_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))\

	asmlinkage long __s390_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__));\

	ALLOW_ERROR_INJECTION(__s390_sys##name, ERRNO);			\

	asmlinkage long __s390_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))\

	{								\
@@ -46,7 +46,7 @@ 
#define COMPAT_SYSCALL_DEFINE0(sname)					\

	SYSCALL_METADATA(_##sname, 0);					\

	asmlinkage long __s390_compat_sys_##sname(void);		\

	ALLOW_ERROR_INJECTION(__s390_compat__sys_##sname, ERRNO);	\

	ALLOW_ERROR_INJECTION(__s390_compat_sys_##sname, ERRNO);	\

	asmlinkage long __s390_compat_sys_##sname(void)



#define SYSCALL_DEFINE0(sname)						\
@@ -72,7 +72,7 @@ 
	asmlinkage long __s390_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\

	asmlinkage long __s390_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))	\

		__attribute__((alias(__stringify(__se_compat_sys##name))));	\

	ALLOW_ERROR_INJECTION(compat_sys##name, ERRNO);				\

	ALLOW_ERROR_INJECTION(__s390_compat_sys##name, ERRNO);			\

	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\

	asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__));	\

	asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))	\

arch/s390/lib/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -14,3 +14,5 @@ KASAN_SANITIZE_uaccess.o := n 


obj-$(CONFIG_S390_UNWIND_SELFTEST) += test_unwind.o

CFLAGS_test_unwind.o += -fno-optimize-sibling-calls



lib-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o

arch/s390/lib/error-inject.c

0 → 100644
+14 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+

#include <asm/ptrace.h>

#include <linux/error-injection.h>

#include <linux/kprobes.h>



void override_function_with_return(struct pt_regs *regs)

{

	/*

	 * Emulate 'br 14'. 'regs' is captured by kprobes on entry to some

	 * kernel function.

	 */

	regs->psw.addr = regs->gprs[14];

}

NOKPROBE_SYMBOL(override_function_with_return);