From 73d6eb48d26930f0cbdc8bf1ccb0ad964e7d2b90 Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Wed, 22 Jul 2020 23:58:54 +0200 Subject: 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: Ilya Leoshkevich Signed-off-by: Heiko Carstens --- arch/s390/Kconfig | 1 + arch/s390/include/asm/ptrace.h | 5 +++++ arch/s390/include/asm/syscall_wrapper.h | 6 +++--- arch/s390/lib/Makefile | 2 ++ arch/s390/lib/error-inject.c | 14 ++++++++++++++ 5 files changed, 25 insertions(+), 3 deletions(-) create mode 100644 arch/s390/lib/error-inject.c (limited to 'arch/s390') diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index d95d323cf213..9cfd8de907cb 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -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 diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h index f009a13afe71..16b3e4396312 100644 --- a/arch/s390/include/asm/ptrace.h +++ b/arch/s390/include/asm/ptrace.h @@ -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 */ diff --git a/arch/s390/include/asm/syscall_wrapper.h b/arch/s390/include/asm/syscall_wrapper.h index 3c3d6fe8e2f0..1320f4213d80 100644 --- a/arch/s390/include/asm/syscall_wrapper.h +++ b/arch/s390/include/asm/syscall_wrapper.h @@ -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__)) \ diff --git a/arch/s390/lib/Makefile b/arch/s390/lib/Makefile index 28fd66d558ff..678333936f78 100644 --- a/arch/s390/lib/Makefile +++ b/arch/s390/lib/Makefile @@ -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 diff --git a/arch/s390/lib/error-inject.c b/arch/s390/lib/error-inject.c new file mode 100644 index 000000000000..8c9d4da87eef --- /dev/null +++ b/arch/s390/lib/error-inject.c @@ -0,0 +1,14 @@ +// SPDX-License-Identifier: GPL-2.0+ +#include +#include +#include + +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); -- cgit v1.2.3