From 753c4dd6a2fa2af81f5d809d610d29f2d9dd9bc1 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 10 Oct 2008 21:33:20 +0200 Subject: [PATCH] [S390] ptrace changes * System call parameter and result access functions * Add tracehook calls * Split syscall_trace into two functions do_syscall_trace_enter and do_syscall_trace_exit Signed-off-by: Martin Schwidefsky --- arch/s390/Kconfig | 1 + arch/s390/include/asm/ptrace.h | 1 + arch/s390/include/asm/syscall.h | 80 +++++++++++++++++++++++++++++++++++++ arch/s390/include/asm/thread_info.h | 2 + arch/s390/kernel/entry.S | 50 ++++++++++++++++++----- arch/s390/kernel/entry64.S | 42 ++++++++++++++----- arch/s390/kernel/ptrace.c | 61 +++++++++++++++------------- arch/s390/kernel/signal.c | 13 ++++++ 8 files changed, 202 insertions(+), 48 deletions(-) create mode 100644 arch/s390/include/asm/syscall.h diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 8d41908..4c03049 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -74,6 +74,7 @@ config S390 select HAVE_KPROBES select HAVE_KRETPROBES select HAVE_KVM if 64BIT + select HAVE_ARCH_TRACEHOOK source "init/Kconfig" diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h index af2c9ac..a7226f8 100644 --- a/arch/s390/include/asm/ptrace.h +++ b/arch/s390/include/asm/ptrace.h @@ -490,6 +490,7 @@ extern void user_disable_single_step(struct task_struct *); #define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0) #define instruction_pointer(regs) ((regs)->psw.addr & PSW_ADDR_INSN) +#define user_stack_pointer(regs)((regs)->gprs[15]) #define regs_return_value(regs)((regs)->gprs[2]) #define profile_pc(regs) instruction_pointer(regs) extern void show_regs(struct pt_regs * regs); diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h new file mode 100644 index 0000000..6e62397 --- /dev/null +++ b/arch/s390/include/asm/syscall.h @@ -0,0 +1,80 @@ +/* + * Access to user system call parameters and results + * + * Copyright IBM Corp. 2008 + * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2 only) + * as published by the Free Software Foundation. + */ + +#ifndef _ASM_SYSCALL_H +#define _ASM_SYSCALL_H 1 + +#include + +static inline long syscall_get_nr(struct task_struct *task, + struct pt_regs *regs) +{ + if (regs->trap != __LC_SVC_OLD_PSW) + return -1; + return regs->gprs[2]; +} + +static inline void syscall_rollback(struct task_struct *task, + struct pt_regs *regs) +{ + regs->gprs[2] = regs->orig_gpr2; +} + +static inline long syscall_get_error(struct task_struct *task, + struct pt_regs *regs) +{ + return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0; +} + +static inline long syscall_get_return_value(struct task_struct *task, + struct pt_regs *regs) +{ + return regs->gprs[2]; +} + +static inline void syscall_set_return_value(struct task_struct *task, + struct pt_regs *regs, + int error, long val) +{ + regs->gprs[2] = error ? -error : val; +} + +static inline void syscall_get_arguments(struct task_struct *task, + struct pt_regs *regs, + unsigned int i, unsigned int n, + unsigned long *args) +{ + BUG_ON(i + n > 6); +#ifdef CONFIG_COMPAT + if (test_tsk_thread_flag(task, TIF_31BIT)) { + if (i + n == 6) + args[--n] = (u32) regs->args[0]; + while (n-- > 0) + args[n] = (u32) regs->gprs[2 + i + n]; + } +#endif + if (i + n == 6) + args[--n] = regs->args[0]; + memcpy(args, ®s->gprs[2 + i], n * sizeof(args[0])); +} + +static inline void syscall_set_arguments(struct task_struct *task, + struct pt_regs *regs, + unsigned int i, unsigned int n, + const unsigned long *args) +{ + BUG_ON(i + n > 6); + if (i + n == 6) + regs->args[0] = args[--n]; + memcpy(®s->gprs[2 + i], args, n * sizeof(args[0])); +} + +#endif /* _ASM_SYSCALL_H */ diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h index 91a8f93..ea40a9d 100644 --- a/arch/s390/include/asm/thread_info.h +++ b/arch/s390/include/asm/thread_info.h @@ -86,6 +86,7 @@ static inline struct thread_info *current_thread_info(void) * thread information flags bit numbers */ #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ +#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ #define TIF_SIGPENDING 2 /* signal pending */ #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ #define TIF_RESTART_SVC 4 /* restart svc with new svc number */ @@ -100,6 +101,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_RESTORE_SIGMASK 20 /* restore signal mask in do_signal() */ #define _TIF_SYSCALL_TRACE (1< #include #include +#include #include #include @@ -639,40 +640,44 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, } #endif -asmlinkage void -syscall_trace(struct pt_regs *regs, int entryexit) +asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) { - if (unlikely(current->audit_context) && entryexit) - audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]); - - if (!test_thread_flag(TIF_SYSCALL_TRACE)) - goto out; - if (!(current->ptrace & PT_PTRACED)) - goto out; - ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) - ? 0x80 : 0)); + long ret; /* - * If the debuffer has set an invalid system call number, - * we prepare to skip the system call restart handling. + * The sysc_tracesys code in entry.S stored the system + * call number to gprs[2]. */ - if (!entryexit && regs->gprs[2] >= NR_syscalls) + ret = regs->gprs[2]; + if (test_thread_flag(TIF_SYSCALL_TRACE) && + (tracehook_report_syscall_entry(regs) || + regs->gprs[2] >= NR_syscalls)) { + /* + * Tracing decided this syscall should not happen or the + * debugger stored an invalid system call number. Skip + * the system call and the system call restart handling. + */ regs->trap = -1; - - /* - * this isn't the same as continuing with a signal, but it will do - * for normal use. strace only continues with a signal if the - * stopping signal is not SIGTRAP. -brl - */ - if (current->exit_code) { - send_sig(current->exit_code, current, 1); - current->exit_code = 0; + ret = -1; } - out: - if (unlikely(current->audit_context) && !entryexit) - audit_syscall_entry(test_thread_flag(TIF_31BIT)?AUDIT_ARCH_S390:AUDIT_ARCH_S390X, - regs->gprs[2], regs->orig_gpr2, regs->gprs[3], - regs->gprs[4], regs->gprs[5]); + + if (unlikely(current->audit_context)) + audit_syscall_entry(test_thread_flag(TIF_31BIT) ? + AUDIT_ARCH_S390 : AUDIT_ARCH_S390X, + regs->gprs[2], regs->orig_gpr2, + regs->gprs[3], regs->gprs[4], + regs->gprs[5]); + return ret; +} + +asmlinkage void do_syscall_trace_exit(struct pt_regs *regs) +{ + if (unlikely(current->audit_context)) + audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), + regs->gprs[2]); + + if (test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall_exit(regs, 0); } /* diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c index b976820..4f7fc30 100644 --- a/arch/s390/kernel/signal.c +++ b/arch/s390/kernel/signal.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -507,6 +508,12 @@ void do_signal(struct pt_regs *regs) */ if (current->thread.per_info.single_step) set_thread_flag(TIF_SINGLE_STEP); + + /* + * Let tracing know that we've done the handler setup. + */ + tracehook_signal_handler(signr, &info, &ka, regs, + test_thread_flag(TIF_SINGLE_STEP)); } return; } @@ -526,3 +533,9 @@ void do_signal(struct pt_regs *regs) set_thread_flag(TIF_RESTART_SVC); } } + +void do_notify_resume(struct pt_regs *regs) +{ + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); +} -- 2.7.4