[PATCH] csky: Update syscall_trace_enter/exit implementation
From: guoren
Date: Mon Mar 25 2019 - 08:04:05 EST
From: Guo Ren <ren_guo@xxxxxxxxx>
Previous syscall_trace implementation couldn't support AUDITSYSCALL and
SYSCALL_TRACEPOINTS. Now we redesign it to support audit_syscall
and syscall_tracepoints just like other archs'.
Signed-off-by: Guo Ren <ren_guo@xxxxxxxxx>
Cc: Dmitry V. Levin <ldv@xxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/csky/Kconfig | 2 ++
arch/csky/include/asm/syscall.h | 2 ++
arch/csky/include/asm/thread_info.h | 25 ++++++++-----------
arch/csky/include/asm/unistd.h | 2 ++
arch/csky/include/uapi/asm/ptrace.h | 5 ++++
arch/csky/kernel/entry.S | 21 +++++++---------
arch/csky/kernel/ptrace.c | 50 +++++++++++++++++--------------------
7 files changed, 54 insertions(+), 53 deletions(-)
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 114cb2f..55048020 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -28,6 +28,7 @@ config CSKY
select GENERIC_SCHED_CLOCK
select GENERIC_SMP_IDLE_THREAD
select HAVE_ARCH_TRACEHOOK
+ select HAVE_ARCH_AUDITSYSCALL
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
@@ -39,6 +40,7 @@ config CSKY
select HAVE_PERF_EVENTS
select HAVE_DMA_API_DEBUG
select HAVE_DMA_CONTIGUOUS
+ select HAVE_SYSCALL_TRACEPOINTS
select MAY_HAVE_SPARSE_IRQ
select MODULES_USE_ELF_RELA if MODULES
select OF
diff --git a/arch/csky/include/asm/syscall.h b/arch/csky/include/asm/syscall.h
index d637445..bc484c9 100644
--- a/arch/csky/include/asm/syscall.h
+++ b/arch/csky/include/asm/syscall.h
@@ -8,6 +8,8 @@
#include <abi/regdef.h>
#include <uapi/linux/audit.h>
+extern void *sys_call_table[];
+
static inline int
syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
{
diff --git a/arch/csky/include/asm/thread_info.h b/arch/csky/include/asm/thread_info.h
index 0e9d035..207a932 100644
--- a/arch/csky/include/asm/thread_info.h
+++ b/arch/csky/include/asm/thread_info.h
@@ -51,29 +51,26 @@ static inline struct thread_info *current_thread_info(void)
#endif /* !__ASSEMBLY__ */
-/* entry.S relies on these definitions!
- * bits 0-5 are tested at every exception exit
- */
#define TIF_SIGPENDING 0 /* signal pending */
#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
#define TIF_SYSCALL_TRACE 5 /* syscall trace active */
-#define TIF_DELAYED_TRACE 14 /* single step a syscall */
+#define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */
+#define TIF_SYSCALL_AUDIT 7 /* syscall auditing */
#define TIF_POLLING_NRFLAG 16 /* poll_idle() is TIF_NEED_RESCHED */
#define TIF_MEMDIE 18 /* is terminating due to OOM killer */
-#define TIF_FREEZE 19 /* thread is freezing for suspend */
#define TIF_RESTORE_SIGMASK 20 /* restore signal mask in do_signal() */
#define TIF_SECCOMP 21 /* secure computing */
-#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
-#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
-#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
-#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
-#define _TIF_DELAYED_TRACE (1 << TIF_DELAYED_TRACE)
-#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
+#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
+#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
+#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
+#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT)
+#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
+#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_MEMDIE (1 << TIF_MEMDIE)
-#define _TIF_FREEZE (1 << TIF_FREEZE)
-#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
-#define _TIF_SECCOMP (1 << TIF_SECCOMP)
+#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
+#define _TIF_SECCOMP (1 << TIF_SECCOMP)
#endif /* _ASM_CSKY_THREAD_INFO_H */
diff --git a/arch/csky/include/asm/unistd.h b/arch/csky/include/asm/unistd.h
index 2844874..da7a182 100644
--- a/arch/csky/include/asm/unistd.h
+++ b/arch/csky/include/asm/unistd.h
@@ -2,3 +2,5 @@
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <uapi/asm/unistd.h>
+
+#define NR_syscalls (__NR_syscalls)
diff --git a/arch/csky/include/uapi/asm/ptrace.h b/arch/csky/include/uapi/asm/ptrace.h
index a4eaa8d..9bf5b1a 100644
--- a/arch/csky/include/uapi/asm/ptrace.h
+++ b/arch/csky/include/uapi/asm/ptrace.h
@@ -62,6 +62,11 @@ struct user_fp {
#define instruction_pointer(regs) ((regs)->pc)
#define profile_pc(regs) instruction_pointer(regs)
+static inline unsigned long regs_return_value(struct pt_regs *regs)
+{
+ return regs->a0;
+}
+
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
#endif /* _CSKY_PTRACE_H */
diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S
index 5137ed9..ebd1957 100644
--- a/arch/csky/kernel/entry.S
+++ b/arch/csky/kernel/entry.S
@@ -136,8 +136,8 @@ ENTRY(csky_systemcall)
bmaski r10, THREAD_SHIFT
andn r9, r10
ldw r8, (r9, TINFO_FLAGS)
- btsti r8, TIF_SYSCALL_TRACE
- bt 1f
+ andi r8, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)
+ bt csky_syscall_trace
#if defined(__CSKYABIV2__)
subi sp, 8
stw r5, (sp, 0x4)
@@ -150,10 +150,9 @@ ENTRY(csky_systemcall)
stw a0, (sp, LSAVE_A0) /* Save return value */
jmpi ret_from_exception
-1:
- movi a0, 0 /* enter system call */
- mov a1, sp /* sp = pt_regs pointer */
- jbsr syscall_trace
+csky_syscall_trace:
+ mov a0, sp /* sp = pt_regs pointer */
+ jbsr syscall_trace_enter
/* Prepare args before do system call */
ldw a0, (sp, LSAVE_A0)
ldw a1, (sp, LSAVE_A1)
@@ -173,9 +172,8 @@ ENTRY(csky_systemcall)
#endif
stw a0, (sp, LSAVE_A0) /* Save return value */
- movi a0, 1 /* leave system call */
- mov a1, sp /* right now, sp --> pt_regs */
- jbsr syscall_trace
+ mov a0, sp /* right now, sp --> pt_regs */
+ jbsr syscall_trace_exit
br ret_from_exception
ENTRY(ret_from_kernel_thread)
@@ -193,9 +191,8 @@ ENTRY(ret_from_fork)
movi r11_sig, 1
btsti r8, TIF_SYSCALL_TRACE
bf 3f
- movi a0, 1
- mov a1, sp /* sp = pt_regs pointer */
- jbsr syscall_trace
+ mov a0, sp /* sp = pt_regs pointer */
+ jbsr syscall_trace_exit
3:
jbsr ret_from_exception
diff --git a/arch/csky/kernel/ptrace.c b/arch/csky/kernel/ptrace.c
index f2f12ff..91bc74b 100644
--- a/arch/csky/kernel/ptrace.c
+++ b/arch/csky/kernel/ptrace.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#include <linux/audit.h>
#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/kernel.h>
@@ -11,6 +12,7 @@
#include <linux/sched/task_stack.h>
#include <linux/signal.h>
#include <linux/smp.h>
+#include <linux/tracehook.h>
#include <linux/uaccess.h>
#include <linux/user.h>
@@ -22,6 +24,9 @@
#include <abi/regdef.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
/* sets the trace bits. */
#define TRACE_MODE_SI (1 << 14)
#define TRACE_MODE_RUN 0
@@ -207,35 +212,26 @@ long arch_ptrace(struct task_struct *child, long request,
return ret;
}
-/*
- * If process's system calls is traces, do some corresponding handles in this
- * function before entering system call function and after exiting system call
- * function.
- */
-asmlinkage void syscall_trace(int why, struct pt_regs *regs)
+asmlinkage void syscall_trace_enter(struct pt_regs *regs)
{
- long saved_why;
- /*
- * Save saved_why, why is used to denote syscall entry/exit;
- * why = 0:entry, why = 1: exit
- */
- saved_why = regs->regs[SYSTRACE_SAVENUM];
- regs->regs[SYSTRACE_SAVENUM] = why;
-
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
- ? 0x80 : 0));
-
- /*
- * 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;
- }
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_entry(regs);
+
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, syscall_get_nr(current, regs));
+
+ audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3);
+}
+
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
+{
+ audit_syscall_exit(regs);
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, 0);
- regs->regs[SYSTRACE_SAVENUM] = saved_why;
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, syscall_get_return_value(current, regs));
}
extern void show_stack(struct task_struct *task, unsigned long *stack);
--
2.7.4