Merge tag 'core-urgent-2022-04-03' of git://git.kernel.org/pub/scm/linux/kernel/git...

[linux-2.6-microblaze.git] / include / linux / ptrace.h

diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index 8aee294..15b3d17 100644 (file)
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -60,7 +60,7 @@ extern int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned
 extern void ptrace_disable(struct task_struct *);
 extern int ptrace_request(struct task_struct *child, long request,
                          unsigned long addr, unsigned long data);
-extern void ptrace_notify(int exit_code);
+extern int ptrace_notify(int exit_code, unsigned long message);
 extern void __ptrace_link(struct task_struct *child,
                          struct task_struct *new_parent,
                          const struct cred *ptracer_cred);
@@ -155,8 +155,7 @@ static inline bool ptrace_event_enabled(struct task_struct *task, int event)
 static inline void ptrace_event(int event, unsigned long message)
 {
        if (unlikely(ptrace_event_enabled(current, event))) {
-               current->ptrace_message = message;
-               ptrace_notify((event << 8) | SIGTRAP);
+               ptrace_notify((event << 8) | SIGTRAP, message);
        } else if (event == PTRACE_EVENT_EXEC) {
                /* legacy EXEC report via SIGTRAP */
                if ((current->ptrace & (PT_PTRACED|PT_SEIZED)) == PT_PTRACED)
@@ -413,4 +412,80 @@ static inline void user_single_step_report(struct pt_regs *regs)
 extern int task_current_syscall(struct task_struct *target, struct syscall_info *info);
 
 extern void sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact);
+
+/*
+ * ptrace report for syscall entry and exit looks identical.
+ */
+static inline int ptrace_report_syscall(unsigned long message)
+{
+       int ptrace = current->ptrace;
+       int signr;
+
+       if (!(ptrace & PT_PTRACED))
+               return 0;
+
+       signr = ptrace_notify(SIGTRAP | ((ptrace & PT_TRACESYSGOOD) ? 0x80 : 0),
+                             message);
+
+       /*
+        * 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 (signr)
+               send_sig(signr, current, 1);
+
+       return fatal_signal_pending(current);
+}
+
+/**
+ * ptrace_report_syscall_entry - task is about to attempt a system call
+ * @regs:              user register state of current task
+ *
+ * This will be called if %SYSCALL_WORK_SYSCALL_TRACE or
+ * %SYSCALL_WORK_SYSCALL_EMU have been set, when the current task has just
+ * entered the kernel for a system call.  Full user register state is
+ * available here.  Changing the values in @regs can affect the system
+ * call number and arguments to be tried.  It is safe to block here,
+ * preventing the system call from beginning.
+ *
+ * Returns zero normally, or nonzero if the calling arch code should abort
+ * the system call.  That must prevent normal entry so no system call is
+ * made.  If @task ever returns to user mode after this, its register state
+ * is unspecified, but should be something harmless like an %ENOSYS error
+ * return.  It should preserve enough information so that syscall_rollback()
+ * can work (see asm-generic/syscall.h).
+ *
+ * Called without locks, just after entering kernel mode.
+ */
+static inline __must_check int ptrace_report_syscall_entry(
+       struct pt_regs *regs)
+{
+       return ptrace_report_syscall(PTRACE_EVENTMSG_SYSCALL_ENTRY);
+}
+
+/**
+ * ptrace_report_syscall_exit - task has just finished a system call
+ * @regs:              user register state of current task
+ * @step:              nonzero if simulating single-step or block-step
+ *
+ * This will be called if %SYSCALL_WORK_SYSCALL_TRACE has been set, when
+ * the current task has just finished an attempted system call.  Full
+ * user register state is available here.  It is safe to block here,
+ * preventing signals from being processed.
+ *
+ * If @step is nonzero, this report is also in lieu of the normal
+ * trap that would follow the system call instruction because
+ * user_enable_block_step() or user_enable_single_step() was used.
+ * In this case, %SYSCALL_WORK_SYSCALL_TRACE might not be set.
+ *
+ * Called without locks, just before checking for pending signals.
+ */
+static inline void ptrace_report_syscall_exit(struct pt_regs *regs, int step)
+{
+       if (step)
+               user_single_step_report(regs);
+       else
+               ptrace_report_syscall(PTRACE_EVENTMSG_SYSCALL_EXIT);
+}
 #endif