signal: Simplify tracehook_report_syscall_exit
Replace user_single_step_siginfo with user_single_step_report
that allocates siginfo structure on the stack and sends it.
This allows tracehook_report_syscall_exit to become a simple
if statement that calls user_single_step_report or ptrace_report_syscall
depending on the value of step.
Update the default helper function now called user_single_step_report
to explicitly set si_code to SI_USER and to set si_uid and si_pid to 0.
The default helper has always been doing this (using memset) but it
was far from obvious.
The powerpc helper can now just call force_sig_fault.
The x86 helper can now just call send_sigtrap.
Unfortunately the default implementation of user_single_step_report
can not use force_sig_fault as it does not use a SIGTRAP si_code.
So it has to carefully setup the siginfo and use use force_sig_info.
The net result is code that is easier to understand and simpler
to maintain.
Ref: 85ec7fd9f8e5 ("ptrace: introduce user_single_step_siginfo() helper")
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index c85adb8..f651fa9 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -307,12 +307,9 @@
}
NOKPROBE_SYMBOL(die);
-void user_single_step_siginfo(struct task_struct *tsk,
- struct pt_regs *regs, siginfo_t *info)
+void user_single_step_report(struct pt_regs *regs)
{
- info->si_signo = SIGTRAP;
- info->si_code = TRAP_TRACE;
- info->si_addr = (void __user *)regs->nip;
+ force_sig_fault(SIGTRAP, TRAP_TRACE, (void __user *)regs->nip, current);
}
static void show_signal_msg(int signr, struct pt_regs *regs, int code,