X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=kernel%2Fptrace.c;h=17ae54da0ec2efb010184c38daf1c43953a6745c;hb=91c2e0bcae72a3086c698b5de2b950b885abb0e6;hp=acbd28424d812040e060a82ae2d6f28e156e5fe1;hpb=bf61c8840efe60fd8f91446860b63338fb424158;p=firefly-linux-kernel-4.4.55.git

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index acbd28424d81..17ae54da0ec2 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -24,6 +24,7 @@
 #include <linux/regset.h>
 #include <linux/hw_breakpoint.h>
 #include <linux/cn_proc.h>
+#include <linux/compat.h>
 
 
 static int ptrace_trapping_sleep_fn(void *flags)
@@ -618,6 +619,81 @@ static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info)
 	return error;
 }
 
+static int ptrace_peek_siginfo(struct task_struct *child,
+				unsigned long addr,
+				unsigned long data)
+{
+	struct ptrace_peeksiginfo_args arg;
+	struct sigpending *pending;
+	struct sigqueue *q;
+	int ret, i;
+
+	ret = copy_from_user(&arg, (void __user *) addr,
+				sizeof(struct ptrace_peeksiginfo_args));
+	if (ret)
+		return -EFAULT;
+
+	if (arg.flags & ~PTRACE_PEEKSIGINFO_SHARED)
+		return -EINVAL; /* unknown flags */
+
+	if (arg.nr < 0)
+		return -EINVAL;
+
+	if (arg.flags & PTRACE_PEEKSIGINFO_SHARED)
+		pending = &child->signal->shared_pending;
+	else
+		pending = &child->pending;
+
+	for (i = 0; i < arg.nr; ) {
+		siginfo_t info;
+		s32 off = arg.off + i;
+
+		spin_lock_irq(&child->sighand->siglock);
+		list_for_each_entry(q, &pending->list, list) {
+			if (!off--) {
+				copy_siginfo(&info, &q->info);
+				break;
+			}
+		}
+		spin_unlock_irq(&child->sighand->siglock);
+
+		if (off >= 0) /* beyond the end of the list */
+			break;
+
+#ifdef CONFIG_COMPAT
+		if (unlikely(is_compat_task())) {
+			compat_siginfo_t __user *uinfo = compat_ptr(data);
+
+			ret = copy_siginfo_to_user32(uinfo, &info);
+			ret |= __put_user(info.si_code, &uinfo->si_code);
+		} else
+#endif
+		{
+			siginfo_t __user *uinfo = (siginfo_t __user *) data;
+
+			ret = copy_siginfo_to_user(uinfo, &info);
+			ret |= __put_user(info.si_code, &uinfo->si_code);
+		}
+
+		if (ret) {
+			ret = -EFAULT;
+			break;
+		}
+
+		data += sizeof(siginfo_t);
+		i++;
+
+		if (signal_pending(current))
+			break;
+
+		cond_resched();
+	}
+
+	if (i > 0)
+		return i;
+
+	return ret;
+}
 
 #ifdef PTRACE_SINGLESTEP
 #define is_singlestep(request)		((request) == PTRACE_SINGLESTEP)
@@ -748,6 +824,10 @@ int ptrace_request(struct task_struct *child, long request,
 		ret = put_user(child->ptrace_message, datalp);
 		break;
 
+	case PTRACE_PEEKSIGINFO:
+		ret = ptrace_peek_siginfo(child, addr, data);
+		break;
+
 	case PTRACE_GETSIGINFO:
 		ret = ptrace_getsiginfo(child, &siginfo);
 		if (!ret)