From 7413429e76970db29125812e0b7fe504e8904807 Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@redhat.com>
Date: Wed, 30 Jan 2008 13:31:48 +0100
Subject: [PATCH] --- yaml --- r: 80061 b: refs/heads/master c:
 c269f19617f508cc5c29c0b064c1a437d7011a46 h: refs/heads/master i:   80059:
 656874419b73e120262cb763b9139e2945f6b5c9 v: v3

---
 [refs]                       |  2 +-
 trunk/include/linux/compat.h |  7 ++++++
 trunk/kernel/ptrace.c        | 46 ++++++++++++++++++++++++++++++++++++
 3 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 2d5cedbcb9f0..559b7aef5f9c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 032d82d9065dec0e26718eca376c2029e4bd0595
+refs/heads/master: c269f19617f508cc5c29c0b064c1a437d7011a46
diff --git a/trunk/include/linux/compat.h b/trunk/include/linux/compat.h
index a907fbede6c3..d38655f2be70 100644
--- a/trunk/include/linux/compat.h
+++ b/trunk/include/linux/compat.h
@@ -247,6 +247,13 @@ extern int compat_ptrace_request(struct task_struct *child,
 				 compat_long_t request,
 				 compat_ulong_t addr, compat_ulong_t data);
 
+#ifdef __ARCH_WANT_COMPAT_SYS_PTRACE
+extern long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
+			       compat_ulong_t addr, compat_ulong_t data);
+asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
+				  compat_long_t addr, compat_long_t data);
+#endif	/* __ARCH_WANT_COMPAT_SYS_PTRACE */
+
 /*
  * epoll (fs/eventpoll.c) compat bits follow ...
  */
diff --git a/trunk/kernel/ptrace.c b/trunk/kernel/ptrace.c
index ed1c3d56c2cd..e6e9b8be4b05 100644
--- a/trunk/kernel/ptrace.c
+++ b/trunk/kernel/ptrace.c
@@ -644,4 +644,50 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request,
 
 	return ret;
 }
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PTRACE
+asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
+				  compat_long_t addr, compat_long_t data)
+{
+	struct task_struct *child;
+	long ret;
+
+	/*
+	 * This lock_kernel fixes a subtle race with suid exec
+	 */
+	lock_kernel();
+	if (request == PTRACE_TRACEME) {
+		ret = ptrace_traceme();
+		goto out;
+	}
+
+	child = ptrace_get_task_struct(pid);
+	if (IS_ERR(child)) {
+		ret = PTR_ERR(child);
+		goto out;
+	}
+
+	if (request == PTRACE_ATTACH) {
+		ret = ptrace_attach(child);
+		/*
+		 * Some architectures need to do book-keeping after
+		 * a ptrace attach.
+		 */
+		if (!ret)
+			arch_ptrace_attach(child);
+		goto out_put_task_struct;
+	}
+
+	ret = ptrace_check_attach(child, request == PTRACE_KILL);
+	if (!ret)
+		ret = compat_arch_ptrace(child, request, addr, data);
+
+ out_put_task_struct:
+	put_task_struct(child);
+ out:
+	unlock_kernel();
+	return ret;
+}
+#endif /* __ARCH_WANT_COMPAT_SYS_PTRACE */
+
 #endif	/* CONFIG_COMPAT */