ANDROID: GKI: net: add vendor hook to get the correct classid for net cls

android_vh_receive_sock -- The sock classid will be modified by current
task via SCM_RIGHTS, despite the sock's owning process having been assigned
to a specified cgroup, so we restore the classid with the original process's
classid.

android_vh_task_get_classid -- In cases where packet transmission involves
non-serving softirq, execution may occur within the Wi-Fi driver's RX thread
context. This requires retrieving the classid from the sock associated with
the sk_buff structure rather than deriving it from the task context.

_trace_android_vh_task_get_classid() -- trace_android_vh_task_get_classid
called in include/net/cls_cgroup.h will result to build error and visibility
issue of some struct. So we create wrapper func:_trace_android_vh_task_get_classid
for include/net/cls_cgroup.h to call.

Bug: 404485061
Change-Id: I519bcece243f271133bcae2b71e66d54446ebde2
Signed-off-by: Chenghao Zhao <zhaochenghao@honor.com>

drivers/android/vendor_hooks.c

@@ -349,6 +349,8 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_tcp_select_window);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_tcp_update_rtt);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_sk_alloc);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_sk_free);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_receive_sock);
+EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_task_get_classid);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_enable_thermal_genl_check);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_thermal_pm_notify_suspend);
 EXPORT_TRACEPOINT_SYMBOL_GPL(android_vh_alloc_pages_entry);

include/net/cls_cgroup.h

@@ -20,6 +20,8 @@ struct cgroup_cls_state {
 	u32 classid;
 };
 
+void _trace_android_vh_task_get_classid(const struct sk_buff *skb, u32 *classid);
+
 struct cgroup_cls_state *task_cls_state(struct task_struct *p);
 
 static inline u32 task_cls_classid(struct task_struct *p)
@@ -73,6 +75,8 @@ static inline u32 task_get_classid(const struct sk_buff *skb)
 		classid = sock_cgroup_classid(&sk->sk_cgrp_data);
 	}
 
+	_trace_android_vh_task_get_classid(skb, &classid);
+
 	return classid;
 }
 #else /* !CONFIG_CGROUP_NET_CLASSID */

include/trace/hooks/net.h

@@ -82,6 +82,10 @@ DECLARE_HOOK(android_vh_tcp_rcv_established_fast_path,
 	TP_PROTO(struct sock *sk), TP_ARGS(sk));
 DECLARE_HOOK(android_vh_tcp_rcv_established_slow_path,
 	TP_PROTO(struct sock *sk), TP_ARGS(sk));
+DECLARE_HOOK(android_vh_receive_sock,
+	TP_PROTO(struct sock *sk), TP_ARGS(sk));
+DECLARE_HOOK(android_vh_task_get_classid,
+	TP_PROTO(const struct sk_buff *skb, u32 *classid), TP_ARGS(skb, classid));
 struct net_device;
 DECLARE_HOOK(android_vh_dc_send_copy,
 	TP_PROTO(struct sk_buff *skb, struct net_device *dev), TP_ARGS(skb, dev));

net/core/netclassid_cgroup.c

@@ -12,6 +12,13 @@
 
 #include <net/cls_cgroup.h>
 #include <net/sock.h>
+#include <trace/hooks/net.h>
+
+void _trace_android_vh_task_get_classid(const struct sk_buff *skb, u32 *classid)
+{
+	trace_android_vh_task_get_classid(skb, classid);
+}
+EXPORT_SYMBOL_GPL(_trace_android_vh_task_get_classid);
 
 static inline struct cgroup_cls_state *css_cls_state(struct cgroup_subsys_state *css)
 {

net/core/sock.c

@@ -3414,6 +3414,7 @@ void __receive_sock(struct file *file)
 	if (sock) {
 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
 		sock_update_classid(&sock->sk->sk_cgrp_data);
+		trace_android_vh_receive_sock(sock->sk);
 	}
 }