From: Daniel Borkmann <daniel@iogearbox.net>
Date: Mon, 25 Sep 2017 02:25:50 +0200
Subject: bpf: rename bpf_compute_data_end into bpf_compute_data_pointers
Patch-mainline: v4.15-rc1
Git-commit: 6aaae2b6c4330a46204bca042f1d2f41e8e18dea
References: bsc#1109837

Just do the rename into bpf_compute_data_pointers() as we'll add
one more pointer here to recompute.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/linux/filter.h |    9 ++++++---
 net/bpf/test_run.c     |    2 +-
 net/core/filter.c      |   14 +++++++-------
 net/core/lwt_bpf.c     |    2 +-
 net/sched/act_bpf.c    |    4 ++--
 net/sched/cls_bpf.c    |    4 ++--
 6 files changed, 19 insertions(+), 16 deletions(-)

--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -499,10 +499,13 @@ struct xdp_buff {
 	void *data_hard_start;
 };
 
-/* compute the linear packet data range [data, data_end) which
- * will be accessed by cls_bpf, act_bpf and lwt programs
+/* Compute the linear packet data range [data, data_end) which
+ * will be accessed by various program types (cls_bpf, act_bpf,
+ * lwt, ...). Subsystems allowing direct data access must (!)
+ * ensure that cb[] area can be written to when BPF program is
+ * invoked (otherwise cb[] save/restore is necessary).
  */
-static inline void bpf_compute_data_end(struct sk_buff *skb)
+static inline void bpf_compute_data_pointers(struct sk_buff *skb)
 {
 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -133,7 +133,7 @@ int bpf_prog_test_run_skb(struct bpf_pro
 	if (is_l2)
 		__skb_push(skb, ETH_HLEN);
 	if (is_direct_pkt_access)
-		bpf_compute_data_end(skb);
+		bpf_compute_data_pointers(skb);
 	retval = bpf_test_run(prog, skb, repeat, &duration);
 	if (!is_l2)
 		__skb_push(skb, ETH_HLEN);
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1406,7 +1406,7 @@ static inline int bpf_try_make_writable(
 {
 	int err = __bpf_try_make_writable(skb, write_len);
 
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return err;
 }
 
@@ -1968,7 +1968,7 @@ BPF_CALL_3(bpf_skb_vlan_push, struct sk_
 	ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
 	bpf_pull_mac_rcsum(skb);
 
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return ret;
 }
 
@@ -1990,7 +1990,7 @@ BPF_CALL_1(bpf_skb_vlan_pop, struct sk_b
 	ret = skb_vlan_pop(skb);
 	bpf_pull_mac_rcsum(skb);
 
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return ret;
 }
 
@@ -2184,7 +2184,7 @@ BPF_CALL_3(bpf_skb_change_proto, struct
 	 * need to be verified first.
 	 */
 	ret = bpf_skb_proto_xlat(skb, proto);
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return ret;
 }
 
@@ -2309,7 +2309,7 @@ static int bpf_skb_adjust_net(struct sk_
 	ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
 		       bpf_skb_net_grow(skb, len_diff_abs);
 
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return ret;
 }
 
@@ -2400,7 +2400,7 @@ BPF_CALL_3(bpf_skb_change_tail, struct s
 			skb_gso_reset(skb);
 	}
 
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return ret;
 }
 
@@ -2440,7 +2440,7 @@ BPF_CALL_3(bpf_skb_change_head, struct s
 		skb_reset_mac_header(skb);
 	}
 
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	return 0;
 }
 
--- a/net/core/lwt_bpf.c
+++ b/net/core/lwt_bpf.c
@@ -51,7 +51,7 @@ static int run_lwt_bpf(struct sk_buff *s
 	 */
 	preempt_disable();
 	rcu_read_lock();
-	bpf_compute_data_end(skb);
+	bpf_compute_data_pointers(skb);
 	ret = bpf_prog_run_save_cb(lwt->prog, skb);
 	rcu_read_unlock();
 
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -50,11 +50,11 @@ static int tcf_bpf(struct sk_buff *skb,
 	filter = rcu_dereference(prog->filter);
 	if (at_ingress) {
 		__skb_push(skb, skb->mac_len);
-		bpf_compute_data_end(skb);
+		bpf_compute_data_pointers(skb);
 		filter_res = BPF_PROG_RUN(filter, skb);
 		__skb_pull(skb, skb->mac_len);
 	} else {
-		bpf_compute_data_end(skb);
+		bpf_compute_data_pointers(skb);
 		filter_res = BPF_PROG_RUN(filter, skb);
 	}
 	rcu_read_unlock();
--- a/net/sched/cls_bpf.c
+++ b/net/sched/cls_bpf.c
@@ -99,11 +99,11 @@ static int cls_bpf_classify(struct sk_bu
 		} else if (at_ingress) {
 			/* It is safe to push/pull even if skb_shared() */
 			__skb_push(skb, skb->mac_len);
-			bpf_compute_data_end(skb);
+			bpf_compute_data_pointers(skb);
 			filter_res = BPF_PROG_RUN(prog->filter, skb);
 			__skb_pull(skb, skb->mac_len);
 		} else {
-			bpf_compute_data_end(skb);
+			bpf_compute_data_pointers(skb);
 			filter_res = BPF_PROG_RUN(prog->filter, skb);
 		}