Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c
index 571d824..ea9e734 100644
--- a/net/kcm/kcmsock.c
+++ b/net/kcm/kcmsock.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Kernel Connection Multiplexor
  *
  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2
- * as published by the Free Software Foundation.
  */
 
 #include <linux/bpf.h>
@@ -381,8 +378,12 @@
 {
 	struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp);
 	struct bpf_prog *prog = psock->bpf_prog;
+	int res;
 
-	return (*prog->bpf_func)(skb, prog->insnsi);
+	preempt_disable();
+	res = BPF_PROG_RUN(prog, skb);
+	preempt_enable();
+	return res;
 }
 
 static int kcm_read_sock_done(struct strparser *strp, int err)
@@ -638,15 +639,15 @@
 			frag_offset = 0;
 do_frag:
 			frag = &skb_shinfo(skb)->frags[fragidx];
-			if (WARN_ON(!frag->size)) {
+			if (WARN_ON(!skb_frag_size(frag))) {
 				ret = -EINVAL;
 				goto out;
 			}
 
 			ret = kernel_sendpage(psock->sk->sk_socket,
-					      frag->page.p,
-					      frag->page_offset + frag_offset,
-					      frag->size - frag_offset,
+					      skb_frag_page(frag),
+					      skb_frag_off(frag) + frag_offset,
+					      skb_frag_size(frag) - frag_offset,
 					      MSG_DONTWAIT);
 			if (ret <= 0) {
 				if (ret == -EAGAIN) {
@@ -681,7 +682,7 @@
 			sent += ret;
 			frag_offset += ret;
 			KCM_STATS_ADD(psock->stats.tx_bytes, ret);
-			if (frag_offset < frag->size) {
+			if (frag_offset < skb_frag_size(frag)) {
 				/* Not finished with this frag */
 				goto do_frag;
 			}
@@ -2036,13 +2037,13 @@
 
 	kcm_muxp = kmem_cache_create("kcm_mux_cache",
 				     sizeof(struct kcm_mux), 0,
-				     SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
+				     SLAB_HWCACHE_ALIGN, NULL);
 	if (!kcm_muxp)
 		goto fail;
 
 	kcm_psockp = kmem_cache_create("kcm_psock_cache",
 				       sizeof(struct kcm_psock), 0,
-					SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
+					SLAB_HWCACHE_ALIGN, NULL);
 	if (!kcm_psockp)
 		goto fail;
 
@@ -2054,14 +2055,14 @@
 	if (err)
 		goto fail;
 
-	err = sock_register(&kcm_family_ops);
-	if (err)
-		goto sock_register_fail;
-
 	err = register_pernet_device(&kcm_net_ops);
 	if (err)
 		goto net_ops_fail;
 
+	err = sock_register(&kcm_family_ops);
+	if (err)
+		goto sock_register_fail;
+
 	err = kcm_proc_init();
 	if (err)
 		goto proc_init_fail;
@@ -2069,12 +2070,12 @@
 	return 0;
 
 proc_init_fail:
-	unregister_pernet_device(&kcm_net_ops);
-
-net_ops_fail:
 	sock_unregister(PF_KCM);
 
 sock_register_fail:
+	unregister_pernet_device(&kcm_net_ops);
+
+net_ops_fail:
 	proto_unregister(&kcm_proto);
 
 fail:
@@ -2090,8 +2091,8 @@
 static void __exit kcm_exit(void)
 {
 	kcm_proc_exit();
-	unregister_pernet_device(&kcm_net_ops);
 	sock_unregister(PF_KCM);
+	unregister_pernet_device(&kcm_net_ops);
 	proto_unregister(&kcm_proto);
 	destroy_workqueue(kcm_wq);