netfilter: nf_log: move log buffering to core logging

This patch moves Eric Dumazet's log buffer implementation from the
xt_log.h header file to the core net/netfilter/nf_log.c. This also
includes the renaming of the structure and functions to avoid possible
undesired namespace clashes.

This change allows us to use it from the arp and bridge packet logging
implementation in follow up patches.

2 files changed, 211 insertions, 147 deletions

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 7a29a3a46172..0b6b2c874199 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -157,6 +157,63 @@ void nf_log_packet(struct net *net,
 }
 EXPORT_SYMBOL(nf_log_packet);
 
+#define S_SIZE (1024 - (sizeof(unsigned int) + 1))
+
+struct nf_log_buf {
+	unsigned int	count;
+	char		buf[S_SIZE + 1];
+};
+static struct nf_log_buf emergency, *emergency_ptr = &emergency;
+
+__printf(2, 3) int nf_log_buf_add(struct nf_log_buf *m, const char *f, ...)
+{
+	va_list args;
+	int len;
+
+	if (likely(m->count < S_SIZE)) {
+		va_start(args, f);
+		len = vsnprintf(m->buf + m->count, S_SIZE - m->count, f, args);
+		va_end(args);
+		if (likely(m->count + len < S_SIZE)) {
+			m->count += len;
+			return 0;
+		}
+	}
+	m->count = S_SIZE;
+	printk_once(KERN_ERR KBUILD_MODNAME " please increase S_SIZE\n");
+	return -1;
+}
+EXPORT_SYMBOL_GPL(nf_log_buf_add);
+
+struct nf_log_buf *nf_log_buf_open(void)
+{
+	struct nf_log_buf *m = kmalloc(sizeof(*m), GFP_ATOMIC);
+
+	if (unlikely(!m)) {
+		local_bh_disable();
+		do {
+			m = xchg(&emergency_ptr, NULL);
+		} while (!m);
+	}
+	m->count = 0;
+	return m;
+}
+EXPORT_SYMBOL_GPL(nf_log_buf_open);
+
+void nf_log_buf_close(struct nf_log_buf *m)
+{
+	m->buf[m->count] = 0;
+	printk("%s\n", m->buf);
+
+	if (likely(m != &emergency))
+		kfree(m);
+	else {
+		emergency_ptr = m;
+		local_bh_enable();
+	}
+}
+EXPORT_SYMBOL_GPL(nf_log_buf_close);
+
 #ifdef CONFIG_PROC_FS
 static void *seq_start(struct seq_file *seq, loff_t *pos)
 {
diff --git a/net/netfilter/xt_LOG.c b/net/netfilter/xt_LOG.c
index e668d9797cf3..649b85fc5463 100644
--- a/net/netfilter/xt_LOG.c
+++ b/net/netfilter/xt_LOG.c
@@ -27,7 +27,6 @@
 #include <linux/netfilter/xt_LOG.h>
 #include <linux/netfilter_ipv6/ip6_tables.h>
 #include <net/netfilter/nf_log.h>
-#include <net/netfilter/xt_log.h>
 
 static struct nf_loginfo default_loginfo = {
 	.type	= NF_LOG_TYPE_LOG,
@@ -39,7 +38,7 @@ static struct nf_loginfo default_loginfo = {
 	},
 };
 
-static int dump_udp_header(struct sbuff *m, const struct sk_buff *skb,
+static int dump_udp_header(struct nf_log_buf *m, const struct sk_buff *skb,
 			   u8 proto, int fragment, unsigned int offset)
 {
 	struct udphdr _udph;
@@ -47,9 +46,9 @@ static int dump_udp_header(struct sbuff *m, const struct sk_buff *skb,
 
 	if (proto == IPPROTO_UDP)
 		/* Max length: 10 "PROTO=UDP "     */
-		sb_add(m, "PROTO=UDP ");
+		nf_log_buf_add(m, "PROTO=UDP ");
 	else	/* Max length: 14 "PROTO=UDPLITE " */
-		sb_add(m, "PROTO=UDPLITE ");
+		nf_log_buf_add(m, "PROTO=UDPLITE ");
 
 	if (fragment)
 		goto out;
@@ -57,20 +56,20 @@ static int dump_udp_header(struct sbuff *m, const struct sk_buff *skb,
 	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
 	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
 	if (uh == NULL) {
-		sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
+		nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
 
 		return 1;
 	}
 
 	/* Max length: 20 "SPT=65535 DPT=65535 " */
-	sb_add(m, "SPT=%u DPT=%u LEN=%u ", ntohs(uh->source), ntohs(uh->dest),
-		ntohs(uh->len));
+	nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ",
+		       ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
 
 out:
 	return 0;
 }
 
-static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb,
+static int dump_tcp_header(struct nf_log_buf *m, const struct sk_buff *skb,
 			   u8 proto, int fragment, unsigned int offset,
 			   unsigned int logflags)
 {
@@ -78,7 +77,7 @@ static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb,
 	const struct tcphdr *th;
 
 	/* Max length: 10 "PROTO=TCP " */
-	sb_add(m, "PROTO=TCP ");
+	nf_log_buf_add(m, "PROTO=TCP ");
 
 	if (fragment)
 		return 0;
@@ -86,40 +85,43 @@ static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb,
 	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
 	th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
 	if (th == NULL) {
-		sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
+		nf_log_buf_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset);
 		return 1;
 	}
 
 	/* Max length: 20 "SPT=65535 DPT=65535 " */
-	sb_add(m, "SPT=%u DPT=%u ", ntohs(th->source), ntohs(th->dest));
+	nf_log_buf_add(m, "SPT=%u DPT=%u ",
+		       ntohs(th->source), ntohs(th->dest));
 	/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
-	if (logflags & XT_LOG_TCPSEQ)
-		sb_add(m, "SEQ=%u ACK=%u ", ntohl(th->seq), ntohl(th->ack_seq));
+	if (logflags & XT_LOG_TCPSEQ) {
+		nf_log_buf_add(m, "SEQ=%u ACK=%u ",
+			       ntohl(th->seq), ntohl(th->ack_seq));
+	}
 
 	/* Max length: 13 "WINDOW=65535 " */
-	sb_add(m, "WINDOW=%u ", ntohs(th->window));
+	nf_log_buf_add(m, "WINDOW=%u ", ntohs(th->window));
 	/* Max length: 9 "RES=0x3C " */
-	sb_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) &
+	nf_log_buf_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) &
 					    TCP_RESERVED_BITS) >> 22));
 	/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
 	if (th->cwr)
-		sb_add(m, "CWR ");
+		nf_log_buf_add(m, "CWR ");
 	if (th->ece)
-		sb_add(m, "ECE ");
+		nf_log_buf_add(m, "ECE ");
 	if (th->urg)
-		sb_add(m, "URG ");
+		nf_log_buf_add(m, "URG ");
 	if (th->ack)
-		sb_add(m, "ACK ");
+		nf_log_buf_add(m, "ACK ");
 	if (th->psh)
-		sb_add(m, "PSH ");
+		nf_log_buf_add(m, "PSH ");
 	if (th->rst)
-		sb_add(m, "RST ");
+		nf_log_buf_add(m, "RST ");
 	if (th->syn)
-		sb_add(m, "SYN ");
+		nf_log_buf_add(m, "SYN ");
 	if (th->fin)
-		sb_add(m, "FIN ");
+		nf_log_buf_add(m, "FIN ");
 	/* Max length: 11 "URGP=65535 " */
-	sb_add(m, "URGP=%u ", ntohs(th->urg_ptr));
+	nf_log_buf_add(m, "URGP=%u ", ntohs(th->urg_ptr));
 
 	if ((logflags & XT_LOG_TCPOPT) && th->doff*4 > sizeof(struct tcphdr)) {
 		u_int8_t _opt[60 - sizeof(struct tcphdr)];
@@ -130,22 +132,22 @@ static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb,
 		op = skb_header_pointer(skb, offset + sizeof(struct tcphdr),
 					optsize, _opt);
 		if (op == NULL) {
-			sb_add(m, "OPT (TRUNCATED)");
+			nf_log_buf_add(m, "OPT (TRUNCATED)");
 			return 1;
 		}
 
 		/* Max length: 127 "OPT (" 15*4*2chars ") " */
-		sb_add(m, "OPT (");
+		nf_log_buf_add(m, "OPT (");
 		for (i = 0; i < optsize; i++)
-			sb_add(m, "%02X", op[i]);
+			nf_log_buf_add(m, "%02X", op[i]);
 
-		sb_add(m, ") ");
+		nf_log_buf_add(m, ") ");
 	}
 
 	return 0;
 }
 
-static void dump_sk_uid_gid(struct sbuff *m, struct sock *sk)
+static void dump_sk_uid_gid(struct nf_log_buf *m, struct sock *sk)
 {
 	if (!sk || sk->sk_state == TCP_TIME_WAIT)
 		return;
@@ -153,7 +155,7 @@ static void dump_sk_uid_gid(struct sbuff *m, struct sock *sk)
 	read_lock_bh(&sk->sk_callback_lock);
 	if (sk->sk_socket && sk->sk_socket->file) {
 		const struct cred *cred = sk->sk_socket->file->f_cred;
-		sb_add(m, "UID=%u GID=%u ",
+		nf_log_buf_add(m, "UID=%u GID=%u ",
 			from_kuid_munged(&init_user_ns, cred->fsuid),
 			from_kgid_munged(&init_user_ns, cred->fsgid));
 	}
@@ -161,10 +163,9 @@ static void dump_sk_uid_gid(struct sbuff *m, struct sock *sk)
 }
 
 /* One level of recursion won't kill us */
-static void dump_ipv4_packet(struct sbuff *m,
-			const struct nf_loginfo *info,
-			const struct sk_buff *skb,
-			unsigned int iphoff)
+static void dump_ipv4_packet(struct nf_log_buf *m,
+			     const struct nf_loginfo *info,
+			     const struct sk_buff *skb, unsigned int iphoff)
 {
 	struct iphdr _iph;
 	const struct iphdr *ih;
@@ -177,32 +178,32 @@ static void dump_ipv4_packet(struct sbuff *m,
 
 	ih = skb_header_pointer(skb, iphoff, sizeof(_iph), &_iph);
 	if (ih == NULL) {
-		sb_add(m, "TRUNCATED");
+		nf_log_buf_add(m, "TRUNCATED");
 		return;
 	}
 
 	/* Important fields:
 	 * TOS, len, DF/MF, fragment offset, TTL, src, dst, options. */
 	/* Max length: 40 "SRC=255.255.255.255 DST=255.255.255.255 " */
-	sb_add(m, "SRC=%pI4 DST=%pI4 ",
+	nf_log_buf_add(m, "SRC=%pI4 DST=%pI4 ",
 	       &ih->saddr, &ih->daddr);
 
 	/* Max length: 46 "LEN=65535 TOS=0xFF PREC=0xFF TTL=255 ID=65535 " */
-	sb_add(m, "LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ",
+	nf_log_buf_add(m, "LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ",
 	       ntohs(ih->tot_len), ih->tos & IPTOS_TOS_MASK,
 	       ih->tos & IPTOS_PREC_MASK, ih->ttl, ntohs(ih->id));
 
 	/* Max length: 6 "CE DF MF " */
 	if (ntohs(ih->frag_off) & IP_CE)
-		sb_add(m, "CE ");
+		nf_log_buf_add(m, "CE ");
 	if (ntohs(ih->frag_off) & IP_DF)
-		sb_add(m, "DF ");
+		nf_log_buf_add(m, "DF ");
 	if (ntohs(ih->frag_off) & IP_MF)
-		sb_add(m, "MF ");
+		nf_log_buf_add(m, "MF ");
 
 	/* Max length: 11 "FRAG:65535 " */
 	if (ntohs(ih->frag_off) & IP_OFFSET)
-		sb_add(m, "FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);
+		nf_log_buf_add(m, "FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);
 
 	if ((logflags & XT_LOG_IPOPT) &&
 	    ih->ihl * 4 > sizeof(struct iphdr)) {
@@ -214,15 +215,15 @@ static void dump_ipv4_packet(struct sbuff *m,
 		op = skb_header_pointer(skb, iphoff+sizeof(_iph),
 					optsize, _opt);
 		if (op == NULL) {
-			sb_add(m, "TRUNCATED");
+			nf_log_buf_add(m, "TRUNCATED");
 			return;
 		}
 
 		/* Max length: 127 "OPT (" 15*4*2chars ") " */
-		sb_add(m, "OPT (");
+		nf_log_buf_add(m, "OPT (");
 		for (i = 0; i < optsize; i++)
-			sb_add(m, "%02X", op[i]);
-		sb_add(m, ") ");
+			nf_log_buf_add(m, "%02X", op[i]);
+		nf_log_buf_add(m, ") ");
 	}
 
 	switch (ih->protocol) {
@@ -261,7 +262,7 @@ static void dump_ipv4_packet(struct sbuff *m,
 			    [ICMP_ADDRESSREPLY] = 12 };
 
 		/* Max length: 11 "PROTO=ICMP " */
-		sb_add(m, "PROTO=ICMP ");
+		nf_log_buf_add(m, "PROTO=ICMP ");
 
 		if (ntohs(ih->frag_off) & IP_OFFSET)
 			break;
@@ -270,19 +271,19 @@ static void dump_ipv4_packet(struct sbuff *m,
 		ich = skb_header_pointer(skb, iphoff + ih->ihl * 4,
 					 sizeof(_icmph), &_icmph);
 		if (ich == NULL) {
-			sb_add(m, "INCOMPLETE [%u bytes] ",
-			       skb->len - iphoff - ih->ihl*4);
+			nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
+				       skb->len - iphoff - ih->ihl*4);
 			break;
 		}
 
 		/* Max length: 18 "TYPE=255 CODE=255 " */
-		sb_add(m, "TYPE=%u CODE=%u ", ich->type, ich->code);
+		nf_log_buf_add(m, "TYPE=%u CODE=%u ", ich->type, ich->code);
 
 		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
 		if (ich->type <= NR_ICMP_TYPES &&
 		    required_len[ich->type] &&
 		    skb->len-iphoff-ih->ihl*4 < required_len[ich->type]) {
-			sb_add(m, "INCOMPLETE [%u bytes] ",
+			nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
 			       skb->len - iphoff - ih->ihl*4);
 			break;
 		}
@@ -291,35 +292,37 @@ static void dump_ipv4_packet(struct sbuff *m,
 		case ICMP_ECHOREPLY:
 		case ICMP_ECHO:
 			/* Max length: 19 "ID=65535 SEQ=65535 " */
-			sb_add(m, "ID=%u SEQ=%u ",
+			nf_log_buf_add(m, "ID=%u SEQ=%u ",
 			       ntohs(ich->un.echo.id),
 			       ntohs(ich->un.echo.sequence));
 			break;
 
 		case ICMP_PARAMETERPROB:
 			/* Max length: 14 "PARAMETER=255 " */
-			sb_add(m, "PARAMETER=%u ",
+			nf_log_buf_add(m, "PARAMETER=%u ",
 			       ntohl(ich->un.gateway) >> 24);
 			break;
 		case ICMP_REDIRECT:
 			/* Max length: 24 "GATEWAY=255.255.255.255 " */
-			sb_add(m, "GATEWAY=%pI4 ", &ich->un.gateway);
+			nf_log_buf_add(m, "GATEWAY=%pI4 ", &ich->un.gateway);
 			/* Fall through */
 		case ICMP_DEST_UNREACH:
 		case ICMP_SOURCE_QUENCH:
 		case ICMP_TIME_EXCEEDED:
 			/* Max length: 3+maxlen */
 			if (!iphoff) { /* Only recurse once. */
-				sb_add(m, "[");
+				nf_log_buf_add(m, "[");
 				dump_ipv4_packet(m, info, skb,
 					    iphoff + ih->ihl*4+sizeof(_icmph));
-				sb_add(m, "] ");
+				nf_log_buf_add(m, "] ");
 			}
 
 			/* Max length: 10 "MTU=65535 " */
 			if (ich->type == ICMP_DEST_UNREACH &&
-			    ich->code == ICMP_FRAG_NEEDED)
-				sb_add(m, "MTU=%u ", ntohs(ich->un.frag.mtu));
+			    ich->code == ICMP_FRAG_NEEDED) {
+				nf_log_buf_add(m, "MTU=%u ",
+					       ntohs(ich->un.frag.mtu));
+			}
 		}
 		break;
 	}
@@ -332,19 +335,19 @@ static void dump_ipv4_packet(struct sbuff *m,
 			break;
 
 		/* Max length: 9 "PROTO=AH " */
-		sb_add(m, "PROTO=AH ");
+		nf_log_buf_add(m, "PROTO=AH ");
 
 		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
 		ah = skb_header_pointer(skb, iphoff+ih->ihl*4,
 					sizeof(_ahdr), &_ahdr);
 		if (ah == NULL) {
-			sb_add(m, "INCOMPLETE [%u bytes] ",
-			       skb->len - iphoff - ih->ihl*4);
+			nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
+				       skb->len - iphoff - ih->ihl*4);
 			break;
 		}
 
 		/* Length: 15 "SPI=0xF1234567 " */
-		sb_add(m, "SPI=0x%x ", ntohl(ah->spi));
+		nf_log_buf_add(m, "SPI=0x%x ", ntohl(ah->spi));
 		break;
 	}
 	case IPPROTO_ESP: {
@@ -352,7 +355,7 @@ static void dump_ipv4_packet(struct sbuff *m,
 		const struct ip_esp_hdr *eh;
 
 		/* Max length: 10 "PROTO=ESP " */
-		sb_add(m, "PROTO=ESP ");
+		nf_log_buf_add(m, "PROTO=ESP ");
 
 		if (ntohs(ih->frag_off) & IP_OFFSET)
 			break;
@@ -361,18 +364,18 @@ static void dump_ipv4_packet(struct sbuff *m,
 		eh = skb_header_pointer(skb, iphoff+ih->ihl*4,
 					sizeof(_esph), &_esph);
 		if (eh == NULL) {
-			sb_add(m, "INCOMPLETE [%u bytes] ",
-			       skb->len - iphoff - ih->ihl*4);
+			nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
+				       skb->len - iphoff - ih->ihl*4);
 			break;
 		}
 
 		/* Length: 15 "SPI=0xF1234567 " */
-		sb_add(m, "SPI=0x%x ", ntohl(eh->spi));
+		nf_log_buf_add(m, "SPI=0x%x ", ntohl(eh->spi));
 		break;
 	}
 	/* Max length: 10 "PROTO 255 " */
 	default:
-		sb_add(m, "PROTO=%u ", ih->protocol);
+		nf_log_buf_add(m, "PROTO=%u ", ih->protocol);
 	}
 
 	/* Max length: 15 "UID=4294967295 " */
@@ -381,7 +384,7 @@ static void dump_ipv4_packet(struct sbuff *m,
 
 	/* Max length: 16 "MARK=0xFFFFFFFF " */
 	if (!iphoff && skb->mark)
-		sb_add(m, "MARK=0x%x ", skb->mark);
+		nf_log_buf_add(m, "MARK=0x%x ", skb->mark);
 
 	/* Proto    Max log string length */
 	/* IP:      40+46+6+11+127 = 230 */
@@ -398,9 +401,9 @@ static void dump_ipv4_packet(struct sbuff *m,
 	/* maxlen = 230+   91  + 230 + 252 = 803 */
 }
 
-static void dump_ipv4_mac_header(struct sbuff *m,
-			    const struct nf_loginfo *info,
-			    const struct sk_buff *skb)
+static void dump_ipv4_mac_header(struct nf_log_buf *m,
+				 const struct nf_loginfo *info,
+				 const struct sk_buff *skb)
 {
 	struct net_device *dev = skb->dev;
 	unsigned int logflags = 0;
@@ -413,30 +416,30 @@ static void dump_ipv4_mac_header(struct sbuff *m,
 
 	switch (dev->type) {
 	case ARPHRD_ETHER:
-		sb_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
-		       eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
-		       ntohs(eth_hdr(skb)->h_proto));
+		nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
+			       eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
+			       ntohs(eth_hdr(skb)->h_proto));
 		return;
 	default:
 		break;
 	}
 
 fallback:
-	sb_add(m, "MAC=");
+	nf_log_buf_add(m, "MAC=");
 	if (dev->hard_header_len &&
 	    skb->mac_header != skb->network_header) {
 		const unsigned char *p = skb_mac_header(skb);
 		unsigned int i;
 
-		sb_add(m, "%02x", *p++);
+		nf_log_buf_add(m, "%02x", *p++);
 		for (i = 1; i < dev->hard_header_len; i++, p++)
-			sb_add(m, ":%02x", *p);
+			nf_log_buf_add(m, ":%02x", *p);
 	}
-	sb_add(m, " ");
+	nf_log_buf_add(m, " ");
 }
 
 static void
-log_packet_common(struct sbuff *m,
+log_packet_common(struct nf_log_buf *m,
 		  u_int8_t pf,
 		  unsigned int hooknum,
 		  const struct sk_buff *skb,
@@ -445,10 +448,10 @@ log_packet_common(struct sbuff *m,
 		  const struct nf_loginfo *loginfo,
 		  const char *prefix)
 {
-	sb_add(m, KERN_SOH "%c%sIN=%s OUT=%s ",
-	       '0' + loginfo->u.log.level, prefix,
-	       in ? in->name : "",
-	       out ? out->name : "");
+	nf_log_buf_add(m, KERN_SOH "%c%sIN=%s OUT=%s ",
+		       '0' + loginfo->u.log.level, prefix,
+		       in ? in->name : "",
+		       out ? out->name : "");
 #ifdef CONFIG_BRIDGE_NETFILTER
 	if (skb->nf_bridge) {
 		const struct net_device *physindev;
@@ -456,10 +459,10 @@ log_packet_common(struct sbuff *m,
 
 		physindev = skb->nf_bridge->physindev;
 		if (physindev && in != physindev)
-			sb_add(m, "PHYSIN=%s ", physindev->name);
+			nf_log_buf_add(m, "PHYSIN=%s ", physindev->name);
 		physoutdev = skb->nf_bridge->physoutdev;
 		if (physoutdev && out != physoutdev)
-			sb_add(m, "PHYSOUT=%s ", physoutdev->name);
+			nf_log_buf_add(m, "PHYSOUT=%s ", physoutdev->name);
 	}
 #endif
 }
@@ -475,13 +478,13 @@ ipt_log_packet(struct net *net,
 	       const struct nf_loginfo *loginfo,
 	       const char *prefix)
 {
-	struct sbuff *m;
+	struct nf_log_buf *m;
 
 	/* FIXME: Disabled from containers until syslog ns is supported */
 	if (!net_eq(net, &init_net))
 		return;
 
-	m = sb_open();
+	m = nf_log_buf_open();
 
 	if (!loginfo)
 		loginfo = &default_loginfo;
@@ -493,15 +496,15 @@ ipt_log_packet(struct net *net,
 
 	dump_ipv4_packet(m, loginfo, skb, 0);
 
-	sb_close(m);
+	nf_log_buf_close(m);
 }
 
 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
 /* One level of recursion won't kill us */
-static void dump_ipv6_packet(struct sbuff *m,
-			const struct nf_loginfo *info,
-			const struct sk_buff *skb, unsigned int ip6hoff,
-			int recurse)
+static void dump_ipv6_packet(struct nf_log_buf *m,
+			     const struct nf_loginfo *info,
+			     const struct sk_buff *skb, unsigned int ip6hoff,
+			     int recurse)
 {
 	u_int8_t currenthdr;
 	int fragment;
@@ -518,19 +521,18 @@ static void dump_ipv6_packet(struct sbuff *m,
 
 	ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h);
 	if (ih == NULL) {
-		sb_add(m, "TRUNCATED");
+		nf_log_buf_add(m, "TRUNCATED");
 		return;
 	}
 
 	/* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
-	sb_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);
+	nf_log_buf_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);
 
 	/* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
-	sb_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
-	       ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
-	       (ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20,
-	       ih->hop_limit,
-	       (ntohl(*(__be32 *)ih) & 0x000fffff));
+	nf_log_buf_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
+		       ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
+		       (ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20,
+		       ih->hop_limit, (ntohl(*(__be32 *)ih) & 0x000fffff));
 
 	fragment = 0;
 	ptr = ip6hoff + sizeof(struct ipv6hdr);
@@ -541,35 +543,35 @@ static void dump_ipv6_packet(struct sbuff *m,
 
 		hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
 		if (hp == NULL) {
-			sb_add(m, "TRUNCATED");
+			nf_log_buf_add(m, "TRUNCATED");
 			return;
 		}
 
 		/* Max length: 48 "OPT (...) " */
 		if (logflags & XT_LOG_IPOPT)
-			sb_add(m, "OPT ( ");
+			nf_log_buf_add(m, "OPT ( ");
 
 		switch (currenthdr) {
 		case IPPROTO_FRAGMENT: {
 			struct frag_hdr _fhdr;
 			const struct frag_hdr *fh;
 
-			sb_add(m, "FRAG:");
+			nf_log_buf_add(m, "FRAG:");
 			fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
 						&_fhdr);
 			if (fh == NULL) {
-				sb_add(m, "TRUNCATED ");
+				nf_log_buf_add(m, "TRUNCATED ");
 				return;
 			}
 
 			/* Max length: 6 "65535 " */
-			sb_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);
+			nf_log_buf_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);
 
 			/* Max length: 11 "INCOMPLETE " */
 			if (fh->frag_off & htons(0x0001))
-				sb_add(m, "INCOMPLETE ");
+				nf_log_buf_add(m, "INCOMPLETE ");
 
-			sb_add(m, "ID:%08x ", ntohl(fh->identification));
+			nf_log_buf_add(m, "ID:%08x ", ntohl(fh->identification));
 
 			if (ntohs(fh->frag_off) & 0xFFF8)
 				fragment = 1;
@@ -583,7 +585,7 @@ static void dump_ipv6_packet(struct sbuff *m,
 		case IPPROTO_HOPOPTS:
 			if (fragment) {
 				if (logflags & XT_LOG_IPOPT)
-					sb_add(m, ")");
+					nf_log_buf_add(m, ")");
 				return;
 			}
 			hdrlen = ipv6_optlen(hp);
@@ -595,10 +597,10 @@ static void dump_ipv6_packet(struct sbuff *m,
 				const struct ip_auth_hdr *ah;
 
 				/* Max length: 3 "AH " */
-				sb_add(m, "AH ");
+				nf_log_buf_add(m, "AH ");
 
 				if (fragment) {
-					sb_add(m, ")");
+					nf_log_buf_add(m, ")");
 					return;
 				}
 
@@ -609,13 +611,13 @@ static void dump_ipv6_packet(struct sbuff *m,
 					 * Max length: 26 "INCOMPLETE [65535
 					 *  bytes] )"
 					 */
-					sb_add(m, "INCOMPLETE [%u bytes] )",
-					       skb->len - ptr);
+					nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
+						       skb->len - ptr);
 					return;
 				}
 
 				/* Length: 15 "SPI=0xF1234567 */
-				sb_add(m, "SPI=0x%x ", ntohl(ah->spi));
+				nf_log_buf_add(m, "SPI=0x%x ", ntohl(ah->spi));
 
 			}
 
@@ -627,10 +629,10 @@ static void dump_ipv6_packet(struct sbuff *m,
 				const struct ip_esp_hdr *eh;
 
 				/* Max length: 4 "ESP " */
-				sb_add(m, "ESP ");
+				nf_log_buf_add(m, "ESP ");
 
 				if (fragment) {
-					sb_add(m, ")");
+					nf_log_buf_add(m, ")");
 					return;
 				}
 
@@ -640,23 +642,23 @@ static void dump_ipv6_packet(struct sbuff *m,
 				eh = skb_header_pointer(skb, ptr, sizeof(_esph),
 							&_esph);
 				if (eh == NULL) {
-					sb_add(m, "INCOMPLETE [%u bytes] )",
-					       skb->len - ptr);
+					nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
+						       skb->len - ptr);
 					return;
 				}
 
 				/* Length: 16 "SPI=0xF1234567 )" */
-				sb_add(m, "SPI=0x%x )", ntohl(eh->spi));
+				nf_log_buf_add(m, "SPI=0x%x )", ntohl(eh->spi));
 
 			}
 			return;
 		default:
 			/* Max length: 20 "Unknown Ext Hdr 255" */
-			sb_add(m, "Unknown Ext Hdr %u", currenthdr);
+			nf_log_buf_add(m, "Unknown Ext Hdr %u", currenthdr);
 			return;
 		}
 		if (logflags & XT_LOG_IPOPT)
-			sb_add(m, ") ");
+			nf_log_buf_add(m, ") ");
 
 		currenthdr = hp->nexthdr;
 		ptr += hdrlen;
@@ -678,7 +680,7 @@ static void dump_ipv6_packet(struct sbuff *m,
 		const struct icmp6hdr *ic;
 
 		/* Max length: 13 "PROTO=ICMPv6 " */
-		sb_add(m, "PROTO=ICMPv6 ");
+		nf_log_buf_add(m, "PROTO=ICMPv6 ");
 
 		if (fragment)
 			break;
@@ -686,20 +688,22 @@ static void dump_ipv6_packet(struct sbuff *m,
 		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
 		ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
 		if (ic == NULL) {
-			sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
+			nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
+				       skb->len - ptr);
 			return;
 		}
 
 		/* Max length: 18 "TYPE=255 CODE=255 " */
-		sb_add(m, "TYPE=%u CODE=%u ", ic->icmp6_type, ic->icmp6_code);
+		nf_log_buf_add(m, "TYPE=%u CODE=%u ",
+			       ic->icmp6_type, ic->icmp6_code);
 
 		switch (ic->icmp6_type) {
 		case ICMPV6_ECHO_REQUEST:
 		case ICMPV6_ECHO_REPLY:
 			/* Max length: 19 "ID=65535 SEQ=65535 " */
-			sb_add(m, "ID=%u SEQ=%u ",
-				ntohs(ic->icmp6_identifier),
-				ntohs(ic->icmp6_sequence));
+			nf_log_buf_add(m, "ID=%u SEQ=%u ",
+				       ntohs(ic->icmp6_identifier),
+				       ntohs(ic->icmp6_sequence));
 			break;
 		case ICMPV6_MGM_QUERY:
 		case ICMPV6_MGM_REPORT:
@@ -708,28 +712,30 @@ static void dump_ipv6_packet(struct sbuff *m,
 
 		case ICMPV6_PARAMPROB:
 			/* Max length: 17 "POINTER=ffffffff " */
-			sb_add(m, "POINTER=%08x ", ntohl(ic->icmp6_pointer));
+			nf_log_buf_add(m, "POINTER=%08x ",
+				       ntohl(ic->icmp6_pointer));
 			/* Fall through */
 		case ICMPV6_DEST_UNREACH:
 		case ICMPV6_PKT_TOOBIG:
 		case ICMPV6_TIME_EXCEED:
 			/* Max length: 3+maxlen */
 			if (recurse) {
-				sb_add(m, "[");
+				nf_log_buf_add(m, "[");
 				dump_ipv6_packet(m, info, skb,
 					    ptr + sizeof(_icmp6h), 0);
-				sb_add(m, "] ");
+				nf_log_buf_add(m, "] ");
 			}
 
 			/* Max length: 10 "MTU=65535 " */
 			if (ic->icmp6_type == ICMPV6_PKT_TOOBIG)
-				sb_add(m, "MTU=%u ", ntohl(ic->icmp6_mtu));
+				nf_log_buf_add(m, "MTU=%u ",
+					       ntohl(ic->icmp6_mtu));
 		}
 		break;
 	}
 	/* Max length: 10 "PROTO=255 " */
 	default:
-		sb_add(m, "PROTO=%u ", currenthdr);
+		nf_log_buf_add(m, "PROTO=%u ", currenthdr);
 	}
 
 	/* Max length: 15 "UID=4294967295 " */
@@ -738,12 +744,12 @@ static void dump_ipv6_packet(struct sbuff *m,
 
 	/* Max length: 16 "MARK=0xFFFFFFFF " */
 	if (recurse && skb->mark)
-		sb_add(m, "MARK=0x%x ", skb->mark);
+		nf_log_buf_add(m, "MARK=0x%x ", skb->mark);
 }
 
-static void dump_ipv6_mac_header(struct sbuff *m,
-			    const struct nf_loginfo *info,
-			    const struct sk_buff *skb)
+static void dump_ipv6_mac_header(struct nf_log_buf *m,
+				 const struct nf_loginfo *info,
+				 const struct sk_buff *skb)
 {
 	struct net_device *dev = skb->dev;
 	unsigned int logflags = 0;
@@ -756,16 +762,16 @@ static void dump_ipv6_mac_header(struct sbuff *m,
 
 	switch (dev->type) {
 	case ARPHRD_ETHER:
-		sb_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
-		       eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
-		       ntohs(eth_hdr(skb)->h_proto));
+		nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
+			       eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
+			       ntohs(eth_hdr(skb)->h_proto));
 		return;
 	default:
 		break;
 	}
 
 fallback:
-	sb_add(m, "MAC=");
+	nf_log_buf_add(m, "MAC=");
 	if (dev->hard_header_len &&
 	    skb->mac_header != skb->network_header) {
 		const unsigned char *p = skb_mac_header(skb);
@@ -780,20 +786,21 @@ fallback:
 		}
 
 		if (p != NULL) {
-			sb_add(m, "%02x", *p++);
+			nf_log_buf_add(m, "%02x", *p++);
 			for (i = 1; i < len; i++)
-				sb_add(m, ":%02x", *p++);
+				nf_log_buf_add(m, ":%02x", *p++);
 		}
-		sb_add(m, " ");
+		nf_log_buf_add(m, " ");
 
 		if (dev->type == ARPHRD_SIT) {
 			const struct iphdr *iph =
 				(struct iphdr *)skb_mac_header(skb);
-			sb_add(m, "TUNNEL=%pI4->%pI4 ", &iph->saddr,
-			       &iph->daddr);
+			nf_log_buf_add(m, "TUNNEL=%pI4->%pI4 ",
+				       &iph->saddr, &iph->daddr);
 		}
-	} else
-		sb_add(m, " ");
+	} else {
+		nf_log_buf_add(m, " ");
+	}
 }
 
 static void
@@ -806,13 +813,13 @@ ip6t_log_packet(struct net *net,
 		const struct nf_loginfo *loginfo,
 		const char *prefix)
 {
-	struct sbuff *m;
+	struct nf_log_buf *m;
 
 	/* FIXME: Disabled from containers until syslog ns is supported */
 	if (!net_eq(net, &init_net))
 		return;
 
-	m = sb_open();
+	m = nf_log_buf_open();
 
 	if (!loginfo)
 		loginfo = &default_loginfo;
@@ -824,7 +831,7 @@ ip6t_log_packet(struct net *net,
 
 	dump_ipv6_packet(m, loginfo, skb, skb_network_offset(skb), 1);
 
-	sb_close(m);
+	nf_log_buf_close(m);
 }
 #endif