Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 289 insertions, 0 deletions

diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
new file mode 100644
index 000000000..b581cb1ee
--- /dev/null
+++ b/net/ipv6/syncookies.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  IPv6 Syncookies implementation for the Linux kernel
+ *
+ *  Authors:
+ *  Glenn Griffin	<ggriffin.kernel@gmail.com>
+ *
+ *  Based on IPv4 implementation by Andi Kleen
+ *  linux/net/ipv4/syncookies.c
+ */
+
+#include <linux/tcp.h>
+#include <linux/random.h>
+#include <linux/siphash.h>
+#include <linux/kernel.h>
+#include <net/secure_seq.h>
+#include <net/ipv6.h>
+#include <net/tcp.h>
+#include <net/tcp_ecn.h>
+
+#define COOKIEBITS 24	/* Upper bits store count */
+#define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1)
+
+static siphash_aligned_key_t syncookie6_secret[2];
+
+/* RFC 2460, Section 8.3:
+ * [ipv6 tcp] MSS must be computed as the maximum packet size minus 60 [..]
+ *
+ * Due to IPV6_MIN_MTU=1280 the lowest possible MSS is 1220, which allows
+ * using higher values than ipv4 tcp syncookies.
+ * The other values are chosen based on ethernet (1500 and 9k MTU), plus
+ * one that accounts for common encap (PPPoe) overhead. Table must be sorted.
+ */
+static __u16 const msstab[] = {
+	1280 - 60, /* IPV6_MIN_MTU - 60 */
+	1480 - 60,
+	1500 - 60,
+	9000 - 60,
+};
+
+static u32 cookie_hash(const struct in6_addr *saddr,
+		       const struct in6_addr *daddr,
+		       __be16 sport, __be16 dport, u32 count, int c)
+{
+	const struct {
+		struct in6_addr saddr;
+		struct in6_addr daddr;
+		u32 count;
+		__be16 sport;
+		__be16 dport;
+	} __aligned(SIPHASH_ALIGNMENT) combined = {
+		.saddr = *saddr,
+		.daddr = *daddr,
+		.count = count,
+		.sport = sport,
+		.dport = dport
+	};
+
+	net_get_random_once(syncookie6_secret, sizeof(syncookie6_secret));
+	return siphash(&combined, offsetofend(typeof(combined), dport),
+		       &syncookie6_secret[c]);
+}
+
+static __u32 secure_tcp_syn_cookie(const struct in6_addr *saddr,
+				   const struct in6_addr *daddr,
+				   __be16 sport, __be16 dport, __u32 sseq,
+				   __u32 data)
+{
+	u32 count = tcp_cookie_time();
+	return (cookie_hash(saddr, daddr, sport, dport, 0, 0) +
+		sseq + (count << COOKIEBITS) +
+		((cookie_hash(saddr, daddr, sport, dport, count, 1) + data)
+		& COOKIEMASK));
+}
+
+static __u32 check_tcp_syn_cookie(__u32 cookie, const struct in6_addr *saddr,
+				  const struct in6_addr *daddr, __be16 sport,
+				  __be16 dport, __u32 sseq)
+{
+	__u32 diff, count = tcp_cookie_time();
+
+	cookie -= cookie_hash(saddr, daddr, sport, dport, 0, 0) + sseq;
+
+	diff = (count - (cookie >> COOKIEBITS)) & ((__u32) -1 >> COOKIEBITS);
+	if (diff >= MAX_SYNCOOKIE_AGE)
+		return (__u32)-1;
+
+	return (cookie -
+		cookie_hash(saddr, daddr, sport, dport, count - diff, 1))
+		& COOKIEMASK;
+}
+
+u32 __cookie_v6_init_sequence(const struct ipv6hdr *iph,
+			      const struct tcphdr *th, __u16 *mssp)
+{
+	int mssind;
+	const __u16 mss = *mssp;
+
+	for (mssind = ARRAY_SIZE(msstab) - 1; mssind ; mssind--)
+		if (mss >= msstab[mssind])
+			break;
+
+	*mssp = msstab[mssind];
+
+	return secure_tcp_syn_cookie(&iph->saddr, &iph->daddr, th->source,
+				     th->dest, ntohl(th->seq), mssind);
+}
+EXPORT_SYMBOL_GPL(__cookie_v6_init_sequence);
+
+__u32 cookie_v6_init_sequence(const struct sk_buff *skb, __u16 *mssp)
+{
+	const struct ipv6hdr *iph = ipv6_hdr(skb);
+	const struct tcphdr *th = tcp_hdr(skb);
+
+	return __cookie_v6_init_sequence(iph, th, mssp);
+}
+
+int __cookie_v6_check(const struct ipv6hdr *iph, const struct tcphdr *th)
+{
+	__u32 cookie = ntohl(th->ack_seq) - 1;
+	__u32 seq = ntohl(th->seq) - 1;
+	__u32 mssind;
+
+	mssind = check_tcp_syn_cookie(cookie, &iph->saddr, &iph->daddr,
+				      th->source, th->dest, seq);
+
+	return mssind < ARRAY_SIZE(msstab) ? msstab[mssind] : 0;
+}
+EXPORT_SYMBOL_GPL(__cookie_v6_check);
+
+static struct request_sock *cookie_tcp_check(struct net *net, struct sock *sk,
+					     struct sk_buff *skb)
+{
+	struct tcp_options_received tcp_opt;
+	u32 tsoff = 0;
+	int mss;
+
+	if (tcp_synq_no_recent_overflow(sk))
+		goto out;
+
+	mss = __cookie_v6_check(ipv6_hdr(skb), tcp_hdr(skb));
+	if (!mss) {
+		__NET_INC_STATS(net, LINUX_MIB_SYNCOOKIESFAILED);
+		goto out;
+	}
+
+	__NET_INC_STATS(net, LINUX_MIB_SYNCOOKIESRECV);
+
+	/* check for timestamp cookie support */
+	memset(&tcp_opt, 0, sizeof(tcp_opt));
+	tcp_parse_options(net, skb, &tcp_opt, 0, NULL);
+
+	if (tcp_opt.saw_tstamp && tcp_opt.rcv_tsecr) {
+		union tcp_seq_and_ts_off st;
+
+		st = secure_tcpv6_seq_and_ts_off(net,
+						 ipv6_hdr(skb)->daddr.s6_addr32,
+						 ipv6_hdr(skb)->saddr.s6_addr32,
+						 tcp_hdr(skb)->dest,
+						 tcp_hdr(skb)->source);
+		tsoff = st.ts_off;
+		tcp_opt.rcv_tsecr -= tsoff;
+	}
+
+	if (!cookie_timestamp_decode(net, &tcp_opt))
+		goto out;
+
+	return cookie_tcp_reqsk_alloc(&tcp6_request_sock_ops, sk, skb,
+				      &tcp_opt, mss, tsoff);
+out:
+	return ERR_PTR(-EINVAL);
+}
+
+struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
+{
+	const struct tcphdr *th = tcp_hdr(skb);
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct inet_request_sock *ireq;
+	struct net *net = sock_net(sk);
+	struct request_sock *req;
+	struct dst_entry *dst;
+	struct sock *ret = sk;
+	__u8 rcv_wscale;
+	int full_space;
+	SKB_DR(reason);
+
+	if (!READ_ONCE(net->ipv4.sysctl_tcp_syncookies) ||
+	    !th->ack || th->rst)
+		goto out;
+
+	if (cookie_bpf_ok(skb)) {
+		req = cookie_bpf_check(sk, skb);
+	} else {
+		req = cookie_tcp_check(net, sk, skb);
+		if (IS_ERR(req))
+			goto out;
+	}
+	if (!req) {
+		SKB_DR_SET(reason, NO_SOCKET);
+		goto out_drop;
+	}
+
+	ireq = inet_rsk(req);
+
+	ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
+	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
+
+	if (security_inet_conn_request(sk, skb, req)) {
+		SKB_DR_SET(reason, SECURITY_HOOK);
+		goto out_free;
+	}
+
+	if (ipv6_opt_accepted(sk, skb, &TCP_SKB_CB(skb)->header.h6) ||
+	    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
+	    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
+		refcount_inc(&skb->users);
+		ireq->pktopts = skb;
+	}
+
+	/* So that link locals have meaning */
+	if (!sk->sk_bound_dev_if &&
+	    ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
+		ireq->ir_iif = tcp_v6_iif(skb);
+
+	tcp_ao_syncookie(sk, skb, req, AF_INET6);
+
+	/*
+	 * We need to lookup the dst_entry to get the correct window size.
+	 * This is taken from tcp_v6_syn_recv_sock.  Somebody please enlighten
+	 * me if there is a preferred way.
+	 */
+	{
+		struct in6_addr *final_p, final;
+		struct flowi6 fl6;
+		memset(&fl6, 0, sizeof(fl6));
+		fl6.flowi6_proto = IPPROTO_TCP;
+		fl6.daddr = ireq->ir_v6_rmt_addr;
+		final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt), &final);
+		fl6.saddr = ireq->ir_v6_loc_addr;
+		fl6.flowi6_oif = ireq->ir_iif;
+		fl6.flowi6_mark = ireq->ir_mark;
+		fl6.fl6_dport = ireq->ir_rmt_port;
+		fl6.fl6_sport = inet_sk(sk)->inet_sport;
+		fl6.flowi6_uid = sk_uid(sk);
+		security_req_classify_flow(req, flowi6_to_flowi_common(&fl6));
+
+		ip6_ecmp_set_mp_hash(net, &fl6, tcp_rsk(req)->txhash);
+
+		dst = ip6_dst_lookup_flow(net, sk, &fl6, final_p);
+		if (IS_ERR(dst)) {
+			SKB_DR_SET(reason, IP_OUTNOROUTES);
+			goto out_free;
+		}
+	}
+
+	req->rsk_window_clamp = READ_ONCE(tp->window_clamp) ? :dst_metric(dst, RTAX_WINDOW);
+	/* limit the window selection if the user enforce a smaller rx buffer */
+	full_space = tcp_full_space(sk);
+	if (sk->sk_userlocks & SOCK_RCVBUF_LOCK &&
+	    (req->rsk_window_clamp > full_space || req->rsk_window_clamp == 0))
+		req->rsk_window_clamp = full_space;
+
+	tcp_select_initial_window(sk, full_space, req->mss,
+				  &req->rsk_rcv_wnd, &req->rsk_window_clamp,
+				  ireq->wscale_ok, &rcv_wscale,
+				  dst_metric(dst, RTAX_INITRWND));
+
+	/* req->syncookie is set true only if ACK is validated
+	 * by BPF kfunc, then, rcv_wscale is already configured.
+	 */
+	if (!req->syncookie)
+		ireq->rcv_wscale = rcv_wscale;
+	ireq->ecn_ok &= cookie_ecn_ok(net, dst);
+	tcp_rsk(req)->accecn_ok = ireq->ecn_ok && cookie_accecn_ok(th);
+
+	ret = tcp_get_cookie_sock(sk, skb, req, dst);
+	if (!ret) {
+		SKB_DR_SET(reason, NO_SOCKET);
+		goto out_drop;
+	}
+out:
+	return ret;
+out_free:
+	reqsk_free(req);
+out_drop:
+	sk_skb_reason_drop(sk, skb, reason);
+	return NULL;
+}