selftests/bpf: Test packet range of pointers sharing an idgrafted

Add tests where two packet pointers share an id and tightening one
pointer's umax from its var_off would put it less than their constant
distance from the other's umax: with an index & 0x38 capped at 50, the
base pointer keeps umax 50, so the pointer 8 bytes further on must keep
umax 58, even though its known bits allow at most 56.

These refused a valid program or accepted an out-of-bounds access before
the fix:

- check the advanced copy, load through the base: valid, was refused;
- check the base, load the byte at base + 1 through a copy advanced by
  8: was accepted;
- check base + 4, load 4 bytes at base + 2 through base + 8: reads two
  bytes past the checked range, was accepted;
- the same as the second with data_meta pointers checked against data:
  was accepted.

These pass with and without the fix and cover nearby paths:

- subtract an unknown scalar from a checked pointer and load below it
  (the range is kept across a new id);
- reach a load through two paths whose checks cover 8 and 7 bytes after
  the loaded pointer; the second path must not be pruned by the first;
- spill a copy of a pointer, check the pointer, fill the copy and load
  one byte past the checked range: the load is refused, and the copy
  has the range of the check.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

4 files changed, 371 insertions, 0 deletions

diff --git a/include/net/phonet/gprs.h b/include/net/phonet/gprs.h
new file mode 100644
index 000000000..6b7f57b2f
--- /dev/null
+++ b/include/net/phonet/gprs.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * File: pep_gprs.h
+ *
+ * GPRS over Phonet pipe end point socket
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Author: Rémi Denis-Courmont
+ */
+
+#ifndef NET_PHONET_GPRS_H
+#define NET_PHONET_GPRS_H
+
+struct sock;
+struct sk_buff;
+
+int pep_writeable(struct sock *sk);
+int pep_write(struct sock *sk, struct sk_buff *skb);
+struct sk_buff *pep_read(struct sock *sk);
+
+int gprs_attach(struct sock *sk);
+void gprs_detach(struct sock *sk);
+
+#endif
diff --git a/include/net/phonet/pep.h b/include/net/phonet/pep.h
new file mode 100644
index 000000000..645dddf5c
--- /dev/null
+++ b/include/net/phonet/pep.h
@@ -0,0 +1,159 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * File: pep.h
+ *
+ * Phonet Pipe End Point sockets definitions
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ */
+
+#ifndef NET_PHONET_PEP_H
+#define NET_PHONET_PEP_H
+
+#include <linux/skbuff.h>
+#include <net/phonet/phonet.h>
+
+struct pep_sock {
+	struct pn_sock		pn_sk;
+
+	/* XXX: union-ify listening vs connected stuff ? */
+	/* Listening socket stuff: */
+	struct hlist_head	hlist;
+
+	/* Connected socket stuff: */
+	struct sock		*listener;
+	struct sk_buff_head	ctrlreq_queue;
+#define PNPIPE_CTRLREQ_MAX	10
+	atomic_t		tx_credits;
+	int			ifindex;
+	u16			peer_type;	/* peer type/subtype */
+	u8			pipe_handle;
+
+	u8			rx_credits;
+	u8			rx_fc;	/* RX flow control */
+	u8			tx_fc;	/* TX flow control */
+	u8			init_enable;	/* auto-enable at creation */
+	u8			aligned;
+};
+
+static inline struct pep_sock *pep_sk(struct sock *sk)
+{
+	return (struct pep_sock *)sk;
+}
+
+extern const struct proto_ops phonet_stream_ops;
+
+/* Pipe protocol definitions */
+struct pnpipehdr {
+	u8			utid; /* transaction ID */
+	u8			message_id;
+	u8			pipe_handle;
+	union {
+		u8		state_after_connect;	/* connect request */
+		u8		state_after_reset;	/* reset request */
+		u8		error_code;		/* any response */
+		u8		pep_type;		/* status indication */
+		u8		data0;			/* anything else */
+	};
+	u8			data[];
+};
+#define other_pep_type		data[0]
+
+static inline struct pnpipehdr *pnp_hdr(struct sk_buff *skb)
+{
+	return (struct pnpipehdr *)skb_transport_header(skb);
+}
+
+#define MAX_PNPIPE_HEADER (MAX_PHONET_HEADER + 4)
+
+enum {
+	PNS_PIPE_CREATE_REQ = 0x00,
+	PNS_PIPE_CREATE_RESP,
+	PNS_PIPE_REMOVE_REQ,
+	PNS_PIPE_REMOVE_RESP,
+
+	PNS_PIPE_DATA = 0x20,
+	PNS_PIPE_ALIGNED_DATA,
+
+	PNS_PEP_CONNECT_REQ = 0x40,
+	PNS_PEP_CONNECT_RESP,
+	PNS_PEP_DISCONNECT_REQ,
+	PNS_PEP_DISCONNECT_RESP,
+	PNS_PEP_RESET_REQ,
+	PNS_PEP_RESET_RESP,
+	PNS_PEP_ENABLE_REQ,
+	PNS_PEP_ENABLE_RESP,
+	PNS_PEP_CTRL_REQ,
+	PNS_PEP_CTRL_RESP,
+	PNS_PEP_DISABLE_REQ = 0x4C,
+	PNS_PEP_DISABLE_RESP,
+
+	PNS_PEP_STATUS_IND = 0x60,
+	PNS_PIPE_CREATED_IND,
+	PNS_PIPE_RESET_IND = 0x63,
+	PNS_PIPE_ENABLED_IND,
+	PNS_PIPE_REDIRECTED_IND,
+	PNS_PIPE_DISABLED_IND = 0x66,
+};
+
+#define PN_PIPE_INVALID_HANDLE	0xff
+#define PN_PEP_TYPE_COMMON	0x00
+
+/* Phonet pipe status indication */
+enum {
+	PN_PEP_IND_FLOW_CONTROL,
+	PN_PEP_IND_ID_MCFC_GRANT_CREDITS,
+};
+
+/* Phonet pipe error codes */
+enum {
+	PN_PIPE_NO_ERROR,
+	PN_PIPE_ERR_INVALID_PARAM,
+	PN_PIPE_ERR_INVALID_HANDLE,
+	PN_PIPE_ERR_INVALID_CTRL_ID,
+	PN_PIPE_ERR_NOT_ALLOWED,
+	PN_PIPE_ERR_PEP_IN_USE,
+	PN_PIPE_ERR_OVERLOAD,
+	PN_PIPE_ERR_DEV_DISCONNECTED,
+	PN_PIPE_ERR_TIMEOUT,
+	PN_PIPE_ERR_ALL_PIPES_IN_USE,
+	PN_PIPE_ERR_GENERAL,
+	PN_PIPE_ERR_NOT_SUPPORTED,
+};
+
+/* Phonet pipe states */
+enum {
+	PN_PIPE_DISABLE,
+	PN_PIPE_ENABLE,
+};
+
+/* Phonet pipe sub-block types */
+enum {
+	PN_PIPE_SB_CREATE_REQ_PEP_SUB_TYPE,
+	PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE,
+	PN_PIPE_SB_REDIRECT_REQ_PEP_SUB_TYPE,
+	PN_PIPE_SB_NEGOTIATED_FC,
+	PN_PIPE_SB_REQUIRED_FC_TX,
+	PN_PIPE_SB_PREFERRED_FC_RX,
+	PN_PIPE_SB_ALIGNED_DATA,
+};
+
+/* Phonet pipe flow control models */
+enum {
+	PN_NO_FLOW_CONTROL,
+	PN_LEGACY_FLOW_CONTROL,
+	PN_ONE_CREDIT_FLOW_CONTROL,
+	PN_MULTI_CREDIT_FLOW_CONTROL,
+	PN_MAX_FLOW_CONTROL,
+};
+
+#define pn_flow_safe(fc) ((fc) >> 1)
+
+/* Phonet pipe flow control states */
+enum {
+	PEP_IND_EMPTY,
+	PEP_IND_BUSY,
+	PEP_IND_READY,
+};
+
+#endif
diff --git a/include/net/phonet/phonet.h b/include/net/phonet/phonet.h
new file mode 100644
index 000000000..cf5ecae4a
--- /dev/null
+++ b/include/net/phonet/phonet.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * File: af_phonet.h
+ *
+ * Phonet sockets kernel definitions
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ */
+
+#ifndef AF_PHONET_H
+#define AF_PHONET_H
+
+#include <linux/phonet.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+
+/*
+ * The lower layers may not require more space, ever. Make sure it's
+ * enough.
+ */
+#define MAX_PHONET_HEADER	(8 + MAX_HEADER)
+
+/*
+ * Every Phonet* socket has this structure first in its
+ * protocol-specific structure under name c.
+ */
+struct pn_sock {
+	struct sock	sk;
+	u16		sobject;
+	u16		dobject;
+	u8		resource;
+};
+
+static inline struct pn_sock *pn_sk(struct sock *sk)
+{
+	return (struct pn_sock *)sk;
+}
+
+extern const struct proto_ops phonet_dgram_ops;
+
+void pn_sock_init(void);
+struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *sa);
+void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb);
+void phonet_get_local_port_range(int *min, int *max);
+int pn_sock_hash(struct sock *sk);
+void pn_sock_unhash(struct sock *sk);
+int pn_sock_get_port(struct sock *sk, unsigned short sport);
+
+struct sock *pn_find_sock_by_res(struct net *net, u8 res);
+int pn_sock_bind_res(struct sock *sock, u8 res);
+int pn_sock_unbind_res(struct sock *sk, u8 res);
+void pn_sock_unbind_all_res(struct sock *sk);
+
+int pn_skb_send(struct sock *sk, struct sk_buff *skb,
+		const struct sockaddr_pn *target);
+
+static inline struct phonethdr *pn_hdr(struct sk_buff *skb)
+{
+	return (struct phonethdr *)skb_network_header(skb);
+}
+
+static inline struct phonetmsg *pn_msg(struct sk_buff *skb)
+{
+	return (struct phonetmsg *)skb_transport_header(skb);
+}
+
+/*
+ * Get the other party's sockaddr from received skb. The skb begins
+ * with a Phonet header.
+ */
+static inline
+void pn_skb_get_src_sockaddr(struct sk_buff *skb, struct sockaddr_pn *sa)
+{
+	struct phonethdr *ph = pn_hdr(skb);
+	u16 obj = pn_object(ph->pn_sdev, ph->pn_sobj);
+
+	sa->spn_family = AF_PHONET;
+	pn_sockaddr_set_object(sa, obj);
+	pn_sockaddr_set_resource(sa, ph->pn_res);
+	memset(sa->spn_zero, 0, sizeof(sa->spn_zero));
+}
+
+static inline
+void pn_skb_get_dst_sockaddr(struct sk_buff *skb, struct sockaddr_pn *sa)
+{
+	struct phonethdr *ph = pn_hdr(skb);
+	u16 obj = pn_object(ph->pn_rdev, ph->pn_robj);
+
+	sa->spn_family = AF_PHONET;
+	pn_sockaddr_set_object(sa, obj);
+	pn_sockaddr_set_resource(sa, ph->pn_res);
+	memset(sa->spn_zero, 0, sizeof(sa->spn_zero));
+}
+
+/* Protocols in Phonet protocol family. */
+struct phonet_protocol {
+	const struct proto_ops	*ops;
+	struct proto		*prot;
+	int			sock_type;
+};
+
+int phonet_proto_register(unsigned int protocol,
+		const struct phonet_protocol *pp);
+void phonet_proto_unregister(unsigned int protocol,
+		const struct phonet_protocol *pp);
+
+int phonet_sysctl_init(void);
+void phonet_sysctl_exit(void);
+int isi_register(void);
+void isi_unregister(void);
+
+static inline bool sk_is_phonet(struct sock *sk)
+{
+	return sk->sk_family == PF_PHONET;
+}
+
+static inline int phonet_sk_ioctl(struct sock *sk, unsigned int cmd,
+				  void __user *arg)
+{
+	int karg;
+
+	switch (cmd) {
+	case SIOCPNADDRESOURCE:
+	case SIOCPNDELRESOURCE:
+		if (get_user(karg, (int __user *)arg))
+			return -EFAULT;
+
+		return sk->sk_prot->ioctl(sk, cmd, &karg);
+	}
+	/* A positive return value means that the ioctl was not processed */
+	return 1;
+}
+#endif
diff --git a/include/net/phonet/pn_dev.h b/include/net/phonet/pn_dev.h
new file mode 100644
index 000000000..37a3e8353
--- /dev/null
+++ b/include/net/phonet/pn_dev.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * File: pn_dev.h
+ *
+ * Phonet network device
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ */
+
+#ifndef PN_DEV_H
+#define PN_DEV_H
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+struct net;
+
+struct phonet_device_list {
+	struct list_head list;
+	spinlock_t lock;
+};
+
+struct phonet_device_list *phonet_device_list(struct net *net);
+
+struct phonet_device {
+	struct list_head list;
+	struct net_device *netdev;
+	DECLARE_BITMAP(addrs, 64);
+	struct rcu_head	rcu;
+};
+
+int phonet_device_init(void);
+void phonet_device_exit(void);
+int phonet_netlink_register(void);
+struct net_device *phonet_device_get(struct net *net);
+
+int phonet_address_add(struct net_device *dev, u8 addr);
+int phonet_address_del(struct net_device *dev, u8 addr);
+u8 phonet_address_get(struct net_device *dev, u8 addr);
+int phonet_address_lookup(struct net *net, u8 addr);
+void phonet_address_notify(struct net *net, int event, u32 ifindex, u8 addr);
+
+int phonet_route_add(struct net_device *dev, u8 daddr);
+int phonet_route_del(struct net_device *dev, u8 daddr);
+void rtm_phonet_notify(struct net *net, int event, u32 ifindex, u8 dst);
+struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr);
+struct net_device *phonet_route_output(struct net *net, u8 daddr);
+
+#define PN_NO_ADDR	0xff
+
+extern const struct seq_operations pn_sock_seq_ops;
+extern const struct seq_operations pn_res_seq_ops;
+
+#endif