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>

1 files changed, 286 insertions, 0 deletions

diff --git a/include/rdma/ib_pack.h b/include/rdma/ib_pack.h
new file mode 100644
index 000000000..8266fab82
--- /dev/null
+++ b/include/rdma/ib_pack.h
@@ -0,0 +1,286 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
+ */
+
+#ifndef IB_PACK_H
+#define IB_PACK_H
+
+#include <rdma/ib_verbs.h>
+#include <uapi/linux/if_ether.h>
+
+enum {
+	IB_LRH_BYTES		= 8,
+	IB_ETH_BYTES		= 14,
+	IB_VLAN_BYTES		= 4,
+	IB_GRH_BYTES		= 40,
+	IB_IP4_BYTES		= 20,
+	IB_UDP_BYTES		= 8,
+	IB_BTH_BYTES		= 12,
+	IB_DETH_BYTES		= 8,
+	IB_EXT_ATOMICETH_BYTES	= 28,
+	IB_EXT_XRC_BYTES	= 4,
+	IB_ICRC_BYTES		= 4
+};
+
+struct ib_field {
+	size_t struct_offset_bytes;
+	size_t struct_size_bytes;
+	int    offset_words;
+	int    offset_bits;
+	int    size_bits;
+	char  *field_name;
+};
+
+#define RESERVED \
+	.field_name          = "reserved"
+
+/*
+ * This macro cleans up the definitions of constants for BTH opcodes.
+ * It is used to define constants such as IB_OPCODE_UD_SEND_ONLY,
+ * which becomes IB_OPCODE_UD + IB_OPCODE_SEND_ONLY, and this gives
+ * the correct value.
+ *
+ * In short, user code should use the constants defined using the
+ * macro rather than worrying about adding together other constants.
+*/
+#define IB_OPCODE(transport, op) \
+	IB_OPCODE_ ## transport ## _ ## op = \
+		IB_OPCODE_ ## transport + IB_OPCODE_ ## op
+
+enum {
+	/* transport types -- just used to define real constants */
+	IB_OPCODE_RC                                = 0x00,
+	IB_OPCODE_UC                                = 0x20,
+	IB_OPCODE_RD                                = 0x40,
+	IB_OPCODE_UD                                = 0x60,
+	/* per IBTA 1.3 vol 1 Table 38, A10.3.2 */
+	IB_OPCODE_CNP                               = 0x80,
+	/* Manufacturer specific */
+	IB_OPCODE_MSP                               = 0xe0,
+
+	/* operations -- just used to define real constants */
+	IB_OPCODE_SEND_FIRST                        = 0x00,
+	IB_OPCODE_SEND_MIDDLE                       = 0x01,
+	IB_OPCODE_SEND_LAST                         = 0x02,
+	IB_OPCODE_SEND_LAST_WITH_IMMEDIATE          = 0x03,
+	IB_OPCODE_SEND_ONLY                         = 0x04,
+	IB_OPCODE_SEND_ONLY_WITH_IMMEDIATE          = 0x05,
+	IB_OPCODE_RDMA_WRITE_FIRST                  = 0x06,
+	IB_OPCODE_RDMA_WRITE_MIDDLE                 = 0x07,
+	IB_OPCODE_RDMA_WRITE_LAST                   = 0x08,
+	IB_OPCODE_RDMA_WRITE_LAST_WITH_IMMEDIATE    = 0x09,
+	IB_OPCODE_RDMA_WRITE_ONLY                   = 0x0a,
+	IB_OPCODE_RDMA_WRITE_ONLY_WITH_IMMEDIATE    = 0x0b,
+	IB_OPCODE_RDMA_READ_REQUEST                 = 0x0c,
+	IB_OPCODE_RDMA_READ_RESPONSE_FIRST          = 0x0d,
+	IB_OPCODE_RDMA_READ_RESPONSE_MIDDLE         = 0x0e,
+	IB_OPCODE_RDMA_READ_RESPONSE_LAST           = 0x0f,
+	IB_OPCODE_RDMA_READ_RESPONSE_ONLY           = 0x10,
+	IB_OPCODE_ACKNOWLEDGE                       = 0x11,
+	IB_OPCODE_ATOMIC_ACKNOWLEDGE                = 0x12,
+	IB_OPCODE_COMPARE_SWAP                      = 0x13,
+	IB_OPCODE_FETCH_ADD                         = 0x14,
+	/* opcode 0x15 is reserved */
+	IB_OPCODE_SEND_LAST_WITH_INVALIDATE         = 0x16,
+	IB_OPCODE_SEND_ONLY_WITH_INVALIDATE         = 0x17,
+	IB_OPCODE_FLUSH                             = 0x1C,
+	IB_OPCODE_ATOMIC_WRITE                      = 0x1D,
+
+	/* real constants follow -- see comment about above IB_OPCODE()
+	   macro for more details */
+
+	/* RC */
+	IB_OPCODE(RC, SEND_FIRST),
+	IB_OPCODE(RC, SEND_MIDDLE),
+	IB_OPCODE(RC, SEND_LAST),
+	IB_OPCODE(RC, SEND_LAST_WITH_IMMEDIATE),
+	IB_OPCODE(RC, SEND_ONLY),
+	IB_OPCODE(RC, SEND_ONLY_WITH_IMMEDIATE),
+	IB_OPCODE(RC, RDMA_WRITE_FIRST),
+	IB_OPCODE(RC, RDMA_WRITE_MIDDLE),
+	IB_OPCODE(RC, RDMA_WRITE_LAST),
+	IB_OPCODE(RC, RDMA_WRITE_LAST_WITH_IMMEDIATE),
+	IB_OPCODE(RC, RDMA_WRITE_ONLY),
+	IB_OPCODE(RC, RDMA_WRITE_ONLY_WITH_IMMEDIATE),
+	IB_OPCODE(RC, RDMA_READ_REQUEST),
+	IB_OPCODE(RC, RDMA_READ_RESPONSE_FIRST),
+	IB_OPCODE(RC, RDMA_READ_RESPONSE_MIDDLE),
+	IB_OPCODE(RC, RDMA_READ_RESPONSE_LAST),
+	IB_OPCODE(RC, RDMA_READ_RESPONSE_ONLY),
+	IB_OPCODE(RC, ACKNOWLEDGE),
+	IB_OPCODE(RC, ATOMIC_ACKNOWLEDGE),
+	IB_OPCODE(RC, COMPARE_SWAP),
+	IB_OPCODE(RC, FETCH_ADD),
+	IB_OPCODE(RC, SEND_LAST_WITH_INVALIDATE),
+	IB_OPCODE(RC, SEND_ONLY_WITH_INVALIDATE),
+	IB_OPCODE(RC, FLUSH),
+	IB_OPCODE(RC, ATOMIC_WRITE),
+
+	/* UC */
+	IB_OPCODE(UC, SEND_FIRST),
+	IB_OPCODE(UC, SEND_MIDDLE),
+	IB_OPCODE(UC, SEND_LAST),
+	IB_OPCODE(UC, SEND_LAST_WITH_IMMEDIATE),
+	IB_OPCODE(UC, SEND_ONLY),
+	IB_OPCODE(UC, SEND_ONLY_WITH_IMMEDIATE),
+	IB_OPCODE(UC, RDMA_WRITE_FIRST),
+	IB_OPCODE(UC, RDMA_WRITE_MIDDLE),
+	IB_OPCODE(UC, RDMA_WRITE_LAST),
+	IB_OPCODE(UC, RDMA_WRITE_LAST_WITH_IMMEDIATE),
+	IB_OPCODE(UC, RDMA_WRITE_ONLY),
+	IB_OPCODE(UC, RDMA_WRITE_ONLY_WITH_IMMEDIATE),
+
+	/* RD */
+	IB_OPCODE(RD, SEND_FIRST),
+	IB_OPCODE(RD, SEND_MIDDLE),
+	IB_OPCODE(RD, SEND_LAST),
+	IB_OPCODE(RD, SEND_LAST_WITH_IMMEDIATE),
+	IB_OPCODE(RD, SEND_ONLY),
+	IB_OPCODE(RD, SEND_ONLY_WITH_IMMEDIATE),
+	IB_OPCODE(RD, RDMA_WRITE_FIRST),
+	IB_OPCODE(RD, RDMA_WRITE_MIDDLE),
+	IB_OPCODE(RD, RDMA_WRITE_LAST),
+	IB_OPCODE(RD, RDMA_WRITE_LAST_WITH_IMMEDIATE),
+	IB_OPCODE(RD, RDMA_WRITE_ONLY),
+	IB_OPCODE(RD, RDMA_WRITE_ONLY_WITH_IMMEDIATE),
+	IB_OPCODE(RD, RDMA_READ_REQUEST),
+	IB_OPCODE(RD, RDMA_READ_RESPONSE_FIRST),
+	IB_OPCODE(RD, RDMA_READ_RESPONSE_MIDDLE),
+	IB_OPCODE(RD, RDMA_READ_RESPONSE_LAST),
+	IB_OPCODE(RD, RDMA_READ_RESPONSE_ONLY),
+	IB_OPCODE(RD, ACKNOWLEDGE),
+	IB_OPCODE(RD, ATOMIC_ACKNOWLEDGE),
+	IB_OPCODE(RD, COMPARE_SWAP),
+	IB_OPCODE(RD, FETCH_ADD),
+	IB_OPCODE(RD, FLUSH),
+
+	/* UD */
+	IB_OPCODE(UD, SEND_ONLY),
+	IB_OPCODE(UD, SEND_ONLY_WITH_IMMEDIATE)
+};
+
+enum {
+	IB_LNH_RAW        = 0,
+	IB_LNH_IP         = 1,
+	IB_LNH_IBA_LOCAL  = 2,
+	IB_LNH_IBA_GLOBAL = 3
+};
+
+struct ib_unpacked_lrh {
+	u8        virtual_lane;
+	u8        link_version;
+	u8        service_level;
+	u8        link_next_header;
+	__be16    destination_lid;
+	__be16    packet_length;
+	__be16    source_lid;
+};
+
+struct ib_unpacked_grh {
+	u8    	     ip_version;
+	u8    	     traffic_class;
+	__be32 	     flow_label;
+	__be16       payload_length;
+	u8    	     next_header;
+	u8    	     hop_limit;
+	union ib_gid source_gid;
+	union ib_gid destination_gid;
+};
+
+struct ib_unpacked_bth {
+	u8           opcode;
+	u8           solicited_event;
+	u8           mig_req;
+	u8           pad_count;
+	u8           transport_header_version;
+	__be16       pkey;
+	__be32       destination_qpn;
+	u8           ack_req;
+	__be32       psn;
+};
+
+struct ib_unpacked_deth {
+	__be32       qkey;
+	__be32       source_qpn;
+};
+
+struct ib_unpacked_eth {
+	u8	dmac_h[4];
+	u8	dmac_l[2];
+	u8	smac_h[2];
+	u8	smac_l[4];
+	__be16	type;
+};
+
+struct ib_unpacked_ip4 {
+	u8	ver;
+	u8	hdr_len;
+	u8	tos;
+	__be16	tot_len;
+	__be16	id;
+	__be16	frag_off;
+	u8	ttl;
+	u8	protocol;
+	__sum16	check;
+	__be32	saddr;
+	__be32	daddr;
+};
+
+struct ib_unpacked_udp {
+	__be16	sport;
+	__be16	dport;
+	__be16	length;
+	__be16	csum;
+};
+
+struct ib_unpacked_vlan {
+	__be16  tag;
+	__be16  type;
+};
+
+struct ib_ud_header {
+	int                     lrh_present;
+	struct ib_unpacked_lrh  lrh;
+	int			eth_present;
+	struct ib_unpacked_eth	eth;
+	int                     vlan_present;
+	struct ib_unpacked_vlan vlan;
+	int			grh_present;
+	struct ib_unpacked_grh	grh;
+	int			ipv4_present;
+	struct ib_unpacked_ip4	ip4;
+	int			udp_present;
+	struct ib_unpacked_udp	udp;
+	struct ib_unpacked_bth	bth;
+	struct ib_unpacked_deth deth;
+	int			immediate_present;
+	__be32			immediate_data;
+};
+
+void ib_pack(const struct ib_field        *desc,
+	     int                           desc_len,
+	     void                         *structure,
+	     void                         *buf);
+
+void ib_unpack(const struct ib_field        *desc,
+	       int                           desc_len,
+	       void                         *buf,
+	       void                         *structure);
+
+__sum16 ib_ud_ip4_csum(struct ib_ud_header *header);
+
+int ib_ud_header_init(int		    payload_bytes,
+		      int		    lrh_present,
+		      int		    eth_present,
+		      int		    vlan_present,
+		      int		    grh_present,
+		      int		    ip_version,
+		      int		    udp_present,
+		      int		    immediate_present,
+		      struct ib_ud_header *header);
+
+int ib_ud_header_pack(struct ib_ud_header *header,
+		      void                *buf);
+
+#endif /* IB_PACK_H */