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, 59 insertions, 0 deletions

diff --git a/include/net/af_ieee802154.h b/include/net/af_ieee802154.h
new file mode 100644
index 000000000..c16be82b9
--- /dev/null
+++ b/include/net/af_ieee802154.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * IEEE 802.15.4 interface for userspace
+ *
+ * Copyright 2007, 2008 Siemens AG
+ *
+ * Written by:
+ * Sergey Lapin <slapin@ossfans.org>
+ * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
+ */
+
+#ifndef _AF_IEEE802154_H
+#define _AF_IEEE802154_H
+
+#include <linux/socket.h> /* for sa_family_t */
+
+enum {
+	IEEE802154_ADDR_NONE = 0x0,
+	/* RESERVED = 0x01, */
+	IEEE802154_ADDR_SHORT = 0x2, /* 16-bit address + PANid */
+	IEEE802154_ADDR_LONG = 0x3, /* 64-bit address + PANid */
+};
+
+/* address length, octets */
+#define IEEE802154_ADDR_LEN	8
+
+struct ieee802154_addr_sa {
+	int addr_type;
+	u16 pan_id;
+	union {
+		u8 hwaddr[IEEE802154_ADDR_LEN];
+		u16 short_addr;
+	};
+};
+
+#define IEEE802154_PANID_BROADCAST	0xffff
+#define IEEE802154_ADDR_BROADCAST	0xffff
+#define IEEE802154_ADDR_UNDEF		0xfffe
+
+struct sockaddr_ieee802154 {
+	sa_family_t family; /* AF_IEEE802154 */
+	struct ieee802154_addr_sa addr;
+};
+
+/* get/setsockopt */
+#define SOL_IEEE802154	0
+
+#define WPAN_WANTACK		0
+#define WPAN_SECURITY		1
+#define WPAN_SECURITY_LEVEL	2
+#define WPAN_WANTLQI		3
+
+#define WPAN_SECURITY_DEFAULT	0
+#define WPAN_SECURITY_OFF	1
+#define WPAN_SECURITY_ON	2
+
+#define WPAN_SECURITY_LEVEL_DEFAULT	(-1)
+
+#endif