Thread (2 messages) 2 messages, 2 authors, 2021-12-08

[PATCH bpf] bpf: Add selftests to cover packet access corner cases

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STALE1774d LANDED

From: Maxim Mikityanskiy <hidden>
Date: 2021-12-07 08:15:34
Also in: bpf
Subsystem: bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest, xdp (express data path) · Maintainers: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Shuah Khan, Linus Torvalds, David S. Miller, Jakub Kicinski, Jesper Dangaard Brouer, John Fastabend

Landed in mainline as b560b21f71eb on 2021-12-08.

This commit adds BPF verifier selftests that cover all corner cases by
packet boundary checks. Specifically, 8-byte packet reads are tested at
the beginning of data and at the beginning of data_meta, using all kinds
of boundary checks (all comparison operators: <, >, <=, >=; both
permutations of operands: data + length compared to end, end compared to
data + length). For each case there are three tests:

1. Length is just enough for an 8-byte read. Length is either 7 or 8,
   depending on the comparison.

2. Length is increased by 1 - should still pass the verifier. These
   cases are useful, because they failed before commit 2fa7d94afc1a
   ("bpf: Fix the off-by-two error in range markings").

3. Length is decreased by 1 - should be rejected by the verifier.

Some existing tests are just renamed to avoid duplication.

Signed-off-by: Maxim Mikityanskiy <redacted>
---
 .../bpf/verifier/xdp_direct_packet_access.c   | 600 +++++++++++++++++-
 1 file changed, 584 insertions(+), 16 deletions(-)
diff --git a/tools/testing/selftests/bpf/verifier/xdp_direct_packet_access.c b/tools/testing/selftests/bpf/verifier/xdp_direct_packet_access.c
index de172a5b8754..b4ec228eb95d 100644
--- a/tools/testing/selftests/bpf/verifier/xdp_direct_packet_access.c
+++ b/tools/testing/selftests/bpf/verifier/xdp_direct_packet_access.c
@@ -35,7 +35,7 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 },
 {
-	"XDP pkt read, pkt_data' > pkt_end, good access",
+	"XDP pkt read, pkt_data' > pkt_end, corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -87,6 +87,41 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_data' > pkt_end, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data' > pkt_end, corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_end > pkt_data', good access",
 	.insns = {
@@ -106,7 +141,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_end > pkt_data', bad access 1",
+	"XDP pkt read, pkt_end > pkt_data', corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -142,6 +177,42 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_end > pkt_data', corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_end > pkt_data', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_data' < pkt_end, good access",
 	.insns = {
@@ -161,7 +232,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data' < pkt_end, bad access 1",
+	"XDP pkt read, pkt_data' < pkt_end, corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -198,7 +269,43 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_end < pkt_data', good access",
+	"XDP pkt read, pkt_data' < pkt_end, corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data' < pkt_end, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_end < pkt_data', corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -250,6 +357,41 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_end < pkt_data', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_end < pkt_data', corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_data' >= pkt_end, good access",
 	.insns = {
@@ -268,7 +410,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data' >= pkt_end, bad access 1",
+	"XDP pkt read, pkt_data' >= pkt_end, corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -304,7 +446,41 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_end >= pkt_data', good access",
+	"XDP pkt read, pkt_data' >= pkt_end, corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data' >= pkt_end, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_end >= pkt_data', corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -359,7 +535,44 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data' <= pkt_end, good access",
+	"XDP pkt read, pkt_end >= pkt_data', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_end >= pkt_data', corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data' <= pkt_end, corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -413,6 +626,43 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_data' <= pkt_end, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data' <= pkt_end, corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_end <= pkt_data', good access",
 	.insns = {
@@ -431,7 +681,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_end <= pkt_data', bad access 1",
+	"XDP pkt read, pkt_end <= pkt_data', corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
 	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
@@ -467,7 +717,41 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_meta' > pkt_data, good access",
+	"XDP pkt read, pkt_end <= pkt_data', corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_end <= pkt_data', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+		    offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_meta' > pkt_data, corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -519,6 +803,41 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_meta' > pkt_data, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_meta' > pkt_data, corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_data > pkt_meta', good access",
 	.insns = {
@@ -538,7 +857,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data > pkt_meta', bad access 1",
+	"XDP pkt read, pkt_data > pkt_meta', corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -574,6 +893,42 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_data > pkt_meta', corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data > pkt_meta', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_meta' < pkt_data, good access",
 	.insns = {
@@ -593,7 +948,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_meta' < pkt_data, bad access 1",
+	"XDP pkt read, pkt_meta' < pkt_data, corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -630,7 +985,43 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data < pkt_meta', good access",
+	"XDP pkt read, pkt_meta' < pkt_data, corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_meta' < pkt_data, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data < pkt_meta', corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -682,6 +1073,41 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_data < pkt_meta', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data < pkt_meta', corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_meta' >= pkt_data, good access",
 	.insns = {
@@ -700,7 +1126,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_meta' >= pkt_data, bad access 1",
+	"XDP pkt read, pkt_meta' >= pkt_data, corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -736,7 +1162,41 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data >= pkt_meta', good access",
+	"XDP pkt read, pkt_meta' >= pkt_data, corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_meta' >= pkt_data, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data >= pkt_meta', corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -791,7 +1251,44 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_meta' <= pkt_data, good access",
+	"XDP pkt read, pkt_data >= pkt_meta', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data >= pkt_meta', corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_meta' <= pkt_data, corner case, good access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -845,6 +1342,43 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_meta' <= pkt_data, corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 9),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -9),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_meta' <= pkt_data, corner case -1, bad access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_1, BPF_REG_3, 1),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "R1 offset is outside of the packet",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
 {
 	"XDP pkt read, pkt_data <= pkt_meta', good access",
 	.insns = {
@@ -863,7 +1397,7 @@
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
-	"XDP pkt read, pkt_data <= pkt_meta', bad access 1",
+	"XDP pkt read, pkt_data <= pkt_meta', corner case -1, bad access",
 	.insns = {
 	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
 		    offsetof(struct xdp_md, data_meta)),
@@ -898,3 +1432,37 @@
 	.prog_type = BPF_PROG_TYPE_XDP,
 	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
+{
+	"XDP pkt read, pkt_data <= pkt_meta', corner case, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -7),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
+{
+	"XDP pkt read, pkt_data <= pkt_meta', corner case +1, good access",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+		    offsetof(struct xdp_md, data_meta)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+	BPF_JMP_REG(BPF_JLE, BPF_REG_3, BPF_REG_1, 1),
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},
-- 
2.30.2
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