bpf, selftests: Adjust few selftest outcomes wrt unreachable code

In almost all cases from test_verifier that have been changed in here, we've
had an unreachable path with a load from a register which has an invalid
address on purpose. This was basically to make sure that we never walk this
path and to have the verifier complain if it would otherwise. Change it to
match on the right error for unprivileged given we now test these paths
under speculative execution.

There's one case where we match on exact # of insns_processed. Due to the
extra path, this will of course mismatch on unprivileged. Thus, restrict the
test->insn_processed check to privileged-only.

In one other case, we result in a 'pointer comparison prohibited' error. This
is similarly due to verifying an 'invalid' branch where we end up with a value
pointer on one side of the comparison.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/test_verifier.c

@@ -1147,7 +1147,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
 		}
 	}
 
-	if (test->insn_processed) {
+	if (!unpriv && test->insn_processed) {
 		uint32_t insn_processed;
 		char *proc;
 

tools/testing/selftests/bpf/verifier/and.c

@@ -61,6 +61,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R1 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 0
 },

tools/testing/selftests/bpf/verifier/bounds.c

@@ -508,6 +508,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, -1),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT
 },
 {
@@ -528,6 +530,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, -1),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT
 },
 {
@@ -569,6 +573,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 min value is outside of the allowed memory range",
+	.result_unpriv = REJECT,
 	.fixup_map_hash_8b = { 3 },
 	.result = ACCEPT,
 },
@@ -589,6 +595,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 min value is outside of the allowed memory range",
+	.result_unpriv = REJECT,
 	.fixup_map_hash_8b = { 3 },
 	.result = ACCEPT,
 },
@@ -609,6 +617,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 min value is outside of the allowed memory range",
+	.result_unpriv = REJECT,
 	.fixup_map_hash_8b = { 3 },
 	.result = ACCEPT,
 },
@@ -674,6 +684,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 min value is outside of the allowed memory range",
+	.result_unpriv = REJECT,
 	.fixup_map_hash_8b = { 3 },
 	.result = ACCEPT,
 },
@@ -695,6 +707,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 min value is outside of the allowed memory range",
+	.result_unpriv = REJECT,
 	.fixup_map_hash_8b = { 3 },
 	.result = ACCEPT,
 },

tools/testing/selftests/bpf/verifier/dead_code.c

@@ -8,6 +8,8 @@
 	BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 10, -4),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 7,
 },

tools/testing/selftests/bpf/verifier/jmp32.c

@@ -87,6 +87,8 @@
 	BPF_LDX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 },
 {
@@ -150,6 +152,8 @@
 	BPF_LDX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 },
 {
@@ -213,6 +217,8 @@
 	BPF_LDX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 },
 {
@@ -280,6 +286,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -348,6 +356,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -416,6 +426,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -484,6 +496,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -552,6 +566,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -620,6 +636,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -688,6 +706,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },
@@ -756,6 +776,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 2,
 },

tools/testing/selftests/bpf/verifier/jset.c

@@ -82,8 +82,8 @@
 	BPF_EXIT_INSN(),
 	},
 	.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
-	.retval_unpriv = 1,
-	.result_unpriv = ACCEPT,
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.retval = 1,
 	.result = ACCEPT,
 },
@@ -141,7 +141,8 @@
 	BPF_EXIT_INSN(),
 	},
 	.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
-	.result_unpriv = ACCEPT,
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 },
 {
@@ -162,6 +163,7 @@
 	BPF_EXIT_INSN(),
 	},
 	.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
-	.result_unpriv = ACCEPT,
+	.errstr_unpriv = "R9 !read_ok",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 },

tools/testing/selftests/bpf/verifier/unpriv.c

@@ -420,6 +420,8 @@
 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_7, 0),
 	BPF_EXIT_INSN(),
 	},
+	.errstr_unpriv = "R7 invalid mem access 'inv'",
+	.result_unpriv = REJECT,
 	.result = ACCEPT,
 	.retval = 0,
 },

tools/testing/selftests/bpf/verifier/value_ptr_arith.c

@@ -120,7 +120,7 @@
 	.fixup_map_array_48b = { 1 },
 	.result = ACCEPT,
 	.result_unpriv = REJECT,
-	.errstr_unpriv = "R2 tried to add from different maps, paths or scalars",
+	.errstr_unpriv = "R2 pointer comparison prohibited",
 	.retval = 0,
 },
 {
@@ -159,7 +159,8 @@
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
 	// fake-dead code; targeted from branch A to
-	// prevent dead code sanitization
+	// prevent dead code sanitization, rejected
+	// via branch B however
 	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
@@ -167,7 +168,7 @@
 	.fixup_map_array_48b = { 1 },
 	.result = ACCEPT,
 	.result_unpriv = REJECT,
-	.errstr_unpriv = "R2 tried to add from different maps, paths or scalars",
+	.errstr_unpriv = "R0 invalid mem access 'inv'",
 	.retval = 0,
 },
 {