From: John Fastabend <john.fastabend@gmail.com>
Date: Fri, 29 May 2020 10:29:18 -0700
Subject: bpf, selftests: Add a verifier test for assigning 32bit reg states to
64bit ones
Patch-mainline: v5.7
Git-commit: cf66c29bd7534813d2e1971fab71e25fe87c7e0a
References: bsc#1177028
Added a verifier test for assigning 32bit reg states to
64bit where 32bit reg holds a constant value of 0.
Without previous kernel verifier.c fix, the test in
this patch will fail.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/159077335867.6014.2075350327073125374.stgit@john-Precision-5820-Tower
Acked-by: Gary Lin <glin@suse.com>
---
tools/testing/selftests/bpf/verifier/bounds.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
--- a/tools/testing/selftests/bpf/verifier/bounds.c
+++ b/tools/testing/selftests/bpf/verifier/bounds.c
@@ -535,3 +535,25 @@
},
.result = ACCEPT
},
+{
+ "assigning 32bit bounds to 64bit for wA = 0, wB = wA",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_8, BPF_REG_1,
+ offsetof(struct __sk_buff, data_end)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1,
+ offsetof(struct __sk_buff, data)),
+ BPF_MOV32_IMM(BPF_REG_9, 0),
+ BPF_MOV32_REG(BPF_REG_2, BPF_REG_9),
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_7),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_6, BPF_REG_2),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 8),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_8, 1),
+ BPF_LDX_MEM(BPF_W, BPF_REG_5, BPF_REG_6, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
+},