bpf, selftests: Add a verifier test for assigning 32bit reg states to 64bit ones

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
This commit is contained in:
John Fastabend 2020-05-29 10:29:18 -07:00 committed by Alexei Starovoitov
parent e3effcdfe0
commit cf66c29bd7

View file

@ -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,
},