bpf: add test for mixed signed and unsigned bounds checks

These failed due to a bug in verifier bounds handling.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Edward Cree 2017-07-21 00:00:24 +02:00 committed by David S. Miller
parent a150213286
commit b712296a41

View File

@ -5510,6 +5510,58 @@ static struct bpf_test tests[] = {
.errstr = "invalid bpf_context access",
.prog_type = BPF_PROG_TYPE_LWT_IN,
},
{
"bounds checks mixing signed and unsigned, positive bounds",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
BPF_MOV64_IMM(BPF_REG_2, 2),
BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 3),
BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 4, 2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "R0 min value is negative",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"bounds checks mixing signed and unsigned",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
BPF_MOV64_IMM(BPF_REG_2, -1),
BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 3),
BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "R0 min value is negative",
.result = REJECT,
.result_unpriv = REJECT,
},
};
static int probe_filter_length(const struct bpf_insn *fp)