selftests/bpf: Add verifier tests for trusted kfunc args

Make sure verifier rejects the bad cases and ensure the good case keeps
working. The selftests make use of the bpf_kfunc_call_test_ref kfunc
added in the previous patch only for verification.

Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-11-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Kumar Kartikeya Dwivedi 2022-07-21 15:42:42 +02:00 committed by Alexei Starovoitov
parent ef69aa3a98
commit 8dd5e75683

View File

@ -218,6 +218,59 @@
.result = REJECT,
.errstr = "variable ptr_ access var_off=(0x0; 0x7) disallowed",
},
{
"calls: invalid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID",
.insns = {
BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6, 16),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.fixup_kfunc_btf_id = {
{ "bpf_kfunc_call_test_acquire", 3 },
{ "bpf_kfunc_call_test_ref", 8 },
{ "bpf_kfunc_call_test_ref", 10 },
},
.result_unpriv = REJECT,
.result = REJECT,
.errstr = "R1 must be referenced",
},
{
"calls: valid kfunc call: referenced arg needs refcounted PTR_TO_BTF_ID",
.insns = {
BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.fixup_kfunc_btf_id = {
{ "bpf_kfunc_call_test_acquire", 3 },
{ "bpf_kfunc_call_test_ref", 8 },
{ "bpf_kfunc_call_test_release", 10 },
},
.result_unpriv = REJECT,
.result = ACCEPT,
},
{
"calls: basic sanity",
.insns = {