6af2e12374
Ensure that two registers with a map_value loaded from a nested map are considered equivalent for the purpose of state pruning and don't cause the verifier to revisit a pruning point. This uses a rather crude match on the number of insns visited by the verifier, which might change in the future. I've therefore tried to keep the code as "unpruneable" as possible by having the code paths only converge on the second to last instruction. Should you require to adjust the test in the future, reducing the number of processed instructions should always be safe. Increasing them could cause another regression, so proceed with caution. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/CACAyw99hVEJFoiBH_ZGyy=+oO-jyydoz6v1DeKPKs2HVsUH28w@mail.gmail.com Link: https://lore.kernel.org/bpf/20211111161452.86864-1-lmb@cloudflare.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
97 lines
3.1 KiB
C
97 lines
3.1 KiB
C
{
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"map in map access",
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.insns = {
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
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BPF_LD_MAP_FD(BPF_REG_1, 0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
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BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_MOV64_IMM(BPF_REG_0, 0),
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BPF_EXIT_INSN(),
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},
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.fixup_map_in_map = { 3 },
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.result = ACCEPT,
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},
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{
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"map in map state pruning",
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.insns = {
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_6, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, -4),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
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BPF_LD_MAP_FD(BPF_REG_1, 0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
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BPF_EXIT_INSN(),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
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BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 11),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
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BPF_LD_MAP_FD(BPF_REG_1, 0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
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BPF_EXIT_INSN(),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
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BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
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BPF_EXIT_INSN(),
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BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0),
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BPF_EXIT_INSN(),
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},
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.fixup_map_in_map = { 4, 14 },
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.flags = BPF_F_TEST_STATE_FREQ,
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.result = VERBOSE_ACCEPT,
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.errstr = "processed 25 insns",
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.prog_type = BPF_PROG_TYPE_XDP,
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},
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{
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"invalid inner map pointer",
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.insns = {
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
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BPF_LD_MAP_FD(BPF_REG_1, 0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
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BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_MOV64_IMM(BPF_REG_0, 0),
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BPF_EXIT_INSN(),
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},
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.fixup_map_in_map = { 3 },
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.errstr = "R1 pointer arithmetic on map_ptr prohibited",
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.result = REJECT,
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},
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{
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"forgot null checking on the inner map pointer",
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.insns = {
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
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BPF_LD_MAP_FD(BPF_REG_1, 0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_ST_MEM(0, BPF_REG_10, -4, 0),
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BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
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BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
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BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
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BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
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BPF_MOV64_IMM(BPF_REG_0, 0),
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BPF_EXIT_INSN(),
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},
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.fixup_map_in_map = { 3 },
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.errstr = "R1 type=map_value_or_null expected=map_ptr",
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.result = REJECT,
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},
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