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| author | Daniel Borkmann <daniel@iogearbox.net> | 2021-12-16 00:48:54 +0100 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2021-12-16 19:46:06 +0100 |
| commit | b1a7288dedc6caf9023f2676b4f5ed34cf0d4029 (patch) | |
| tree | f8813e16d20cfbef5eaa561986390472f11f0d3d /tools | |
| parent | bpf: Make 32->64 bounds propagation slightly more robust (diff) | |
| download | linux-b1a7288dedc6caf9023f2676b4f5ed34cf0d4029.tar.xz linux-b1a7288dedc6caf9023f2676b4f5ed34cf0d4029.zip | |
bpf, selftests: Add test case trying to taint map value pointer
Add a test case which tries to taint map value pointer arithmetic into a
unknown scalar with subsequent export through the map.
Before fix:
# ./test_verifier 1186
#1186/u map access: trying to leak tained dst reg FAIL
Unexpected success to load!
verification time 24 usec
stack depth 8
processed 15 insns (limit 1000000) max_states_per_insn 0 total_states 1 peak_states 1 mark_read 1
#1186/p map access: trying to leak tained dst reg FAIL
Unexpected success to load!
verification time 8 usec
stack depth 8
processed 15 insns (limit 1000000) max_states_per_insn 0 total_states 1 peak_states 1 mark_read 1
Summary: 0 PASSED, 0 SKIPPED, 2 FAILED
After fix:
# ./test_verifier 1186
#1186/u map access: trying to leak tained dst reg OK
#1186/p map access: trying to leak tained dst reg OK
Summary: 2 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/value_ptr_arith.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c index 2debba4e8a3a..4d347bc53aa2 100644 --- a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c +++ b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c @@ -1078,6 +1078,29 @@ .errstr_unpriv = "R0 pointer -= pointer prohibited", }, { + "map access: trying to leak tained dst reg", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 0), + 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_JNE, BPF_REG_0, 0, 1), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_0), + BPF_MOV32_IMM(BPF_REG_1, 0xFFFFFFFF), + BPF_MOV32_REG(BPF_REG_1, BPF_REG_1), + BPF_ALU64_REG(BPF_SUB, BPF_REG_2, BPF_REG_1), + BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .fixup_map_array_48b = { 4 }, + .result = REJECT, + .errstr = "math between map_value pointer and 4294967295 is not allowed", +}, +{ "32bit pkt_ptr -= scalar", .insns = { BPF_LDX_MEM(BPF_W, BPF_REG_8, BPF_REG_1, |