diff options
| author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2019-06-13 00:21:39 +0530 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2019-06-13 23:07:00 +0200 |
| commit | 3e0682695199bad51dd898fe064d1564637ff77a (patch) | |
| tree | a63884494c3ac859560d7056cb1def9095b1c4fa | |
| parent | 0e265747491cb182429adfbef7d002164566f25c (diff) | |
bpf: fix div64 overflow tests to properly detect errors
If the result of the division is LLONG_MIN, current tests do not detect
the error since the return value is truncated to a 32-bit value and ends
up being 0.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/div_overflow.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/tools/testing/selftests/bpf/verifier/div_overflow.c b/tools/testing/selftests/bpf/verifier/div_overflow.c index bd3f38dbe796..acab4f00819f 100644 --- a/tools/testing/selftests/bpf/verifier/div_overflow.c +++ b/tools/testing/selftests/bpf/verifier/div_overflow.c @@ -29,8 +29,11 @@ "DIV64 overflow, check 1", .insns = { BPF_MOV64_IMM(BPF_REG_1, -1), - BPF_LD_IMM64(BPF_REG_0, LLONG_MIN), - BPF_ALU64_REG(BPF_DIV, BPF_REG_0, BPF_REG_1), + BPF_LD_IMM64(BPF_REG_2, LLONG_MIN), + BPF_ALU64_REG(BPF_DIV, BPF_REG_2, BPF_REG_1), + BPF_MOV32_IMM(BPF_REG_0, 0), + BPF_JMP_REG(BPF_JEQ, BPF_REG_0, BPF_REG_2, 1), + BPF_MOV32_IMM(BPF_REG_0, 1), BPF_EXIT_INSN(), }, .prog_type = BPF_PROG_TYPE_SCHED_CLS, @@ -40,8 +43,11 @@ { "DIV64 overflow, check 2", .insns = { - BPF_LD_IMM64(BPF_REG_0, LLONG_MIN), - BPF_ALU64_IMM(BPF_DIV, BPF_REG_0, -1), + BPF_LD_IMM64(BPF_REG_1, LLONG_MIN), + BPF_ALU64_IMM(BPF_DIV, BPF_REG_1, -1), + BPF_MOV32_IMM(BPF_REG_0, 0), + BPF_JMP_REG(BPF_JEQ, BPF_REG_0, BPF_REG_1, 1), + BPF_MOV32_IMM(BPF_REG_0, 1), BPF_EXIT_INSN(), }, .prog_type = BPF_PROG_TYPE_SCHED_CLS, |