From 4bbbf164f1a5e970543dcdb7a396fc1cf477725b Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Thu, 3 Oct 2019 01:45:12 +0200 Subject: [PATCH] bpf: Add loop test case with 32 bit reg comparison against 0 Add a loop test with 32 bit register against 0 immediate: # ./test_verifier 631 #631/p taken loop with back jump to 1st insn, 2 OK Disassembly: [...] 1b: test %edi,%edi 1d: jne 0x0000000000000014 [...] Pretty much similar to prior "taken loop with back jump to 1st insn" test case just as jmp32 variant. Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Acked-by: Song Liu --- tools/testing/selftests/bpf/verifier/loops1.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/tools/testing/selftests/bpf/verifier/loops1.c b/tools/testing/selftests/bpf/verifier/loops1.c index 1fc4e61e9f9f..1af37187dc12 100644 --- a/tools/testing/selftests/bpf/verifier/loops1.c +++ b/tools/testing/selftests/bpf/verifier/loops1.c @@ -187,3 +187,20 @@ .prog_type = BPF_PROG_TYPE_XDP, .retval = 55, }, +{ + "taken loop with back jump to 1st insn, 2", + .insns = { + BPF_MOV64_IMM(BPF_REG_1, 10), + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 1), + BPF_EXIT_INSN(), + BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_1), + BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 1), + BPF_JMP32_IMM(BPF_JNE, BPF_REG_1, 0, -3), + BPF_MOV64_REG(BPF_REG_0, BPF_REG_2), + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_XDP, + .retval = 55, +}, -- 2.30.2