From d4ff9ee2dc0bbbdba204e215c8b6bf58f5773994 Mon Sep 17 00:00:00 2001 From: Johan Almbladh Date: Tue, 14 Sep 2021 11:18:37 +0200 Subject: bpf/tests: Add JMP tests with small offsets This patch adds a set of tests for JMP to verify that the JITed jump offset is calculated correctly. We pretend that the verifier has inserted any zero extensions to make the jump-over operations JIT to one instruction each, in order to control the exact JITed jump offset. Signed-off-by: Johan Almbladh Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210914091842.4186267-10-johan.almbladh@anyfinetworks.com --- lib/test_bpf.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) (limited to 'lib/test_bpf.c') diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 0c1c8cccf254..2eb1d0e4aff3 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -10709,6 +10709,77 @@ static struct bpf_test tests[] = { .fill_helper = bpf_fill_jmp32_jsle_reg, .nr_testruns = NR_PATTERN_RUNS, }, + /* Short relative jumps */ + { + "Short relative jump: offset=0", + .u.insns_int = { + BPF_ALU64_IMM(BPF_MOV, R0, 0), + BPF_JMP_IMM(BPF_JEQ, R0, 0, 0), + BPF_EXIT_INSN(), + BPF_ALU32_IMM(BPF_MOV, R0, -1), + }, + INTERNAL | FLAG_NO_DATA | FLAG_VERIFIER_ZEXT, + { }, + { { 0, 0 } }, + }, + { + "Short relative jump: offset=1", + .u.insns_int = { + BPF_ALU64_IMM(BPF_MOV, R0, 0), + BPF_JMP_IMM(BPF_JEQ, R0, 0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_EXIT_INSN(), + BPF_ALU32_IMM(BPF_MOV, R0, -1), + }, + INTERNAL | FLAG_NO_DATA | FLAG_VERIFIER_ZEXT, + { }, + { { 0, 0 } }, + }, + { + "Short relative jump: offset=2", + .u.insns_int = { + BPF_ALU64_IMM(BPF_MOV, R0, 0), + BPF_JMP_IMM(BPF_JEQ, R0, 0, 2), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_EXIT_INSN(), + BPF_ALU32_IMM(BPF_MOV, R0, -1), + }, + INTERNAL | FLAG_NO_DATA | FLAG_VERIFIER_ZEXT, + { }, + { { 0, 0 } }, + }, + { + "Short relative jump: offset=3", + .u.insns_int = { + BPF_ALU64_IMM(BPF_MOV, R0, 0), + BPF_JMP_IMM(BPF_JEQ, R0, 0, 3), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_EXIT_INSN(), + BPF_ALU32_IMM(BPF_MOV, R0, -1), + }, + INTERNAL | FLAG_NO_DATA | FLAG_VERIFIER_ZEXT, + { }, + { { 0, 0 } }, + }, + { + "Short relative jump: offset=4", + .u.insns_int = { + BPF_ALU64_IMM(BPF_MOV, R0, 0), + BPF_JMP_IMM(BPF_JEQ, R0, 0, 4), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_ALU32_IMM(BPF_ADD, R0, 1), + BPF_EXIT_INSN(), + BPF_ALU32_IMM(BPF_MOV, R0, -1), + }, + INTERNAL | FLAG_NO_DATA | FLAG_VERIFIER_ZEXT, + { }, + { { 0, 0 } }, + }, /* Staggered jump sequences, immediate */ { "Staggered jumps: JMP_JA", -- cgit