From f1a8b8e3d98b0b3d1d88d119f52cc85d05ab3189 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 21 Nov 2017 11:23:40 -0800 Subject: [PATCH] bpf: change bpf_probe_write_user to bpf_trace_printk in test_verifier There are four tests in test_verifier using bpf_probe_write_user helper. These four tests will emit the following kernel messages [ 12.974753] test_verifier[220] is installing a program with bpf_probe_write_user helper that may corrupt user memory! [ 12.979285] test_verifier[220] is installing a program with bpf_probe_write_user helper that may corrupt user memory! ...... This may confuse certain users. This patch replaces bpf_probe_write_user with bpf_trace_printk. The test_verifier already uses bpf_trace_printk earlier in the test and a trace_printk warning message has been printed. So this patch does not emit any more kernel messages. Fixes: b6ff63911232 ("bpf: fix and add test cases for ARG_CONST_SIZE_OR_ZERO semantics change") Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann --- tools/testing/selftests/bpf/test_verifier.c | 39 +++++++++------------ 1 file changed, 16 insertions(+), 23 deletions(-) diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index bf092b83e453..2a5267bef160 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -4377,11 +4377,10 @@ static struct bpf_test tests[] = { BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4), - BPF_MOV64_IMM(BPF_REG_1, 0), - BPF_MOV64_REG(BPF_REG_2, BPF_REG_0), - BPF_MOV64_IMM(BPF_REG_3, 0), - BPF_EMIT_CALL(BPF_FUNC_probe_write_user), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_EMIT_CALL(BPF_FUNC_trace_printk), BPF_EXIT_INSN(), }, .fixup_map2 = { 3 }, @@ -4481,14 +4480,12 @@ static struct bpf_test tests[] = { BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4), BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, offsetof(struct test_val, foo)), - BPF_MOV64_REG(BPF_REG_2, BPF_REG_1), - BPF_MOV64_IMM(BPF_REG_1, 0), - BPF_MOV64_IMM(BPF_REG_3, 0), - BPF_EMIT_CALL(BPF_FUNC_probe_write_user), + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_EMIT_CALL(BPF_FUNC_trace_printk), BPF_EXIT_INSN(), }, .fixup_map2 = { 3 }, @@ -4618,18 +4615,16 @@ static struct bpf_test tests[] = { BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5), BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), BPF_MOV64_IMM(BPF_REG_3, 0), BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3), - BPF_MOV64_REG(BPF_REG_2, BPF_REG_1), - BPF_MOV64_IMM(BPF_REG_1, 0), - BPF_MOV64_IMM(BPF_REG_3, 0), - BPF_EMIT_CALL(BPF_FUNC_probe_write_user), + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_EMIT_CALL(BPF_FUNC_trace_printk), BPF_EXIT_INSN(), }, .fixup_map2 = { 3 }, - .errstr = "R2 min value is outside of the array range", + .errstr = "R1 min value is outside of the array range", .result = REJECT, .prog_type = BPF_PROG_TYPE_TRACEPOINT, }, @@ -4760,20 +4755,18 @@ static struct bpf_test tests[] = { BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0), BPF_LD_MAP_FD(BPF_REG_1, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), - BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6), BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0), BPF_JMP_IMM(BPF_JGT, BPF_REG_3, - offsetof(struct test_val, foo), 4), + offsetof(struct test_val, foo), 3), BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3), - BPF_MOV64_REG(BPF_REG_2, BPF_REG_1), - BPF_MOV64_IMM(BPF_REG_1, 0), - BPF_MOV64_IMM(BPF_REG_3, 0), - BPF_EMIT_CALL(BPF_FUNC_probe_write_user), + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_EMIT_CALL(BPF_FUNC_trace_printk), BPF_EXIT_INSN(), }, .fixup_map2 = { 3 }, - .errstr = "R2 min value is outside of the array range", + .errstr = "R1 min value is outside of the array range", .result = REJECT, .prog_type = BPF_PROG_TYPE_TRACEPOINT, }, -- 2.30.2