From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joe Stringer Subject: [RFC bpf-next 02/11] bpf: Simplify ptr_min_max_vals adjustment Date: Wed, 9 May 2018 14:07:00 -0700 Message-ID: <20180509210709.7201-3-joe@wand.net.nz> References: <20180509210709.7201-1-joe@wand.net.nz> Cc: netdev@vger.kernel.org, ast@kernel.org, john.fastabend@gmail.com, kafai@fb.com To: daniel@iogearbox.net Return-path: Received: from mail-ot0-f196.google.com ([74.125.82.196]:44531 "EHLO mail-ot0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964849AbeEIVHZ (ORCPT ); Wed, 9 May 2018 17:07:25 -0400 Received: by mail-ot0-f196.google.com with SMTP id g7-v6so41784777otj.11 for ; Wed, 09 May 2018 14:07:25 -0700 (PDT) In-Reply-To: <20180509210709.7201-1-joe@wand.net.nz> Sender: netdev-owner@vger.kernel.org List-ID: An upcoming commit will add another two pointer types that need very similar behaviour, so generalise this function now. Signed-off-by: Joe Stringer --- kernel/bpf/verifier.c | 22 ++++++++++------------ tools/testing/selftests/bpf/test_verifier.c | 14 +++++++------- 2 files changed, 17 insertions(+), 19 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index f40e089c3893..a32b560072d7 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2602,20 +2602,18 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, return -EACCES; } - if (ptr_reg->type == PTR_TO_MAP_VALUE_OR_NULL) { - verbose(env, "R%d pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL prohibited, null-check it first\n", - dst); - return -EACCES; - } - if (ptr_reg->type == CONST_PTR_TO_MAP) { - verbose(env, "R%d pointer arithmetic on CONST_PTR_TO_MAP prohibited\n", - dst); + switch (ptr_reg->type) { + case PTR_TO_MAP_VALUE_OR_NULL: + verbose(env, "R%d pointer arithmetic on %s prohibited, null-check it first\n", + dst, reg_type_str[ptr_reg->type]); return -EACCES; - } - if (ptr_reg->type == PTR_TO_PACKET_END) { - verbose(env, "R%d pointer arithmetic on PTR_TO_PACKET_END prohibited\n", - dst); + case CONST_PTR_TO_MAP: + case PTR_TO_PACKET_END: + verbose(env, "R%d pointer arithmetic on %s prohibited\n", + dst, reg_type_str[ptr_reg->type]); return -EACCES; + default: + break; } /* In case of 'scalar += pointer', dst_reg inherits pointer type and id. diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 275b4570b5b8..53439f40e1de 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -3497,7 +3497,7 @@ static struct bpf_test tests[] = { BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .errstr = "R3 pointer arithmetic on PTR_TO_PACKET_END", + .errstr = "R3 pointer arithmetic on pkt_end", .result = REJECT, .prog_type = BPF_PROG_TYPE_SCHED_CLS, }, @@ -4525,7 +4525,7 @@ static struct bpf_test tests[] = { BPF_EXIT_INSN(), }, .fixup_map1 = { 4 }, - .errstr = "R4 pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL", + .errstr = "R4 pointer arithmetic on map_value_or_null", .result = REJECT, .prog_type = BPF_PROG_TYPE_SCHED_CLS }, @@ -4546,7 +4546,7 @@ static struct bpf_test tests[] = { BPF_EXIT_INSN(), }, .fixup_map1 = { 4 }, - .errstr = "R4 pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL", + .errstr = "R4 pointer arithmetic on map_value_or_null", .result = REJECT, .prog_type = BPF_PROG_TYPE_SCHED_CLS }, @@ -4567,7 +4567,7 @@ static struct bpf_test tests[] = { BPF_EXIT_INSN(), }, .fixup_map1 = { 4 }, - .errstr = "R4 pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL", + .errstr = "R4 pointer arithmetic on map_value_or_null", .result = REJECT, .prog_type = BPF_PROG_TYPE_SCHED_CLS }, @@ -6864,7 +6864,7 @@ static struct bpf_test tests[] = { BPF_EXIT_INSN(), }, .fixup_map_in_map = { 3 }, - .errstr = "R1 pointer arithmetic on CONST_PTR_TO_MAP prohibited", + .errstr = "R1 pointer arithmetic on map_ptr prohibited", .result = REJECT, }, { @@ -8538,7 +8538,7 @@ static struct bpf_test tests[] = { BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .errstr = "R3 pointer arithmetic on PTR_TO_PACKET_END", + .errstr = "R3 pointer arithmetic on pkt_end", .result = REJECT, .prog_type = BPF_PROG_TYPE_XDP, }, @@ -8557,7 +8557,7 @@ static struct bpf_test tests[] = { BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }, - .errstr = "R3 pointer arithmetic on PTR_TO_PACKET_END", + .errstr = "R3 pointer arithmetic on pkt_end", .result = REJECT, .prog_type = BPF_PROG_TYPE_XDP, }, -- 2.14.1