From patchwork Sun Aug 9 15:02:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 262627 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E692C433DF for ; Sun, 9 Aug 2020 15:05:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 27222206B2 for ; Sun, 9 Aug 2020 15:05:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596985504; bh=HsHZHvXJXzNtCj1SyS1h6g6sxV75KZnYa0lr3N8LwBQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=OHktpbbeRsrwERGHYl6mt3MpTHiSw3zkEbsiMrTjhIWosCGM5KEiwUg2M70mv0/sr SAbWJjYLkXhQbBaalMBIB6xs5ceCTtbUY68Nqd02pXbAU6a2yVhbpiq0OlL6zYU9/S pcMPFcnK2Z+u6m4+r6Ivh6vFHJx2YgW68yk9sRgE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726545AbgHIPFD convert rfc822-to-8bit (ORCPT ); Sun, 9 Aug 2020 11:05:03 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:34865 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726386AbgHIPFC (ORCPT ); Sun, 9 Aug 2020 11:05:02 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-278-iqwSq0fAOc6Fcwjy6cSzrA-1; Sun, 09 Aug 2020 11:03:26 -0400 X-MC-Unique: iqwSq0fAOc6Fcwjy6cSzrA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3262980183C; Sun, 9 Aug 2020 15:03:24 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id 188D65F1EA; Sun, 9 Aug 2020 15:03:19 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [RFC PATCH v11 bpf-next 04/14] bpf: Add elem_id pointer as argument to __btf_resolve_size Date: Sun, 9 Aug 2020 17:02:52 +0200 Message-Id: <20200809150302.686149-5-jolsa@kernel.org> In-Reply-To: <20200809150302.686149-1-jolsa@kernel.org> References: <20200809150302.686149-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org If the resolved type is array, make btf_resolve_size return also ID of the elem type. It will be needed in following changes. Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- kernel/bpf/btf.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 6ed4ecc60381..dbc70fedfb44 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -1079,6 +1079,7 @@ static const struct resolve_vertex *env_stack_peak(struct btf_verifier_env *env) * *type_size: (x * y * sizeof(u32)). Hence, *type_size always * corresponds to the return type. * *elem_type: u32 + * *elem_id: id of u32 * *total_nelems: (x * y). Hence, individual elem size is * (*type_size / *total_nelems) * @@ -1086,15 +1087,16 @@ static const struct resolve_vertex *env_stack_peak(struct btf_verifier_env *env) * return type: type "struct X" * *type_size: sizeof(struct X) * *elem_type: same as return type ("struct X") + * *elem_id: 0 * *total_nelems: 1 */ static const struct btf_type * __btf_resolve_size(const struct btf *btf, const struct btf_type *type, u32 *type_size, const struct btf_type **elem_type, - u32 *total_nelems) + u32 *elem_id, u32 *total_nelems) { const struct btf_type *array_type = NULL; - const struct btf_array *array; + const struct btf_array *array = NULL; u32 i, size, nelems = 1; for (i = 0; i < MAX_RESOLVE_DEPTH; i++) { @@ -1146,6 +1148,8 @@ __btf_resolve_size(const struct btf *btf, const struct btf_type *type, *total_nelems = nelems; if (elem_type) *elem_type = type; + if (elem_id) + *elem_id = array ? array->type : 0; return array_type ? : type; } @@ -3984,7 +3988,7 @@ int btf_struct_access(struct bpf_verifier_log *log, mname = __btf_name_by_offset(btf_vmlinux, member->name_off); mtype = __btf_resolve_size(btf_vmlinux, mtype, &msize, - &elem_type, &total_nelems); + &elem_type, NULL, &total_nelems); if (IS_ERR(mtype)) { bpf_log(log, "field %s doesn't have size\n", mname); return -EFAULT; From patchwork Sun Aug 9 15:02:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 262631 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72D34C433DF for ; Sun, 9 Aug 2020 15:03:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46A48206B2 for ; Sun, 9 Aug 2020 15:03:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596985437; bh=b+ayeidIXbgyAiOMn2eKpg6hiyDxc603nbWdjxJmEhI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Zuqw0iA+4nHjeCAJ0uK/ZoU/cDZc72Qi18UlOBICLG2Naotkf+IdMj/KsPmP/ZfXz 0A/y6Owf/Dj3SWLvWjYJv5FsCm004PzQznP2hQHVPBTU4rwnt9jypzsAPLTqOZVCaU UBrWfDv3N9hK1fmLIYM0MMchC5duwMa2rN5Cb7bs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726453AbgHIPDz convert rfc822-to-8bit (ORCPT ); Sun, 9 Aug 2020 11:03:55 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:43694 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726370AbgHIPDi (ORCPT ); Sun, 9 Aug 2020 11:03:38 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-46-VX6_2A22NqW-4z5VV_kxjw-1; Sun, 09 Aug 2020 11:03:33 -0400 X-MC-Unique: VX6_2A22NqW-4z5VV_kxjw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CCF7F1005504; Sun, 9 Aug 2020 15:03:31 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id 92EAD7177B; Sun, 9 Aug 2020 15:03:28 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [RFC PATCH v11 bpf-next 06/14] bpf: Remove recursion call in btf_struct_access Date: Sun, 9 Aug 2020 17:02:54 +0200 Message-Id: <20200809150302.686149-7-jolsa@kernel.org> In-Reply-To: <20200809150302.686149-1-jolsa@kernel.org> References: <20200809150302.686149-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Andrii suggested we can simply jump to again label instead of making recursion call. Suggested-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- kernel/bpf/btf.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index ee0e2a5e6c88..4488c5b03941 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3931,14 +3931,13 @@ int btf_struct_access(struct bpf_verifier_log *log, /* Only allow structure for now, can be relaxed for * other types later. */ - elem_type = btf_type_skip_modifiers(btf_vmlinux, - array_elem->type, NULL); - if (!btf_type_is_struct(elem_type)) + t = btf_type_skip_modifiers(btf_vmlinux, array_elem->type, + NULL); + if (!btf_type_is_struct(t)) goto error; - off = (off - moff) % elem_type->size; - return btf_struct_access(log, elem_type, off, size, atype, - next_btf_id); + off = (off - moff) % t->size; + goto again; error: bpf_log(log, "access beyond struct %s at off %u size %u\n", From patchwork Sun Aug 9 15:02:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 262632 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F523C433DF for ; Sun, 9 Aug 2020 15:03:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D195206B2 for ; Sun, 9 Aug 2020 15:03:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596985429; bh=9V6UyEXHZZpQfAB3UkbwbsLITwHNUDAPMuqrQDgEz8Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0Doupe4eFyUeezaTsFSURXKHdmo5LSi4ay/yk8wzfI7ppYD+PXppSlLkVpivf0cfE hnn2l4hlEX0FeNsdZa11dO1CkbPssCjVqXsi20vwn4axoiBWP25ZKLQqMztpJz6xs/ p/N6BOuInpLr5YRZhijaY7S4smVZP9YHJbnbJo9s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726401AbgHIPDr convert rfc822-to-8bit (ORCPT ); Sun, 9 Aug 2020 11:03:47 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:21941 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726380AbgHIPDn (ORCPT ); Sun, 9 Aug 2020 11:03:43 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-164-wJkT-WaeNtaahFS0yJD24A-1; Sun, 09 Aug 2020 11:03:37 -0400 X-MC-Unique: wJkT-WaeNtaahFS0yJD24A-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 51B47801504; Sun, 9 Aug 2020 15:03:35 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2C00B7177B; Sun, 9 Aug 2020 15:03:32 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [RFC PATCH v11 bpf-next 07/14] bpf: Factor btf_struct_access function Date: Sun, 9 Aug 2020 17:02:55 +0200 Message-Id: <20200809150302.686149-8-jolsa@kernel.org> In-Reply-To: <20200809150302.686149-1-jolsa@kernel.org> References: <20200809150302.686149-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Adding btf_struct_walk function that walks through the struct type + given offset and returns following values: enum bpf_struct_walk_result { /* < 0 error */ WALK_SCALAR = 0, WALK_PTR, WALK_STRUCT, }; WALK_SCALAR - when SCALAR_VALUE is found WALK_PTR - when pointer value is found, its ID is stored in 'next_btf_id' output param WALK_STRUCT - when nested struct object is found, its ID is stored in 'next_btf_id' output param It will be used in following patches to get all nested struct objects for given type and offset. The btf_struct_access now calls btf_struct_walk function, as long as it gets nested structs as return value. Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- kernel/bpf/btf.c | 75 +++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 65 insertions(+), 10 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 4488c5b03941..d8d64201c4e0 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3886,16 +3886,22 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type, return true; } -int btf_struct_access(struct bpf_verifier_log *log, - const struct btf_type *t, int off, int size, - enum bpf_access_type atype, - u32 *next_btf_id) +enum bpf_struct_walk_result { + /* < 0 error */ + WALK_SCALAR = 0, + WALK_PTR, + WALK_STRUCT, +}; + +static int btf_struct_walk(struct bpf_verifier_log *log, + const struct btf_type *t, int off, int size, + u32 *next_btf_id) { u32 i, moff, mtrue_end, msize = 0, total_nelems = 0; const struct btf_type *mtype, *elem_type = NULL; const struct btf_member *member; const char *tname, *mname; - u32 vlen; + u32 vlen, elem_id, mid; again: tname = __btf_name_by_offset(btf_vmlinux, t->name_off); @@ -3966,7 +3972,7 @@ int btf_struct_access(struct bpf_verifier_log *log, */ if (off <= moff && BITS_ROUNDUP_BYTES(end_bit) <= off + size) - return SCALAR_VALUE; + return WALK_SCALAR; /* off may be accessing a following member * @@ -3988,11 +3994,13 @@ int btf_struct_access(struct bpf_verifier_log *log, break; /* type of the field */ + mid = member->type; mtype = btf_type_by_id(btf_vmlinux, member->type); mname = __btf_name_by_offset(btf_vmlinux, member->name_off); mtype = __btf_resolve_size(btf_vmlinux, mtype, &msize, - &elem_type, NULL, &total_nelems, NULL); + &elem_type, &elem_id, &total_nelems, + &mid); if (IS_ERR(mtype)) { bpf_log(log, "field %s doesn't have size\n", mname); return -EFAULT; @@ -4054,6 +4062,7 @@ int btf_struct_access(struct bpf_verifier_log *log, elem_idx = (off - moff) / msize; moff += elem_idx * msize; mtype = elem_type; + mid = elem_id; } /* the 'off' we're looking for is either equal to start @@ -4063,6 +4072,12 @@ int btf_struct_access(struct bpf_verifier_log *log, /* our field must be inside that union or struct */ t = mtype; + /* return if the offset matches the member offset */ + if (off == moff) { + *next_btf_id = mid; + return WALK_STRUCT; + } + /* adjust offset we're looking for */ off -= moff; goto again; @@ -4078,11 +4093,10 @@ int btf_struct_access(struct bpf_verifier_log *log, mname, moff, tname, off, size); return -EACCES; } - stype = btf_type_skip_modifiers(btf_vmlinux, mtype->type, &id); if (btf_type_is_struct(stype)) { *next_btf_id = id; - return PTR_TO_BTF_ID; + return WALK_PTR; } } @@ -4099,12 +4113,53 @@ int btf_struct_access(struct bpf_verifier_log *log, return -EACCES; } - return SCALAR_VALUE; + return WALK_SCALAR; } bpf_log(log, "struct %s doesn't have field at offset %d\n", tname, off); return -EINVAL; } +int btf_struct_access(struct bpf_verifier_log *log, + const struct btf_type *t, int off, int size, + enum bpf_access_type atype __maybe_unused, + u32 *next_btf_id) +{ + int err; + u32 id; + + do { + err = btf_struct_walk(log, t, off, size, &id); + + switch (err) { + case WALK_PTR: + /* If we found the pointer or scalar on t+off, + * we're done. + */ + *next_btf_id = id; + return PTR_TO_BTF_ID; + case WALK_SCALAR: + return SCALAR_VALUE; + case WALK_STRUCT: + /* We found nested struct, so continue the search + * by diving in it. At this point the offset is + * aligned with the new type, so set it to 0. + */ + t = btf_type_by_id(btf_vmlinux, id); + off = 0; + break; + default: + /* It's either error or unknown return value.. + * scream and leave. + */ + if (WARN_ONCE(err > 0, "unknown btf_struct_walk return value")) + return -EINVAL; + return err; + } + } while (t); + + return -EINVAL; +} + int btf_resolve_helper_id(struct bpf_verifier_log *log, const struct bpf_func_proto *fn, int arg) { From patchwork Sun Aug 9 15:02:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 262629 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85934C433E0 for ; Sun, 9 Aug 2020 15:04:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6091B206B5 for ; Sun, 9 Aug 2020 15:04:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596985458; bh=foCw8y64Sqrt6pe47rLC0Q5WhyegpAIZ/uZBoQSR+lo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=lrepq366yD4FoVYzhSgX9kL7e6JTzRsGqIpEyyJl+/ymLTqpEmVAFGKGtiWAe+Iok AKC+l4rn1BvTFnC5Ug21ZIj+wvDCzxMTWu/wBJ5+Nnl6lYvWcKJkqbUlgPeW3Kl0Pb Sb3HxAlnLbJwP0X92ptbtUkbW/gGZ+A28wSKDZOo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726489AbgHIPEN convert rfc822-to-8bit (ORCPT ); Sun, 9 Aug 2020 11:04:13 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:57449 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726415AbgHIPDx (ORCPT ); Sun, 9 Aug 2020 11:03:53 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-474-OqRZ97jJO9GH8k4RlAEqtg-1; Sun, 09 Aug 2020 11:03:45 -0400 X-MC-Unique: OqRZ97jJO9GH8k4RlAEqtg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 33CC080183C; Sun, 9 Aug 2020 15:03:43 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2F7DB72AD1; Sun, 9 Aug 2020 15:03:39 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [RFC PATCH v11 bpf-next 09/14] bpf: Add BTF_SET_START/END macros Date: Sun, 9 Aug 2020 17:02:57 +0200 Message-Id: <20200809150302.686149-10-jolsa@kernel.org> In-Reply-To: <20200809150302.686149-1-jolsa@kernel.org> References: <20200809150302.686149-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Adding support to define sorted set of BTF ID values. Following defines sorted set of BTF ID values: BTF_SET_START(btf_allowlist_d_path) BTF_ID(func, vfs_truncate) BTF_ID(func, vfs_fallocate) BTF_ID(func, dentry_open) BTF_ID(func, vfs_getattr) BTF_ID(func, filp_close) BTF_SET_END(btf_allowlist_d_path) It defines following 'struct btf_id_set' variable to access values and count: struct btf_id_set btf_allowlist_d_path; Adding 'allowed' callback to struct bpf_func_proto, to allow verifier the check on allowed callers. Adding btf_id_set_contains function, which will be used by allowed callbacks to verify the caller's BTF ID value is within allowed set. Also removing extra '\' in __BTF_ID_LIST macro. Added BTF_SET_START_GLOBAL macro for global sets. Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- include/linux/bpf.h | 4 +++ include/linux/btf_ids.h | 51 ++++++++++++++++++++++++++++++++++- kernel/bpf/btf.c | 14 ++++++++++ kernel/bpf/verifier.c | 5 ++++ tools/include/linux/btf_ids.h | 51 ++++++++++++++++++++++++++++++++++- 5 files changed, 123 insertions(+), 2 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 9fead3baa31c..c2026a0a1118 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -309,6 +309,7 @@ struct bpf_func_proto { * for this argument. */ int *ret_btf_id; /* return value btf_id */ + bool (*allowed)(const struct bpf_prog *prog); }; /* bpf_context is intentionally undefined structure. Pointer to bpf_context is @@ -1850,4 +1851,7 @@ enum bpf_text_poke_type { int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t, void *addr1, void *addr2); +struct btf_id_set; +bool btf_id_set_contains(struct btf_id_set *set, u32 id); + #endif /* _LINUX_BPF_H */ diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index 4867d549e3c1..210b086188a3 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -3,6 +3,11 @@ #ifndef _LINUX_BTF_IDS_H #define _LINUX_BTF_IDS_H +struct btf_id_set { + u32 cnt; + u32 ids[]; +}; + #ifdef CONFIG_DEBUG_INFO_BTF #include /* for __PASTE */ @@ -62,7 +67,7 @@ asm( \ ".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ "." #scope " " #name "; \n" \ #name ":; \n" \ -".popsection; \n"); \ +".popsection; \n"); #define BTF_ID_LIST(name) \ __BTF_ID_LIST(name, local) \ @@ -88,12 +93,56 @@ asm( \ ".zero 4 \n" \ ".popsection; \n"); +/* + * The BTF_SET_START/END macros pair defines sorted list of + * BTF IDs plus its members count, with following layout: + * + * BTF_SET_START(list) + * BTF_ID(type1, name1) + * BTF_ID(type2, name2) + * BTF_SET_END(list) + * + * __BTF_ID__set__list: + * .zero 4 + * list: + * __BTF_ID__type1__name1__3: + * .zero 4 + * __BTF_ID__type2__name2__4: + * .zero 4 + * + */ +#define __BTF_SET_START(name, scope) \ +asm( \ +".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ +"." #scope " __BTF_ID__set__" #name "; \n" \ +"__BTF_ID__set__" #name ":; \n" \ +".zero 4 \n" \ +".popsection; \n"); + +#define BTF_SET_START(name) \ +__BTF_ID_LIST(name, local) \ +__BTF_SET_START(name, local) + +#define BTF_SET_START_GLOBAL(name) \ +__BTF_ID_LIST(name, globl) \ +__BTF_SET_START(name, globl) + +#define BTF_SET_END(name) \ +asm( \ +".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ +".size __BTF_ID__set__" #name ", .-" #name " \n" \ +".popsection; \n"); \ +extern struct btf_id_set name; + #else #define BTF_ID_LIST(name) static u32 name[5]; #define BTF_ID(prefix, name) #define BTF_ID_UNUSED #define BTF_ID_LIST_GLOBAL(name) u32 name[1]; +#define BTF_SET_START(name) static struct btf_id_set name = { 0 }; +#define BTF_SET_START_GLOBAL(name) static struct btf_id_set name = { 0 }; +#define BTF_SET_END(name) #endif /* CONFIG_DEBUG_INFO_BTF */ diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index df966acaaeb1..f9ac6935ab3c 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -21,6 +21,8 @@ #include #include #include +#include +#include #include /* BTF (BPF Type Format) is the meta data format which describes @@ -4762,3 +4764,15 @@ u32 btf_id(const struct btf *btf) { return btf->id; } + +static int btf_id_cmp_func(const void *a, const void *b) +{ + const int *pa = a, *pb = b; + + return *pa - *pb; +} + +bool btf_id_set_contains(struct btf_id_set *set, u32 id) +{ + return bsearch(&id, set->ids, set->cnt, sizeof(u32), btf_id_cmp_func) != NULL; +} diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 34d3be105086..85cdcd8a5ea7 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4780,6 +4780,11 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn return -EINVAL; } + if (fn->allowed && !fn->allowed(env->prog)) { + verbose(env, "helper call is not allowed in probe\n"); + return -EINVAL; + } + /* With LD_ABS/IND some JITs save/restore skb from r1. */ changes_data = bpf_helper_changes_pkt_data(fn->func); if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) { diff --git a/tools/include/linux/btf_ids.h b/tools/include/linux/btf_ids.h index 4867d549e3c1..210b086188a3 100644 --- a/tools/include/linux/btf_ids.h +++ b/tools/include/linux/btf_ids.h @@ -3,6 +3,11 @@ #ifndef _LINUX_BTF_IDS_H #define _LINUX_BTF_IDS_H +struct btf_id_set { + u32 cnt; + u32 ids[]; +}; + #ifdef CONFIG_DEBUG_INFO_BTF #include /* for __PASTE */ @@ -62,7 +67,7 @@ asm( \ ".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ "." #scope " " #name "; \n" \ #name ":; \n" \ -".popsection; \n"); \ +".popsection; \n"); #define BTF_ID_LIST(name) \ __BTF_ID_LIST(name, local) \ @@ -88,12 +93,56 @@ asm( \ ".zero 4 \n" \ ".popsection; \n"); +/* + * The BTF_SET_START/END macros pair defines sorted list of + * BTF IDs plus its members count, with following layout: + * + * BTF_SET_START(list) + * BTF_ID(type1, name1) + * BTF_ID(type2, name2) + * BTF_SET_END(list) + * + * __BTF_ID__set__list: + * .zero 4 + * list: + * __BTF_ID__type1__name1__3: + * .zero 4 + * __BTF_ID__type2__name2__4: + * .zero 4 + * + */ +#define __BTF_SET_START(name, scope) \ +asm( \ +".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ +"." #scope " __BTF_ID__set__" #name "; \n" \ +"__BTF_ID__set__" #name ":; \n" \ +".zero 4 \n" \ +".popsection; \n"); + +#define BTF_SET_START(name) \ +__BTF_ID_LIST(name, local) \ +__BTF_SET_START(name, local) + +#define BTF_SET_START_GLOBAL(name) \ +__BTF_ID_LIST(name, globl) \ +__BTF_SET_START(name, globl) + +#define BTF_SET_END(name) \ +asm( \ +".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ +".size __BTF_ID__set__" #name ", .-" #name " \n" \ +".popsection; \n"); \ +extern struct btf_id_set name; + #else #define BTF_ID_LIST(name) static u32 name[5]; #define BTF_ID(prefix, name) #define BTF_ID_UNUSED #define BTF_ID_LIST_GLOBAL(name) u32 name[1]; +#define BTF_SET_START(name) static struct btf_id_set name = { 0 }; +#define BTF_SET_START_GLOBAL(name) static struct btf_id_set name = { 0 }; +#define BTF_SET_END(name) #endif /* CONFIG_DEBUG_INFO_BTF */ From patchwork Sun Aug 9 15:02:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 262630 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AB48C433DF for ; Sun, 9 Aug 2020 15:04:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7544206B5 for ; Sun, 9 Aug 2020 15:04:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596985444; bh=g7ICu+yBQc3qai6PfhWZlxdrJNXMb7+p06n/oF9hqhI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=q3Vm1J3eHiq0Kf7GXU3d1m78SczfIHNIMDsYUuHcjwFuNVKVSMVeQ7Ew4zJvYFVXe 0w8+peKmBxEEUb+fhekpYaIMgamQ2/ZXQHMVCmd6zmMne71KHJfQRTcjgOOGjHx/fN geyGb0vBA1TOAQOwe1WiCGG7pXSU/mrRlePy5nsQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726465AbgHIPED convert rfc822-to-8bit (ORCPT ); Sun, 9 Aug 2020 11:04:03 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:51271 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726448AbgHIPD5 (ORCPT ); Sun, 9 Aug 2020 11:03:57 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-220-15afvRCxO_WxmD4zOUcGgQ-1; Sun, 09 Aug 2020 11:03:48 -0400 X-MC-Unique: 15afvRCxO_WxmD4zOUcGgQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B1C2710059A2; Sun, 9 Aug 2020 15:03:46 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id 878C45F1EA; Sun, 9 Aug 2020 15:03:43 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [RFC PATCH v11 bpf-next 10/14] bpf: Add d_path helper Date: Sun, 9 Aug 2020 17:02:58 +0200 Message-Id: <20200809150302.686149-11-jolsa@kernel.org> In-Reply-To: <20200809150302.686149-1-jolsa@kernel.org> References: <20200809150302.686149-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Adding d_path helper function that returns full path for given 'struct path' object, which needs to be the kernel BTF 'path' object. The path is returned in buffer provided 'buf' of size 'sz' and is zero terminated. bpf_d_path(&file->f_path, buf, size); The helper calls directly d_path function, so there's only limited set of function it can be called from. Adding just very modest set for the start. Updating also bpf.h tools uapi header and adding 'path' to bpf_helpers_doc.py script. Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- include/uapi/linux/bpf.h | 13 +++++++++ kernel/trace/bpf_trace.c | 48 ++++++++++++++++++++++++++++++++++ scripts/bpf_helpers_doc.py | 2 ++ tools/include/uapi/linux/bpf.h | 13 +++++++++ 4 files changed, 76 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index b134e679e9db..338504fb2ea1 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3394,6 +3394,18 @@ union bpf_attr { * A non-negative value equal to or less than *size* on success, * or a negative error in case of failure. * + * long bpf_d_path(struct path *path, char *buf, u32 sz) + * Description + * Return full path for given 'struct path' object, which + * needs to be the kernel BTF 'path' object. The path is + * returned in the provided buffer 'buf' of size 'sz' and + * is zero terminated. + * + * Return + * On success, the strictly positive length of the string, + * including the trailing NUL character. On error, a negative + * value. + * */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3538,6 +3550,7 @@ union bpf_attr { FN(skc_to_tcp_request_sock), \ FN(skc_to_udp6_sock), \ FN(get_task_stack), \ + FN(d_path), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index cb91ef902cc4..d7fc2868cd6f 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1098,6 +1098,52 @@ static const struct bpf_func_proto bpf_send_signal_thread_proto = { .arg1_type = ARG_ANYTHING, }; +BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz) +{ + long len; + char *p; + + if (!sz) + return 0; + + p = d_path(path, buf, sz); + if (IS_ERR(p)) { + len = PTR_ERR(p); + } else { + len = buf + sz - p; + memmove(buf, p, len); + } + + return len; +} + +BTF_SET_START(btf_allowlist_d_path) +BTF_ID(func, vfs_truncate) +BTF_ID(func, vfs_fallocate) +BTF_ID(func, dentry_open) +BTF_ID(func, vfs_getattr) +BTF_ID(func, filp_close) +BTF_SET_END(btf_allowlist_d_path) + +static bool bpf_d_path_allowed(const struct bpf_prog *prog) +{ + return btf_id_set_contains(&btf_allowlist_d_path, prog->aux->attach_btf_id); +} + +BTF_ID_LIST(bpf_d_path_btf_ids) +BTF_ID(struct, path) + +static const struct bpf_func_proto bpf_d_path_proto = { + .func = bpf_d_path, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_BTF_ID, + .arg2_type = ARG_PTR_TO_MEM, + .arg3_type = ARG_CONST_SIZE_OR_ZERO, + .btf_id = bpf_d_path_btf_ids, + .allowed = bpf_d_path_allowed, +}; + const struct bpf_func_proto * bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { @@ -1579,6 +1625,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return prog->expected_attach_type == BPF_TRACE_ITER ? &bpf_seq_write_proto : NULL; + case BPF_FUNC_d_path: + return &bpf_d_path_proto; default: return raw_tp_prog_func_proto(func_id, prog); } diff --git a/scripts/bpf_helpers_doc.py b/scripts/bpf_helpers_doc.py index 5bfa448b4704..08388173973f 100755 --- a/scripts/bpf_helpers_doc.py +++ b/scripts/bpf_helpers_doc.py @@ -432,6 +432,7 @@ class PrinterHelpers(Printer): 'struct __sk_buff', 'struct sk_msg_md', 'struct xdp_md', + 'struct path', ] known_types = { '...', @@ -472,6 +473,7 @@ class PrinterHelpers(Printer): 'struct tcp_request_sock', 'struct udp6_sock', 'struct task_struct', + 'struct path', } mapped_types = { 'u8': '__u8', diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index b134e679e9db..338504fb2ea1 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3394,6 +3394,18 @@ union bpf_attr { * A non-negative value equal to or less than *size* on success, * or a negative error in case of failure. * + * long bpf_d_path(struct path *path, char *buf, u32 sz) + * Description + * Return full path for given 'struct path' object, which + * needs to be the kernel BTF 'path' object. The path is + * returned in the provided buffer 'buf' of size 'sz' and + * is zero terminated. + * + * Return + * On success, the strictly positive length of the string, + * including the trailing NUL character. On error, a negative + * value. + * */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3538,6 +3550,7 @@ union bpf_attr { FN(skc_to_tcp_request_sock), \ FN(skc_to_udp6_sock), \ FN(get_task_stack), \ + FN(d_path), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper From patchwork Sun Aug 9 15:03:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 262628 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85432C433E0 for ; Sun, 9 Aug 2020 15:04:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 64D57206B5 for ; Sun, 9 Aug 2020 15:04:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596985475; bh=xAPcaXED/v5BUdzak1fdSCSP5FA28V/dyzvm3eYJ9kw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=G9dyJSkScbdczRy7SZakcpvn9Noy4Rv/dxUNbTqP9d9y2AtOE0VXp4HgG3JFOcMi/ UFuxi9ZtcH5gyikfCfoSn/bkKf64hIMprbmv3nN9k/tcjBpjEXk2IcETxd9uIT3Tj8 DDAUIg1irXvBGCk+eIDbPZNVBTZz5S4rW65EVQDc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726515AbgHIPEe convert rfc822-to-8bit (ORCPT ); Sun, 9 Aug 2020 11:04:34 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:39563 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726492AbgHIPEa (ORCPT ); Sun, 9 Aug 2020 11:04:30 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-89-pIWPNUzoMB6Lj9tiEk6pRg-1; Sun, 09 Aug 2020 11:04:01 -0400 X-MC-Unique: pIWPNUzoMB6Lj9tiEk6pRg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C8602800477; Sun, 9 Aug 2020 15:03:59 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.79]) by smtp.corp.redhat.com (Postfix) with ESMTP id A7D8F5F1EA; Sun, 9 Aug 2020 15:03:55 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: Wenbo Zhang , netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [RFC PATCH v11 bpf-next 13/14] selftests/bpf: Add test for d_path helper Date: Sun, 9 Aug 2020 17:03:01 +0200 Message-Id: <20200809150302.686149-14-jolsa@kernel.org> In-Reply-To: <20200809150302.686149-1-jolsa@kernel.org> References: <20200809150302.686149-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Adding test for d_path helper which is pretty much copied from Wenbo Zhang's test for bpf_get_fd_path, which never made it in. The test is doing fstat/close on several fd types, and verifies we got the d_path helper working on kernel probes for vfs_getattr/filp_close functions. Original-patch-by: Wenbo Zhang Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- .../testing/selftests/bpf/prog_tests/d_path.c | 147 ++++++++++++++++++ .../testing/selftests/bpf/progs/test_d_path.c | 58 +++++++ 2 files changed, 205 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/d_path.c create mode 100644 tools/testing/selftests/bpf/progs/test_d_path.c diff --git a/tools/testing/selftests/bpf/prog_tests/d_path.c b/tools/testing/selftests/bpf/prog_tests/d_path.c new file mode 100644 index 000000000000..058765da17e6 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/d_path.c @@ -0,0 +1,147 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include +#include +#include +#include + +#define MAX_PATH_LEN 128 +#define MAX_FILES 7 + +#include "test_d_path.skel.h" + +static int duration; + +static struct { + __u32 cnt; + char paths[MAX_FILES][MAX_PATH_LEN]; +} src; + +static int set_pathname(int fd, pid_t pid) +{ + char buf[MAX_PATH_LEN]; + + snprintf(buf, MAX_PATH_LEN, "/proc/%d/fd/%d", pid, fd); + return readlink(buf, src.paths[src.cnt++], MAX_PATH_LEN); +} + +static int trigger_fstat_events(pid_t pid) +{ + int sockfd = -1, procfd = -1, devfd = -1; + int localfd = -1, indicatorfd = -1; + int pipefd[2] = { -1, -1 }; + struct stat fileStat; + int ret = -1; + + /* unmountable pseudo-filesystems */ + if (CHECK(pipe(pipefd) < 0, "trigger", "pipe failed\n")) + return ret; + /* unmountable pseudo-filesystems */ + sockfd = socket(AF_INET, SOCK_STREAM, 0); + if (CHECK(sockfd < 0, "trigger", "scoket failed\n")) + goto out_close; + /* mountable pseudo-filesystems */ + procfd = open("/proc/self/comm", O_RDONLY); + if (CHECK(procfd < 0, "trigger", "open /proc/self/comm failed\n")) + goto out_close; + devfd = open("/dev/urandom", O_RDONLY); + if (CHECK(devfd < 0, "trigger", "open /dev/urandom failed\n")) + goto out_close; + localfd = open("/tmp/d_path_loadgen.txt", O_CREAT | O_RDONLY); + if (CHECK(localfd < 0, "trigger", "open /tmp/d_path_loadgen.txt failed\n")) + goto out_close; + /* bpf_d_path will return path with (deleted) */ + remove("/tmp/d_path_loadgen.txt"); + indicatorfd = open("/tmp/", O_PATH); + if (CHECK(indicatorfd < 0, "trigger", "open /tmp/ failed\n")) + goto out_close; + + ret = set_pathname(pipefd[0], pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for pipe[0]\n")) + goto out_close; + ret = set_pathname(pipefd[1], pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for pipe[1]\n")) + goto out_close; + ret = set_pathname(sockfd, pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for socket\n")) + goto out_close; + ret = set_pathname(procfd, pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for proc\n")) + goto out_close; + ret = set_pathname(devfd, pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for dev\n")) + goto out_close; + ret = set_pathname(localfd, pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for file\n")) + goto out_close; + ret = set_pathname(indicatorfd, pid); + if (CHECK(ret < 0, "trigger", "set_pathname failed for dir\n")) + goto out_close; + + /* triggers vfs_getattr */ + fstat(pipefd[0], &fileStat); + fstat(pipefd[1], &fileStat); + fstat(sockfd, &fileStat); + fstat(procfd, &fileStat); + fstat(devfd, &fileStat); + fstat(localfd, &fileStat); + fstat(indicatorfd, &fileStat); + +out_close: + /* triggers filp_close */ + close(pipefd[0]); + close(pipefd[1]); + close(sockfd); + close(procfd); + close(devfd); + close(localfd); + close(indicatorfd); + return ret; +} + +void test_d_path(void) +{ + struct test_d_path__bss *bss; + struct test_d_path *skel; + int err; + + skel = test_d_path__open_and_load(); + if (CHECK(!skel, "setup", "d_path skeleton failed\n")) + goto cleanup; + + err = test_d_path__attach(skel); + if (CHECK(err, "setup", "attach failed: %d\n", err)) + goto cleanup; + + bss = skel->bss; + bss->my_pid = getpid(); + + err = trigger_fstat_events(bss->my_pid); + if (err < 0) + goto cleanup; + + for (int i = 0; i < MAX_FILES; i++) { + CHECK(strncmp(src.paths[i], bss->paths_stat[i], MAX_PATH_LEN), + "check", + "failed to get stat path[%d]: %s vs %s\n", + i, src.paths[i], bss->paths_stat[i]); + CHECK(strncmp(src.paths[i], bss->paths_close[i], MAX_PATH_LEN), + "check", + "failed to get close path[%d]: %s vs %s\n", + i, src.paths[i], bss->paths_close[i]); + /* The d_path helper returns size plus NUL char, hence + 1 */ + CHECK(bss->rets_stat[i] != strlen(bss->paths_stat[i]) + 1, + "check", + "failed to match stat return [%d]: %d vs %zd [%s]\n", + i, bss->rets_stat[i], strlen(bss->paths_stat[i]) + 1, + bss->paths_stat[i]); + CHECK(bss->rets_close[i] != strlen(bss->paths_stat[i]) + 1, + "check", + "failed to match stat return [%d]: %d vs %zd [%s]\n", + i, bss->rets_close[i], strlen(bss->paths_close[i]) + 1, + bss->paths_stat[i]); + } + +cleanup: + test_d_path__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_d_path.c b/tools/testing/selftests/bpf/progs/test_d_path.c new file mode 100644 index 000000000000..61f007855649 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_d_path.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include +#include + +#define MAX_PATH_LEN 128 +#define MAX_FILES 7 + +pid_t my_pid = 0; +__u32 cnt_stat = 0; +__u32 cnt_close = 0; +char paths_stat[MAX_FILES][MAX_PATH_LEN] = {}; +char paths_close[MAX_FILES][MAX_PATH_LEN] = {}; +int rets_stat[MAX_FILES] = {}; +int rets_close[MAX_FILES] = {}; + +SEC("fentry/vfs_getattr") +int BPF_PROG(prog_stat, struct path *path, struct kstat *stat, + __u32 request_mask, unsigned int query_flags) +{ + pid_t pid = bpf_get_current_pid_tgid() >> 32; + __u32 cnt = cnt_stat; + int ret; + + if (pid != my_pid) + return 0; + + if (cnt >= MAX_FILES) + return 0; + ret = bpf_d_path(path, paths_stat[cnt], MAX_PATH_LEN); + + rets_stat[cnt] = ret; + cnt_stat++; + return 0; +} + +SEC("fentry/filp_close") +int BPF_PROG(prog_close, struct file *file, void *id) +{ + pid_t pid = bpf_get_current_pid_tgid() >> 32; + __u32 cnt = cnt_close; + int ret; + + if (pid != my_pid) + return 0; + + if (cnt >= MAX_FILES) + return 0; + ret = bpf_d_path(&file->f_path, + paths_close[cnt], MAX_PATH_LEN); + + rets_close[cnt] = ret; + cnt_close++; + return 0; +} + +char _license[] SEC("license") = "GPL";