From patchwork Wed Jun 3 18:20:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yannick Cote X-Patchwork-Id: 208435 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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED 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 4D33FC433E1 for ; Wed, 3 Jun 2020 18:21:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21B082053B for ; Wed, 3 Jun 2020 18:21:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="L2U1Piwy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726170AbgFCSV5 (ORCPT ); Wed, 3 Jun 2020 14:21:57 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:29847 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726096AbgFCSVm (ORCPT ); Wed, 3 Jun 2020 14:21:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591208500; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rAog9oXLl/KPRUT67WnomCQCFdAZfZBa0BLOwUhaVok=; b=L2U1Piwy/mz0uEunuiY49FmOFJ7bn7IczmcK62Zm2FQFxqS3EXAEoMsSzciBMq5dV6JN84 atVEw8iyc6vgpl358xC7K8ywAHSkqjLU0ED42iwifKmEuuNSugFVu+D4nE/p2Vg95rEACi tgw2z4lYQR1tlXkQyJ0+h8Z/h/lmX+w= 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-379-vX4zcfqUObyawnGnGgs7yg-1; Wed, 03 Jun 2020 14:21:37 -0400 X-MC-Unique: vX4zcfqUObyawnGnGgs7yg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D92961005510; Wed, 3 Jun 2020 18:21:35 +0000 (UTC) Received: from dm.redhat.com (unknown [10.10.67.78]) by smtp.corp.redhat.com (Postfix) with ESMTP id D10E95D9CD; Wed, 3 Jun 2020 18:21:34 +0000 (UTC) From: Yannick Cote To: live-patching@vger.kernel.org Cc: linux-kselftest@vger.kernel.org, joe.lawrence@redhat.com, linux-kernel@vger.kernel.org, pmladek@suse.com, mbenes@suse.cz, kamalesh@linux.vnet.ibm.com Subject: [PATCH v2 2/4] selftests/livepatch: rework test-klp-shadow-vars Date: Wed, 3 Jun 2020 14:20:56 -0400 Message-Id: <20200603182058.109470-3-ycote@redhat.com> In-Reply-To: <20200603182058.109470-1-ycote@redhat.com> References: <20200603182058.109470-1-ycote@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org The initial idea was to make a change to please cppcheck and remove void pointer arithmetics found a few times: portability: 'obj' is of type 'void *'. When using void pointers in calculations, the behaviour is undefined. [arithOperationsOnVoidPointer] The rest of the changes are to help make the test read as an example while continuing to verify the shadow variable code. The logic of the test is unchanged but restructured to use descriptive names. Reviewed-by: Petr Mladek Reviewed-by: Kamalesh Babulal Acked-by: Miroslav Benes Acked-by: Joe Lawrence Signed-off-by: Yannick Cote --- lib/livepatch/test_klp_shadow_vars.c | 101 +++++++++++++++------------ 1 file changed, 57 insertions(+), 44 deletions(-) diff --git a/lib/livepatch/test_klp_shadow_vars.c b/lib/livepatch/test_klp_shadow_vars.c index f0b5a1d24e55..ec2635cff974 100644 --- a/lib/livepatch/test_klp_shadow_vars.c +++ b/lib/livepatch/test_klp_shadow_vars.c @@ -109,8 +109,7 @@ static void shadow_free(void *obj, unsigned long id, klp_shadow_dtor_t dtor) static void shadow_free_all(unsigned long id, klp_shadow_dtor_t dtor) { klp_shadow_free_all(id, dtor); - pr_info("klp_%s(id=0x%lx, dtor=PTR%d)\n", - __func__, id, ptr_id(dtor)); + pr_info("klp_%s(id=0x%lx, dtor=PTR%d)\n", __func__, id, ptr_id(dtor)); } @@ -124,8 +123,7 @@ static int shadow_ctor(void *obj, void *shadow_data, void *ctor_data) return -EINVAL; *sv = *var; - pr_info("%s: PTR%d -> PTR%d\n", - __func__, ptr_id(sv), ptr_id(*var)); + pr_info("%s: PTR%d -> PTR%d\n", __func__, ptr_id(sv), ptr_id(*var)); return 0; } @@ -138,49 +136,63 @@ static void shadow_dtor(void *obj, void *shadow_data) __func__, ptr_id(obj), ptr_id(sv)); } -static int test_klp_shadow_vars_init(void) -{ - void *obj = THIS_MODULE; - int id = 0x1234; - gfp_t gfp_flags = GFP_KERNEL; +/* dynamically created obj fields have the following shadow var id values */ +#define SV_ID1 0x1234 +#define SV_ID2 0x1235 - int var1, var2, var3, var4; - int *pv1, *pv2, *pv3, *pv4; - int **sv1, **sv2, **sv3, **sv4; +/* + * The main test case adds/removes new fields (shadow var) to each of these + * test structure instances. The last group of fields in the struct represent + * the idea that shadow variables may be added and removed to and from the + * struct during execution. + */ +struct test_object { + /* add anything here below and avoid to define an empty struct */ + struct shadow_ptr sp; - int **sv; + /* these represent shadow vars added and removed with SV_ID{1,2} */ + /* char nfield1; */ + /* int nfield2; */ +}; - pv1 = &var1; - pv2 = &var2; - pv3 = &var3; - pv4 = &var4; +static int test_klp_shadow_vars_init(void) +{ + struct test_object obj1, obj2, obj3; + char nfield1, nfield2, *pnfield1, *pnfield2, **sv1, **sv2; + int nfield3, nfield4, *pnfield3, *pnfield4, **sv3, **sv4; + void **sv; + + pnfield1 = &nfield1; + pnfield2 = &nfield2; + pnfield3 = &nfield3; + pnfield4 = &nfield4; ptr_id(NULL); - ptr_id(pv1); - ptr_id(pv2); - ptr_id(pv3); - ptr_id(pv4); + ptr_id(pnfield1); + ptr_id(pnfield2); + ptr_id(pnfield3); + ptr_id(pnfield4); /* * With an empty shadow variable hash table, expect not to find * any matches. */ - sv = shadow_get(obj, id); + sv = shadow_get(&obj1, SV_ID1); if (!sv) pr_info(" got expected NULL result\n"); /* * Allocate a few shadow variables with different and . */ - sv1 = shadow_alloc(obj, id, sizeof(pv1), gfp_flags, shadow_ctor, &pv1); + sv1 = shadow_alloc(&obj1, SV_ID1, sizeof(pnfield1), GFP_KERNEL, shadow_ctor, &pnfield1); if (!sv1) return -ENOMEM; - sv2 = shadow_alloc(obj + 1, id, sizeof(pv2), gfp_flags, shadow_ctor, &pv2); + sv2 = shadow_alloc(&obj2, SV_ID1, sizeof(pnfield2), GFP_KERNEL, shadow_ctor, &pnfield2); if (!sv2) return -ENOMEM; - sv3 = shadow_alloc(obj, id + 1, sizeof(pv3), gfp_flags, shadow_ctor, &pv3); + sv3 = shadow_alloc(&obj1, SV_ID2, sizeof(pnfield3), GFP_KERNEL, shadow_ctor, &pnfield3); if (!sv3) return -ENOMEM; @@ -188,23 +200,24 @@ static int test_klp_shadow_vars_init(void) * Verify we can find our new shadow variables and that they point * to expected data. */ - sv = shadow_get(obj, id); + sv = shadow_get(&obj1, SV_ID1); if (!sv) return -EINVAL; - if (sv == sv1 && *sv1 == pv1) + if ((char **)sv == sv1 && *sv1 == pnfield1) pr_info(" got expected PTR%d -> PTR%d result\n", ptr_id(sv1), ptr_id(*sv1)); - sv = shadow_get(obj + 1, id); + sv = shadow_get(&obj2, SV_ID1); if (!sv) return -EINVAL; - if (sv == sv2 && *sv2 == pv2) + if ((char **)sv == sv2 && *sv2 == pnfield2) pr_info(" got expected PTR%d -> PTR%d result\n", ptr_id(sv2), ptr_id(*sv2)); - sv = shadow_get(obj, id + 1); + + sv = shadow_get(&obj1, SV_ID2); if (!sv) return -EINVAL; - if (sv == sv3 && *sv3 == pv3) + if ((int **)sv == sv3 && *sv3 == pnfield3) pr_info(" got expected PTR%d -> PTR%d result\n", ptr_id(sv3), ptr_id(*sv3)); @@ -212,14 +225,14 @@ static int test_klp_shadow_vars_init(void) * Allocate or get a few more, this time with the same , . * The second invocation should return the same shadow var. */ - sv4 = shadow_get_or_alloc(obj + 2, id, sizeof(pv4), gfp_flags, shadow_ctor, &pv4); + sv4 = shadow_get_or_alloc(&obj3, SV_ID1, sizeof(pnfield4), GFP_KERNEL, shadow_ctor, &pnfield4); if (!sv4) return -ENOMEM; - sv = shadow_get_or_alloc(obj + 2, id, sizeof(pv4), gfp_flags, shadow_ctor, &pv4); + sv = shadow_get_or_alloc(&obj3, SV_ID1, sizeof(pnfield4), GFP_KERNEL, shadow_ctor, &pnfield4); if (!sv) return -EINVAL; - if (sv == sv4 && *sv4 == pv4) + if ((int **)sv == sv4 && *sv4 == pnfield4) pr_info(" got expected PTR%d -> PTR%d result\n", ptr_id(sv4), ptr_id(*sv4)); @@ -227,36 +240,36 @@ static int test_klp_shadow_vars_init(void) * Free the shadow variables and check that we can no * longer find them. */ - shadow_free(obj, id, shadow_dtor); /* sv1 */ - sv = shadow_get(obj, id); + shadow_free(&obj1, SV_ID1, shadow_dtor); /* sv1 */ + sv = shadow_get(&obj1, SV_ID1); if (!sv) pr_info(" got expected NULL result\n"); - shadow_free(obj + 1, id, shadow_dtor); /* sv2 */ - sv = shadow_get(obj + 1, id); + shadow_free(&obj2, SV_ID1, shadow_dtor); /* sv2 */ + sv = shadow_get(&obj2, SV_ID1); if (!sv) pr_info(" got expected NULL result\n"); - shadow_free(obj + 2, id, shadow_dtor); /* sv4 */ - sv = shadow_get(obj + 2, id); + shadow_free(&obj3, SV_ID1, shadow_dtor); /* sv4 */ + sv = shadow_get(&obj3, SV_ID1); if (!sv) pr_info(" got expected NULL result\n"); /* * We should still find an variable. */ - sv = shadow_get(obj, id + 1); + sv = shadow_get(&obj1, SV_ID2); if (!sv) return -EINVAL; - if (sv == sv3 && *sv3 == pv3) + if ((int **)sv == sv3 && *sv3 == pnfield3) pr_info(" got expected PTR%d -> PTR%d result\n", ptr_id(sv3), ptr_id(*sv3)); /* * Free all the variables, too. */ - shadow_free_all(id + 1, shadow_dtor); /* sv3 */ - sv = shadow_get(obj, id); + shadow_free_all(SV_ID2, shadow_dtor); /* sv3 */ + sv = shadow_get(&obj1, SV_ID1); if (!sv) pr_info(" shadow_get() got expected NULL result\n");