From patchwork Fri Aug 21 20:34:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Moore X-Patchwork-Id: 11730533 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D0ED916B1 for ; Fri, 21 Aug 2020 20:34:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B4EAF20724 for ; Fri, 21 Aug 2020 20:34:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=paul-moore-com.20150623.gappssmtp.com header.i=@paul-moore-com.20150623.gappssmtp.com header.b="NhZ9BlLw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726757AbgHUUe5 (ORCPT ); Fri, 21 Aug 2020 16:34:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726440AbgHUUey (ORCPT ); Fri, 21 Aug 2020 16:34:54 -0400 Received: from mail-qv1-xf41.google.com (mail-qv1-xf41.google.com [IPv6:2607:f8b0:4864:20::f41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C51B1C061574 for ; Fri, 21 Aug 2020 13:34:54 -0700 (PDT) Received: by mail-qv1-xf41.google.com with SMTP id t6so1227355qvw.1 for ; Fri, 21 Aug 2020 13:34:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=paul-moore-com.20150623.gappssmtp.com; s=20150623; h=subject:from:to:cc:date:message-id:user-agent:mime-version :content-transfer-encoding; bh=gtYkus8ZVVc5pmWJLu8BIzUlBoq3dgwoix4MDLg9CP8=; b=NhZ9BlLwXuB+GFtl7cKffYH0zhfkWL/WSkQtfHgqgfDHRf5pL5PPk1dZVv9acUrgeW BE413GiRIotoOjZwD6VeTM2HLzyqxWxDKxIAtQkaPG4uNkREAmp+G9oV0IrcpXynP46t 8VizZ4qQn2NbP0d1s9ez5FHu/QYS2HdRkGgc02r15zn3wkfjrFmqwdj1bF+QlZA8a1/g 0NUV9wPeIseYV79MxRR5zEhMm0OWXCpUSMOkc+4wFZRxRaj1DA8gErM1GTC9wGkCssqw DnVAPGFkTNYZCxTSniValX1oejiDpHcKvomdCBMAJN6PZ1VNW+LdlMnnNI7c5pN3NesQ PJTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:date:message-id:user-agent :mime-version:content-transfer-encoding; bh=gtYkus8ZVVc5pmWJLu8BIzUlBoq3dgwoix4MDLg9CP8=; b=Q+MV9eGOVTyI5wn6EkbF+7y64a83gmnYfAIccqQHf+RLKfwhTaLm2lNWd4hvRvF6UM 2h8IeAK9D2KlZNIIGbioxoI4tzVeWHQFTLqAJ1pKOFuZezWFV4gnIxY8kF/bMtdD9V3T qBjxnsaVw7caE1+HzxxBj2wMzZ9JM67SafswjloL+Fe1CmLUqjgu6B+GC/udXhw3r6Kq 8PnLsGTmUArOLl0hAoqVkvUBXRPbFbUzqnApCsHEi5dGXKZQLtAuNS9VDdISIKNztgxA KQuMe4Z58CpSM5NaSahNfCEZ3qiflyjIqF/JjMFWYXNI93kgv9OPCrdYKWb+qtJXacBX ZVgg== X-Gm-Message-State: AOAM5318qemhIhTikh4WO85M7Grv9RuZkLmLs8R+Ru7c8EfSyvXD6kAV PcZ+W0D6/Zk/mPYm7OLsYXrD X-Google-Smtp-Source: ABdhPJz8j+1pCA53E3Grk45ESNsN0PVvN11X7njTJ3Ea12itZgwJb9nO1rLFL84r1uLmlvhcUWyxPw== X-Received: by 2002:a05:6214:1108:: with SMTP id e8mr4020105qvs.237.1598042093697; Fri, 21 Aug 2020 13:34:53 -0700 (PDT) Received: from localhost (pool-96-230-24-152.bstnma.fios.verizon.net. [96.230.24.152]) by smtp.gmail.com with ESMTPSA id k1sm2675427qkf.12.2020.08.21.13.34.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Aug 2020 13:34:52 -0700 (PDT) Subject: [net PATCH] netlabel: fix problems with mapping removal From: Paul Moore To: netdev@vger.kernel.org Cc: linux-security-module@vger.kernel.org, selinux@vger.kernel.org, Stephen Smalley Date: Fri, 21 Aug 2020 16:34:52 -0400 Message-ID: <159804209207.16190.14955035148979265114.stgit@sifl> User-Agent: StGit/0.23 MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: This patch fixes two main problems seen when removing NetLabel mappings: memory leaks and potentially extra audit noise. The memory leaks are caused by not properly free'ing the mapping's address selector struct when free'ing the entire entry as well as not properly cleaning up a temporary mapping entry when adding new address selectors to an existing entry. This patch fixes both these problems such that kmemleak reports no NetLabel associated leaks after running the SELinux test suite. The potentially extra audit noise was caused by the auditing code in netlbl_domhsh_remove_entry() being called regardless of the entry's validity. If another thread had already marked the entry as invalid, but not removed/free'd it from the list of mappings, then it was possible that an additional mapping removal audit record would be generated. This patch fixes this by returning early from the removal function when the entry was previously marked invalid. This change also had the side benefit of improving the code by decreasing the indentation level of large chunk of code by one (accounting for most of the diffstat). Fixes: 63c416887437 ("netlabel: Add network address selectors to the NetLabel/LSM domain mapping") Reported-by: Stephen Smalley Signed-off-by: Paul Moore --- net/netlabel/netlabel_domainhash.c | 59 ++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 29 deletions(-) diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c index d07de2c0fbc7..f73a8382c275 100644 --- a/net/netlabel/netlabel_domainhash.c +++ b/net/netlabel/netlabel_domainhash.c @@ -85,6 +85,7 @@ static void netlbl_domhsh_free_entry(struct rcu_head *entry) kfree(netlbl_domhsh_addr6_entry(iter6)); } #endif /* IPv6 */ + kfree(ptr->def.addrsel); } kfree(ptr->domain); kfree(ptr); @@ -537,6 +538,8 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry, goto add_return; } #endif /* IPv6 */ + /* cleanup the new entry since we've moved everything over */ + netlbl_domhsh_free_entry(&entry->rcu); } else ret_val = -EINVAL; @@ -580,6 +583,12 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, { int ret_val = 0; struct audit_buffer *audit_buf; + struct netlbl_af4list *iter4; + struct netlbl_domaddr4_map *map4; +#if IS_ENABLED(CONFIG_IPV6) + struct netlbl_af6list *iter6; + struct netlbl_domaddr6_map *map6; +#endif /* IPv6 */ if (entry == NULL) return -ENOENT; @@ -597,6 +606,9 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, ret_val = -ENOENT; spin_unlock(&netlbl_domhsh_lock); + if (ret_val) + return ret_val; + audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info); if (audit_buf != NULL) { audit_log_format(audit_buf, @@ -606,40 +618,29 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry, audit_log_end(audit_buf); } - if (ret_val == 0) { - struct netlbl_af4list *iter4; - struct netlbl_domaddr4_map *map4; -#if IS_ENABLED(CONFIG_IPV6) - struct netlbl_af6list *iter6; - struct netlbl_domaddr6_map *map6; -#endif /* IPv6 */ - - switch (entry->def.type) { - case NETLBL_NLTYPE_ADDRSELECT: - netlbl_af4list_foreach_rcu(iter4, - &entry->def.addrsel->list4) { - map4 = netlbl_domhsh_addr4_entry(iter4); - cipso_v4_doi_putdef(map4->def.cipso); - } + switch (entry->def.type) { + case NETLBL_NLTYPE_ADDRSELECT: + netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4) { + map4 = netlbl_domhsh_addr4_entry(iter4); + cipso_v4_doi_putdef(map4->def.cipso); + } #if IS_ENABLED(CONFIG_IPV6) - netlbl_af6list_foreach_rcu(iter6, - &entry->def.addrsel->list6) { - map6 = netlbl_domhsh_addr6_entry(iter6); - calipso_doi_putdef(map6->def.calipso); - } + netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6) { + map6 = netlbl_domhsh_addr6_entry(iter6); + calipso_doi_putdef(map6->def.calipso); + } #endif /* IPv6 */ - break; - case NETLBL_NLTYPE_CIPSOV4: - cipso_v4_doi_putdef(entry->def.cipso); - break; + break; + case NETLBL_NLTYPE_CIPSOV4: + cipso_v4_doi_putdef(entry->def.cipso); + break; #if IS_ENABLED(CONFIG_IPV6) - case NETLBL_NLTYPE_CALIPSO: - calipso_doi_putdef(entry->def.calipso); - break; + case NETLBL_NLTYPE_CALIPSO: + calipso_doi_putdef(entry->def.calipso); + break; #endif /* IPv6 */ - } - call_rcu(&entry->rcu, netlbl_domhsh_free_entry); } + call_rcu(&entry->rcu, netlbl_domhsh_free_entry); return ret_val; }