From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72D6FC433FE for ; Mon, 3 Oct 2022 08:25:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229801AbiJCIZA (ORCPT ); Mon, 3 Oct 2022 04:25:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229605AbiJCIYX (ORCPT ); Mon, 3 Oct 2022 04:24:23 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6367824F11; Mon, 3 Oct 2022 00:58:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 24CCBB80E90; Mon, 3 Oct 2022 07:24:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C7B4C433C1; Mon, 3 Oct 2022 07:24:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1664781876; bh=CQa9aHIsHJ/Fq5xcdiiAk9NAQbh+vDgkS4lNrFPfjtg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SJlSpQBp1JDg/nO+HXSpHgxLixBYsYFC254YEG2jdlcrX9ctSlu64tTGGa1UzbtKf Wf2tMZfQoHC0cTUWSdiUM3sir4ldIE4eaVGF77cLKpPZ7ml2subsIaqu/aZC/pQphc j9+KFeN/kbgKVaXE1IwbQK/SAEGFb3lmjITLMjlk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Tyler Hicks , Mimi Zohar , Gou Hao Subject: [PATCH 4.19 13/25] ima: Free the entire rule when deleting a list of rules Date: Mon, 3 Oct 2022 09:12:16 +0200 Message-Id: <20221003070715.800430612@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221003070715.406550966@linuxfoundation.org> References: <20221003070715.406550966@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tyler Hicks commit 465aee77aae857b5fcde56ee192b33dc369fba04 upstream. Create a function, ima_free_rule(), to free all memory associated with an ima_rule_entry. Use the new function to fix memory leaks of allocated ima_rule_entry members, such as .fsname and .keyrings, when deleting a list of rules. Make the existing ima_lsm_free_rule() function specific to the LSM audit rule array of an ima_rule_entry and require that callers make an additional call to kfree to free the ima_rule_entry itself. This fixes a memory leak seen when loading by a valid rule that contains an additional piece of allocated memory, such as an fsname, followed by an invalid rule that triggers a policy load failure: # echo -e "dont_measure fsname=securityfs\nbad syntax" > \ /sys/kernel/security/ima/policy -bash: echo: write error: Invalid argument # echo scan > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak unreferenced object 0xffff9bab67ca12c0 (size 16): comm "bash", pid 684, jiffies 4295212803 (age 252.344s) hex dump (first 16 bytes): 73 65 63 75 72 69 74 79 66 73 00 6b 6b 6b 6b a5 securityfs.kkkk. backtrace: [<00000000adc80b1b>] kstrdup+0x2e/0x60 [<00000000d504cb0d>] ima_parse_add_rule+0x7d4/0x1020 [<00000000444825ac>] ima_write_policy+0xab/0x1d0 [<000000002b7f0d6c>] vfs_write+0xde/0x1d0 [<0000000096feedcf>] ksys_write+0x68/0xe0 [<0000000052b544a2>] do_syscall_64+0x56/0xa0 [<000000007ead1ba7>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: f1b08bbcbdaf ("ima: define a new policy condition based on the filesystem name") Fixes: 2b60c0ecedf8 ("IMA: Read keyrings= option from the IMA policy") Signed-off-by: Tyler Hicks Signed-off-by: Mimi Zohar Cc: # 4.19+ Signed-off-by: Gou Hao Signed-off-by: Greg Kroah-Hartman --- security/integrity/ima/ima_policy.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -241,6 +241,21 @@ static int __init default_appraise_polic } __setup("ima_appraise_tcb", default_appraise_policy_setup); +static void ima_free_rule(struct ima_rule_entry *entry) +{ + int i; + + if (!entry) + return; + + kfree(entry->fsname); + for (i = 0; i < MAX_LSM_RULES; i++) { + security_filter_rule_free(entry->lsm[i].rule); + kfree(entry->lsm[i].args_p); + } + kfree(entry); +} + /* * The LSM policy can be reloaded, leaving the IMA LSM based rules referring * to the old, stale LSM policy. Update the IMA LSM based rules to reflect @@ -1040,17 +1055,11 @@ ssize_t ima_parse_add_rule(char *rule) void ima_delete_rules(void) { struct ima_rule_entry *entry, *tmp; - int i; temp_ima_appraise = 0; list_for_each_entry_safe(entry, tmp, &ima_temp_rules, list) { - for (i = 0; i < MAX_LSM_RULES; i++) { - security_filter_rule_free(entry->lsm[i].rule); - kfree(entry->lsm[i].args_p); - } - list_del(&entry->list); - kfree(entry); + ima_free_rule(entry); } }