From nobody Mon Feb 9 05:53:09 2026 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 B8C4FC6FD1D for ; Thu, 23 Mar 2023 12:36:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231876AbjCWMgu (ORCPT ); Thu, 23 Mar 2023 08:36:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231848AbjCWMgm (ORCPT ); Thu, 23 Mar 2023 08:36:42 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A33071CF41; Thu, 23 Mar 2023 05:36:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679574998; x=1711110998; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=OAAjRWa/GMe3Eyh4EzhGnD6aqq4E5v6Kahs4zyE3gnQ=; b=JlFNifkK2vnleKWitd8wXZANVEYiicxQLwnQXd87xpz+53z7ivSXme5e LFqVkMfbRvJP46qEMHryBS4MDn3vyHQ+D1UxsHJbeOuoWsMY98G84facW ouoTF3riOFnLy1aoNup3eimJ1HjUhqhC4DWNtKLGXvj+TW12ykCmx2Osi AYcn1BTuhfIMtuVkSEPkuaB3T/QXZ6YEetm/zC/ERsg6Jk4wrj1hV2qsJ r64rGSUDMpLDsJe/jq5xyPWPfuodcVCnqk/z4PEIUMq14kfIz/uX89CpO 8NmlNF78jg8jhnqn2Q6VuREvkwyJwWI7ERw0rqVDLQyjlPdhVa1S2k6kO g==; X-IronPort-AV: E=McAfee;i="6600,9927,10657"; a="341011540" X-IronPort-AV: E=Sophos;i="5.98,283,1673942400"; d="scan'208";a="341011540" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2023 05:36:23 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10657"; a="856466578" X-IronPort-AV: E=Sophos;i="5.98,283,1673942400"; d="scan'208";a="856466578" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 23 Mar 2023 05:36:20 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id 237F794; Thu, 23 Mar 2023 14:37:07 +0200 (EET) From: Andy Shevchenko To: Kees Cook , Greg Kroah-Hartman , Andy Shevchenko , Cezary Rojewski , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Theodore Ts'o" , Jan Kara , Andy Shevchenko , "Rafael J. Wysocki" , Jan Kara Subject: [PATCH v2 1/3] jbd2: Avoid printing outside the boundary of the buffer Date: Thu, 23 Mar 2023 14:37:02 +0200 Message-Id: <20230323123704.37983-2-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.40.0.1.gaa8946217a0b In-Reply-To: <20230323123704.37983-1-andriy.shevchenko@linux.intel.com> References: <20230323123704.37983-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Theoretically possible that "%pg" will take all room for the j_devname and hence the "-%lu" will go outside the boundary due to unconditional sprintf() in use. To make this code more robust, replace two sequential s*printf():s by a single call and then replace forbidden character. It's possible to do this way, because '/' won't ever be in the result of "-%lu". Signed-off-by: Andy Shevchenko Reviewed-by: Jan Kara --- fs/jbd2/journal.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 8ae419152ff6..6e17f8f94dfd 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1491,7 +1491,6 @@ journal_t *jbd2_journal_init_inode(struct inode *inod= e) { journal_t *journal; sector_t blocknr; - char *p; int err =3D 0; =20 blocknr =3D 0; @@ -1515,9 +1514,8 @@ journal_t *jbd2_journal_init_inode(struct inode *inod= e) =20 journal->j_inode =3D inode; snprintf(journal->j_devname, sizeof(journal->j_devname), - "%pg", journal->j_dev); - p =3D strreplace(journal->j_devname, '/', '!'); - sprintf(p, "-%lu", journal->j_inode->i_ino); + "%pg-%lu", journal->j_dev, journal->j_inode->i_ino); + strreplace(journal->j_devname, '/', '!'); jbd2_stats_proc_init(journal); =20 return journal; --=20 2.40.0.1.gaa8946217a0b From nobody Mon Feb 9 05:53:09 2026 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 7C58AC6FD1C for ; Thu, 23 Mar 2023 12:36:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231857AbjCWMgo (ORCPT ); Thu, 23 Mar 2023 08:36:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38078 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231599AbjCWMgi (ORCPT ); Thu, 23 Mar 2023 08:36:38 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 277DC26C15; Thu, 23 Mar 2023 05:36:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679574984; x=1711110984; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=r+ztcOnn0m/uP+HZ0+0cEy+nf6BiVCkiWkOotsDK89M=; b=c4rvo83jhJ2nLQrSFnjHUHfdytcNbPKzN+60XOeC4QdOZ//LKMBE109/ K9YWWal5oWizE74v6jjf9us71lofeENL13gOMmUsRibdAbAHwfo6C8OpK 2UY3VUi3qMkj5hk1b2dYPUfSuIxEC7y6JYK+MT/nbT1N7enGNlRe9rhVn 8S2p2LT76zSzbS70IbJWVBJSl5cduKwuTIoxpzuomdqnOaoOUzN9ATPz0 kANW5cnyt4A2SaP1im7c70+Cz3aHdnVbSh0EOzdaIv33wwbOOOz8inqnS R3savMneYomRoxUCWnTn+H2b0B3fO6ixz6c8GrhnN3zaJW6vL6clR3qd1 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10657"; a="341011527" X-IronPort-AV: E=Sophos;i="5.98,283,1673942400"; d="scan'208";a="341011527" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2023 05:36:23 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10657"; a="856466573" X-IronPort-AV: E=Sophos;i="5.98,283,1673942400"; d="scan'208";a="856466573" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 23 Mar 2023 05:36:20 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id 35871250; Thu, 23 Mar 2023 14:37:07 +0200 (EET) From: Andy Shevchenko To: Kees Cook , Greg Kroah-Hartman , Andy Shevchenko , Cezary Rojewski , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Theodore Ts'o" , Jan Kara , Andy Shevchenko , "Rafael J. Wysocki" Subject: [PATCH v2 2/3] lib/string_helpers: Change returned value of the strreplace() Date: Thu, 23 Mar 2023 14:37:03 +0200 Message-Id: <20230323123704.37983-3-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.40.0.1.gaa8946217a0b In-Reply-To: <20230323123704.37983-1-andriy.shevchenko@linux.intel.com> References: <20230323123704.37983-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" It's more useful to return the pointer to the string itself with strreplace(), so it may be used like attr->name =3D strreplace(name, '/', '_'); While at it, amend the kernel documentation. Signed-off-by: Andy Shevchenko --- include/linux/string.h | 2 +- lib/string_helpers.c | 12 ++++++++---- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/include/linux/string.h b/include/linux/string.h index a7bff7ed3cb0..cb0c24ce0826 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -169,7 +169,7 @@ static inline void memcpy_flushcache(void *dst, const v= oid *src, size_t cnt) #endif =20 void *memchr_inv(const void *s, int c, size_t n); -char *strreplace(char *s, char old, char new); +char *strreplace(char *str, char old, char new); =20 extern void kfree_const(const void *x); =20 diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 230020a2e076..d3b1dd718daf 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -979,18 +979,22 @@ EXPORT_SYMBOL(__sysfs_match_string); =20 /** * strreplace - Replace all occurrences of character in string. - * @s: The string to operate on. + * @str: The string to operate on. * @old: The character being replaced. * @new: The character @old is replaced with. * - * Returns pointer to the nul byte at the end of @s. + * Replaces the each @old character with a @new one in the given string @s= tr. + * + * Return: pointer to the string @str itself. */ -char *strreplace(char *s, char old, char new) +char *strreplace(char *str, char old, char new) { + char *s =3D str; + for (; *s; ++s) if (*s =3D=3D old) *s =3D new; - return s; + return str; } EXPORT_SYMBOL(strreplace); =20 --=20 2.40.0.1.gaa8946217a0b From nobody Mon Feb 9 05:53:09 2026 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 5E79EC7619A for ; Thu, 23 Mar 2023 12:36:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231767AbjCWMgk (ORCPT ); Thu, 23 Mar 2023 08:36:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231758AbjCWMgi (ORCPT ); Thu, 23 Mar 2023 08:36:38 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13B071B56F; Thu, 23 Mar 2023 05:36:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679574984; x=1711110984; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Uqba7KW+LSTrR6KDuN+F/tgiTmPx6AhRcJexGJYfzL0=; b=DVpEUyVcB9cuHQaevin9Hs+FrKfkjYEBilsuB7NZEcmJ68Q6q5r1gG31 aoUldmS7ijsb/RnEvdcQ/AGw8VWqYvT6mbmJ6cLoVQsk4OO66IizRsR+9 fn8AHZvaZmXMiEgWNtxCHFpi7wc7WMocpWf/Xj/0JxGQnz565QA0Mnj+P zrHZePsVE6HiBlKFLldJVcYA02CXlD85JCEo5fBX1YHKugzTDpCtEztlt 4Dlx6rJ5qYBKowjEn0nlMqB6bOFEQbUtxhFd/TaiD7InqMnD1Z5Gy7Vof +QYZaieWqldzU0n3Z5ZzMpOa9gz1waTZ3elG1kpxSQOv/AjfNMM09BSk6 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10657"; a="404359764" X-IronPort-AV: E=Sophos;i="5.98,283,1673942400"; d="scan'208";a="404359764" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2023 05:36:23 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10657"; a="675681050" X-IronPort-AV: E=Sophos;i="5.98,283,1673942400"; d="scan'208";a="675681050" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga007.jf.intel.com with ESMTP; 23 Mar 2023 05:36:20 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id 3AE4C176; Thu, 23 Mar 2023 14:37:07 +0200 (EET) From: Andy Shevchenko To: Kees Cook , Greg Kroah-Hartman , Andy Shevchenko , Cezary Rojewski , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Theodore Ts'o" , Jan Kara , Andy Shevchenko , "Rafael J. Wysocki" Subject: [PATCH v2 3/3] kobject: Use return value of strreplace() Date: Thu, 23 Mar 2023 14:37:04 +0200 Message-Id: <20230323123704.37983-4-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.40.0.1.gaa8946217a0b In-Reply-To: <20230323123704.37983-1-andriy.shevchenko@linux.intel.com> References: <20230323123704.37983-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Since strreplace() returns the pointer to the string itself, we may use it directly in the code. Signed-off-by: Andy Shevchenko --- lib/kobject.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/lib/kobject.c b/lib/kobject.c index f79a434e1231..16d530f9c174 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -281,8 +281,7 @@ int kobject_set_name_vargs(struct kobject *kobj, const = char *fmt, kfree_const(s); if (!t) return -ENOMEM; - strreplace(t, '/', '!'); - s =3D t; + s =3D strreplace(t, '/', '!'); } kfree_const(kobj->name); kobj->name =3D s; --=20 2.40.0.1.gaa8946217a0b