From patchwork Thu Nov 22 04:49:16 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herton Ronaldo Krzesinski X-Patchwork-Id: 200992 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id 5FED12C0094 for ; Thu, 22 Nov 2012 15:49:29 +1100 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1TbOj4-0004uO-Qa; Thu, 22 Nov 2012 04:49:22 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1TbOj2-0004t8-Lh for kernel-team@lists.ubuntu.com; Thu, 22 Nov 2012 04:49:20 +0000 Received: from 200.146.81.226.dynamic.adsl.gvt.net.br ([200.146.81.226] helo=canonical.com) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1TbOj1-000498-Sb; Thu, 22 Nov 2012 04:49:20 +0000 From: Herton Ronaldo Krzesinski To: Geert Uytterhoeven Subject: [ 3.5.yuz extended stable ] Patch "sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead" has been added to staging queue Date: Thu, 22 Nov 2012 02:49:16 -0200 Message-Id: <1353559756-2993-1-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 Cc: Greg Kroah-Hartman , kernel-team@lists.ubuntu.com X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com This is a note to let you know that I have just added a patch titled sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.yuz tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ From bc1e56e2383d5ee563e4a8e09fc4ce4f5fce4396 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Sat, 29 Sep 2012 22:23:19 +0200 Subject: [PATCH] sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead of strcat() commit 66081a72517a131430dcf986775f3268aafcb546 upstream. The warning check for duplicate sysfs entries can cause a buffer overflow when printing the warning, as strcat() doesn't check buffer sizes. Use strlcat() instead. Since strlcat() doesn't return a pointer to the passed buffer, unlike strcat(), I had to convert the nested concatenation in sysfs_add_one() to an admittedly more obscure comma operator construct, to avoid emitting code for the concatenation if CONFIG_BUG is disabled. Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman Signed-off-by: Herton Ronaldo Krzesinski --- fs/sysfs/dir.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) -- 1.7.9.5 diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index e6bb9b2..5a035b5 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -478,20 +478,18 @@ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) /** * sysfs_pathname - return full path to sysfs dirent * @sd: sysfs_dirent whose path we want - * @path: caller allocated buffer + * @path: caller allocated buffer of size PATH_MAX * * Gives the name "/" to the sysfs_root entry; any path returned * is relative to wherever sysfs is mounted. - * - * XXX: does no error checking on @path size */ static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) { if (sd->s_parent) { sysfs_pathname(sd->s_parent, path); - strcat(path, "/"); + strlcat(path, "/", PATH_MAX); } - strcat(path, sd->s_name); + strlcat(path, sd->s_name, PATH_MAX); return path; } @@ -524,9 +522,11 @@ int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) char *path = kzalloc(PATH_MAX, GFP_KERNEL); WARN(1, KERN_WARNING "sysfs: cannot create duplicate filename '%s'\n", - (path == NULL) ? sd->s_name : - strcat(strcat(sysfs_pathname(acxt->parent_sd, path), "/"), - sd->s_name)); + (path == NULL) ? sd->s_name + : (sysfs_pathname(acxt->parent_sd, path), + strlcat(path, "/", PATH_MAX), + strlcat(path, sd->s_name, PATH_MAX), + path)); kfree(path); }