From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D99CCFBF2; Sat, 3 Feb 2024 04:11:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706933511; cv=none; b=IrBttJY++q880xHMjfwANJRBj6VhXsfZncYc8feUR0mMvMRNGfU+M+mIp8SoQ5nSC4V1wxIwlI8eZTnlg68N4lCQwBNISTFk4y2fP65sleGuiTnhceHKF7tkzb6MeI09RMBpw7Y6Dvrc3JKCawjtw7vZVapG9UzcnRVKmmb0Pzg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706933511; c=relaxed/simple; bh=uFc26fBd6YUNLASkbzuaUh2x2Jp4izCai2nlcc51sf8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=snV5EO9Sj0BYWyPJTX8S+LbFizTJEFOrdMZasbZyzF659RwzeQw+CJZVWJ0DLQEV2e1U/AM1ML456rwjPrkcoE1xCj8DzcaXea49x912R9XA65Qt2lT5jHl75KooMY5b6ModVr+0fAfIW+7fn891EPNMzk8dNEmhbm28tLm9Wv8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OiEyRYof; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="OiEyRYof" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A18D7C433F1; Sat, 3 Feb 2024 04:11:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1706933511; bh=uFc26fBd6YUNLASkbzuaUh2x2Jp4izCai2nlcc51sf8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OiEyRYofQ3zyL84RkIgNHWuxBON6GPhV53mVZQEW2rzerS+y2Gs5LqoWTFQMWBSN2 z6pKjjJaS5iflZMJsnp2z42rmRK+xrbi1W9W4cYHA3VLoPLdii5zSpJ/ZKDonNGeOT 0FYNXQc9vIc9WB4FXWU/RdeU9xpeIA65UEVfSw8E= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Joel Granados , kernel test robot , Luis Chamberlain , Sasha Levin Subject: [PATCH 6.6 048/322] sysctl: Fix out of bounds access for empty sysctl registers Date: Fri, 2 Feb 2024 20:02:25 -0800 Message-ID: <20240203035400.659252071@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240203035359.041730947@linuxfoundation.org> References: <20240203035359.041730947@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joel Granados [ Upstream commit 315552310c7de92baea4e570967066569937a843 ] When registering tables to the sysctl subsystem there is a check to see if header is a permanently empty directory (used for mounts). This check evaluates the first element of the ctl_table. This results in an out of bounds evaluation when registering empty directories. The function register_sysctl_mount_point now passes a ctl_table of size 1 instead of size 0. It now relies solely on the type to identify a permanently empty register. Make sure that the ctl_table has at least one element before testing for permanent emptiness. Signed-off-by: Joel Granados Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202311201431.57aae8f3-oliver.sang@intel.com Signed-off-by: Luis Chamberlain Signed-off-by: Sasha Levin --- fs/proc/proc_sysctl.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index de484195f49f..5b5cdc747cef 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -44,7 +44,7 @@ static struct ctl_table sysctl_mount_point[] = { */ struct ctl_table_header *register_sysctl_mount_point(const char *path) { - return register_sysctl_sz(path, sysctl_mount_point, 0); + return register_sysctl(path, sysctl_mount_point); } EXPORT_SYMBOL(register_sysctl_mount_point); @@ -233,7 +233,8 @@ static int insert_header(struct ctl_dir *dir, struct ctl_table_header *header) return -EROFS; /* Am I creating a permanently empty directory? */ - if (sysctl_is_perm_empty_ctl_table(header->ctl_table)) { + if (header->ctl_table_size > 0 && + sysctl_is_perm_empty_ctl_table(header->ctl_table)) { if (!RB_EMPTY_ROOT(&dir->root)) return -EINVAL; sysctl_set_perm_empty_ctl_header(dir_h); @@ -1213,6 +1214,10 @@ static bool get_links(struct ctl_dir *dir, struct ctl_table_header *tmp_head; struct ctl_table *entry, *link; + if (header->ctl_table_size == 0 || + sysctl_is_perm_empty_ctl_table(header->ctl_table)) + return true; + /* Are there links available for every entry in table? */ list_for_each_table_entry(entry, header) { const char *procname = entry->procname; -- 2.43.0