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 925D37868F; Mon, 4 Mar 2024 21:55:50 +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=1709589350; cv=none; b=WTG3rxKIfAOrtoyk1+hezuJY5zI6TSx4xlYexBk62RdSWEyESVzXQwgVm7BIUFqND/ttie/8PFaxfzR378cWwktjx9rTJ95reg9BGTVFo4DZelHQWGrWy+jLjGrXoazp4z8hq/T5i39chR4x4QkPBa+gXA2PH37R+bDKEn6fd54= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709589350; c=relaxed/simple; bh=9AlQ1D7Ir3nBoTE76zeTP+rZIv/Vg+xYLIYn+4bwrr4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jtZaawT7FLh/TkhPYVvSTH0PmBA3apC+mRZzJX9JqjAaSiJeo5Rfp5Asakuaac8uwiPJja1Lf3zwa/GvTGw8p6/BQegdURThr1+fyW9fOzQUz29p4TNr1NnLKZt2ltfTwKkCakrI7Df7bxA1tkO8Q9X5/w1ehfknS3PAL1wwlU0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=B8qckFQo; 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="B8qckFQo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 265C8C433F1; Mon, 4 Mar 2024 21:55:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709589350; bh=9AlQ1D7Ir3nBoTE76zeTP+rZIv/Vg+xYLIYn+4bwrr4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B8qckFQoK+njlhqNPexSdR6bzm+dZWcOzanU0bTPf+a8B+1Y0bVEQbi39u/Dh3vZ3 oygJ3Fo28ogfSxNJCO4DtCxObVjjlv8/8o05efAlcBBY5I/NMb6oCP1K0m/UCrHBFZ lUKzF70S/+kXzeSubeE74Po6cX51CeiOc7js8aGM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Edward Adam Davis , Boris Burkov , David Sterba , syzbot+33f23b49ac24f986c9e8@syzkaller.appspotmail.com Subject: [PATCH 5.15 51/84] btrfs: dev-replace: properly validate device names Date: Mon, 4 Mar 2024 21:24:24 +0000 Message-ID: <20240304211544.067154481@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240304211542.332206551@linuxfoundation.org> References: <20240304211542.332206551@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Sterba commit 9845664b9ee47ce7ee7ea93caf47d39a9d4552c4 upstream. There's a syzbot report that device name buffers passed to device replace are not properly checked for string termination which could lead to a read out of bounds in getname_kernel(). Add a helper that validates both source and target device name buffers. For devid as the source initialize the buffer to empty string in case something tries to read it later. This was originally analyzed and fixed in a different way by Edward Adam Davis (see links). Link: https://lore.kernel.org/linux-btrfs/000000000000d1a1d1060cc9c5e7@google.com/ Link: https://lore.kernel.org/linux-btrfs/tencent_44CA0665C9836EF9EEC80CB9E7E206DF5206@qq.com/ CC: stable@vger.kernel.org # 4.19+ CC: Edward Adam Davis Reported-and-tested-by: syzbot+33f23b49ac24f986c9e8@syzkaller.appspotmail.com Reviewed-by: Boris Burkov Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/dev-replace.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -763,6 +763,23 @@ leave: return ret; } +static int btrfs_check_replace_dev_names(struct btrfs_ioctl_dev_replace_args *args) +{ + if (args->start.srcdevid == 0) { + if (memchr(args->start.srcdev_name, 0, + sizeof(args->start.srcdev_name)) == NULL) + return -ENAMETOOLONG; + } else { + args->start.srcdev_name[0] = 0; + } + + if (memchr(args->start.tgtdev_name, 0, + sizeof(args->start.tgtdev_name)) == NULL) + return -ENAMETOOLONG; + + return 0; +} + int btrfs_dev_replace_by_ioctl(struct btrfs_fs_info *fs_info, struct btrfs_ioctl_dev_replace_args *args) { @@ -775,10 +792,9 @@ int btrfs_dev_replace_by_ioctl(struct bt default: return -EINVAL; } - - if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') || - args->start.tgtdev_name[0] == '\0') - return -EINVAL; + ret = btrfs_check_replace_dev_names(args); + if (ret < 0) + return ret; ret = btrfs_dev_replace_start(fs_info, args->start.tgtdev_name, args->start.srcdevid,