From patchwork Mon Aug 5 14:06:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bastien Nocera X-Patchwork-Id: 13753668 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (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 5DCA112D20D for ; Mon, 5 Aug 2024 14:08:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722866927; cv=none; b=QOlHbz+rU4idMlVC/b+w978D2J+SkB2Mo52BdAKh9T62ixDyvXZDEO2V56SDvOXOnvU0wW39mhsSxDu/Ujity+tLai5VRforJe9NQT72Gu04liJyRAqTXAtuYuHqn3Y0Uwr4+pcLvpQOR4krF3RknT4TLTSmhAWXyMAxVrF5HEQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722866927; c=relaxed/simple; bh=0wqNcyaL74Bj6IpXL6qGatPX6UlTMhwbuxzp+0BeNmo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AFckHxRyfzgHUQKig9CNRRzHliJxb9Dt5Pd+2LyzssVhF0DajQKwwQeL8tMPUD9sUpKY0+Z/yawEX8xIrQYwP+ZW1UNNllzfp6CX5xionxx+V8VGV4sblHjmvBV8oPfcIl32WQrNX+9VcBZDgr32D3V18UKRAd1f2PQIbJrXU1I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=hadess.net; spf=pass smtp.mailfrom=hadess.net; arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=hadess.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=hadess.net Received: by mail.gandi.net (Postfix) with ESMTPSA id 82ED52000F; Mon, 5 Aug 2024 14:08:43 +0000 (UTC) From: Bastien Nocera To: linux-bluetooth@vger.kernel.org Cc: Bastien Nocera Subject: [BlueZ 7/8] shared/btsnoop: Avoid underflowing toread variable Date: Mon, 5 Aug 2024 16:06:45 +0200 Message-ID: <20240805140840.1606239-8-hadess@hadess.net> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240805140840.1606239-1-hadess@hadess.net> References: <20240805140840.1606239-1-hadess@hadess.net> Precedence: bulk X-Mailing-List: linux-bluetooth@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-GND-Sasl: hadess@hadess.net Error: INTEGER_OVERFLOW (CWE-190): [#def8] [important] bluez-5.77/src/shared/btsnoop.c:556:3: underflow: The decrement operator on the unsigned variable "toread" might result in an underflow. bluez-5.77/src/shared/btsnoop.c:572:2: overflow_sink: "toread", which might have underflowed, is passed to "read(btsnoop->fd, data, toread)". [Note: The source code implementation of the function has been overridden by a builtin model.] 570| } 571| 572|-> len = read(btsnoop->fd, data, toread); 573| if (len < 0) { 574| btsnoop->aborted = true; --- src/shared/btsnoop.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/src/shared/btsnoop.c b/src/shared/btsnoop.c index bc5f7fcbe84c..bb0bccf0dd01 100644 --- a/src/shared/btsnoop.c +++ b/src/shared/btsnoop.c @@ -530,7 +530,7 @@ bool btsnoop_read_hci(struct btsnoop *btsnoop, struct timeval *tv, } toread = be32toh(pkt.len); - if (toread > BTSNOOP_MAX_PACKET_SIZE) { + if (toread > BTSNOOP_MAX_PACKET_SIZE || toread < 1) { btsnoop->aborted = true; return false; } @@ -569,6 +569,11 @@ bool btsnoop_read_hci(struct btsnoop *btsnoop, struct timeval *tv, return false; } + if (toread == 0) { + btsnoop->aborted = true; + return false; + } + len = read(btsnoop->fd, data, toread); if (len < 0) { btsnoop->aborted = true;