From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x225c0N6Axspb358y44YX2E3FzJG1m019C6Gx/mhc1dMtVsaSvejwAbuzJ66OevXwyFljDHhj ARC-Seal: i=1; a=rsa-sha256; t=1518323640; cv=none; d=google.com; s=arc-20160816; b=HXaTlnml6/1048+F77/TQ3YLAK/wmwH4xcnrTlMh6rL2AXK1SzRYjUutnFxU3Dhck4 Te7dCAw4alxfzXUz61skYr9wWKtj/VoRKoQSXIr+vi7Ny7SR+a3cwLDau/vswvC6FGML ufMXz6YIEnin3sIVeIuQ5tH7+tgNArofnJawG3arIQQJ9TZTb3dnnnLeBvJwLDEqO7l0 3g39wjXBxkwtbKYzrd4fFGri/4J2wMGCFnT8JG+D6CTtRo3WQwWor55RkHAkteghVtKV vkjgzQhU3khpwQOtS8QNJohEhEMudhDLqNjFGaIrSedGE8lVr4qG7gFSZhEJzfyAStgb 0gJA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=in-reply-to:subject:message-id:date:cc:to:from:mime-version :content-transfer-encoding:content-disposition :arc-authentication-results; bh=rMy33fHqp9sKqi8USjRU+KVA4CHkHEng9jR89rIobiY=; b=AKo78qwEliy/tPNAoVeMcKGUhiTtNgTE5/HsXicFlajXav1NyRWCEunDiovfGwE26E 610bD9nMYnCfSK/pF+jOX6f4DKvVauYQompAz51JnMFpyYZIlFwyLQYS6o8jwYIUxpsl 1pbsTxAWXQ4IxnxmkAoZA0QJn1083hxdPWJCpRl7wk8cwUQvSHhjerW85bdGEljsV3LM dKsjjo8qJiVGU34Kg5rEPunKR9ff/JwXnzgbqMV+phLVUDc10v049BntB7BkKX0rNru6 CIE1wPRKOrcPnY8goa4ZrvQgylrw0y7mLu5NcIarhQRyDoavAcAX4/fbMFqUUH+BGNK2 NaDw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of ben@decadent.org.uk designates 88.96.1.126 as permitted sender) smtp.mailfrom=ben@decadent.org.uk Authentication-Results: mx.google.com; spf=pass (google.com: domain of ben@decadent.org.uk designates 88.96.1.126 as permitted sender) smtp.mailfrom=ben@decadent.org.uk Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Shuah Khan" , "Greg Kroah-Hartman" , "Secunia Research" Date: Sun, 11 Feb 2018 04:31:11 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 124/136] usbip: fix stub_rx: harden CMD_SUBMIT path to handle malicious input In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1592077709661989304?= X-GMAIL-MSGID: =?utf-8?q?1592077729220791195?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.16.54-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Shuah Khan commit c6688ef9f29762e65bce325ef4acd6c675806366 upstream. Harden CMD_SUBMIT path to handle malicious input that could trigger large memory allocations. Add checks to validate transfer_buffer_length and number_of_packets to protect against bad input requesting for unbounded memory allocations. Validate early in get_pipe() and return failure. Reported-by: Secunia Research Signed-off-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings --- drivers/staging/usbip/stub_rx.c | 35 +++++++++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-) --- a/drivers/staging/usbip/stub_rx.c +++ b/drivers/staging/usbip/stub_rx.c @@ -336,11 +336,13 @@ static struct stub_priv *stub_priv_alloc return priv; } -static int get_pipe(struct stub_device *sdev, int epnum, int dir) +static int get_pipe(struct stub_device *sdev, struct usbip_header *pdu) { struct usb_device *udev = sdev->udev; struct usb_host_endpoint *ep; struct usb_endpoint_descriptor *epd = NULL; + int epnum = pdu->base.ep; + int dir = pdu->base.direction; if (epnum < 0 || epnum > 15) goto err_ret; @@ -353,6 +355,15 @@ static int get_pipe(struct stub_device * goto err_ret; epd = &ep->desc; + + /* validate transfer_buffer_length */ + if (pdu->u.cmd_submit.transfer_buffer_length > INT_MAX) { + dev_err(&sdev->udev->dev, + "CMD_SUBMIT: -EMSGSIZE transfer_buffer_length %d\n", + pdu->u.cmd_submit.transfer_buffer_length); + return -1; + } + if (usb_endpoint_xfer_control(epd)) { if (dir == USBIP_DIR_OUT) return usb_sndctrlpipe(udev, epnum); @@ -375,6 +386,21 @@ static int get_pipe(struct stub_device * } if (usb_endpoint_xfer_isoc(epd)) { + /* validate packet size and number of packets */ + unsigned int maxp, packets, bytes; + + maxp = usb_endpoint_maxp(epd); + maxp *= usb_endpoint_maxp_mult(epd); + bytes = pdu->u.cmd_submit.transfer_buffer_length; + packets = DIV_ROUND_UP(bytes, maxp); + + if (pdu->u.cmd_submit.number_of_packets < 0 || + pdu->u.cmd_submit.number_of_packets > packets) { + dev_err(&sdev->udev->dev, + "CMD_SUBMIT: isoc invalid num packets %d\n", + pdu->u.cmd_submit.number_of_packets); + return -1; + } if (dir == USBIP_DIR_OUT) return usb_sndisocpipe(udev, epnum); else @@ -383,7 +409,7 @@ static int get_pipe(struct stub_device * err_ret: /* NOT REACHED */ - dev_err(&sdev->udev->dev, "get pipe() invalid epnum %d\n", epnum); + dev_err(&sdev->udev->dev, "CMD_SUBMIT: invalid epnum %d\n", epnum); return -1; } @@ -448,7 +474,7 @@ static void stub_recv_cmd_submit(struct struct stub_priv *priv; struct usbip_device *ud = &sdev->ud; struct usb_device *udev = sdev->udev; - int pipe = get_pipe(sdev, pdu->base.ep, pdu->base.direction); + int pipe = get_pipe(sdev, pdu); if (pipe == -1) return; @@ -471,7 +497,8 @@ static void stub_recv_cmd_submit(struct } /* allocate urb transfer buffer, if needed */ - if (pdu->u.cmd_submit.transfer_buffer_length > 0) { + if (pdu->u.cmd_submit.transfer_buffer_length > 0 && + pdu->u.cmd_submit.transfer_buffer_length <= INT_MAX) { priv->urb->transfer_buffer = kzalloc(pdu->u.cmd_submit.transfer_buffer_length, GFP_KERNEL);