From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:33444 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932350AbeE1KmC (ORCPT ); Mon, 28 May 2018 06:42:02 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Piotr Gabriel Kosinski , Daniel Shapira , Kees Cook , Jens Axboe Subject: [PATCH 4.14 021/496] sr: pass down correctly sized SCSI sense buffer Date: Mon, 28 May 2018 11:56:46 +0200 Message-Id: <20180528100320.483371030@linuxfoundation.org> In-Reply-To: <20180528100319.498712256@linuxfoundation.org> References: <20180528100319.498712256@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jens Axboe commit f7068114d45ec55996b9040e98111afa56e010fe upstream. We're casting the CDROM layer request_sense to the SCSI sense buffer, but the former is 64 bytes and the latter is 96 bytes. As we generally allocate these on the stack, we end up blowing up the stack. Fix this by wrapping the scsi_execute() call with a properly sized sense buffer, and copying back the bits for the CDROM layer. Cc: stable@vger.kernel.org Reported-by: Piotr Gabriel Kosinski Reported-by: Daniel Shapira Tested-by: Kees Cook Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request") Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/sr_ioctl.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/drivers/scsi/sr_ioctl.c +++ b/drivers/scsi/sr_ioctl.c @@ -188,9 +188,13 @@ int sr_do_ioctl(Scsi_CD *cd, struct pack struct scsi_device *SDev; struct scsi_sense_hdr sshdr; int result, err = 0, retries = 0; + unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE], *senseptr = NULL; SDev = cd->device; + if (cgc->sense) + senseptr = sense_buffer; + retry: if (!scsi_block_when_processing_errors(SDev)) { err = -ENODEV; @@ -198,10 +202,12 @@ int sr_do_ioctl(Scsi_CD *cd, struct pack } result = scsi_execute(SDev, cgc->cmd, cgc->data_direction, - cgc->buffer, cgc->buflen, - (unsigned char *)cgc->sense, &sshdr, + cgc->buffer, cgc->buflen, senseptr, &sshdr, cgc->timeout, IOCTL_RETRIES, 0, 0, NULL); + if (cgc->sense) + memcpy(cgc->sense, sense_buffer, sizeof(*cgc->sense)); + /* Minimal error checking. Ignore cases we know about, and report the rest. */ if (driver_byte(result) != 0) { switch (sshdr.sense_key) {