From mboxrd@z Thu Jan 1 00:00:00 1970 From: Akinobu Mita Subject: [PATCH v2 2/6] block: fix SG_[GS]ET_RESERVED_SIZE ioctl when max_sectors is huge Date: Mon, 2 Jun 2014 22:56:45 +0900 Message-ID: <1401717409-5236-3-git-send-email-akinobu.mita@gmail.com> References: <1401717409-5236-1-git-send-email-akinobu.mita@gmail.com> Return-path: Received: from mail-pd0-f169.google.com ([209.85.192.169]:52033 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754631AbaFBN5K (ORCPT ); Mon, 2 Jun 2014 09:57:10 -0400 Received: by mail-pd0-f169.google.com with SMTP id w10so3461837pde.28 for ; Mon, 02 Jun 2014 06:57:09 -0700 (PDT) In-Reply-To: <1401717409-5236-1-git-send-email-akinobu.mita@gmail.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org Cc: Akinobu Mita , Christoph Hellwig , Jens Axboe , "James E.J. Bottomley" , Douglas Gilbert SG_GET_RESERVED_SIZE and SG_SET_RESERVED_SIZE ioctls access a reserved buffer in bytes as int type. The value needs to be capped at the request queue's max_sectors. But integer overflow is not correctly handled in the calculation when converting max_sectors from sectors to bytes. Signed-off-by: Akinobu Mita Reviewed-by: Christoph Hellwig Cc: Christoph Hellwig Cc: Jens Axboe Cc: "James E.J. Bottomley" Cc: Douglas Gilbert Cc: linux-scsi@vger.kernel.org --- No change from previous version. block/scsi_ioctl.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index 2648797..6174bba 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -82,9 +82,18 @@ static int sg_set_timeout(struct request_queue *q, int __user *p) return err; } +static int max_sectors_bytes(struct request_queue *q) +{ + unsigned int max_sectors = queue_max_sectors(q); + + max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9); + + return max_sectors << 9; +} + static int sg_get_reserved_size(struct request_queue *q, int __user *p) { - unsigned val = min(q->sg_reserved_size, queue_max_sectors(q) << 9); + int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q)); return put_user(val, p); } @@ -98,10 +107,8 @@ static int sg_set_reserved_size(struct request_queue *q, int __user *p) if (size < 0) return -EINVAL; - if (size > (queue_max_sectors(q) << 9)) - size = queue_max_sectors(q) << 9; - q->sg_reserved_size = size; + q->sg_reserved_size = min(size, max_sectors_bytes(q)); return 0; } -- 1.9.1