From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48627) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4vLO-0000gX-SV for qemu-devel@nongnu.org; Wed, 09 Jul 2014 13:07:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X4vLE-0003Br-Eb for qemu-devel@nongnu.org; Wed, 09 Jul 2014 13:07:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:3759) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4vLE-00039p-2D for qemu-devel@nongnu.org; Wed, 09 Jul 2014 13:07:36 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s69H7YRb024982 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Wed, 9 Jul 2014 13:07:35 -0400 From: Markus Armbruster Date: Wed, 9 Jul 2014 19:07:32 +0200 Message-Id: <1404925652-17986-5-git-send-email-armbru@redhat.com> In-Reply-To: <1404925652-17986-1-git-send-email-armbru@redhat.com> References: <1404925652-17986-1-git-send-email-armbru@redhat.com> Subject: [Qemu-devel] [PATCH v4 2.1 4/4] ide: Treat read/write beyond end as invalid List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, famz@redhat.com, uobergfe@redhat.com, stefanha@redhat.com The block layer fails such reads and writes just fine. However, they then get treated like valid operations that fail: the error action gets executed. Unwanted; reporting the error to the guest is the only sensible action. Reject them before passing them to the block layer. This bypasses the error action and I/O accounting. Not quite correct for DMA, because DMA can fail after some success, and when that happens, the part that succeeded isn't counted. Tolerable, because I/O accounting is an inconsistent mess anyway. Signed-off-by: Markus Armbruster --- hw/ide/core.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/hw/ide/core.c b/hw/ide/core.c index 3a38f1e..db191a6 100644 --- a/hw/ide/core.c +++ b/hw/ide/core.c @@ -499,6 +499,18 @@ static void ide_rw_error(IDEState *s) { ide_set_irq(s->bus); } +static bool ide_sect_range_ok(IDEState *s, + uint64_t sector, uint64_t nb_sectors) +{ + uint64_t total_sectors; + + bdrv_get_geometry(s->bs, &total_sectors); + if (sector > total_sectors || nb_sectors > total_sectors - sector) { + return false; + } + return true; +} + static void ide_sector_read_cb(void *opaque, int ret) { IDEState *s = opaque; @@ -554,6 +566,11 @@ void ide_sector_read(IDEState *s) printf("sector=%" PRId64 "\n", sector_num); #endif + if (!ide_sect_range_ok(s, sector_num, n)) { + ide_rw_error(s); + return; + } + s->iov.iov_base = s->io_buffer; s->iov.iov_len = n * BDRV_SECTOR_SIZE; qemu_iovec_init_external(&s->qiov, &s->iov, 1); @@ -671,6 +688,12 @@ void ide_dma_cb(void *opaque, int ret) sector_num, n, s->dma_cmd); #endif + if (!ide_sect_range_ok(s, sector_num, n)) { + dma_buf_commit(s); + ide_dma_error(s); + return; + } + switch (s->dma_cmd) { case IDE_DMA_READ: s->bus->dma->aiocb = dma_bdrv_read(s->bs, &s->sg, sector_num, @@ -790,6 +813,11 @@ void ide_sector_write(IDEState *s) n = s->req_nb_sectors; } + if (!ide_sect_range_ok(s, sector_num, n)) { + ide_rw_error(s); + return; + } + s->iov.iov_base = s->io_buffer; s->iov.iov_len = n * BDRV_SECTOR_SIZE; qemu_iovec_init_external(&s->qiov, &s->iov, 1); -- 1.9.3