From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43353) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmOUr-0007Om-Cf for qemu-devel@nongnu.org; Tue, 20 Sep 2016 13:06:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bmOUm-0007RR-7Q for qemu-devel@nongnu.org; Tue, 20 Sep 2016 13:06:16 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:37233 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmOUl-0007QR-W1 for qemu-devel@nongnu.org; Tue, 20 Sep 2016 13:06:12 -0400 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8KH3J7B003207 for ; Tue, 20 Sep 2016 13:06:11 -0400 Received: from e19.ny.us.ibm.com (e19.ny.us.ibm.com [129.33.205.209]) by mx0b-001b2d01.pphosted.com with ESMTP id 25jmr0xqef-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 20 Sep 2016 13:06:11 -0400 Received: from localhost by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 20 Sep 2016 13:06:10 -0400 From: Michael Roth Date: Tue, 20 Sep 2016 12:05:35 -0500 In-Reply-To: <1474391141-16623-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1474391141-16623-1-git-send-email-mdroth@linux.vnet.ibm.com> Message-Id: <1474391141-16623-20-git-send-email-mdroth@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH 19/25] vmw_pvscsi: check page count while initialising descriptor rings List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Prasad J Pandit , Paolo Bonzini From: Prasad J Pandit Vmware Paravirtual SCSI emulation uses command descriptors to process SCSI commands. These descriptors come with their ring buffers. A guest could set the page count for these rings to an arbitrary value, leading to infinite loop or OOB access. Add check to avoid it. Reported-by: Tom Victor Signed-off-by: Prasad J Pandit Message-Id: <1472626169-12989-1-git-send-email-ppandit@redhat.com> Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini (cherry picked from commit 7f61f4690dd153be98900a2a508b88989e692753) Signed-off-by: Michael Roth --- hw/scsi/vmw_pvscsi.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c index fe74d86..b845729 100644 --- a/hw/scsi/vmw_pvscsi.c +++ b/hw/scsi/vmw_pvscsi.c @@ -153,7 +153,7 @@ pvscsi_log2(uint32_t input) return log; } -static int +static void pvscsi_ring_init_data(PVSCSIRingInfo *m, PVSCSICmdDescSetupRings *ri) { int i; @@ -161,10 +161,6 @@ pvscsi_ring_init_data(PVSCSIRingInfo *m, PVSCSICmdDescSetupRings *ri) uint32_t req_ring_size, cmp_ring_size; m->rs_pa = ri->ringsStatePPN << VMW_PAGE_SHIFT; - if ((ri->reqRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES) - || (ri->cmpRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES)) { - return -1; - } req_ring_size = ri->reqRingNumPages * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE; cmp_ring_size = ri->cmpRingNumPages * PVSCSI_MAX_NUM_CMP_ENTRIES_PER_PAGE; txr_len_log2 = pvscsi_log2(req_ring_size - 1); @@ -196,8 +192,6 @@ pvscsi_ring_init_data(PVSCSIRingInfo *m, PVSCSICmdDescSetupRings *ri) /* Flush ring state page changes */ smp_wmb(); - - return 0; } static int @@ -750,7 +744,7 @@ pvscsi_dbg_dump_tx_rings_config(PVSCSICmdDescSetupRings *rc) trace_pvscsi_tx_rings_num_pages("Confirm Ring", rc->cmpRingNumPages); for (i = 0; i < rc->cmpRingNumPages; i++) { - trace_pvscsi_tx_rings_ppn("Confirm Ring", rc->reqRingPPNs[i]); + trace_pvscsi_tx_rings_ppn("Confirm Ring", rc->cmpRingPPNs[i]); } } @@ -783,11 +777,16 @@ pvscsi_on_cmd_setup_rings(PVSCSIState *s) trace_pvscsi_on_cmd_arrived("PVSCSI_CMD_SETUP_RINGS"); - pvscsi_dbg_dump_tx_rings_config(rc); - if (pvscsi_ring_init_data(&s->rings, rc) < 0) { + if (!rc->reqRingNumPages + || rc->reqRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES + || !rc->cmpRingNumPages + || rc->cmpRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES) { return PVSCSI_COMMAND_PROCESSING_FAILED; } + pvscsi_dbg_dump_tx_rings_config(rc); + pvscsi_ring_init_data(&s->rings, rc); + s->rings_info_valid = TRUE; return PVSCSI_COMMAND_PROCESSING_SUCCEEDED; } -- 1.9.1