diff options
author | Prasad J Pandit <pjp@fedoraproject.org> | 2016-09-14 15:09:12 +0530 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-09-14 12:25:14 +0200 |
commit | d251157ac1928191af851d199a9ff255d330bec9 (patch) | |
tree | a5761fe4b12c9e7908934e2ea01d920698bcec59 | |
parent | 58268c8d3d051f7fe329dcd42a9284cb4e3b3e31 (diff) |
scsi: pvscsi: limit process IO loop to ring size
Vmware Paravirtual SCSI emulator while processing IO requests
could run into an infinite loop if 'pvscsi_ring_pop_req_descr'
always returned positive value. Limit IO loop to the ring size.
Cc: qemu-stable@nongnu.org
Reported-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-Id: <1473845952-30785-1-git-send-email-ppandit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r-- | hw/scsi/vmw_pvscsi.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c index babac5a68a..a5ce7dea8e 100644 --- a/hw/scsi/vmw_pvscsi.c +++ b/hw/scsi/vmw_pvscsi.c @@ -247,8 +247,11 @@ static hwaddr pvscsi_ring_pop_req_descr(PVSCSIRingInfo *mgr) { uint32_t ready_ptr = RS_GET_FIELD(mgr, reqProdIdx); + uint32_t ring_size = PVSCSI_MAX_NUM_PAGES_REQ_RING + * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE; - if (ready_ptr != mgr->consumed_ptr) { + if (ready_ptr != mgr->consumed_ptr + && ready_ptr - mgr->consumed_ptr < ring_size) { uint32_t next_ready_ptr = mgr->consumed_ptr++ & mgr->txr_len_mask; uint32_t next_ready_page = |