nvme: Fix unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)

The shift operation on nlb gives a 32 bit result if no type cast is
applied. This bug was reported by Coverity.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-id: 1426348844-8793-1-git-send-email-sw@weilnetz.de
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 0f3dfb9..1e07166 100644 (file)
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -222,7 +222,7 @@ static uint16_t nvme_rw(NvmeCtrl *n, NvmeNamespace *ns, NvmeCmd *cmd,
 
     uint8_t lba_index  = NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas);
     uint8_t data_shift = ns->id_ns.lbaf[lba_index].ds;
-    uint64_t data_size = nlb << data_shift;
+    uint64_t data_size = (uint64_t)nlb << data_shift;
     uint64_t aio_slba  = slba << (data_shift - BDRV_SECTOR_BITS);
     int is_write = rw->opcode == NVME_CMD_WRITE ? 1 : 0;