hw/net/rocker: Avoid undefined shifts with more than 31 ports

In rocker_port_phys_link_status() and rocker_port_phys_enable_read()
we construct a 64-bit value with one bit per front-panel port.
However we accidentally do the shift as 32-bit arithmetic, which
means that if there are more than 31 front-panel ports this is
undefined behaviour.

Fix the problem by ensuring we use 64-bit arithmetic for the whole
calculation. (We won't ever shift off the 64-bit value because
ROCKER_FP_PORTS_MAX is 62.)

Resolves: Coverity CID 1487121, 1487160
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>

diff --git a/hw/net/rocker/rocker.c b/hw/net/rocker/rocker.c
index 31f2340fb910963bbfb77cf7e41980b36a28b67c..d8f3f16fe87463e140ec78fd8e6892eb989a8cba 100644 (file)
--- a/hw/net/rocker/rocker.c
+++ b/hw/net/rocker/rocker.c
@@ -1010,7 +1010,7 @@ static uint64_t rocker_port_phys_link_status(Rocker *r)
         FpPort *port = r->fp_port[i];
 
         if (fp_port_get_link_up(port)) {
-            status |= 1 << (i + 1);
+            status |= 1ULL << (i + 1);
         }
     }
     return status;
@@ -1025,7 +1025,7 @@ static uint64_t rocker_port_phys_enable_read(Rocker *r)
         FpPort *port = r->fp_port[i];
 
         if (fp_port_enabled(port)) {
-            ret |= 1 << (i + 1);
+            ret |= 1ULL << (i + 1);
         }
     }
     return ret;