[PATCH v2 09/12] hw/mem/cxl_type3: Fix potential divide by zero reported by coverity

Jonathan Cameron via posted 12 patches 10 months ago
Maintainers: Jonathan Cameron <jonathan.cameron@huawei.com>, Fan Ni <fan.ni@samsung.com>, "Michael S. Tsirkin" <mst@redhat.com>, Igor Mammedov <imammedo@redhat.com>, Ani Sinha <anisinha@redhat.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Eduardo Habkost <eduardo@habkost.net>
[PATCH v2 09/12] hw/mem/cxl_type3: Fix potential divide by zero reported by coverity
Posted by Jonathan Cameron via 10 months ago
Fixes Coverity ID 1522368.

Currently error_fatal is set if interleave_ways_dec() is going to return 0
but we should handle that zero return explicitly.

Reported-by: Stefan Hajnoczi <stefanha@gmail.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

---
Note this is a stop gap until a more complex HDM decoder verification series.
---
 hw/mem/cxl_type3.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index 1b92a065a3..71fcb44613 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -794,8 +794,13 @@ static bool cxl_type3_dpa(CXLType3Dev *ct3d, hwaddr host_addr, uint64_t *dpa)
         }
         if (((uint64_t)host_addr < decoder_base) ||
             (hpa_offset >= decoder_size)) {
-            dpa_base += decoder_size /
-                cxl_interleave_ways_dec(iw, &error_fatal);
+            int decoded_iw = cxl_interleave_ways_dec(iw, &error_fatal);
+
+            if (decoded_iw == 0) {
+                return false;
+            }
+
+            dpa_base += decoder_size / decoded_iw;
             continue;
         }
 
-- 
2.39.2