[PATCH 1/2] hw/block/nvme: fix potential overflow

[Klaus Jensen]

From: Klaus Jensen <k.jensen@samsung.com>

page_size is a uint32_t, and zasl is a uint8_t, so the expression
`page_size << zasl` is done using 32-bit arithmetic and might overflow.
Since we then compare this against a 64 bit data_size value, Coverity
complains that we might overflow unintentionally. An MDTS/ZASL value in
excess of 4GiB is probably impractical, but it is not entirely
unrealistic, so add a cast such that we handle that case properly.

Fixes: 578d914b263c ("hw/block/nvme: align zoned.zasl with mdts")
Fixes: CID 1450756
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 hw/block/nvme.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index d439e44db839..f8ad34077000 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -2188,7 +2188,7 @@ static uint16_t nvme_do_write(NvmeCtrl *n, NvmeRequest 
*req, bool append,
                 goto invalid;
             }
 
-            if (n->params.zasl && data_size > n->page_size << n->params.zasl) {
+            if (n->params.zasl && data_size > (uint64_t)n->page_size << 
n->params.zasl) {
                 trace_pci_nvme_err_zasl(data_size);
                 return NVME_INVALID_FIELD | NVME_DNR;
             }
-- 
2.30.1