RDMA/amso1100: Check for integer overflow in c2_alloc_cq_buf()

This is a static checker fix.  The static checker says that q_size comes
from the user and can be any 32 bit value.  The call tree is:
  --> ib_uverbs_create_cq()
      --> c2_create_cq()
          --> c2_init_cq()

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/infiniband/hw/amso1100/c2_cq.c b/drivers/infiniband/hw/amso1100/c2_cq.c
index 49e0e8533f74..1b63185b4ad4 100644
--- a/drivers/infiniband/hw/amso1100/c2_cq.c
+++ b/drivers/infiniband/hw/amso1100/c2_cq.c
@@ -260,11 +260,14 @@ static void c2_free_cq_buf(struct c2_dev *c2dev, struct c2_mq *mq)
                           mq->msg_pool.host, dma_unmap_addr(mq, mapping));
 }
 
-static int c2_alloc_cq_buf(struct c2_dev *c2dev, struct c2_mq *mq, int q_size,
-                           int msg_size)
+static int c2_alloc_cq_buf(struct c2_dev *c2dev, struct c2_mq *mq,
+                           size_t q_size, size_t msg_size)
 {
         u8 *pool_start;
 
+        if (q_size > SIZE_MAX / msg_size)
+                return -EINVAL;
+
         pool_start = dma_alloc_coherent(&c2dev->pcidev->dev, q_size * msg_size,
                                         &mq->host_dma, GFP_KERNEL);
         if (!pool_start)