[patch -next] qed: potential overflow in qed_cxt_src_t2_alloc()

[Dan Carpenter <dan.carpenter@oracle.com>]

In the current code "ent_per_page" could be more than "conn_num" making
"conn_num" negative after the subtraction.  In the next iteration
through the loop then the negative is treated as a very high positive
meaning we don't put a limit on "ent_num".  It could lead to memory
corruption.

Fixes: dbb799c39717 ('qed: Initialize hardware for new protocols')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/net/ethernet/qlogic/qed/qed_cxt.c b/drivers/net/ethernet/qlogic/qed/qed_cxt.c
index d85b7ba..1c35f37 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_cxt.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_cxt.c
@@ -850,7 +850,7 @@ static int qed_cxt_src_t2_alloc(struct qed_hwfn *p_hwfn)
 			val = 0;
 		entries[j].next = cpu_to_be64(val);
 
-		conn_num -= ent_per_page;
+		conn_num -= ent_num;
 	}
 
 	return 0;