RDMA/irdma: Check contents of user-space irdma_mem_reg_req object

The contents of user-space req object is used in array indexing in
irdma_handle_q_mem without checking for valid values.

Guard against bad input on each of these req object pages by limiting them
to number of pages that make up the region.

Link: https://lore.kernel.org/r/20210625162329.1654-2-tatyana.e.nikolova@intel.comReported-by: Ncoverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1505160 ("TAINTED_SCALAR")
Fixes: b48c24c2 ("RDMA/irdma: Implement device supported verb APIs")
Signed-off-by: NShiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: NTatyana Nikolova <tatyana.e.nikolova@intel.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/irdma/verbs.c

@@ -2358,12 +2358,10 @@ static int irdma_handle_q_mem(struct irdma_device *iwdev,
 	struct irdma_cq_mr *cqmr = &iwpbl->cq_mr;
 	struct irdma_hmc_pble *hmc_p;
 	u64 *arr = iwmr->pgaddrmem;
-	u32 pg_size;
+	u32 pg_size, total;
 	int err = 0;
-	int total;
 	bool ret = true;
 
-	total = req->sq_pages + req->rq_pages + req->cq_pages;
 	pg_size = iwmr->page_size;
 	err = irdma_setup_pbles(iwdev->rf, iwmr, use_pbles);
 	if (err)
@@ -2380,6 +2378,7 @@ static int irdma_handle_q_mem(struct irdma_device *iwdev,
 
 	switch (iwmr->type) {
 	case IRDMA_MEMREG_TYPE_QP:
+		total = req->sq_pages + req->rq_pages;
 		hmc_p = &qpmr->sq_pbl;
 		qpmr->shadow = (dma_addr_t)arr[total];
 
@@ -2406,7 +2405,7 @@ static int irdma_handle_q_mem(struct irdma_device *iwdev,
 		hmc_p = &cqmr->cq_pbl;
 
 		if (!cqmr->split)
-			cqmr->shadow = (dma_addr_t)arr[total];
+			cqmr->shadow = (dma_addr_t)arr[req->cq_pages];
 
 		if (use_pbles)
 			ret = irdma_check_mem_contiguous(arr, req->cq_pages,
@@ -2747,7 +2746,8 @@ static struct ib_mr *irdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 len,
 	struct irdma_mr *iwmr;
 	struct ib_umem *region;
 	struct irdma_mem_reg_req req;
-	u32 stag = 0;
+	u32 total, stag = 0;
+	u8 shadow_pgcnt = 1;
 	bool use_pbles = false;
 	unsigned long flags;
 	int err = -EINVAL;
@@ -2801,7 +2801,13 @@ static struct ib_mr *irdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 len,
 
 	switch (req.reg_type) {
 	case IRDMA_MEMREG_TYPE_QP:
-		use_pbles = ((req.sq_pages + req.rq_pages) > 2);
+		total = req.sq_pages + req.rq_pages + shadow_pgcnt;
+		if (total > iwmr->page_cnt) {
+			err = -EINVAL;
+			goto error;
+		}
+		total = req.sq_pages + req.rq_pages;
+		use_pbles = (total > 2);
 		err = irdma_handle_q_mem(iwdev, &req, iwpbl, use_pbles);
 		if (err)
 			goto error;
@@ -2814,6 +2820,14 @@ static struct ib_mr *irdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 len,
 		spin_unlock_irqrestore(&ucontext->qp_reg_mem_list_lock, flags);
 		break;
 	case IRDMA_MEMREG_TYPE_CQ:
+		if (iwdev->rf->sc_dev.hw_attrs.uk_attrs.feature_flags & IRDMA_FEATURE_CQ_RESIZE)
+			shadow_pgcnt = 0;
+		total = req.cq_pages + shadow_pgcnt;
+		if (total > iwmr->page_cnt) {
+			err = -EINVAL;
+			goto error;
+		}
+
 		use_pbles = (req.cq_pages > 1);
 		err = irdma_handle_q_mem(iwdev, &req, iwpbl, use_pbles);
 		if (err)