RDMA/irdma: Prevent zero-length STAG registration

Currently irdma allows zero-length STAGs to be programmed in HW during
the kernel mode fast register flow. Zero-length MR or STAG registration
disable HW memory length checks.

Improve gaps in bounds checking in irdma by preventing zero-length STAG or
MR registrations except if the IB_PD_UNSAFE_GLOBAL_RKEY is set.

This addresses the disclosure CVE-2023-25775.

Fixes: b48c24c ("RDMA/irdma: Implement device supported verb APIs")
Signed-off-by: Christopher Bednarz <christopher.n.bednarz@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Link: https://lore.kernel.org/r/20230818144838.1758-1-shiraz.saleem@intel.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

Author: cnbednar

drivers/infiniband/hw/irdma/ctrl.c

@@ -1061,6 +1061,9 @@ static int irdma_sc_alloc_stag(struct irdma_sc_dev *dev,
 	u64 hdr;
 	enum irdma_page_size page_size;
 
+	if (!info->total_len && !info->all_memory)
+		return -EINVAL;
+
 	if (info->page_size == 0x40000000)
 		page_size = IRDMA_PAGE_SIZE_1G;
 	else if (info->page_size == 0x200000)
@@ -1126,6 +1129,9 @@ static int irdma_sc_mr_reg_non_shared(struct irdma_sc_dev *dev,
 	u8 addr_type;
 	enum irdma_page_size page_size;
 
+	if (!info->total_len && !info->all_memory)
+		return -EINVAL;
+
 	if (info->page_size == 0x40000000)
 		page_size = IRDMA_PAGE_SIZE_1G;
 	else if (info->page_size == 0x200000)

drivers/infiniband/hw/irdma/type.h

@@ -969,6 +969,7 @@ struct irdma_allocate_stag_info {
 	bool remote_access:1;
 	bool use_hmc_fcn_index:1;
 	bool use_pf_rid:1;
+	bool all_memory:1;
 	u8 hmc_fcn_index;
 };
 
@@ -996,6 +997,7 @@ struct irdma_reg_ns_stag_info {
 	bool use_hmc_fcn_index:1;
 	u8 hmc_fcn_index;
 	bool use_pf_rid:1;
+	bool all_memory:1;
 };
 
 struct irdma_fast_reg_stag_info {

drivers/infiniband/hw/irdma/verbs.c

@@ -2624,7 +2624,8 @@ static int irdma_hw_alloc_stag(struct irdma_device *iwdev,
 			       struct irdma_mr *iwmr)
 {
 	struct irdma_allocate_stag_info *info;
-	struct irdma_pd *iwpd = to_iwpd(iwmr->ibmr.pd);
+	struct ib_pd *pd = iwmr->ibmr.pd;
+	struct irdma_pd *iwpd = to_iwpd(pd);
 	int status;
 	struct irdma_cqp_request *cqp_request;
 	struct cqp_cmds_info *cqp_info;
@@ -2640,6 +2641,7 @@ static int irdma_hw_alloc_stag(struct irdma_device *iwdev,
 	info->stag_idx = iwmr->stag >> IRDMA_CQPSQ_STAG_IDX_S;
 	info->pd_id = iwpd->sc_pd.pd_id;
 	info->total_len = iwmr->len;
+	info->all_memory = pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY;
 	info->remote_access = true;
 	cqp_info->cqp_cmd = IRDMA_OP_ALLOC_STAG;
 	cqp_info->post_sq = 1;
@@ -2687,6 +2689,8 @@ static struct ib_mr *irdma_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
 	iwmr->type = IRDMA_MEMREG_TYPE_MEM;
 	palloc = &iwpbl->pble_alloc;
 	iwmr->page_cnt = max_num_sg;
+	/* Use system PAGE_SIZE as the sg page sizes are unknown at this point */
+	iwmr->len = max_num_sg * PAGE_SIZE;
 	err_code = irdma_get_pble(iwdev->rf->pble_rsrc, palloc, iwmr->page_cnt,
 				  false);
 	if (err_code)
@@ -2766,7 +2770,8 @@ static int irdma_hwreg_mr(struct irdma_device *iwdev, struct irdma_mr *iwmr,
 {
 	struct irdma_pbl *iwpbl = &iwmr->iwpbl;
 	struct irdma_reg_ns_stag_info *stag_info;
-	struct irdma_pd *iwpd = to_iwpd(iwmr->ibmr.pd);
+	struct ib_pd *pd = iwmr->ibmr.pd;
+	struct irdma_pd *iwpd = to_iwpd(pd);
 	struct irdma_pble_alloc *palloc = &iwpbl->pble_alloc;
 	struct irdma_cqp_request *cqp_request;
 	struct cqp_cmds_info *cqp_info;
@@ -2785,6 +2790,7 @@ static int irdma_hwreg_mr(struct irdma_device *iwdev, struct irdma_mr *iwmr,
 	stag_info->total_len = iwmr->len;
 	stag_info->access_rights = irdma_get_mr_access(access);
 	stag_info->pd_id = iwpd->sc_pd.pd_id;
+	stag_info->all_memory = pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY;
 	if (stag_info->access_rights & IRDMA_ACCESS_FLAGS_ZERO_BASED)
 		stag_info->addr_type = IRDMA_ADDR_TYPE_ZERO_BASED;
 	else