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From: Artemy Kovalyov <artemyko@mellanox.com>
Date: Sun, 25 Nov 2018 20:34:23 +0200
Subject: IB/mlx5: Skip non-ODP MR when handling a page fault
Patch-mainline: v4.20-rc5
Git-commit: 4d5422a309deecec906c491f8aea77593a46321d
References: bsc#1103991 FATE#326007

It is possible that we call pagefault_single_data_segment() with a MKey
that belongs to a memory region which is not on demand (i.e. pinned
pages). This can happen if, for instance, a WQE that points to multiple
MRs where some of them are ODP MRs and some are not.  In this case we
don't need to handle this MR in the ODP context besides reporting success.

Otherwise the code will call pagefault_mr() which will do to_ib_umem_odp()
on a non-ODP MR and thus access out of bounds.

Fixes: 7bdf65d411c1 ("IB/mlx5: Handle page faults")
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/mlx5/odp.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -674,6 +674,14 @@ next_mr:
 			goto srcu_unlock;
 		}
 
+		if (!mr->umem->is_odp) {
+			mlx5_ib_dbg(dev, "skipping non ODP MR (lkey=0x%06x) in page fault handler.\n",
+				    key);
+			if (bytes_mapped)
+				*bytes_mapped += bcnt;
+			goto srcu_unlock;
+		}
+
 		ret = pagefault_mr(dev, mr, io_virt, bcnt, bytes_mapped);
 		if (ret < 0)
 			goto srcu_unlock;