tree 2dd5eb3eabf24c6a922a8649c6acf9e9e5410c26
parent 9ea04d0df6e6541c6736b43bff45f1e54875a1db
author Leon Romanovsky <leonro@mellanox.com> 1581492395 +0200
committer Jason Gunthorpe <jgg@mellanox.com> 1581604763 -0400

RDMA/mlx5: Prevent overflow in mmap offset calculations

The cmd and index variables declared as u16 and the result is supposed to
be stored in u64. The C arithmetic rules doesn't promote "(index >> 8) <<
16" to be u64 and leaves the end result to be u16.

Fixes: 7be76bef320b ("IB/mlx5: Introduce VAR object and its alloc/destroy methods")
Link: https://lore.kernel.org/r/20200212072635.682689-10-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>