[PATCH 3.2 118/153] RDMA/ucma: Check that user doesn't overflow QP state

[Ben Hutchings]

3.2.102-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Leon Romanovsky <leonro@xxxxxxxxxxxx>

commit a5880b84430316e3e1c1f5d23aa32ec6000cc717 upstream.

The QP state is limited and declared in enum ib_qp_state,
but ucma user was able to supply any possible (u32) value.

Reported-by: syzbot+0df1ab766f8924b1edba@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 75216638572f ("RDMA/cma: Export rdma cm interface to userspace")
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/infiniband/core/ucma.c | 3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -873,6 +873,9 @@ static ssize_t ucma_init_qp_attr(struct
 	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 		return -EFAULT;
 
+	if (cmd.qp_state > IB_QPS_ERR)
+		return -EINVAL;
+
 	ctx = ucma_get_ctx(file, cmd.id);
 	if (IS_ERR(ctx))
 		return PTR_ERR(ctx);