RDMA/uverbs: Restrict usage of privileged QKEYs

According to the IB specification rel-1.6, section 3.5.3:
"QKEYs with the most significant bit set are considered controlled
QKEYs, and a HCA does not allow a consumer to arbitrarily specify a
controlled QKEY."

Thus, block non-privileged users from setting such a QKEY.

Cc: stable@vger.kernel.org
Fixes: bc38a6abdd5a ("[PATCH] IB uverbs: core implementation")
Signed-off-by: Edward Srouji <edwards@nvidia.com>
Link: https://lore.kernel.org/r/c00c809ddafaaf87d6f6cb827978670989a511b3.1685960567.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 4796f6a..e836c9c 100644 (file)
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1850,8 +1850,13 @@ static int modify_qp(struct uverbs_attr_bundle *attrs,
                attr->path_mtu = cmd->base.path_mtu;
        if (cmd->base.attr_mask & IB_QP_PATH_MIG_STATE)
                attr->path_mig_state = cmd->base.path_mig_state;
-       if (cmd->base.attr_mask & IB_QP_QKEY)
+       if (cmd->base.attr_mask & IB_QP_QKEY) {
+               if (cmd->base.qkey & IB_QP_SET_QKEY && !capable(CAP_NET_RAW)) {
+                       ret = -EPERM;
+                       goto release_qp;
+               }
                attr->qkey = cmd->base.qkey;
+       }
        if (cmd->base.attr_mask & IB_QP_RQ_PSN)
                attr->rq_psn = cmd->base.rq_psn;
        if (cmd->base.attr_mask & IB_QP_SQ_PSN)