RDMA/ucma: Check that device exists prior to accessing it
Ensure that device exists prior to accessing its properties.
Reported-by: <syzbot+71655d44855ac3e76366@syzkaller.appspotmail.com>
Fixes: 75216638572f ("RDMA/cma: Export rdma cm interface to userspace")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index 0811f58..2158505 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -1336,7 +1336,7 @@ static ssize_t ucma_notify(struct ucma_file *file, const char __user *inbuf,
{
struct rdma_ucm_notify cmd;
struct ucma_context *ctx;
- int ret;
+ int ret = -EINVAL;
if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
return -EFAULT;
@@ -1345,7 +1345,9 @@ static ssize_t ucma_notify(struct ucma_file *file, const char __user *inbuf,
if (IS_ERR(ctx))
return PTR_ERR(ctx);
- ret = rdma_notify(ctx->cm_id, (enum ib_event_type) cmd.event);
+ if (ctx->cm_id->device)
+ ret = rdma_notify(ctx->cm_id, (enum ib_event_type)cmd.event);
+
ucma_put_ctx(ctx);
return ret;
}