4.4-stable review patch. If anyone has any objections, please let me know.
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From: Leon Romanovsky leonro@mellanox.com
commit c8d3bcbfc5eab3f01cf373d039af725f3b488813 upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/infiniband/core/ucma.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -1316,7 +1316,7 @@ static ssize_t ucma_notify(struct ucma_f { struct rdma_ucm_notify cmd; struct ucma_context *ctx; - int ret; + int ret = -EINVAL;
if (copy_from_user(&cmd, inbuf, sizeof(cmd))) return -EFAULT; @@ -1325,7 +1325,9 @@ static ssize_t ucma_notify(struct ucma_f 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; }