RDMA/rtrs-clt: Fix CQ pool leak when connect is interrupted

The client borrows shared CQ credits in the ADDR_RESOLVED handler via
ib_cq_pool_get(), before the peer is connected. create_cm() can return
-ERESTARTSYS from wait_event_interruptible_timeout() without destroying
the CM ID. The init_conns() and stop-and-destroy paths then call
destroy_con_cq_qp() while cq is still NULL (no PUT) and only afterwards
rdma_destroy_id().

CMA serializes the handler against rdma_destroy_id() with handler_mutex,
but that does not order the GET against destroy_con_cq_qp(). If
ADDR_RESOLVED has already passed the DESTROYING check, it can take
con_mutex, GET credits, and then lose the con to kfree. Device
unregister later hits WARN_ON(cq->cqe_used) in ib_cq_pool_cleanup().

Set a per-connection flag under con_mutex before CQ/QP teardown so a
racing ADDR_RESOLVED cannot borrow credits after teardown has begun.

Reported-by: syzbot+d396918a29afb8543e1c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d396918a29afb8543e1c
Fixes: 3b89e92c2a95 ("RDMA/rtrs: Use new shared CQ mechanism")
Signed-off-by: Quanye Yang <quanyeyang@proton.me>
Link: https://patch.msgid.link/20260830-rdma-rtrs-clt-cq-pool-leak-v1-1-b169434fd3df@proton.me
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

0 files changed, 0 insertions, 0 deletions