RDMA/rtrs-clt: Validate peer-supplied IO completion msg_id

process_io_rsp() indexes clt_path->reqs[] with the 19-bit msg_id
taken from a WRITE_WITH_IMM immediate. That value is chosen by the
peer. The only check was WARN_ON(msg_id >= queue_depth), which still
lets a completion run after free_path_reqs() has set reqs to NULL,
or against a slot whose FRWR is already gone. Either path
dereferences req->mr and can GPF; KASAN reports a null-ptr-deref at
offsetof(struct rtrs_clt_io_req, mr).

Treat a missing reqs array, an out-of-range msg_id, or a req
without an MR as a protocol error and recover the connection.

Link: https://patch.msgid.link/r/20260923-rtrs-warning-inrtrs-clt-rdma-done-v1-1-0827a9a77c0b@proton.me
Reported-by: Farhad Alemi <farhad.alemi@berkeley.edu>
Closes: https://lore.kernel.org/r/CA+0ovCiJZz6O8LzsS9Dq1-JE1OE1L_OTA6Mr-WratpUE6jczHw@mail.gmail.com
Fixes: 6a98d71daea1 ("RDMA/rtrs: client: main functionality")
Signed-off-by: Quanye Yang <quanyeyang@proton.me>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

0 files changed, 0 insertions, 0 deletions