nvmet-tcp: check INIT_FAILED before nvmet_req_uninit in digest error path

commit 4606467a75 upstream.

In nvmet_tcp_try_recv_ddgst(), when a data digest mismatch is detected,
nvmet_req_uninit() is called unconditionally. However, if the command
arrived via the nvmet_tcp_handle_req_failure() path, nvmet_req_init()
had returned false and percpu_ref_tryget_live() was never executed. The
unconditional percpu_ref_put() inside nvmet_req_uninit() then causes a
refcount underflow, leading to a WARNING in
percpu_ref_switch_to_atomic_rcu, a use-after-free diagnostic, and
eventually a permanent workqueue deadlock.

Check cmd->flags & NVMET_TCP_F_INIT_FAILED before calling
nvmet_req_uninit(), matching the existing pattern in
nvmet_tcp_execute_request().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Shivam Kumar <kumar.shivam43666@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Shivam Kumar
2026-07-24 16:02:56 +02:00
committed by Greg Kroah-Hartman
parent 477145860d
commit e602c93b25
+2 -1
View File
@@ -1297,7 +1297,8 @@ static int nvmet_tcp_try_recv_ddgst(struct nvmet_tcp_queue *queue)
queue->idx, cmd->req.cmd->common.command_id,
queue->pdu.cmd.hdr.type, le32_to_cpu(cmd->recv_ddgst),
le32_to_cpu(cmd->exp_ddgst));
nvmet_req_uninit(&cmd->req);
if (!(cmd->flags & NVMET_TCP_F_INIT_FAILED))
nvmet_req_uninit(&cmd->req);
nvmet_tcp_free_cmd_buffers(cmd);
nvmet_tcp_fatal_error(queue);
ret = -EPROTO;