Re: [PATCH] nbd: defer config put in recv_work

From: Jens Axboe
Date: Sat Nov 08 2025 - 08:40:30 EST



On Sat, 08 Nov 2025 15:02:02 +0800, Zheng Qixing wrote:
> There is one uaf issue in recv_work when running NBD_CLEAR_SOCK and
> NBD_CMD_RECONFIGURE:
> nbd_genl_connect // conf_ref=2 (connect and recv_work A)
> nbd_open // conf_ref=3
> recv_work A done // conf_ref=2
> NBD_CLEAR_SOCK // conf_ref=1
> nbd_genl_reconfigure // conf_ref=2 (trigger recv_work B)
> close nbd // conf_ref=1
> recv_work B
> config_put // conf_ref=0
> atomic_dec(&config->recv_threads); -> UAF
>
> [...]

Applied, thanks!

[1/1] nbd: defer config put in recv_work
commit: 9517b82d8d422d426a988b213fdd45c6b417b86d

Best regards,
--
Jens Axboe