From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 34EE0190664; Tue, 10 Sep 2024 10:37:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725964674; cv=none; b=SPvIfdeLz7igifBl8zoQeOvwEof+JOqLBPQLJSDRa222TbD+FUvoV+bjVTrO2WuqLmNxgC5cE8FvyEvCeF3tZD0flpywOvkPsiMThDXXrKPA6MKRGCN0nqLOh0K1o/1XznGvyH6EsBnYkF2UL/IS9oMIVPWXn5derdP9taoefQE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725964674; c=relaxed/simple; bh=8kLRZsSFb/VNXidY6Jcz7BQkeGDUDK+gh7iyv5PkoG8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gPaAH3IMchl53ScuCzuzIDve77+uRBxv0Fh/0Nb6Els4/pHEokTXc5wtkPYqTjXUugs9fH4UXw6F/NcI2C0W0MnW6yKPp7E3Cl51dyyy3Eoebdg4PcXtBBgNtM3kmROHU4FZ8ZTokKAHzgezeunDCLdnDM1aav0uqYF5WBO3twg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Z3eVi5Xb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Z3eVi5Xb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1595C4CEC3; Tue, 10 Sep 2024 10:37:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725964674; bh=8kLRZsSFb/VNXidY6Jcz7BQkeGDUDK+gh7iyv5PkoG8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z3eVi5XbzKECfGjgVoeD6HHYEfLcBAetv3m49nrjGHPo6jT3b2Dta8q2eqPESwkWj q5zfiMaF5b5h0AGoR1tyLnj4ZgGla3IKp6dc3tsE0ptW6WV6TigHzAYhQ/IOKQppim lNalETY9OQ/ivbIIiRIFmI3n6d+E12BJyWNNMwYc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ming Lei , Li Nan , Jens Axboe , Sasha Levin , Changhui Zhong Subject: [PATCH 6.6 262/269] ublk_drv: fix NULL pointer dereference in ublk_ctrl_start_recovery() Date: Tue, 10 Sep 2024 11:34:09 +0200 Message-ID: <20240910092617.095885029@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240910092608.225137854@linuxfoundation.org> References: <20240910092608.225137854@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Li Nan [ Upstream commit e58f5142f88320a5b1449f96a146f2f24615c5c7 ] When two UBLK_CMD_START_USER_RECOVERY commands are submitted, the first one sets 'ubq->ubq_daemon' to NULL, and the second one triggers WARN in ublk_queue_reinit() and subsequently a NULL pointer dereference issue. Fix it by adding the check in ublk_ctrl_start_recovery() and return immediately in case of zero 'ub->nr_queues_ready'. BUG: kernel NULL pointer dereference, address: 0000000000000028 RIP: 0010:ublk_ctrl_start_recovery.constprop.0+0x82/0x180 Call Trace: ? __die+0x20/0x70 ? page_fault_oops+0x75/0x170 ? exc_page_fault+0x64/0x140 ? asm_exc_page_fault+0x22/0x30 ? ublk_ctrl_start_recovery.constprop.0+0x82/0x180 ublk_ctrl_uring_cmd+0x4f7/0x6c0 ? pick_next_task_idle+0x26/0x40 io_uring_cmd+0x9a/0x1b0 io_issue_sqe+0x193/0x3f0 io_wq_submit_work+0x9b/0x390 io_worker_handle_work+0x165/0x360 io_wq_worker+0xcb/0x2f0 ? finish_task_switch.isra.0+0x203/0x290 ? finish_task_switch.isra.0+0x203/0x290 ? __pfx_io_wq_worker+0x10/0x10 ret_from_fork+0x2d/0x50 ? __pfx_io_wq_worker+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Fixes: c732a852b419 ("ublk_drv: add START_USER_RECOVERY and END_USER_RECOVERY support") Reported-and-tested-by: Changhui Zhong Closes: https://lore.kernel.org/all/CAGVVp+UvLiS+bhNXV-h2icwX1dyybbYHeQUuH7RYqUvMQf6N3w@mail.gmail.com Reviewed-by: Ming Lei Signed-off-by: Li Nan Link: https://lore.kernel.org/r/20240904031348.4139545-1-ming.lei@redhat.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/block/ublk_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index f4e0573c4711..bf7f68e90953 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -2603,6 +2603,8 @@ static int ublk_ctrl_start_recovery(struct ublk_device *ub, mutex_lock(&ub->mutex); if (!ublk_can_use_recovery(ub)) goto out_unlock; + if (!ub->nr_queues_ready) + goto out_unlock; /* * START_RECOVERY is only allowd after: * -- 2.43.0