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 0FE5518C925; Tue, 10 Sep 2024 10:14:11 +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=1725963251; cv=none; b=TY60erlJFmZiFCfFbaKCRFKc3cl/lSrJqTQzHiqKUX/xAxX7iAiaLhnM/duqX+BQnF6pH+G1bS87G5Lr5NQN7jLrHAg0HNWqQgdy0E+6SkOcj2SFwP1+SObC8hGaqjxiWes7YYCrGRGqKQCLUmQf8OT+r+pT+VPV5faaf2u96Fk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725963251; c=relaxed/simple; bh=8nav9rMnXIhF8YQT2GL3rPazRbBfkQrSyN68WNKnyrQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lw2amX28vNrjO9UhHQT1YjD4Gpw29ZeMP6q6vkf28s29oPJe+clAcOQkYg4FFal2UmWMX31cDVJZapYGpxPoPkuWBlkPNXumUq5g7eny5JWNo7qyyRsi4QtnVQ7FuyUuKtNo/y+2Xp6qJQRkCXg1T+Y9h3xkJ14QYfQ9pRjcxEw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qRzg4srn; 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="qRzg4srn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 87431C4CECD; Tue, 10 Sep 2024 10:14:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725963250; bh=8nav9rMnXIhF8YQT2GL3rPazRbBfkQrSyN68WNKnyrQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qRzg4srnD0ZHKEZbYLC+KDe+1tex/SXD7e7BMLFpTa3o/R2N/qpFSzqkJxGdc6nXR jqwKir6Dat9ASTqsDGTUola1BxhjEIuIHuoGgO1Vi+As29mnRGxxcg8GDBRBnArrMs vhitlks0F4/ftgHaWuxeZ1eIccuqELKGg0eShjNk= 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 6.1 186/192] ublk_drv: fix NULL pointer dereference in ublk_ctrl_start_recovery() Date: Tue, 10 Sep 2024 11:33:30 +0200 Message-ID: <20240910092605.464064948@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240910092557.876094467@linuxfoundation.org> References: <20240910092557.876094467@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 6.1-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 3fa74051f31b..bfd643856f64 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -1915,6 +1915,8 @@ 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