From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59D22C433FE for ; Tue, 1 Nov 2022 11:32:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230386AbiKALcl (ORCPT ); Tue, 1 Nov 2022 07:32:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230405AbiKALbU (ORCPT ); Tue, 1 Nov 2022 07:31:20 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 787F91AF18; Tue, 1 Nov 2022 04:29:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8F642615C9; Tue, 1 Nov 2022 11:29:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 073E5C433C1; Tue, 1 Nov 2022 11:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667302196; bh=USvHquiFgiGFjM0GueEZoVxriggjzHuSZ+R9lifCgAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JEB1T0vqmUHgQr25VCGigz9sZypwcFhAVX37cb68ezyvH9RV1PRJDz3/UddlYFtXA yLGH04Fphei+pMV/SevgDFvppRxprgnKP3n98BhWX4I3b0cwkUDCzamV8JAL4X4mk+ VlDRELQqfv0gOKmOQ/xqMH+pdwzd+FFxAK9amkz8+lFZicyJiSjwIsJxfYvgi4BwTT 8fHDENw/YiPoWTQF7ukh5Sfq3vhRD7DiLMj5SolHRMM1u4nsW4Brc7xQaumxR000jw ow32810GG22ub50Is17aXRG9b8Re7pEq3nuLI8HJv8VeXyJPb+Mwd+GVUU6pdYdGH5 QsJUeRmZg+FdA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Uday Shankar , Mike Christie , Hannes Reinecke , "Martin K . Petersen" , Sasha Levin , jejb@linux.ibm.com, linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 15/19] scsi: core: Restrict legal sdev_state transitions via sysfs Date: Tue, 1 Nov 2022 07:29:15 -0400 Message-Id: <20221101112919.799868-15-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221101112919.799868-1-sashal@kernel.org> References: <20221101112919.799868-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Uday Shankar [ Upstream commit 2331ce6126be8864b39490e705286b66e2344aac ] Userspace can currently write to sysfs to transition sdev_state to RUNNING or OFFLINE from any source state. This causes issues because proper transitioning out of some states involves steps besides just changing sdev_state, so allowing userspace to change sdev_state regardless of the source state can result in inconsistencies; e.g. with ISCSI we can end up with sdev_state == SDEV_RUNNING while the device queue is quiesced. Any task attempting I/O on the device will then hang, and in more recent kernels, iscsid will hang as well. More detail about this bug is provided in my first attempt: https://groups.google.com/g/open-iscsi/c/PNKca4HgPDs/m/CXaDkntOAQAJ Link: https://lore.kernel.org/r/20220924000241.2967323-1-ushankar@purestorage.com Signed-off-by: Uday Shankar Suggested-by: Mike Christie Reviewed-by: Hannes Reinecke Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/scsi_sysfs.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 920aae661c5b..774864b54b97 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -816,6 +816,14 @@ store_state_field(struct device *dev, struct device_attribute *attr, } mutex_lock(&sdev->state_mutex); + switch (sdev->sdev_state) { + case SDEV_RUNNING: + case SDEV_OFFLINE: + break; + default: + mutex_unlock(&sdev->state_mutex); + return -EINVAL; + } if (sdev->sdev_state == SDEV_RUNNING && state == SDEV_RUNNING) { ret = 0; } else { -- 2.35.1