From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 59765606A330 for ; Mon, 9 Nov 2026 02:27:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=etnoOD3M; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.a=rsa-sha256 header.s=default header.b=Rsq/m1/Z DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=u1ipky8YJM+eoKIymd4Uk2gvs400AQ3YsUr4XSGDwEE=; b=etnoOD3MCRpZ5N iQvqXqLUrzb75uXNPHbrnIckNn6MCPQQWgCexC1AbYeSBsB512yLM/4ZFPxmTbLY76TeEoO5OlIHQ E/VpGVncF5SYtZ7+frnSN6xZMdZQL7WTbmnlm+jF9efE9Q+4e01R1TNxAZXASr+NCt67qwpDIe2SJ bWrzKqd2EoOIEmchP+W0xQuMt0e+rrUAI0sAckaztIrF6VEv8BkbdN+OVGnWqKGNLke8UdFwVwg4O fxUEX8nRzGjUXPoQre/uKqrarLJHYbNXvqDnoxnfVpSBFLxQW65om01ItTD0VlngkwF84o0FXKEq+ WO7EAi4A37oZLHpPWFGA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xQF67-0000000H7fs-48DV; Mon, 09 Nov 2026 02:27:04 +0000 Received: from out30-131.freemail.mail.aliyun.com ([115.124.30.131]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xQF64-0000000H7d3-1fsa for linux-nvme@lists.infradead.org; Mon, 09 Nov 2026 02:27:02 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1794191214; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=u1ipky8YJM+eoKIymd4Uk2gvs400AQ3YsUr4XSGDwEE=; b=Rsq/m1/ZpoDuQz6UWxlB6FxRbl2xkN2mNDe1Unj2VolA5WlOfXwid+bijTZ1L5kmgbZCiwmTzco41LOZKOcFDz/SF7AvcrTqTDSsR/ACJwCW1OwfzMW5QMKvoFN66DbmRzrHGr02cnMY2p36L5xkvggPPy/+eMSd5gToTITqUAc= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033032089153;MF=kanie@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0XEIBGfS_1794191212; Received: from localhost(mailfrom:kanie@linux.alibaba.com fp:SMTPD_---0XEIBGfS_1794191212 cluster:ay36) by smtp.aliyun-inc.com; Mon, 09 Nov 2026 10:26:52 +0800 From: Guixin Liu To: Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , Nilay Shroff , Daniel Wagner , Hannes Reinecke Cc: linux-nvme@lists.infradead.org Subject: [PATCH v2 1/5] nvme: reject a reconnect_delay of 0 through sysfs Date: Mon, 9 Nov 2026 10:26:42 +0800 Message-ID: <20261109022646.290792-2-kanie@linux.alibaba.com> X-Mailer: git-send-email 2.43.7 In-Reply-To: <20261109022646.290792-1-kanie@linux.alibaba.com> References: <20261109022646.290792-1-kanie@linux.alibaba.com> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261108_182700_778469_4D56AD66 X-CRM114-Status: GOOD ( 11.68 ) X-Spam-Score: -17.6 (-----------------) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" X-Spam-Status: No, score=-26.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 nvme_ctrl_reconnect_delay_store() accepts any value the option parser also accepts, except that it misses the lower bound: writing 0 is rejected by nvmf_parse_options() but not by the sysfs attribute. nvme_ctrl_loss_tmo_store() then divides by opts->reconnect_delay in DIV_ROUND_UP(), so writing 0 followed by any ctrl_loss_tmo update crashes the kernel with a division by zero. Reject 0 like the option parser does. Fixes: 764075fdcb2f ("nvme: expose reconnect_delay and ctrl_loss_tmo via sysfs") Cc: stable@vger.kernel.org Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Reviewed-by: Nilay Shroff Signed-off-by: Guixin Liu --- Reproduced on an unfixed 7.3.0-rc7 kernel in a VM with a fabrics controller connected: echo 0 > /sys/class/nvme/nvme1/reconnect_delay echo 30 > /sys/class/nvme/nvme1/ctrl_loss_tmo Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 7 UID: 0 PID: 1542 Comm: bash Not tainted 7.3.0-rc7 RIP: 0010:nvme_ctrl_loss_tmo_store+0xce/0x120 [nvme_core] Code: ... 8d 44 08 ff f1 ... RAX: 000000000000001d RCX: 0000000000000000 Verified on the patched kernel: writing 0 returns -EINVAL and the ctrl_loss_tmo update succeeds without an oops. --- drivers/nvme/host/sysfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/nvme/host/sysfs.c b/drivers/nvme/host/sysfs.c index 10018c6356b6..bae0d6258d01 100644 --- a/drivers/nvme/host/sysfs.c +++ b/drivers/nvme/host/sysfs.c @@ -634,6 +634,9 @@ static ssize_t nvme_ctrl_reconnect_delay_store(struct device *dev, if (err) return err; + if (!v) + return -EINVAL; + ctrl->opts->reconnect_delay = v; return count; } -- 2.43.7