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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0F0DC0650F for ; Thu, 8 Aug 2019 19:14:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7A1C214C6 for ; Thu, 8 Aug 2019 19:14:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565291646; bh=rxiTNpmN3JfowyIDYyku5rB8rgfj5MmDvzXltVZD1vU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MuRHi8TRJcngOQThTGdXVbFvkm8pzPHBcVKhS2Vw98fUFakS0hDgf4nlLvw+v7VC+ 0BBtRAU04M4+Hcm29xqmqwOoNBi9QEkgoyMPzKiwXlwM4owtonTFyhIER6tJAV5bVA 2CZ4GJzl8tTD/Z3UNpIo0WoQbtVONqcjfWzaHNOk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405164AbfHHTOF (ORCPT ); Thu, 8 Aug 2019 15:14:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:43184 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405007AbfHHTI5 (ORCPT ); Thu, 8 Aug 2019 15:08:57 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 13881214C6; Thu, 8 Aug 2019 19:08:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565291336; bh=rxiTNpmN3JfowyIDYyku5rB8rgfj5MmDvzXltVZD1vU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yy58jnSV+W267cOjRACNfs6Q2J+iAbIsacloXvVjac6zm96hi3Ed1Gc3BOws5jXS6 CFz4g6v//s2J/7vkOXMCeRS35N/YGYA+x7bYjxLBG2l4EWk1lVHCcH0PpeLM2VtPvw jZnsFm+AnshGoUSCtYTsx/34/ZF1om8kqINm1h+0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vishal Verma , Dan Williams , Sasha Levin Subject: [PATCH 4.19 07/45] libnvdimm/bus: Prepare the nd_ioctl() path to be re-entrant Date: Thu, 8 Aug 2019 21:04:53 +0200 Message-Id: <20190808190454.189996943@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190808190453.827571908@linuxfoundation.org> References: <20190808190453.827571908@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org commit 6de5d06e657acdbcf9637dac37916a4a5309e0f4 upstream. In preparation for not holding a lock over the execution of nd_ioctl(), update the implementation to allow multiple threads to be attempting ioctls at the same time. The bus lock still prevents multiple in-flight ->ndctl() invocations from corrupting each other's state, but static global staging buffers are moved to the heap. Reported-by: Vishal Verma Reviewed-by: Vishal Verma Tested-by: Vishal Verma Link: https://lore.kernel.org/r/156341208947.292348.10560140326807607481.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Sasha Levin --- drivers/nvdimm/bus.c | 59 +++++++++++++++++++++++++++----------------- 1 file changed, 37 insertions(+), 22 deletions(-) diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c index 11cfd23e5aff7..5abcdb4faa644 100644 --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -951,20 +951,19 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, int read_only, unsigned int ioctl_cmd, unsigned long arg) { struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; - static char out_env[ND_CMD_MAX_ENVELOPE]; - static char in_env[ND_CMD_MAX_ENVELOPE]; const struct nd_cmd_desc *desc = NULL; unsigned int cmd = _IOC_NR(ioctl_cmd); struct device *dev = &nvdimm_bus->dev; void __user *p = (void __user *) arg; + char *out_env = NULL, *in_env = NULL; const char *cmd_name, *dimm_name; u32 in_len = 0, out_len = 0; unsigned int func = cmd; unsigned long cmd_mask; struct nd_cmd_pkg pkg; int rc, i, cmd_rc; + void *buf = NULL; u64 buf_len = 0; - void *buf; if (nvdimm) { desc = nd_cmd_dimm_desc(cmd); @@ -1004,6 +1003,9 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, } /* process an input envelope */ + in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL); + if (!in_env) + return -ENOMEM; for (i = 0; i < desc->in_num; i++) { u32 in_size, copy; @@ -1011,14 +1013,17 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, if (in_size == UINT_MAX) { dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n", __func__, dimm_name, cmd_name, i); - return -ENXIO; + rc = -ENXIO; + goto out; } - if (in_len < sizeof(in_env)) - copy = min_t(u32, sizeof(in_env) - in_len, in_size); + if (in_len < ND_CMD_MAX_ENVELOPE) + copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size); else copy = 0; - if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) - return -EFAULT; + if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) { + rc = -EFAULT; + goto out; + } in_len += in_size; } @@ -1030,6 +1035,12 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, } /* process an output envelope */ + out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL); + if (!out_env) { + rc = -ENOMEM; + goto out; + } + for (i = 0; i < desc->out_num; i++) { u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i, (u32 *) in_env, (u32 *) out_env, 0); @@ -1038,15 +1049,18 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, if (out_size == UINT_MAX) { dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n", dimm_name, cmd_name, i); - return -EFAULT; + rc = -EFAULT; + goto out; } - if (out_len < sizeof(out_env)) - copy = min_t(u32, sizeof(out_env) - out_len, out_size); + if (out_len < ND_CMD_MAX_ENVELOPE) + copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size); else copy = 0; if (copy && copy_from_user(&out_env[out_len], - p + in_len + out_len, copy)) - return -EFAULT; + p + in_len + out_len, copy)) { + rc = -EFAULT; + goto out; + } out_len += out_size; } @@ -1054,12 +1068,15 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, if (buf_len > ND_IOCTL_MAX_BUFLEN) { dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name, cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN); - return -EINVAL; + rc = -EINVAL; + goto out; } buf = vmalloc(buf_len); - if (!buf) - return -ENOMEM; + if (!buf) { + rc = -ENOMEM; + goto out; + } if (copy_from_user(buf, p, buf_len)) { rc = -EFAULT; @@ -1081,17 +1098,15 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address, clear_err->cleared); } - nvdimm_bus_unlock(&nvdimm_bus->dev); if (copy_to_user(p, buf, buf_len)) rc = -EFAULT; - vfree(buf); - return rc; - - out_unlock: +out_unlock: nvdimm_bus_unlock(&nvdimm_bus->dev); - out: +out: + kfree(in_env); + kfree(out_env); vfree(buf); return rc; } -- 2.20.1