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 F3E66C77B78 for ; Thu, 4 May 2023 19:52:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231772AbjEDTwX (ORCPT ); Thu, 4 May 2023 15:52:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231382AbjEDTue (ORCPT ); Thu, 4 May 2023 15:50:34 -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 C5138150DF; Thu, 4 May 2023 12:46:54 -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 29DF26375D; Thu, 4 May 2023 19:46:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AFD50C433D2; Thu, 4 May 2023 19:46:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1683229605; bh=f84D5WyFdSwh29Ao5yQKxvAWap/3U4GPVj/72rrimQ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RLgqIUtezNt/nnKpC1vqyNv8+pyGm0bHwgzhzCBiMDBIvr3ptLcLBjuQkHFH6QMMN hiIv3bkgFNUQ4jpuJEk4cTbia3Ro765ymc+sw7toCxRpjw9IL0LdkytYtoX7g18kYy INwxgRd/h3jEREYpVdNUKrHnVlh+iQdQr1p5+SQxV7ho92Yw9fAzfRqP/uyxtGPy6g RWshAUsyC4GRBPI3yvWZxPIthWNPJSrJDzYHyXgYIrNsQTI8805zkF3ciRGVlh/gGw WpgvkrN1CjMBafFqNBPX4F8ypVWKXiahr+SYAhEeoyIiskteUKuRhXvqkq8QpegJG+ ZhOTfNgdlNRXQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Justin Tee , "Martin K . Petersen" , Sasha Levin , james.smart@broadcom.com, dick.kennedy@broadcom.com, jejb@linux.ibm.com, linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 6.1 07/49] scsi: lpfc: Prevent lpfc_debugfs_lockstat_write() buffer overflow Date: Thu, 4 May 2023 15:45:44 -0400 Message-Id: <20230504194626.3807438-7-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230504194626.3807438-1-sashal@kernel.org> References: <20230504194626.3807438-1-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: Justin Tee [ Upstream commit c6087b82a9146826564a55c5ca0164cac40348f5 ] A static code analysis tool flagged the possibility of buffer overflow when using copy_from_user() for a debugfs entry. Currently, it is possible that copy_from_user() copies more bytes than what would fit in the mybuf char array. Add a min() restriction check between sizeof(mybuf) - 1 and nbytes passed from the userspace buffer to protect against buffer overflow. Link: https://lore.kernel.org/r/20230301231626.9621-2-justintee8345@gmail.com Signed-off-by: Justin Tee Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/lpfc/lpfc_debugfs.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c index f5252e45a48a2..3e365e5e194a2 100644 --- a/drivers/scsi/lpfc/lpfc_debugfs.c +++ b/drivers/scsi/lpfc/lpfc_debugfs.c @@ -2157,10 +2157,13 @@ lpfc_debugfs_lockstat_write(struct file *file, const char __user *buf, char mybuf[64]; char *pbuf; int i; + size_t bsize; memset(mybuf, 0, sizeof(mybuf)); - if (copy_from_user(mybuf, buf, nbytes)) + bsize = min(nbytes, (sizeof(mybuf) - 1)); + + if (copy_from_user(mybuf, buf, bsize)) return -EFAULT; pbuf = &mybuf[0]; @@ -2181,7 +2184,7 @@ lpfc_debugfs_lockstat_write(struct file *file, const char __user *buf, qp->lock_conflict.wq_access = 0; } } - return nbytes; + return bsize; } #endif -- 2.39.2