From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Fri, 17 Apr 2026 11:12:48 +0200 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wDfFo-00D8Q9-2m for lore@lore.pengutronix.de; Fri, 17 Apr 2026 11:12:48 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1wDfFo-0004Oc-94 for lore@pengutronix.de; Fri, 17 Apr 2026 11:12:48 +0200 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: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=AtFsuIKWNgdAUe6F+eMS8uGnz6UYAtOmVjkGgHylbvs=; b=Pb1QfgaoDTGiyoXrtLWAzIaDYI EO1BXnxAcs7etuzjuNRzd6cSXTzSrK12WB48nui6L77lXQO/Rjc678IjvLmzS5BRctzwd0KUmg5GP /xsTWx/Mu1v1et489GWyhlb/TjnxmnGL0N2y0DvOu5hfrCJSUHhK/0YznXO7PyIUk5yTYRxMgkTgt oxtWd21SH15VRB+pvl61vVZk+Y6RbyS8zULuPEVvxEiS0ciRNNFxUpNAzMzpCv5fsYY9Sp9ynf9gI N2WQXaFx6eHQ9/sEAP6uuPOoKYfNtDjYBOUQDoquaDe9S+Q1CL5BYP04d9V0DLs0+iKFgctLCW0W2 Wvjd7xzw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wDfFS-00000003joT-3Rg7; Fri, 17 Apr 2026 09:12:26 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wDfFQ-00000003jo0-2Fgh for barebox@lists.infradead.org; Fri, 17 Apr 2026 09:12:25 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1wDfFP-0004Fc-29; Fri, 17 Apr 2026 11:12:23 +0200 Message-ID: <7adbb673-d7be-4671-ac01-9b996e1ed533@pengutronix.de> Date: Fri, 17 Apr 2026 11:12:22 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Sascha Hauer , BAREBOX Cc: "Claude Opus 4.6 (1M context)" References: <20260402-net-nfs-buffer-overflows-v1-0-5dc46ef1da81@pengutronix.de> <20260402-net-nfs-buffer-overflows-v1-2-5dc46ef1da81@pengutronix.de> From: Ahmad Fatoum Content-Language: en-US, de-DE, de-BE In-Reply-To: <20260402-net-nfs-buffer-overflows-v1-2-5dc46ef1da81@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260417_021224_601710_E1F9ADEC X-CRM114-Status: GOOD ( 17.34 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.2 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 2/2] fs: nfs: fix NULL dereference in nfs_read_req on truncated packets X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) On 4/2/26 9:55 AM, Sascha Hauer wrote: > nfs_read_req() reads the data length (rlen) from the server's READ3res > response and uses it to extract the payload via nfs_packet_read(). If a > malicious server sends an rlen larger than the remaining packet data, > nfs_packet_read() returns NULL. The subsequent kfifo_put() with a NULL > source pointer causes a NULL pointer dereference. > > Add a NULL check after nfs_packet_read() to catch truncated responses. > > Signed-off-by: Sascha Hauer > Co-Authored-By: Claude Opus 4.6 (1M context) Reviewed-by: Ahmad Fatoum > --- > fs/nfs.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/fs/nfs.c b/fs/nfs.c > index edc15e0ce6..d42ef6bc86 100644 > --- a/fs/nfs.c > +++ b/fs/nfs.c > @@ -1194,6 +1194,10 @@ static int nfs_read_req(struct file_priv *priv, uint64_t offset, > } > > p = nfs_packet_read(nfs_packet, rlen); > + if (!p) { > + ret = -EINVAL; > + goto err_free_packet; > + } > > kfifo_put(priv->fifo, (char *)p, rlen); > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |