From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Thu, 02 Apr 2026 12:39:36 +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 1w8FSa-007odr-1q for lore@lore.pengutronix.de; Thu, 02 Apr 2026 12:39:36 +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 1w8FSa-0007rY-0W for lore@pengutronix.de; Thu, 02 Apr 2026 12:39:36 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XTXBU41CbHL/fbTaOxdPiVTABTMzGr0j8Kt5wjGvhq0=; b=qE4/GR2c0zZAXH4UtlyoIJjVKT +7YB4fGfMumU68Xf/8DZPzNK0GK2H3V/DXCgOGdVgPIV8o1nFpHEXWipwrCYJ0vwdLNAB8a1NO9if XNPBHWJI6IU5k0OWLMOLJrDnkVQLIPZ3bu5p1fcg1Y0Wl5R+brHMmdQDy+w16VptaeUuLKmerD3So 8llYnE+bU92Pry9ibFjv5Xp/RRV8OQh2rJwY7RhVkfgAexe8GmKNavNK8FgW3stjbCAqdvwuOGKUk bX1MVzhHuLAEMjb7m5R8KYwOZtfhjRBLk8yb74yTOk2OvQp8cnkCitjFCYiBTu/dpOVlDgh05Q52L A3PTM+tQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w8FS7-0000000HQ6n-2h9d; Thu, 02 Apr 2026 10:39:07 +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 1w8FS4-0000000HQ6C-06JD for barebox@lists.infradead.org; Thu, 02 Apr 2026 10:39:05 +0000 Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1w8FS1-0007kJ-Ti; Thu, 02 Apr 2026 12:39:01 +0200 Received: from pty.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::c5]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1w8FS1-003MKC-29; Thu, 02 Apr 2026 12:39:01 +0200 Received: from sha by pty.whiteo.stw.pengutronix.de with local (Exim 4.98.2) (envelope-from ) id 1w8FS1-00000003Arp-2M6m; Thu, 02 Apr 2026 12:39:01 +0200 Date: Thu, 2 Apr 2026 12:39:01 +0200 From: Sascha Hauer To: BAREBOX Cc: "Claude Opus 4.6 (1M context)" Message-ID: References: <20260402-net-nfs-buffer-overflows-v1-0-5dc46ef1da81@pengutronix.de> <20260402-net-nfs-buffer-overflows-v1-2-5dc46ef1da81@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260402-net-nfs-buffer-overflows-v1-2-5dc46ef1da81@pengutronix.de> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260402_033904_063865_983ABC24 X-CRM114-Status: GOOD ( 21.30 ) 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=-5.1 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 Thu, Apr 02, 2026 at 09:55:24AM +0200, 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) Fixes: 5be38817bc77 ("fs: nfs: do not read past packets") Sascha > --- > 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); > > > -- > 2.47.3 > > -- 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 |