From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dy2-f19.google.com (mail-dy2-f19.google.com [74.125.229.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 031694825C7 for ; Wed, 23 Sep 2026 14:12:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.229.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790172732; cv=none; b=n+pdnMi+WphPGCFilMbXfgvz1WWyScCdRPAm+KxLCVn6DMJLGo+4qPpJ5Xg6NKGTJEAXNzG+ZNbG9+myW46VMztyebGUijNSj38MorzV+WcAxKZvsoz2dXCVPcH3lGEciMxajWWQ3lKdgunl9hftD83FXoSlCyGj1uSs8Rq/d+c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790172732; c=relaxed/simple; bh=ktR9e2h8nCd9S0EFkl5DruJEUJcripKPI1tSmR1JOBs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=fOdQZH4O6E1nzrpsz9+WaIk8Yt/B5mfCf68Td77btoHIWEj26R2JyFObSHXxgZoLDMXTHM57hLj7m4y+NQEWrdOk3uBJU0cz2zVTIXuH8f+jeQWFpPlq5Ed9nJLrjo17B8/v+hvYwnw85SsvaJrFIBnGg+efkOjGvyyrNNS5WkA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=pRp7RS61; arc=none smtp.client-ip=74.125.229.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="pRp7RS61" Received: by mail-dy2-f19.google.com with SMTP id 5a478bee46e88-3286624d194so693204eec.3 for ; Wed, 23 Sep 2026 07:12:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790172729; x=1790777529; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=+ZvYoYp7T3tg2JMG9Cckdchh+Egbf2tNmPcdBTT/ZU4=; b=pRp7RS61spOd3YquanMz3ILiDZe8eHlW4x1rnIWd94D+4fOganFvcOPUe8A2kdakHK 4TBq6wSV11Otke9AyXZmkBBYvTEY6URiQVjYkEXZQpI2TBQyg7+VSXLkntRQ5pp0b6Te fXpxsue7zMjEdWg678URa+ONc3SIeFx2s0PsP7mlWZKI4iQyVisjAAftV7SxpHjkkaeI 31iclWvQ04FX32JZ3a8a1LxcKxJC7H/uz5CEZxATZfKYw6k5s08bm4sZ+z9JRSFl+QzA ImD0yuJmFtW6SRfX7gUhCwc3xq/HZkYTv2lM1xIqYKc3XFcgEueLb+7b9uNNL9DDfyH5 K0AQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790172729; x=1790777529; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=+ZvYoYp7T3tg2JMG9Cckdchh+Egbf2tNmPcdBTT/ZU4=; b=E1TaT+KS0lkcvBVXmBIwi9LWMtfyYrQ2OxITFhNMRStDUQNQ5NGYWO2IngOlZnvCC1 gHDOSj4qQOFesZYZJ72AI2UyU37eJ1MqhXtzirmKKEi17zvMDPvfYLwdSmmp6bdMsaKa 0egDIzvtd/u4I/XghTyQnMqvtrZTkIOA0I7rpqIZecoXP0cEC3HpHB0bki55JE3EI5Jv TbwKtD3WV/Xl9ABmtcv/7CcCukFChUd4R0BcFhbb1H9VPbVwtTYH7v01BQ1XLmfAGxaF +1cLErbA1s5rm1Bz38aKVRJ9JJmu44GnnYnIsBIsdajIG42WU6kUujpD8Kired3yzeam di6Q== X-Forwarded-Encrypted: i=1; AKwUvBwldtkl3c/eT3/O6jKd4uO9/9FcpVknTEpoq2ozcYI0lMdcKnxQlHXeKMHhBn7eN1Gl8E92sJ0=@vger.kernel.org X-Gm-Message-State: AFuF++kZAw0BLxsf+n+krh2hACfGD7aU6yIhloXsnRtkowrO8YKnQjnD 93L0DeGr55pGwDR7LKY73jJkM3w7s9otXwLg6XReejgrzlOfvUV8xSzk X-Gm-Gg: AYBFou0A7lsbzUF8az1DZHM2EIOfWxM1PKMD7RSyVs3NgTATAeZPGNxjXUlhRYXfIZQ YHxYbGcFg3Sh9Osm0Sej35ANj1UL7gteDjjQAARzZmDlYlk0VV7UERObpxkuu8nHmXh+4My9i4t Lee8ZqremIA4DpbSxZ90GtAbETjdBEhP5x/+ju6HA62w1VOCU1cyb18amR3xmOMMPsGByTo7M1x 9UgjCRqlncFFuJFpXR9idUA3vSG657oEufK1y2nu0u/tzEYK55gm0ivDgqbxYQL77CAVwjOHhPo ijT03KKTX7BOKc4rT5UtSZsDUg3GAgwYEEHYD3OdCW2uXWeHLkjhC4a6eIZf29lujd2HbZKWqtW 5GFwDaZB1CSSQ1U7rApkOW2qKNFukQCR69lZ3+DYGp7Xrf+7MqxLZD5MEm4rCSdZWATUmdx34Ap eLH8AVlf54WAxLbMXxzm0dl+k/1RKeU4Mth12AO0FTJJkktbRH9LMODNOy9w+GDMCW4n+rDMZuA A== X-Received: by 2002:a05:7301:6196:10b0:33b:fc9d:947f with SMTP id 5a478bee46e88-33e8ea87051mr2781245eec.40.1790172728561; Wed, 23 Sep 2026 07:12:08 -0700 (PDT) Received: from beelink.. ([187.13.30.172]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-33e95c7cfd9sm7193489eec.5.2026.09.23.07.12.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Sep 2026 07:12:08 -0700 (PDT) From: Aldo Ariel Panzardo To: wei.fang@nxp.com Cc: frank.li@nxp.com, shenwei.wang@nxp.com, imx@lists.linux.dev, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Aldo Ariel Panzardo , Sashiko Subject: [PATCH] net: fec: reject oversized fragments before bounce-buffer memcpy Date: Wed, 23 Sep 2026 11:11:54 -0300 Message-ID: <20260923141154.2415545-1-qwe.aldo@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit fec_enet_txq_submit_frag_skb() and fec_enet_txq_submit_skb() copy transmit data into a per-ring bounce buffer when the source address is misaligned or the FEC_QUIRK_SWAP_FRAME quirk is active. The bounce buffers are allocated as kmalloc(FEC_ENET_TX_FRSIZE) where FEC_ENET_TX_FRSIZE is 2048 bytes. However, skb_frag_size() can return up to PAGE_SIZE (4096 on most architectures) for scatter-gather fragments, and skb_headlen() can exceed 2048 for certain GSO packets. When this happens the memcpy overflows the bounce buffer by up to 2048 bytes, corrupting adjacent heap objects. Add a length check before each bounce-buffer copy. If the data exceeds the bounce buffer capacity, fall through to the error path rather than performing the out-of-bounds write. Fixes: 6605b730c061 ("FEC: Add alignment handling for FEC driver") Cc: stable@vger.kernel.org Reported-by: Sashiko Signed-off-by: Aldo Ariel Panzardo --- drivers/net/ethernet/freescale/fec_main.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 794ec42..8614984 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -558,6 +558,8 @@ fec_enet_txq_submit_frag_skb(struct fec_enet_priv_tx_q *txq, index = fec_enet_get_bd_index(bdp, &txq->bd); if (((unsigned long) bufaddr) & fep->tx_align || fep->quirks & FEC_QUIRK_SWAP_FRAME) { + if (frag_len > FEC_ENET_TX_FRSIZE) + goto dma_mapping_error; memcpy(txq->tx_bounce[index], bufaddr, frag_len); bufaddr = txq->tx_bounce[index]; @@ -634,6 +636,8 @@ static int fec_enet_txq_submit_skb(struct fec_enet_priv_tx_q *txq, index = fec_enet_get_bd_index(bdp, &txq->bd); if (((unsigned long) bufaddr) & fep->tx_align || fep->quirks & FEC_QUIRK_SWAP_FRAME) { + if (buflen > FEC_ENET_TX_FRSIZE) + goto release; memcpy(txq->tx_bounce[index], skb->data, buflen); bufaddr = txq->tx_bounce[index]; -- 2.43.0