From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D1267432BDE for ; Mon, 20 Jul 2026 14:59:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784559577; cv=none; b=QwQP2JwQYvjGqPPbFLT+ZCSWI/t3Nr9wz9LThMtmilhKiUDr4A+bDPNCeMjMn4D7qHGqg45vONIBleejtUy9U1dfx/qdulrMATyI5pnpZ0WLvhXUXzQIOk1ScRIo0kVQaKm/oage1WczSJSlrBgJRwZ62YJrKY1VGHQz0grlTV0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784559577; c=relaxed/simple; bh=Ce45Ho8bF+USqECkTvaU5oiAi+bOBFbv6gw2NmmhgZ0=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=WUrrnni10uLcsWb0Kc9Ex0TYEqOI1i8SesuSWS276Wlp6c39BFuYtMp8+57ZqFkDcTlQLKf02ALG3XIvB+47pvoB6NmIVGk4J272cBtoNrmyctlkizyE9GlRY1gDr5LFwTIhCKCLkgpS2ijJKdVBt64dcwXtqZR3gbQh0n1wi0o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uTX8g9jb; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="uTX8g9jb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 440551F000E9; Mon, 20 Jul 2026 14:59:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784559575; bh=4hIZGa4gzehIdKvYauRC27xqCG/F3FvvTyKzz0qbeSc=; h=Subject:To:Cc:From:Date; b=uTX8g9jbTtogS9axO0y6QrGaWPesxLkivZcOva3RYvdyQ0S9+QI9VJEYIzWJnlAqd F4LSEMoXPicj3pJJhBy0B8OQAJ0mUpyVFh6b3IGR0GT3E0VrgYgTsL4bY/DaVzOOpk riFO+r18iRLeggwrsPYC5vMY19377EpHZoGNRGy8= Subject: FAILED: patch "[PATCH] net: thunderbolt: Fix frags[] overflow by bounding" failed to apply to 6.1-stable tree To: maoyixie.tju@gmail.com,kuba@kernel.org,mika.westerberg@linux.intel.com Cc: From: Date: Mon, 20 Jul 2026 16:59:26 +0200 Message-ID: <2026072026-jab-puzzling-567e@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 55d9895f89970501fe126d1026b586b04a224c27 # git commit -s git send-email --to '' --in-reply-to '2026072026-jab-puzzling-567e@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 55d9895f89970501fe126d1026b586b04a224c27 Mon Sep 17 00:00:00 2001 From: Maoyi Xie Date: Wed, 17 Jun 2026 01:38:41 +0800 Subject: [PATCH] net: thunderbolt: Fix frags[] overflow by bounding frame_count tbnet_poll() assembles a multi-frame ThunderboltIP packet into one skb. The first frame goes into the skb linear area and every further frame is added as a page fragment. skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, hdr_size, frame_size, TBNET_RX_PAGE_SIZE - hdr_size); A packet of frame_count frames therefore ends up with frame_count - 1 fragments. tbnet_check_frame() only bounds the peer supplied frame_count to TBNET_RING_SIZE / 4 (64), which is far above MAX_SKB_FRAGS (17 by default). A peer that sends a packet of 19 or more small frames pushes nr_frags past MAX_SKB_FRAGS, so skb_add_rx_frag() writes past skb_shinfo()->frags[] and corrupts memory after the shared info. Tighten the start of packet bound to MAX_SKB_FRAGS + 1 so a packet can never produce more fragments than frags[] can hold. This matches the recent skb frags overflow fixes in other receive paths, for example f0813bcd2d9d ("net: wwan: t7xx: fix potential skb->frags overflow in RX path") and 600dc40554dc ("net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()"). Fixes: e69b6c02b4c3 ("net: Add support for networking over Thunderbolt cable") Cc: stable@vger.kernel.org Signed-off-by: Maoyi Xie Acked-by: Mika Westerberg Link: https://patch.msgid.link/178163152194.2486768.14724194232649760778@maoyixie.com Signed-off-by: Jakub Kicinski diff --git a/drivers/net/thunderbolt/main.c b/drivers/net/thunderbolt/main.c index 7aae5d915a1e..ac016890646c 100644 --- a/drivers/net/thunderbolt/main.c +++ b/drivers/net/thunderbolt/main.c @@ -787,8 +787,12 @@ static bool tbnet_check_frame(struct tbnet *net, const struct tbnet_frame *tf, return true; } - /* Start of packet, validate the frame header */ - if (frame_count == 0 || frame_count > TBNET_RING_SIZE / 4) { + /* Start of packet, validate the frame header. tbnet_poll() puts the + * first frame in the skb linear area and every further frame in a page + * fragment, so a packet may not span more than MAX_SKB_FRAGS + 1 frames + * without overflowing skb_shinfo()->frags[]. + */ + if (frame_count == 0 || frame_count > MAX_SKB_FRAGS + 1) { net->stats.rx_length_errors++; return false; }