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 4E5B678C9C; Sun, 7 Jun 2026 10:06:10 +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=1780826771; cv=none; b=Kc23Unz8SrLEcJCOQZP1T0t+CoXJKz1SbK7OrmYweVnVV2juAHfpJCKgMc3dtpNeC+kFP6vRtIKbh/K+6kHXNxperM8mklzkrEWXKzNZL3g3Y1p9x7cek9CT777EcBEYuetgjO/EAGvCCWG5rj8M8f5H92H2RkVBn0uw3c2i4Zw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780826771; c=relaxed/simple; bh=GodA7kWoUWgofy4+4FB/bNj6Tcor11TQf61VSD5uPLg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lElMKmDaI3y5XZRO5ZyLyPubNAutt+i+TWHqiOI2hhefSxXBXp0w/l42/B/a/g8G2RSO2hRlKzvknHVhL+Dug9FQrH2FjnPwmTlAqfrMkBIO9vOSaSrGr0l98tD0p67B333K41LUyhkL9WT8ykd4g2++guvvbAQk7QRVStEpPXM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UJIpTwih; 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="UJIpTwih" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4933D1F00893; Sun, 7 Jun 2026 10:06:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780826769; bh=sdgItA8OJLCvvwF7fj8lhPuoAmZIsCsZJ8VUQ/3j3Kw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=UJIpTwihsZmQxWHijdjuBU8041Jk7WA0WVt67uLUCv2GsJGjK4pe533eMqPgF38i4 t9c08tZMj4ajKML0fFuKXaYAs3Cd+8IufXwsotaqCps+hGK3lGTfmzqw5TTgv0aV4N DcY0b/oPnkKJdhwEw1h0Jyv2HNOXllH/sJfueaIQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xiang Mei , Weiming Shi , Dongli Zhang , Willem de Bruijn , Jakub Kicinski , Sasha Levin Subject: [PATCH 7.0 023/332] tun: free page on build_skb failure in tun_xdp_one() Date: Sun, 7 Jun 2026 11:56:32 +0200 Message-ID: <20260607095728.922672474@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095728.031258202@linuxfoundation.org> References: <20260607095728.031258202@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Weiming Shi [ Upstream commit aa8963fdce667a42fb7f0bdd2909fadcab02f9a8 ] When build_skb() fails in tun_xdp_one(), the function sets ret to -ENOMEM and jumps to the out label, which returns without freeing the page that vhost_net_build_xdp() allocated for the frame. As with the short-frame rejection path, tun_sendmsg() discards the per-buffer error and still returns total_len, so vhost_tx_batch() takes the success path and never frees the page. Each build_skb() failure in a batch leaks one page-frag chunk. Free the page before taking the error path, matching the put_page() the other error exits of tun_xdp_one() already perform. Fixes: 043d222f93ab ("tuntap: accept an array of XDP buffs through sendmsg()") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Reviewed-by: Dongli Zhang Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260521163312.1479805-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/tun.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 8154d18a2a235a..ca0ae5df73af78 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -2437,6 +2437,7 @@ static int tun_xdp_one(struct tun_struct *tun, build: skb = build_skb(xdp->data_hard_start, buflen); if (!skb) { + put_page(virt_to_head_page(xdp->data)); ret = -ENOMEM; goto out; } -- 2.53.0