From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f49.google.com (mail-dl1-f49.google.com [74.125.82.49]) (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 EE9ED377034 for ; Thu, 21 May 2026 16:33:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.49 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779381211; cv=none; b=ELE55lNfeu1ojQnMPgOF8WMqjzzWOiybkZ0NvcVhRay8TlncwnKppKSKA6cfP5WgvMUA1dlxZOQw115AsvbxxH0Zwana7PSkomyQ3kAqQK0HHuS5GwnBmsbCFmcrHlAeJ42aqZY+1WE+7IfOuTmNuruC3LKLeo4O9qUjM+6fTCw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779381211; c=relaxed/simple; bh=9M3xO3sTTq8LHfcKIc5hA0ERvkIIJW2Gka+8g8Vit+Q=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=sj26LfwgFmhIr+ssHtjb1E+Ubn/hlgesP9lsfX7cyknFddxLyLFlwcnbSOA/qn4NjLdQFttO5aOy/8Kx4tZL+0hu663i+ZPgK5sTkuQOwv8Qaa6ou0FYa1medkPGV6ea/sAFvdFFtCZ4Y7zOfAZRQ/PJg0WoouTIDgayFhvg//U= 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=QcW034gf; arc=none smtp.client-ip=74.125.82.49 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="QcW034gf" Received: by mail-dl1-f49.google.com with SMTP id a92af1059eb24-1334825de43so5780856c88.0 for ; Thu, 21 May 2026 09:33:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1779381209; x=1779986009; 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; bh=z53ipK5w5yDvUUyH2xnve7gzJfjRxn1dpppTCEhJQdQ=; b=QcW034gfAMhINbdpmO1xvKKNvuRNrouot4zd8bvVxs/ZxjorM49m/UkXfNp0lvEapK 5PkXPwcrQwwHW/sNLF7XCTkOTC95jUZClmcbz4Xwi4LPVaF7h4OhIk1NCHcsP1cL0mYV ypgf+juni8u50XorI7TGKzIshQo7ZJD7xQ7o/eh0D/lPcZw7ZjD2ey55m8UAV65VgBpH 6JZgiyFpEE2s1VQxhgio7q5tl4VCyM1aTnK19DPykgmhiUZpyy94VYtoCKWrgOWoyDUp k0jr3f4fGcpgX9XAERz0fk3G9KZXA9Q7mHmlPoBsk8Gp/dp6PljfI8ZlmktCCxtsR1bD IXag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779381209; x=1779986009; 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; bh=z53ipK5w5yDvUUyH2xnve7gzJfjRxn1dpppTCEhJQdQ=; b=CpGv4xW4RLpFaVaew2DZdyReKDMiiulgpCsUeHxBbXPgt16h6yrNLZNbEsBa7YnrgM oAcGMe4eKoGXv1s7hKUOx9bTe06+s3nx9X7urQRUbw5qSR6ZxqZwV7Q4M3hm6koJe4ow 1qJQWcTHMW3km3idDGHVWKW5WzTX3UdQzY2i8Fv17yTshfsBnPYba3a5XOnYtDij6Gej D9u+EPSY4HjPyJacjM6kO/GDQF5fblNbU6XOX27KdsZiNYTvPLoBv6ngodX2Z6Xncv0t nlkFRnYRxK6A3DmYfwzDNGNsQVk+0vlg5ylTsohm0MOIjm1dDZd94y7DhkUqavpc/7Ai zTfQ== X-Gm-Message-State: AOJu0Yxl43NwGSA6ViqIFvtOn9f8NoJYNW0Z0xjcmCp/GtKp4hpK+wmq Kn44KxfyVw+TOMfRjshIZ49YgXHfN30wmJB9vuPlI+jv9763WX2WWEnerOSvUqR8avw= X-Gm-Gg: Acq92OHIeefN4k3q8hzE1PV+y9Prjm6dFDPDtIR20DRHRcnsC7jlGErrRqNR3SDu5sy Z7FQV7HWPtHgwf53i3Yg1VgiATNhwmYq5Vq8M3G8W71SOohphrfLXwO50tLrOX3v9ySUo3FGTvR jrNe4ruM3f0tjsqYcZTSs2D36iZKGL48EXol3KDtt5MepBbmB/H0Lq2SYUBuyDRPWhc6PW1xIFL AYPQgJjGvB8CauyTdmF0dI7QYDoxgANgnmZYD2ceNeOolSoKJmtzNcb1cgD3XK1B2SYHtZGoUQm 4gIipkDWS7Z/3IXxa0p3rWW0UvukBpSFVjFnYHgE88wG9494eJAR+PHFdk2znEwfU+919JOejXG V4O0FVH+4FUA1ZrqGw3iRt3e1oZFElE6+Pi7/17IoeoV18dRzNjeyM7C2M5K3RAG6HyqqSt23vp FZgaRCAh7EQlneCK30COQx8R4wTLCyW3f/DbCERrMFLxGi4bXGQBuhQ9MhajY32b/NDBSS X-Received: by 2002:a05:7022:1282:b0:136:4514:d913 with SMTP id a92af1059eb24-1364514d988mr1044457c88.26.1779381208956; Thu, 21 May 2026 09:33:28 -0700 (PDT) Received: from fx.tailc0aff1.ts.net ([206.206.192.132]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-13652ac2f39sm502917c88.15.2026.05.21.09.33.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 May 2026 09:33:28 -0700 (PDT) From: Weiming Shi To: netdev@vger.kernel.org Cc: willemdebruijn.kernel@gmail.com, jasowang@redhat.com, pabeni@redhat.com, kuba@kernel.org, edumazet@google.com, dongli.zhang@oracle.com, xmei5@asu.edu, linux-kernel@vger.kernel.org, Weiming Shi Subject: [PATCH net] tun: free page on build_skb failure in tun_xdp_one() Date: Thu, 21 May 2026 09:33:13 -0700 Message-ID: <20260521163312.1479805-2-bestswngs@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 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 Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Weiming Shi --- drivers/net/tun.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index b183189f1853..39e9f3390c91 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; } -- 2.43.0