From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f70.google.com (mail-pj1-f70.google.com [209.85.216.70]) (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 CA041367F59 for ; Sun, 23 Aug 2026 18:36:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787510164; cv=none; b=c8X/eMoeubVnlX3T0XvUuWc5Waz2ZBRNpRb/hFY10mqXs/5YKo7O8DIulSSjpOHg/FfVy63uv46yiRM42MqhwurO7GBqxpjuIGFs5XF/momYi9vtIADbZM3XT8siUVYJgThQcxdWB3F0bx1ihKePje09HCoGvL/u10KtUtu/MKM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787510164; c=relaxed/simple; bh=BhPznQ+Ob1glckQETuNATKlL3cpZxbSPU+Z5vfvw6vk=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=BNAjBjND8fJ77JO2PL2IIhUpr2hdbQ+pBO6tIjqv4YJmkjjDlQ1Z2hGkwYlHXLuaCe57a4/GRgiK3LlJIA4cOBmIaBgoZJEPwGzksbUtTUZ1ulKvGfi1YZLZMXY42EX4dxnAtVeWtt4hveCHwjSvTD9AJpTLuMUhNJ3Ynn0LCAg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=LBdhMhx/; arc=none smtp.client-ip=209.85.216.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="LBdhMhx/" Received: by mail-pj1-f70.google.com with SMTP id 98e67ed59e1d1-38ecc48b3c2so4512746a91.1 for ; Sun, 23 Aug 2026 11:36:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1787510163; x=1788114963; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:mime-version:date:from :to:cc:subject:date:message-id:reply-to:content-type; bh=Y77FEMam/I5QOXZIpVfbp3+3bLbGABxpssJ/EqST3pg=; b=LBdhMhx/RNAeZdnVTc/nKeO9LHDGzk4M65W0Mjaf8jrD2tz14qUM82UoncLbhcD9tC yoVhbY4M0V1wGXyghdWppbTPeMQER0I9gg7gr3FnB0FLAJEjKJBMonAAWBdArFVGfi43 zAEq0C7caakZF0p+4HbR11iKR+kMY9Cd+MYUwmJp6ew3HNwinM+FhQllrGVyuxyKrAsQ O0IjR6Mt+DuDzje11o/GwC1zs8d7bLTyw4kID1YRKQJw5WsLW/k2BcwesKi91Qkz3Ww0 e0Vy/wXVnj/PFVHslX3DWYk9m5jjCZ3efwFfWi4znZQNaOPNzFuHLo2AbZC0PgPQBIXq YyoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787510163; x=1788114963; h=content-type:cc:to:from:subject:message-id:mime-version:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=Y77FEMam/I5QOXZIpVfbp3+3bLbGABxpssJ/EqST3pg=; b=VV7P/kL07c1JQFUH+C+/pUB28dHtv0oe8nhrkfrIYLqJAz3f0urSx3hWjJ0p2znkpM jfF0O/dUmF3HkGa/G+0pyoremTLuv2+x/hGv9RnaRRMKCq+zF+5/x2qHwh+8P7GF+UUv HpreL+rMxS4I0USmGp1XZqENLGJqS7y/OQuPwWGedEIEIkAVGQoVPE6KILfwV99ebd09 cCHp6XCZx/NGiqF6IsTuFCbOnmLz+xq2Ur3zZc0keK2yhLC6JQVtN1/0o1EKjXQfPMwS TEFm0AjJ8eOfJzgmnvP8t2soQkZhg3vi+IXNrMRLLTzMJG3UY3XJlAZWulxOVk2EREv0 yizw== X-Forwarded-Encrypted: i=1; AHgh+Rq8l0Bb2+BhSDUFjijxLYcYyXxnYeOtO+mY1InAB26PrkIxJGvBsWfmO+C291VxPePu3Dn+CNUlW9WbRnY=@vger.kernel.org X-Gm-Message-State: AFuF++kZkom3htr/dntaVgyeUm1K/jS8niBRsoeTiZXddhNxw29ytWap NXV/RyhTG27x5m/uthfOHu6qp9oMfx5TqPvXOBjAH3HWGGgI2v761cLF3RH8k8DH2p5smEkCnqS OROUzEmYqLsOeaws3tZE9qYZuKA== X-Received: from dys24.prod.google.com ([2002:a05:693c:8018:b0:324:1657:4d0a]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:4b02:b0:36b:bec8:94c5 with SMTP id 98e67ed59e1d1-395df2595femr20809097a91.10.1787510162785; Sun, 23 Aug 2026 11:36:02 -0700 (PDT) Date: Sun, 23 Aug 2026 18:36:01 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.55.0.766.g2966f0265a-goog Message-ID: <20260823183602.1051453-1-almasrymina@google.com> Subject: [PATCH net v1 1/2] net: core: check skb_frags_readable before uncloning in skb_copy_ubufs From: Mina Almasry To: Jakub Kicinski , Kaiyuan Zhang , Willem de Bruijn , Mina Almasry , Eric Dumazet , Zoltan Kiss , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Paolo Abeni , Simon Horman , Jason Xing Content-Type: text/plain; charset="UTF-8" skb_copy_ubufs drops clones and modifies the SKB via pskb_expand_head() before checking for !skb_frags_readable(skb). This alters the SKB geometry prior to throwing an -EFAULT on an invalid SKB. Check readability first. Fixes: 65249feb6b3d ("net: add support for skbs with unreadable frags") Signed-off-by: Mina Almasry --- Note to sashiko: if you find pre-existing issues, mark them clearly as pre-existing. --- net/core/skbuff.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d4382b68d56e0..201c9ec1519c7 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2001,12 +2001,12 @@ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) int i, order, psize, new_frags; u32 d_off; - if (skb_shared(skb) || skb_unclone(skb, gfp_mask)) - return -EINVAL; - if (!skb_frags_readable(skb)) return -EFAULT; + if (skb_shared(skb) || skb_unclone(skb, gfp_mask)) + return -EINVAL; + if (!num_frags) goto release; base-commit: 7cbfb180945ce529608e4d4e24a6d483699fab1e -- 2.55.0.766.g2966f0265a-goog