From nobody Sat Oct 4 17:31:18 2025 Received: from mail-pj1-f52.google.com (mail-pj1-f52.google.com [209.85.216.52]) (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 484B029A2; Thu, 14 Aug 2025 01:01:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.52 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755133282; cv=none; b=oq8bYfGddNIiNgXOm/aiK+fbS8ysWqg8e+NOLH22iJCNlsXQI1Wsgj4E3Rr8jWuxQ+nhJUKK8guC21H6nZpTUS7nJAixkmPhUR/JpATVOluXt4+zvuvSbYIJjJCjVJColj+TU6Y8J8kvy7XkIIuf6TTmZ0NGrBuCCb3RjMHaLFg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755133282; c=relaxed/simple; bh=BgYADDZNn1QGP8McyCKnNLHgPx6xFyxwoBH73J/vNdY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Lsu2LnQaOYmGslFBVvfPOGwOMIXexyFb5pAefmn4KTSYW2Mo7kpL52ty0uC8CM/O1ZEc7crIq/VgKj3zB4AOVRvlf+CG6sTysnrZ3Gt2KKuCsQJ2aciADDndPlTy1bwjzyUU0hGR/0WMyvu4iN68vePTyqzpjPNRYckML2p/W/M= 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=VJrdgbic; arc=none smtp.client-ip=209.85.216.52 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="VJrdgbic" Received: by mail-pj1-f52.google.com with SMTP id 98e67ed59e1d1-32326e8005bso496691a91.3; Wed, 13 Aug 2025 18:01:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1755133280; x=1755738080; 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=kmRK/OcA855B8uL5oM9h+iArfFvDj2KGuj3BbBAIWG8=; b=VJrdgbicpBJeD7Y0otxXNDcDVoJ6Emn/IiuUYH99jMZicRuFlcyE0GPYQh5g+i8XpT KgrI6stzDyAKL8wti14R8uJig7I5OohPzWnEGcfoGB5wnsf7yiCYP98XKbaCYIoNtg6u VF8OyFa9gLAZHH3NiAOBT9QlRWmTD8D3zbFiZaMRuEt8KV0QzZ0M8y5RGCeVvj2EJcQs XvhiRrc5Az1hrTI5ZImVFtRr55vh6yflxt0tm9i0/+gFWlkQyz9evMAXsKNRfNX5yTAN jhP6+YuyuQjNjzEKX8dJUU8dYuCYLvUkKQGJLSutwUKdonRW1ykjmw87OPNKs+Y0j32/ n4lA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755133280; x=1755738080; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=kmRK/OcA855B8uL5oM9h+iArfFvDj2KGuj3BbBAIWG8=; b=qDljnSUdu8Yo1mfAtWq5zz6zGKX4WmAiawx3c6zBrFVummJWMFkk9EPVdJHRJGpQ6x 9/wTc6P2n6JREJK79IZZGEcwBHex6Px57ITpTEdNZiR82jPLGISHwHuWZz0yoLHRGZgd qA16NpXqIbxIevfsWzkTuD8F5ybzKr+TRaDghitOdoDmeR+8qFSjt4967LYYU60AMIhP APmKVAba+ObZhx9eXfzK/EJJUZ/7ZOQ62q31EGsbzKIsB9xH0HxrdbmCoO3FmocvEz7N ZxT4l9dblwh0CNMm1qRrQvezoOQcl2/QOy5STye4z59fexTWtNleApz6GdrT3gbgdJ6s bquQ== X-Forwarded-Encrypted: i=1; AJvYcCVyV0SGO9oPoTfCix3XMsfUdl1l353CFPf9FKniR5FoxXqW+ogwS08cuzMcj0HjuJOszutx+ez93nMYxlc=@vger.kernel.org X-Gm-Message-State: AOJu0YwHTg5b1QWTyLcDmVLmzZOpY4jnYxCI3SFXIm4YwfO4XtEzCP7K YHmbrYxidQJpIRCpU9LXLEAXvArsI8cOrqN565BVxTeng2VRA442P6rw X-Gm-Gg: ASbGncv/Ec/15YPcGjOsAhJwX2heZCLYdrOyHpP/Untw8gatlAiYhuoc2eDVRQ/MOML o7irMtNCW/0uu0UIDWgOaNtQAAm0Sfv74exjMBCSYTN12/pWi1bGiEU6LegKJbp+jmFCTc93SEe aG5O/3SXviTEGZ+5RiLzlyHMbIUbF3AVX2F22t7cfs1KLyQX0ihghEgW0jW78BWKJDmhZZZq+uF 8Asr+QXfowtiywfT2Ffizp6fEExC3WuVvgr5y1Fr2hplI0HFwkZJsmlbWjrGexaCWrjieVuDkXJ Gpsxt1cNfcgsBWWSVsXtny0IZu2vSMyGDP0X3bZH6gqLVhsJ2m1UWMZwqX1GP8k/bdVrcoidAN6 x3OwmY8zMgvTtqMRYnNtmO5kQvmkJVWaIYTnTCkI= X-Google-Smtp-Source: AGHT+IHDR6XFwjRkc0kzqrP7D67S7zPiaBmX+TUC2HvECQZ+ZVfklosVZ/Uw+7Oh/OvHf5p5iL9bbQ== X-Received: by 2002:a17:90b:3c05:b0:31f:ad:aa1b with SMTP id 98e67ed59e1d1-3232799c039mr1746682a91.3.1755133280318; Wed, 13 Aug 2025 18:01:20 -0700 (PDT) Received: from C11-068.mioffice.cn ([43.224.245.178]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-b46ea0780d8sm6785378a12.29.2025.08.13.18.01.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Aug 2025 18:01:19 -0700 (PDT) From: Pengtao He To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Willem de Bruijn , Mina Almasry , Jason Xing , Michal Luczaj , Eric Biggers , Alexander Lobakin Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pengtao He Subject: [PATCH net-next v4] net/core: fix wrong return value in __splice_segment Date: Thu, 14 Aug 2025 09:01:11 +0800 Message-ID: <20250814010111.15167-1-hept.hept.hept@gmail.com> X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" If *len is equal to 0 at the beginning of __splice_segment it returns true directly. But when decreasing *len from a positive number to 0 in __splice_segment, it returns false. The caller needs to call __splice_segment again. Recheck *len if it changes, return true in time. Reduce unnecessary calls to __splice_segment. Signed-off-by: Pengtao He --- v4: Correct the commit message. v3: Reduce once condition evaluation. v2: Correct the commit message and target tree. v1: https://lore.kernel.org/netdev/20250723063119.24059-1-hept.hept.hept@gmail.= com/ --- net/core/skbuff.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index ee0274417948..23b776cd9879 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3112,7 +3112,9 @@ static bool __splice_segment(struct page *page, unsig= ned int poff, poff +=3D flen; plen -=3D flen; *len -=3D flen; - } while (*len && plen); + if (!*len) + return true; + } while (plen); =20 return false; } --=20 2.49.0