From nobody Sun Feb 8 15:59:17 2026 Received: from mail-ot1-f71.google.com (mail-ot1-f71.google.com [209.85.210.71]) (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 85DEC3557EA for ; Wed, 14 Jan 2026 12:33:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.71 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768394024; cv=none; b=h4xgtL6Oy36PfD6IauNvc+bwhBhMCrAPvoabVY+RDB+OwieiDE0hIujp1KWTuPjBIJija6xGQMjf6c67OYD0latymsoi2GYHG5n1ujnK1xy9Kw5fwk7JJwkQPYtFh4Vp6dEdbc67rK8O6rLy+f0BL8nlp+XxFiZpj+iTlJuxYOA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768394024; c=relaxed/simple; bh=7m4giFI5N8akLpJq22sXLjscPH6ZNSd+YRyoIdvG2aQ=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=BB7RF8T+8SzsRvxYgzMQjKB+ysxYpy4v6bQ6ilEFgX81QPiWxgD84BUmcSYVRmGQuUfixqRA9LEWFs8feSCrtXlKRV3sHYm1v+Xc/T/ACen2pr04SHaZKWx4iDu48tv5sL17ET0zM/6NpiI4ZdBfQch4hh+fD7yM4nMbbw9uj+s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.210.71 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-ot1-f71.google.com with SMTP id 46e09a7af769-7cfd106018aso132462a34.3 for ; Wed, 14 Jan 2026 04:33:43 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768394022; x=1768998822; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=BJqpB6RjYF1KOPBYXbZO1FWziGKH8mOeEDiPzahopoY=; b=RKpxh1/GY5QBJllR+lntLKyBfD9YdChY2rn7tRemWDwqQMWdMIHaI2BvBJDZWxqPPS wAzpaYvckwzEk90fhNZIRCD6wvtVgocGVDR6g6ZTeywemiLjK5OUMGBJUIslvCCPJai4 a5RH2/0mSQb3WGjTsFAnQIP8cMto0uy/K9VABSM/epdpz1mNyU0ajV0HtQfTBrhPHYCc 1z3EO8ZLFABd9sNl/BV0SKJas/o9SEu+OCmfI+gPUmf9baroBCszDDeqPNRa9wg8Zx32 4/CX2JE+24ZuLCK4ZAIPC+7daDzugI/SUdwOCkzOaniWxlNuYzgbtP4Sua1z+lV97Wsj 336g== X-Gm-Message-State: AOJu0YwkzV4QQLFqz83zLmDjd4qtlfC7jUoI0Ks7ejWyaCPOXX2sM/XU Fb5rLDreWhpoFKezZhppQyerdOHs0ggFEuY0EdVaiYlQyWReWxlp3gRGsTVyZu/CDK51TOL0Eon wq6MsZ86knPdHEr2bqKJr+49sMhGROVz2Q+q7P8EduK1PBAhYy5mLhymw+go= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:16a3:b0:65f:6df9:2149 with SMTP id 006d021491bc7-66102c56daamr1298856eaf.33.1768394022515; Wed, 14 Jan 2026 04:33:42 -0800 (PST) Date: Wed, 14 Jan 2026 04:33:42 -0800 In-Reply-To: <6954bc70.050a0220.a1b6.0310.GAE@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69678d26.a70a0220.3ceeff.0000.GAE@google.com> Subject: Forwarded: [PATCH] net: skbuff: fix uninitialized memory use in pskb_expand_head() From: syzbot To: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org. *** Subject: [PATCH] net: skbuff: fix uninitialized memory use in pskb_expand_h= ead() Author: sohammetha01@gmail.com pskb_expand_head() allocates a new skb data buffer using kmalloc_reserve(), which does not initialize memory. skb helpers may later copy or move padding bytes from the buffer. Initialize the newly allocated skb buffer to avoid propagating uninitialized memory. Reported-by: syzbot+619b9ef527f510a57cfc@syzkaller.appspotmail.com Signed-off-by: Soham Metha --- #syz test net/core/skbuff.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index a56133902c0d..b0f0d3a0310b 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2282,6 +2282,9 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, = int ntail, data =3D kmalloc_reserve(&size, gfp_mask, NUMA_NO_NODE, NULL); if (!data) goto nodata; + + memset(data, 0, size); + size =3D SKB_WITH_OVERHEAD(size); =20 /* Copy only real data... and, alas, header. This should be --=20 2.34.1