From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f49.google.com (mail-wm1-f49.google.com [209.85.128.49]) (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 D86F03D8114 for ; Mon, 29 Jun 2026 07:28:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.49 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782718122; cv=none; b=YrwI3rFg1hPKyJ9JP83uDjRqH2RutwtT75Qgr02ckp0ZwgDh9nk9vV+O3yZFbbzwFAeEvZ3cJfrrDAx4b8iTrKrcZP+yY1lQZi1XsUw8ZrNnH3jepE9G1DvQevYOtgtNPDcTk4HmnShxzOpUABh9+3/2tivO7hb5oP+RCZtYS9Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782718122; c=relaxed/simple; bh=lQpHZi11cKsP2uCr/CzXPM2KCFMIncW7KSkiCY3Sf8o=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=qVP2DDHGc4oJUPy67DttrvpWxQmHQ/CE0iJdRdA4tL2S+O7oQI+HfBzzfYc2w+0WxBiJhSCfjK+1vuK0xOLK5PEJqHjIjKwBtvQb/D7/8R2b7aybqqyGakHzMkKmQdL+ZPyCagc84cTRYXnWXAtLMmXcElwBbw6bQ3SwW8Ensls= 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=UrOxzvN/; arc=none smtp.client-ip=209.85.128.49 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="UrOxzvN/" Received: by mail-wm1-f49.google.com with SMTP id 5b1f17b1804b1-493b27c7451so2659485e9.0 for ; Mon, 29 Jun 2026 00:28:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782718117; x=1783322917; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=lQpHZi11cKsP2uCr/CzXPM2KCFMIncW7KSkiCY3Sf8o=; b=UrOxzvN/VLZyexkM42OPh/9OB+oBzCCqGQnoAOCIPya+wOdsU0frbhCb2fR7dUu7T+ IlnRyU7B8j4zKGbfdKVaHuQxRGxpsx6/YtqSkvLFEsnai3kZuY1cWl9NDpckegzAqfQ4 Ao3bcEPd1zl29neZKxRM6iionnN0nE/ZYbQKSOEu5UhwFBFYacqYtiQ3hlVIBHkZ+eBR Q8EFYPW7bgSTvEo65YBJ2j6JBqQsa+IruDkro40c/fidgxZljjdRzB7MKKETNBcGo7ZY lLvXj0kTHJFjcbGUu/XXAEAJgKp4p8Wo3NUv5kBwSygAVWDbkl1ZJgOrAjNfKYzn2+YA XYGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782718117; x=1783322917; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=lQpHZi11cKsP2uCr/CzXPM2KCFMIncW7KSkiCY3Sf8o=; b=AIHhRf2rL3UWBoYSsnA79y3xASJROESw5yOnTMHgkxnRTJee4N9IqWU7BWusWM3vSM sh2DsaTr3YC1lXAjufmZXbNDC+DuVvmg/NNPrughTbw1G/qg8AXdoBHO/WALYNMmtPVb 0hG1kW0P+O8FJ9kzYhBwkpG5y1sKYZCWbnQz4DRcifVgyKQjE9zLpvHFwwYYAT2KpJYU 62wnD4puBZhQCFafOR89AtRjw1kbxCSx6vLh98Ofs8dYRvfzLtcV+lI8z1XwyI1hAAVt R2hrx21h5w3+rnL6xZaguia+OeSHLgDA0BN2pL1LJkKBj24Pn8AyxzC0pzTyfg1b3Rxv WiYw== X-Forwarded-Encrypted: i=1; AHgh+RpIgmTsEWK0nshbQw2Ptsi/IJ7aLcj2rwxd+nHF/SMs2f4SD8o5wqRuEJgdzFFe4JCiARMWTQ92rklg2KA=@vger.kernel.org X-Gm-Message-State: AOJu0YwM26b2kExwai2LtLxaPWMTRH+murzCSvfbsnbOpHeVlf1WC16R 9xy2++KLyctMqmcpjbRguiIlzKxExeR1Hm9JOdX5RBOIz/oDphx2qTh/ X-Gm-Gg: AfdE7cl5IgN1pWbv5gK/PsuY8fL2zokO3WcDLYItREBMBedsnKR7pYZoLCh64F8SxUb ppT81Jt44cXV0JiaCwHZ/NZ95IrtvR7Qaz9zd2PDhdFBwdgR3H4Jcl9SmB+ITMaNeiQV7I9cs9H 9YL8uSSsmB85YKo3jnTzGycq6OXNsgBZw/3pvc2OoD5MzI4AoYDaSK1gMiXMySrjJrQA0KCKwov Q6+Bmx0ZouHpaEVBI4s5Ck/IX5OjruJSLZRG65JiNVONlbh81NxsoWyVJbA74k1+NhxgQarCcOz uDFyTyck9BNZzqgkBchdDn2py6i1M7O0kV6v6fo+vkXZFZlkeyktbKoy5G6qkL4BT3udjri7XTG H8x/n3h7hrn4YA84GHuMj1V9IBu43f/OZERQbjgqNPFjWqsO13Dgk7jAjuXA1X9elRQGq1vk+FW B6FUGVzqyZvYRvl39QnTdAcMRF X-Received: by 2002:a05:6000:3110:b0:46f:1b89:999 with SMTP id ffacd0b85a97d-46f1b890a94mr16268450f8f.30.1782718116866; Mon, 29 Jun 2026 00:28:36 -0700 (PDT) Received: from foxbook (bgu190.neoplus.adsl.tpnet.pl. [83.28.84.190]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-46d86960983sm40122019f8f.4.2026.06.29.00.28.35 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Mon, 29 Jun 2026 00:28:36 -0700 (PDT) Date: Mon, 29 Jun 2026 09:28:32 +0200 From: Michal Pecio To: "Vlastimil Babka (SUSE)" Cc: sanan.hasanou@gmail.com, vbabka@suse.cz, akpm@linux-foundation.org, cl@gentwo.org, rientjes@google.com, roman.gushchin@linux.dev, harry.yoo@oracle.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, syzkaller@googlegroups.com, contact@pgazz.com, Greg Kroah-Hartman , linux-usb@vger.kernel.org, Mauro Carvalho Chehab , linux-media@vger.kernel.org, Dinghao Liu Subject: Re: WARNING in usb_free_urb Message-ID: <20260629092832.355327e7.michal.pecio@gmail.com> In-Reply-To: <20260629092033.4a83e91b.michal.pecio@gmail.com> References: <6a3eeead.7fb353d3.354599.b0b0@mx.google.com> <85cf5045-b52b-4aaa-a038-ca1b856b55f9@kernel.org> <20260629092033.4a83e91b.michal.pecio@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 29 Jun 2026 09:20:33 +0200, Michal Pecio wrote: > The free(buf[i]) loop should simply be removed. It was mistakenly > added by d571b592c6206, then a26efd1961a18 recognized the double free > but attempted to fix it only by changing the order of freeing. Sent > from .edu domain, so probably an automatic static analyzer fix... Correction: it failed to recognize the double free, but it fixed a different (real) problem that the buf array itself was already NULL and couldn't be scanned for buffer pointers to free. So it turned this NULL dereferenc into a double free.