From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6CD5B1C244C for ; Thu, 10 Oct 2024 11:26:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728559583; cv=none; b=F0YoMwaBEafWl8b4M+lkOj2p0RuQNlqZsoIYvegGWu0x9nUYTzCOqAa2v8YG44JEhZh7ZaNmR5ufisR0Oa2SWEYlQh3x1r6mhAmvavfj1zic/Tp6gJ1Cufi3s1Jcrp6Mavds9wBb9PuD0MSA5RlMuO0QeTPU5TIwqYsjRAkSmjU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728559583; c=relaxed/simple; bh=10vTDP77W6iT8wnZVG2NLG1W63L7dkmUAZsW2OhEe4U=; h=From:In-Reply-To:References:To:Cc:Subject:MIME-Version: Content-Type:Date:Message-ID; b=BKYhX/S9f1gnVGx3QB2DPxzLT4J1iOR8JtwfAt19x1qzz0mkAJl6JWwksFPJ7g6xs4WclAtqRNvoTgo3tre/lCp7fF8H8oGUg6T8Z+eM2n7YMhz69682mYiikSW7Nt214JAkYZsa4/1p+r6BeIECFaJsIWlth/LOR0kcc3yoaNY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=iMG4T2v9; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iMG4T2v9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1728559581; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=NJUmRu+1qjEf0r4E7oHDRAPSAR+s1Bygz5pulK3ypfw=; b=iMG4T2v9oHulacvixv5FuXQsxmUnqQZ/nRBc4BZobltVPggOlZlIxItM5WmXWfwWkOKL43 XO4VWkOxxwp7gaOH2XeR4BQW2hTATyS5B3F1dHEKHvdmbeZI0hIh1xCI99ehkWStKY6dOX /TgViHnhZtavHib1ENta6auYUyP6ldo= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-646-NFOnjL-PMtKPIBAhYDEK-w-1; Thu, 10 Oct 2024 07:26:18 -0400 X-MC-Unique: NFOnjL-PMtKPIBAhYDEK-w-1 Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id DD0E419560A2; Thu, 10 Oct 2024 11:26:15 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.4]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id B56781956086; Thu, 10 Oct 2024 11:26:07 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20240821024301.1058918-8-wozizhi@huawei.com> References: <20240821024301.1058918-8-wozizhi@huawei.com> <20240821024301.1058918-1-wozizhi@huawei.com> To: Zizhi Wo Cc: dhowells@redhat.com, netfs@lists.linux.dev, jlayton@kernel.org, hsiangkao@linux.alibaba.com, jefflexu@linux.alibaba.com, zhujia.zj@bytedance.com, linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, libaokun1@huawei.com, yangerkun@huawei.com, houtao1@huawei.com, yukuai3@huawei.com Subject: Re: [PATCH 7/8] cachefiles: Fix NULL pointer dereference in object->file Precedence: bulk X-Mailing-List: netfs@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <303976.1728559565.1@warthog.procyon.org.uk> Date: Thu, 10 Oct 2024 12:26:05 +0100 Message-ID: <303977.1728559565@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 Zizhi Wo wrote: > + spin_lock(&object->lock); > if (object->file) { > fput(object->file); > object->file = NULL; > } > + spin_unlock(&object->lock); I would suggest stashing the file pointer in a local var and then doing the fput() outside of the locks. David