From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 D714E23C8CD for ; Thu, 13 Nov 2025 13:57:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763042266; cv=none; b=RpiQ2Ecva6FdWMJmGj+FKhrUouoGAdmHOV/eNlBIqr21T0joC4lRhhVe4xcx7ovr1cYS5rFChWZc6rJXSzS+n9v38hRGwTF/LErZl9tUv8eXbmRkxNipHTiFUnEH6pM9WIjwfxXiwIJ0jVrsq73KK/wGwc/jCN/1kDrRznlurgI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763042266; c=relaxed/simple; bh=JLeLFFZYZwY6fpyJMEn28rycTYvDbk94qpZ/GmXSaCk=; h=From:In-Reply-To:References:To:Cc:Subject:MIME-Version: Content-Type:Date:Message-ID; b=Mr4gcr95FXkxUMEGOWfZa2LQozIVM/dhUhMQudMunFVzAbBRULtntm6GATvoYikpL1iOxU+MMZhC5ekl+YCYZeH4G9WZC/gbw1M/DTok5D3OsGrJ9OnAat42vJCbRgzo86Jo8rZczeXf+3KEfVes2HBM8/GRbOm3SzaaDIMAq/s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine 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=bSYr8Byn; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine 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="bSYr8Byn" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1763042263; 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=NGLKxXQF0F/XWTApJ0iL6QP8bi29GckGnnFKci2qgBI=; b=bSYr8BynPRWutWyIKa2IG2lQaihhMAWcvEk0Mgnc0xSX32rpIbR/mSNgFIMH5sZeDOOCQG SVjinlJ/jTb2gddSWfPTn2fsZmO/oz3U3QekpOFVX2WBzwn5ZVtyivUdaCSMdbb6t0zWh4 neF0OeJ3QpgOkkaHaU8rcHqlS9c+Y4o= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-683-sp60RIDPOj29y3R-3xX3ng-1; Thu, 13 Nov 2025 08:57:37 -0500 X-MC-Unique: sp60RIDPOj29y3R-3xX3ng-1 X-Mimecast-MFC-AGG-ID: sp60RIDPOj29y3R-3xX3ng_1763042256 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E71201801235; Thu, 13 Nov 2025 13:57:35 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.87]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 2BF13180097D; Thu, 13 Nov 2025 13:57:32 +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: References: <36fb31bf2c854cdc930a3415f5551dcd@izw-berlin.de> <958479.1762852948@warthog.procyon.org.uk> <1392200.1762971247@warthog.procyon.org.uk> To: Shyam Prasad N Cc: dhowells@redhat.com, Bharath SM , Mark A Whiting , henrique.carvalho@suse.com, Enzo Matsumiya , Steve French , Paulo Alcantara , "Heckmann, Ilja" , "linux-cifs@vger.kernel.org" Subject: Re: [[ EXT ]] [BUG REPORT] cifs/smb data corruption when writing, x86_64, kernel 6.6.71 Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <1640438.1763042251.1@warthog.procyon.org.uk> Date: Thu, 13 Nov 2025 13:57:31 +0000 Message-ID: <1640439.1763042251@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Shyam Prasad N wrote: > + > + /* boundary check before the folio is accounted */ > + if ((max_pages - nr_pages) <= 0 || > + (*_len + len) >= max_len || > + (*_count - nr_pages) <= 0) { > + folio_unlock(folio); > + folio_put(folio); > + xas_reset(xas); > + break; > + } > + I suspect that whilst this will work, it will mean that you can never append a partial page to a write op; a partial page will always have to start a new RPC call. So if you do: fd = open("/cifs/foo"); write(fd, buf, 0x1001); close(fd); it will make two Write ops, one for 4K and one for 1 byte (give or take PAGE_SIZE==4096). David