From patchwork Mon Aug 12 12:11:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Yi X-Patchwork-Id: 13760489 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 7784217B512; Mon, 12 Aug 2024 12:16:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723464987; cv=none; b=CAiZQcPbxCrXFXTGbc7MI/Vo3QD8tMOCdA84cpG+oktldgDeO6L3t5Zo80+v72IobDum3Yv3sGxx4lbbhUgZMjWHqp1amEp2XxraPaYt8u19tRf0snm3Vq00+WsXL+B35m1VY/BxsWJKc7Z5GOl5KIkGzhBitcE13MWdkxjPBus= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723464987; c=relaxed/simple; bh=qwwFYGMWC22LSZVs7J52wbNCW10XLQrjH2GIDCGBkBQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=orhGq+XB8l2exQMtO3J+mnb+txOmgJH6fE+40qwPBWlmUmCB/iSgLhIHF8xWHJZIJSWJXuz7w1NNlvuFBlNfJS0Qo2u5WXqOPrO5bO0nxKCatsjMZPSxpChtsxKkU/A+GWhQVTHFXJlPQ+F+9DmogSdH/cffqK7XMRxSizFvtpc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.216]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4WjD534627z4f3kKT; Mon, 12 Aug 2024 20:16:07 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.252]) by mail.maildlp.com (Postfix) with ESMTP id CAFA01A1537; Mon, 12 Aug 2024 20:16:16 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP3 (Coremail) with SMTP id _Ch0CgDHeLcD_blmHhy7BQ--.21435S9; Mon, 12 Aug 2024 20:16:13 +0800 (CST) From: Zhang Yi To: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, djwong@kernel.org, hch@infradead.org, brauner@kernel.org, david@fromorbit.com, jack@suse.cz, willy@infradead.org, yi.zhang@huawei.com, yi.zhang@huaweicloud.com, chengzhihao1@huawei.com, yukuai3@huawei.com Subject: [PATCH v2 5/6] iomap: don't mark blocks uptodate after partial zeroing Date: Mon, 12 Aug 2024 20:11:58 +0800 Message-Id: <20240812121159.3775074-6-yi.zhang@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240812121159.3775074-1-yi.zhang@huaweicloud.com> References: <20240812121159.3775074-1-yi.zhang@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: _Ch0CgDHeLcD_blmHhy7BQ--.21435S9 X-Coremail-Antispam: 1UD129KBjvJXoW7Kr4UKryxCF1fXryfXF4ruFg_yoW8GFWDpF Z8KFWkKryqgF43u3WkAF93Zw10ya90gr4fCr4UWwn8uF45tF4jgr92ga13ZFy0vry7Cr4Y vr4vgFy8uF15ZrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmI14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUGVWUXwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67 AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI 42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCw CI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnI WIevJa73UjIFyTuYvjfUriihUUUUU X-CM-SenderInfo: d1lo6xhdqjqx5xdzvxpfor3voofrz/ From: Zhang Yi In __iomap_write_begin(), if we unaligned buffered write data to a hole of a regular file, we only zero out the place where aligned to block size that we don't want to write, but mark the whole range uptodate if block size < folio size. This is wrong since the not zeroed part will contains stale data and can be accessed by a concurrent buffered read easily (on the filesystem may not hold inode->i_rwsem) once we mark the range uptodate. Fix this by drop iomap_set_range_uptodate() in the zeroing out branch. Fixes: 9dc55f1389f9 ("iomap: add support for sub-pagesize buffered I/O without buffer heads") Reported-by: Matthew Wilcox Closes: https://lore.kernel.org/all/ZqsN5ouQTEc1KAzV@casper.infradead.org/ Signed-off-by: Zhang Yi Reviewed-by: Christoph Hellwig --- fs/iomap/buffered-io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index ac762de9a27f..96600405dbb5 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -744,8 +744,8 @@ static int __iomap_write_begin(const struct iomap_iter *iter, loff_t pos, poff, plen, srcmap); if (status) return status; + iomap_set_range_uptodate(folio, poff, plen); } - iomap_set_range_uptodate(folio, poff, plen); } while ((block_start += plen) < block_end); return 0;