From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sw.ru ([185.231.240.75]:50864 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730247AbgAXFtC (ORCPT ); Fri, 24 Jan 2020 00:49:02 -0500 From: Vasily Averin Subject: [PATCH 1/1] cio_ignore_proc_seq_next should increase position index Message-ID: Date: Fri, 24 Jan 2020 08:48:55 +0300 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: linux-s390@vger.kernel.org Cc: Sebastian Ott , Peter Oberparleiter , Heiko Carstens , Vasily Gorbik , Christian Borntraeger if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin --- drivers/s390/cio/blacklist.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/s390/cio/blacklist.c b/drivers/s390/cio/blacklist.c index 2a3f874..9cebff8 100644 --- a/drivers/s390/cio/blacklist.c +++ b/drivers/s390/cio/blacklist.c @@ -303,8 +303,10 @@ struct ccwdev_iter { cio_ignore_proc_seq_next(struct seq_file *s, void *it, loff_t *offset) { struct ccwdev_iter *iter; + loff_t p = *offset; - if (*offset >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1)) + (*offset)++; + if (p >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1)) return NULL; iter = it; if (iter->devno == __MAX_SUBCHANNEL) { @@ -314,7 +316,6 @@ struct ccwdev_iter { return NULL; } else iter->devno++; - (*offset)++; return iter; } -- 1.8.3.1