From 8b101a5e14f2161869636ff9cb4907b7749dc0c2 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Fri, 24 Jan 2020 08:48:55 +0300 Subject: s390/cio: cio_ignore_proc_seq_next should increase position index if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Link: https://lore.kernel.org/r/d44c53a7-9bc1-15c7-6d4a-0c10cb9dffce@virtuozzo.com Reviewed-by: Cornelia Huck Signed-off-by: Christian Borntraeger Signed-off-by: Vasily Averin Signed-off-by: Vasily Gorbik --- drivers/s390/cio/blacklist.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/s390/cio') diff --git a/drivers/s390/cio/blacklist.c b/drivers/s390/cio/blacklist.c index da642e811f7f..4dd2eb634856 100644 --- a/drivers/s390/cio/blacklist.c +++ b/drivers/s390/cio/blacklist.c @@ -303,8 +303,10 @@ static void * 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 @@ cio_ignore_proc_seq_next(struct seq_file *s, void *it, loff_t *offset) return NULL; } else iter->devno++; - (*offset)++; return iter; } -- cgit v1.2.3-59-g8ed1b