Commit 8b101a5e authored Jan 24, 2020 by Vasily Averin Committed by Vasily Gorbik Feb 17, 2020

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 <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

parent 11a48a5a

drivers/s390/cio/blacklist.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -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;
		}

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