From: Vasily Averin <vvs@virtuozzo.com>
Date: Thu, 23 Jan 2020 07:11:13 +0000 (+0300)
Subject: l2t_seq_next should increase position index
X-Git-Tag: v4.19.102~5
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3239d4b4c2224a7cc4020ea99a9b331ecf9fab4c;p=thirdparty%2Fkernel%2Fstable.git

l2t_seq_next should increase position index

[ Upstream commit 66018a102f7756cf72db4d2704e1b93969d9d332 ]

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 <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/net/ethernet/chelsio/cxgb4/l2t.c b/drivers/net/ethernet/chelsio/cxgb4/l2t.c
index 301c4df8a5664..986277744611c 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/l2t.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/l2t.c
@@ -683,8 +683,7 @@ static void *l2t_seq_start(struct seq_file *seq, loff_t *pos)
 static void *l2t_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	v = l2t_get_idx(seq, *pos);
-	if (v)
-		++*pos;
+	++(*pos);
 	return v;
 }