From 80a12a6f03577de7077a04705b2eeb8078653816 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Tue, 25 Feb 2020 10:07:12 +0300 Subject: [PATCH] netfilter: x_tables: xt_mttg_seq_next should increase position index commit ee84f19cbbe9cf7cba2958acb03163fed3ecbb0f upstream. If .next function does not change position index, following .show function will repeat output related to current position index. Without patch: # dd if=/proc/net/ip_tables_matches # original file output conntrack conntrack conntrack recent recent icmp udplite udp tcp 0+1 records in 0+1 records out 65 bytes copied, 5.4074e-05 s, 1.2 MB/s # dd if=/proc/net/ip_tables_matches bs=62 skip=1 dd: /proc/net/ip_tables_matches: cannot skip to specified offset cp <<< end of last line tcp <<< and then unexpected whole last line once again 0+1 records in 0+1 records out 7 bytes copied, 0.000102447 s, 68.3 kB/s Cc: stable@vger.kernel.org Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/x_tables.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index 13e1ac3..3bab89d 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -1556,6 +1556,9 @@ static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos, uint8_t nfproto = (unsigned long)PDE_DATA(file_inode(seq->file)); struct nf_mttg_trav *trav = seq->private; + if (ppos != NULL) + ++(*ppos); + switch (trav->class) { case MTTG_TRAV_INIT: trav->class = MTTG_TRAV_NFP_UNSPEC; @@ -1581,9 +1584,6 @@ static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos, default: return NULL; } - - if (ppos != NULL) - ++*ppos; return trav; } -- 2.7.4