From: Vasily Averin vvs@virtuozzo.com
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 vvs@virtuozzo.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/netfilter/x_tables.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -1556,6 +1556,9 @@ static void *xt_mttg_seq_next(struct seq 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 default: return NULL; } - - if (ppos != NULL) - ++*ppos; return trav; }