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Revision 916f6efae62305796e012e7c3a7884a267cbacbf authored by Florian Westphal on 17 April 2019, 00:17:23 UTC, committed by Pablo Neira Ayuso on 22 April 2019, 08:34:30 UTC 
netfilter: never get/set skb->tstamp
 
setting net.netfilter.nf_conntrack_timestamp=1 breaks xmit with fq
scheduler.  skb->tstamp might be "refreshed" using ktime_get_real(),
but fq expects CLOCK_MONOTONIC.

This patch removes all places in netfilter that check/set skb->tstamp:

1. To fix the bogus "start" time seen with conntrack timestamping for
   outgoing packets, never use skb->tstamp and always use current time.
2. In nfqueue and nflog, only use skb->tstamp for incoming packets,
   as determined by current hook (prerouting, input, forward).
3. xt_time has to use system clock as well rather than skb->tstamp.
   We could still use skb->tstamp for prerouting/input/foward, but
   I see no advantage to make this conditional.

Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC")
Cc: Eric Dumazet <edumazet@google.com>
Reported-by: Michal Soltys <soltys@ziu.info>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1 parent 7caa56f
Raw File
consoles.c 
/*
 * Copyright (c) 2010 Werner Fink, Jiri Slaby
 *
 * Licensed under GPLv2
 */

#include <linux/console.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/tty_driver.h>

/*
 * This is handler for /proc/consoles
 */
static int show_console_dev(struct seq_file *m, void *v)
{
	static const struct {
		short flag;
		char name;
	} con_flags[] = {
		{ CON_ENABLED,		'E' },
		{ CON_CONSDEV,		'C' },
		{ CON_BOOT,		'B' },
		{ CON_PRINTBUFFER,	'p' },
		{ CON_BRL,		'b' },
		{ CON_ANYTIME,		'a' },
	};
	char flags[ARRAY_SIZE(con_flags) + 1];
	struct console *con = v;
	unsigned int a;
	dev_t dev = 0;

	if (con->device) {
		const struct tty_driver *driver;
		int index;
		driver = con->device(con, &index);
		if (driver) {
			dev = MKDEV(driver->major, driver->minor_start);
			dev += index;
		}
	}

	for (a = 0; a < ARRAY_SIZE(con_flags); a++)
		flags[a] = (con->flags & con_flags[a].flag) ?
			con_flags[a].name : ' ';
	flags[a] = 0;

	seq_setwidth(m, 21 - 1);
	seq_printf(m, "%s%d", con->name, con->index);
	seq_pad(m, ' ');
	seq_printf(m, "%c%c%c (%s)", con->read ? 'R' : '-',
			con->write ? 'W' : '-', con->unblank ? 'U' : '-',
			flags);
	if (dev)
		seq_printf(m, " %4d:%d", MAJOR(dev), MINOR(dev));

	seq_putc(m, '\n');
	return 0;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
	struct console *con;
	loff_t off = 0;

	console_lock();
	for_each_console(con)
		if (off++ == *pos)
			break;

	return con;
}

static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct console *con = v;
	++*pos;
	return con->next;
}

static void c_stop(struct seq_file *m, void *v)
{
	console_unlock();
}

static const struct seq_operations consoles_op = {
	.start	= c_start,
	.next	= c_next,
	.stop	= c_stop,
	.show	= show_console_dev
};

static int __init proc_consoles_init(void)
{
	proc_create_seq("consoles", 0, NULL, &consoles_op);
	return 0;
}
fs_initcall(proc_consoles_init);
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