Revision 9e2b7fa2df4365e99934901da4fb4af52d81e820 authored by Martin Willi on 06 November 2020, 07:30:30 UTC, committed by Jakub Kicinski on 12 November 2020, 15:47:06 UTC
VRF devices use an optimized direct path on output if a default qdisc
is involved, calling Netfilter hooks directly. This path, however, does
not consider Netfilter rules completing asynchronously, such as with
NFQUEUE. The Netfilter okfn() is called for asynchronously accepted
packets, but the VRF never passes that packet down the stack to send
it out over the slave device. Using the slower redirect path for this
seems not feasible, as we do not know beforehand if a Netfilter hook
has asynchronously completing rules.

Fix the use of asynchronously completing Netfilter rules in OUTPUT and
POSTROUTING by using a special completion function that additionally
calls dst_output() to pass the packet down the stack. Also, slightly
adjust the use of nf_reset_ct() so that is called in the asynchronous
case, too.

Fixes: dcdd43c41e60 ("net: vrf: performance improvements for IPv4")
Fixes: a9ec54d1b0cd ("net: vrf: performance improvements for IPv6")
Signed-off-by: Martin Willi <martin@strongswan.org>
Link: https://lore.kernel.org/r/20201106073030.3974927-1-martin@strongswan.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1 parent 52755b6
Raw File
tc-driver.c
/*
 *	TURBOchannel driver services.
 *
 *	Copyright (c) 2005  James Simmons
 *	Copyright (c) 2006  Maciej W. Rozycki
 *
 *	Loosely based on drivers/dio/dio-driver.c and
 *	drivers/pci/pci-driver.c.
 *
 *	This file is subject to the terms and conditions of the GNU
 *	General Public License.  See the file "COPYING" in the main
 *	directory of this archive for more details.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/tc.h>

/**
 * tc_register_driver - register a new TC driver
 * @drv: the driver structure to register
 *
 * Adds the driver structure to the list of registered drivers
 * Returns a negative value on error, otherwise 0.
 * If no error occurred, the driver remains registered even if
 * no device was claimed during registration.
 */
int tc_register_driver(struct tc_driver *tdrv)
{
	return driver_register(&tdrv->driver);
}
EXPORT_SYMBOL(tc_register_driver);

/**
 * tc_unregister_driver - unregister a TC driver
 * @drv: the driver structure to unregister
 *
 * Deletes the driver structure from the list of registered TC drivers,
 * gives it a chance to clean up by calling its remove() function for
 * each device it was responsible for, and marks those devices as
 * driverless.
 */
void tc_unregister_driver(struct tc_driver *tdrv)
{
	driver_unregister(&tdrv->driver);
}
EXPORT_SYMBOL(tc_unregister_driver);

/**
 * tc_match_device - tell if a TC device structure has a matching
 *                   TC device ID structure
 * @tdrv: the TC driver to earch for matching TC device ID strings
 * @tdev: the TC device structure to match against
 *
 * Used by a driver to check whether a TC device present in the
 * system is in its list of supported devices.  Returns the matching
 * tc_device_id structure or %NULL if there is no match.
 */
static const struct tc_device_id *tc_match_device(struct tc_driver *tdrv,
						  struct tc_dev *tdev)
{
	const struct tc_device_id *id = tdrv->id_table;

	if (id) {
		while (id->name[0] || id->vendor[0]) {
			if (strcmp(tdev->name, id->name) == 0 &&
			    strcmp(tdev->vendor, id->vendor) == 0)
				return id;
			id++;
		}
	}
	return NULL;
}

/**
 * tc_bus_match - Tell if a device structure has a matching
 *                TC device ID structure
 * @dev: the device structure to match against
 * @drv: the device driver to search for matching TC device ID strings
 *
 * Used by a driver to check whether a TC device present in the
 * system is in its list of supported devices.  Returns 1 if there
 * is a match or 0 otherwise.
 */
static int tc_bus_match(struct device *dev, struct device_driver *drv)
{
	struct tc_dev *tdev = to_tc_dev(dev);
	struct tc_driver *tdrv = to_tc_driver(drv);
	const struct tc_device_id *id;

	id = tc_match_device(tdrv, tdev);
	if (id)
		return 1;

	return 0;
}

struct bus_type tc_bus_type = {
	.name	= "tc",
	.match	= tc_bus_match,
};
EXPORT_SYMBOL(tc_bus_type);

static int __init tc_driver_init(void)
{
	return bus_register(&tc_bus_type);
}

postcore_initcall(tc_driver_init);
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