/*
 * net/sched/em_ipset.c	ipset ematch
 *
 * Copyright (c) 2012 Florian Westphal <fw@strlen.de>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 */

#include <linux/gfp.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/netfilter/xt_set.h>
#include <linux/ipv6.h>
#include <net/ip.h>
#include <net/pkt_cls.h>

static int em_ipset_change(struct net *net, void *data, int data_len,
			   struct tcf_ematch *em)
{
	struct xt_set_info *set = data;
	ip_set_id_t index;

	if (data_len != sizeof(*set))
		return -EINVAL;

	index = ip_set_nfnl_get_byindex(net, set->index);
	if (index == IPSET_INVALID_ID)
		return -ENOENT;

	em->datalen = sizeof(*set);
	em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL);
	if (em->data)
		return 0;

	ip_set_nfnl_put(net, index);
	return -ENOMEM;
}

static void em_ipset_destroy(struct tcf_ematch *em)
{
	const struct xt_set_info *set = (const void *) em->data;
	if (set) {
		ip_set_nfnl_put(em->net, set->index);
		kfree((void *) em->data);
	}
}

static int em_ipset_match(struct sk_buff *skb, struct tcf_ematch *em,
			  struct tcf_pkt_info *info)
{
	struct ip_set_adt_opt opt;
	struct xt_action_param acpar;
	const struct xt_set_info *set = (const void *) em->data;
	struct net_device *dev, *indev = NULL;
	struct nf_hook_state state = {
		.net	= em->net,
	};
	int ret, network_offset;

	switch (tc_skb_protocol(skb)) {
	case htons(ETH_P_IP):
		state.pf = NFPROTO_IPV4;
		if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
			return 0;
		acpar.thoff = ip_hdrlen(skb);
		break;
	case htons(ETH_P_IPV6):
		state.pf = NFPROTO_IPV6;
		if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
			return 0;
		/* doesn't call ipv6_find_hdr() because ipset doesn't use thoff, yet */
		acpar.thoff = sizeof(struct ipv6hdr);
		break;
	default:
		return 0;
	}

	opt.family = state.pf;
	opt.dim = set->dim;
	opt.flags = set->flags;
	opt.cmdflags = 0;
	opt.ext.timeout = ~0u;

	network_offset = skb_network_offset(skb);
	skb_pull(skb, network_offset);

	dev = skb->dev;

	rcu_read_lock();

	if (skb->skb_iif)
		indev = dev_get_by_index_rcu(em->net, skb->skb_iif);

	state.in      = indev ? indev : dev;
	state.out     = dev;
	acpar.state   = &state;

	ret = ip_set_test(set->index, skb, &acpar, &opt);

	rcu_read_unlock();

	skb_push(skb, network_offset);
	return ret;
}

static struct tcf_ematch_ops em_ipset_ops = {
	.kind	  = TCF_EM_IPSET,
	.change	  = em_ipset_change,
	.destroy  = em_ipset_destroy,
	.match	  = em_ipset_match,
	.owner	  = THIS_MODULE,
	.link	  = LIST_HEAD_INIT(em_ipset_ops.link)
};

static int __init init_em_ipset(void)
{
	return tcf_em_register(&em_ipset_ops);
}

static void __exit exit_em_ipset(void)
{
	tcf_em_unregister(&em_ipset_ops);
}

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
MODULE_DESCRIPTION("TC extended match for IP sets");

module_init(init_em_ipset);
module_exit(exit_em_ipset);

MODULE_ALIAS_TCF_EMATCH(TCF_EM_IPSET);
</a>/<a href='/cgit.cgi/linux/net-next.git/commit/sound/soc/codecs/tlv320aic31xx.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>tlv320aic31xx.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='91539eb1fda2d530d3b268eef542c5414e54bf1a'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Iago Abal &lt;mail@iagoabal.eu&gt;</td><td class='right'>2017-01-11 14:00:21 +0100</td></tr>
<tr><th>committer</th><td>Vinod Koul &lt;vinod.koul@intel.com&gt;</td><td class='right'>2017-01-25 15:35:11 +0530</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc/codecs/tlv320aic31xx.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/sound/soc/codecs/tlv320aic31xx.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>960f5ca6342ad20837aff18aad6e8ecd7da32fd6</a> /<a href='/cgit.cgi/linux/net-next.git/tree/sound/soc/codecs/tlv320aic31xx.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>sound/soc/codecs/tlv320aic31xx.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc/codecs/tlv320aic31xx.c?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc/codecs/tlv320aic31xx.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a&amp;id2=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>diff</a>)</td></tr></table>
<div class='commit-subject'>dmaengine: pl330: fix double lock</div><div class='commit-msg'>The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the
following double-lock bug:

    Double lock:
    1. spin_lock_irqsave(pch-&gt;lock, flags) at pl330_free_chan_resources:2236;
    2. call to function `pl330_release_channel' immediately after;
    3. call to function `dma_pl330_rqcb' in line 1753;
    4. spin_lock_irqsave(pch-&gt;lock, flags) at dma_pl330_rqcb:1505.

I have fixed it as suggested by Marek Szyprowski.

First, I have replaced `pch-&gt;lock' with `pl330-&gt;lock' in functions
`pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids
the double-lock by acquiring a different lock than `dma_pl330_rqcb'.

NOTE that, as a result, `pl330_free_chan_resources' executes
`list_splice_tail_init' on `pch-&gt;work_list' under lock `pl330-&gt;lock',
whereas in the rest of the code `pch-&gt;work_list' is protected by
`pch-&gt;lock'. I don't know if this may cause race conditions. Similarly
`pch-&gt;cyclic' is written by `pl330_alloc_chan_resources' under
`pl330-&gt;lock' but read by `pl330_tx_submit' under `pch-&gt;lock'.

Second, I have removed locking from `pl330_request_channel' and
`pl330_release_channel' functions. Function `pl330_request_channel' is
only called from `pl330_alloc_chan_resources', so the lock is already
held. Function `pl330_release_channel' is called from
`pl330_free_chan_resources', which already holds the lock, and from
`pl330_del'. Function `pl330_del' is called in an error path of
`pl330_probe' and at the end of `pl330_remove', but I assume that there
cannot be concurrent accesses to the protected data at those points.

Signed-off-by: Iago Abal &lt;mail@iagoabal.eu&gt;
Reviewed-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Vinod Koul &lt;vinod.koul@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>Diffstat</a> (limited to 'sound/soc/codecs/tlv320aic31xx.c')</div><table summary='diffstat' class='diffstat'>