/* xfrm4_tunnel.c: Generic IP tunnel transformer.
 *
 * Copyright (C) 2003 David S. Miller (davem@redhat.com)
 */

#define pr_fmt(fmt) "IPsec: " fmt

#include <linux/skbuff.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <net/xfrm.h>
#include <net/ip.h>
#include <net/protocol.h>

static int ipip_output(struct xfrm_state *x, struct sk_buff *skb)
{
	skb_push(skb, -skb_network_offset(skb));
	return 0;
}

static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb)
{
	return ip_hdr(skb)->protocol;
}

static int ipip_init_state(struct xfrm_state *x)
{
	if (x->props.mode != XFRM_MODE_TUNNEL)
		return -EINVAL;

	if (x->encap)
		return -EINVAL;

	x->props.header_len = sizeof(struct iphdr);

	return 0;
}

static void ipip_destroy(struct xfrm_state *x)
{
}

static const struct xfrm_type ipip_type = {
	.description	= "IPIP",
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_IPIP,
	.init_state	= ipip_init_state,
	.destructor	= ipip_destroy,
	.input		= ipip_xfrm_rcv,
	.output		= ipip_output
};

static int xfrm_tunnel_rcv(struct sk_buff *skb)
{
	return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr);
}

static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
{
	return -ENOENT;
}

static struct xfrm_tunnel xfrm_tunnel_handler __read_mostly = {
	.handler	=	xfrm_tunnel_rcv,
	.err_handler	=	xfrm_tunnel_err,
	.priority	=	3,
};

#if IS_ENABLED(CONFIG_IPV6)
static struct xfrm_tunnel xfrm64_tunnel_handler __read_mostly = {
	.handler	=	xfrm_tunnel_rcv,
	.err_handler	=	xfrm_tunnel_err,
	.priority	=	2,
};
#endif

static int __init ipip_init(void)
{
	if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
		pr_info("%s: can't add xfrm type\n", __func__);
		return -EAGAIN;
	}

	if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) {
		pr_info("%s: can't add xfrm handler for AF_INET\n", __func__);
		xfrm_unregister_type(&ipip_type, AF_INET);
		return -EAGAIN;
	}
#if IS_ENABLED(CONFIG_IPV6)
	if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) {
		pr_info("%s: can't add xfrm handler for AF_INET6\n", __func__);
		xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET);
		xfrm_unregister_type(&ipip_type, AF_INET);
		return -EAGAIN;
	}
#endif
	return 0;
}

static void __exit ipip_fini(void)
{
#if IS_ENABLED(CONFIG_IPV6)
	if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6))
		pr_info("%s: can't remove xfrm handler for AF_INET6\n",
			__func__);
#endif
	if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET))
		pr_info("%s: can't remove xfrm handler for AF_INET\n",
			__func__);
	if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
		pr_info("%s: can't remove xfrm type\n", __func__);
}

module_init(ipip_init);
module_exit(ipip_fini);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_IPIP);
href='/cgit.cgi/linux/net-next.git/commit/net?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>net</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net/mac80211?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>mac80211</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net/mac80211/ethtool.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>ethtool.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/net/mac80211/ethtool.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/mac80211/ethtool.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/net/mac80211/ethtool.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>net/mac80211/ethtool.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/mac80211/ethtool.c?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/mac80211/ethtool.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 'net/mac80211/ethtool.c')</div><table summary='diffstat' class='diffstat'>