/*
 * net/sched/em_nbyte.c	N-Byte ematch
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Thomas Graf <tgraf@suug.ch>
 */

#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/tc_ematch/tc_em_nbyte.h>
#include <net/pkt_cls.h>

struct nbyte_data {
	struct tcf_em_nbyte	hdr;
	char			pattern[0];
};

static int em_nbyte_change(struct net *net, void *data, int data_len,
			   struct tcf_ematch *em)
{
	struct tcf_em_nbyte *nbyte = data;

	if (data_len < sizeof(*nbyte) ||
	    data_len < (sizeof(*nbyte) + nbyte->len))
		return -EINVAL;

	em->datalen = sizeof(*nbyte) + nbyte->len;
	em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL);
	if (em->data == 0UL)
		return -ENOBUFS;

	return 0;
}

static int em_nbyte_match(struct sk_buff *skb, struct tcf_ematch *em,
			  struct tcf_pkt_info *info)
{
	struct nbyte_data *nbyte = (struct nbyte_data *) em->data;
	unsigned char *ptr = tcf_get_base_ptr(skb, nbyte->hdr.layer);

	ptr += nbyte->hdr.off;

	if (!tcf_valid_offset(skb, ptr, nbyte->hdr.len))
		return 0;

	return !memcmp(ptr + nbyte->hdr.off, nbyte->pattern, nbyte->hdr.len);
}

static struct tcf_ematch_ops em_nbyte_ops = {
	.kind	  = TCF_EM_NBYTE,
	.change	  = em_nbyte_change,
	.match	  = em_nbyte_match,
	.owner	  = THIS_MODULE,
	.link	  = LIST_HEAD_INIT(em_nbyte_ops.link)
};

static int __init init_em_nbyte(void)
{
	return tcf_em_register(&em_nbyte_ops);
}

static void __exit exit_em_nbyte(void)
{
	tcf_em_unregister(&em_nbyte_ops);
}

MODULE_LICENSE("GPL");

module_init(init_em_nbyte);
module_exit(exit_em_nbyte);

MODULE_ALIAS_TCF_EMATCH(TCF_EM_NBYTE);
t-next.git/diff/?id=c020d722b110a44c613ef71e657e6dd4116e09d9'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/'>
<input type='hidden' name='id' value='c020d722b110a44c613ef71e657e6dd4116e09d9'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='c020d722b110a44c613ef71e657e6dd4116e09d9'/><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>Stefan Haberland &lt;sth@linux.vnet.ibm.com&gt;</td><td class='right'>2016-09-20 10:42:38 +0200</td></tr>
<tr><th>committer</th><td>Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;</td><td class='right'>2016-09-26 16:45:29 +0200</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=c020d722b110a44c613ef71e657e6dd4116e09d9'>c020d722b110a44c613ef71e657e6dd4116e09d9</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=c020d722b110a44c613ef71e657e6dd4116e09d9'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=c020d722b110a44c613ef71e657e6dd4116e09d9'>5fc0f6d62335cb7075f6a162380ee54c1b3ea069</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=a9f6273ff9c80dd2c226f7a2d5c16272e5092d3e'>a9f6273ff9c80dd2c226f7a2d5c16272e5092d3e</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=c020d722b110a44c613ef71e657e6dd4116e09d9&amp;id2=a9f6273ff9c80dd2c226f7a2d5c16272e5092d3e'>diff</a>)</td></tr></table>
<div class='commit-subject'>s390/dasd: fix panic during offline processing</div><div class='commit-msg'>A DASD device consists of the device itself and a discipline with a
corresponding private structure. These fields are set up during online
processing right after the device is created and before it is processed by
the state machine and made available for I/O.
During offline processing the discipline pointer and the private data gets
freed within the state machine and without protection of the existing
reference count. This might lead to a kernel panic because a function might
have taken a device reference and accesses the discipline pointer and/or
private data of the device while this is already freed.

Fix by freeing the discipline pointer and the private data after ensuring
that there is no reference to the device left.

Reviewed-by: Peter Oberparleiter &lt;oberpar@linux.vnet.ibm.com&gt;
Signed-off-by: Stefan Haberland &lt;sth@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=c020d722b110a44c613ef71e657e6dd4116e09d9'>Diffstat</a></div><table summary='diffstat' class='diffstat'>