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[NETFILTER]: ip_tables: compat code module refcounting fix 

This patch fixes bug in iptables modules refcounting on compat error way.

As we are getting modules in check_compat_entry_size_and_hooks(), in case of
later error, we should put them all in translate_compat_table(), not  in the
compat_copy_entry_from_user() or compat_copy_match_from_user(), as it is now.

Signed-off-by: Dmitry Mishin <dim@openvz.org>
Acked-by: Vasily Averin <vvs@openvz.org>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dmitry Mishin 2006-10-30 15:14:27 -08:00 committed by David S. Miller
parent c073e3fa8b
commit 920b868ae1
1 changed files with 11 additions and 25 deletions
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36
net/ipv4/netfilter/ip_tables.c
View File

@ -1527,7 +1527,7 @@ cleanup_matches:
static inline int compat_copy_match_from_user(struct ipt_entry_match *m,
void **dstptr, compat_uint_t *size, const char *name,
const struct ipt_ip *ip, unsigned int hookmask, int *i)
const struct ipt_ip *ip, unsigned int hookmask)
{
struct ipt_entry_match *dm;
struct ipt_match *match;
@ -1540,22 +1540,13 @@ static inline int compat_copy_match_from_user(struct ipt_entry_match *m,
ret = xt_check_match(match, AF_INET, dm->u.match_size - sizeof(*dm),
name, hookmask, ip->proto,
ip->invflags & IPT_INV_PROTO);
if (ret)
goto err;
if (m->u.kernel.match->checkentry
if (!ret && m->u.kernel.match->checkentry
&& !m->u.kernel.match->checkentry(name, ip, match, dm->data,
hookmask)) {
duprintf("ip_tables: check failed for `%s'.\n",
m->u.kernel.match->name);
ret = -EINVAL;
goto err;
}
(*i)++;
return 0;
err:
module_put(m->u.kernel.match->me);
return ret;
}
@ -1567,19 +1558,18 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr,
struct ipt_target *target;
struct ipt_entry *de;
unsigned int origsize;
int ret, h, j;
int ret, h;
ret = 0;
origsize = *size;
de = (struct ipt_entry *)*dstptr;
memcpy(de, e, sizeof(struct ipt_entry));
j = 0;
*dstptr += sizeof(struct compat_ipt_entry);
ret = IPT_MATCH_ITERATE(e, compat_copy_match_from_user, dstptr, size,
name, &de->ip, de->comefrom, &j);
name, &de->ip, de->comefrom);
if (ret)
goto cleanup_matches;
goto err;
de->target_offset = e->target_offset - (origsize - *size);
t = ipt_get_target(e);
target = t->u.kernel.target;
@ -1613,12 +1603,7 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr,
goto err;
}
ret = 0;
return ret;
err:
module_put(t->u.kernel.target->me);
cleanup_matches:
IPT_MATCH_ITERATE(e, cleanup_match, &j);
return ret;
}
@ -1632,7 +1617,7 @@ translate_compat_table(const char *name,
unsigned int *hook_entries,
unsigned int *underflows)
{
unsigned int i;
unsigned int i, j;
struct xt_table_info *newinfo, *info;
void *pos, *entry0, *entry1;
unsigned int size;
@ -1650,21 +1635,21 @@ translate_compat_table(const char *name,
}
duprintf("translate_compat_table: size %u\n", info->size);
i = 0;
j = 0;
xt_compat_lock(AF_INET);
/* Walk through entries, checking offsets. */
ret = IPT_ENTRY_ITERATE(entry0, total_size,
check_compat_entry_size_and_hooks,
info, &size, entry0,
entry0 + total_size,
hook_entries, underflows, &i, name);
hook_entries, underflows, &j, name);
if (ret != 0)
goto out_unlock;
ret = -EINVAL;
if (i != number) {
if (j != number) {
duprintf("translate_compat_table: %u not %u entries\n",
i, number);
j, number);
goto out_unlock;
}
@ -1723,6 +1708,7 @@ translate_compat_table(const char *name,
free_newinfo:
xt_free_table_info(newinfo);
out:
IPT_ENTRY_ITERATE(entry0, total_size, cleanup_entry, &j);
return ret;
out_unlock:
compat_flush_offsets();