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netfilter: x_tables: Add fixes for CVE-2016-4997, CVE-2016-4998 

...and probably other issues never assigned an ID.
This commit is contained in:
Ben Hutchings 2016-06-24 23:29:28 +02:00
parent f5f99415a2
commit 9fd7bbdf1a
18 changed files with 3046 additions and 0 deletions
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18
debian/changelog vendored
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@ -9,6 +9,24 @@ linux (4.6.2-2) UNRELEASED; urgency=medium
destruction (CVE-2016-4794)
* percpu: fix synchronization between synchronous map extension and
chunk destruction (CVE-2016-4794)
* netfilter: x_tables: Fix parsing of IPT_SO_SET_REPLACE blobs
(CVE-2016-4997, CVE-2016-4998)
- don't move to non-existent next rule
- validate targets of jumps
- add and use xt_check_entry_offsets
- kill check_entry helper
- assert minimum target size
- add compat version of xt_check_entry_offsets
- check standard target size too
- check for bogus target offset
- validate all offsets and sizes in a rule
- don't reject valid target size on some
- arp_tables: simplify translate_compat_table args
- ip_tables: simplify translate_compat_table args
- ip6_tables: simplify translate_compat_table args
- xt_compat_match_from_user doesn't need a retval
- do compat validation via translate_table
- introduce and use xt_copy_counters_from_user
-- Ben Hutchings <ben@decadent.org.uk> Thu, 16 Jun 2016 12:37:27 +0100

210
debian/patches/bugfix/all/netfilter-arp_tables-simplify-translate_compat_table.patch vendored Normal file
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@ -0,0 +1,210 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:32 +0200
Subject: netfilter: arp_tables: simplify translate_compat_table args
Origin: https://git.kernel.org/linus/8dddd32756f6fe8e4e82a63361119b7e2384e02f
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv4/netfilter/arp_tables.c | 82 ++++++++++++++++++-----------------------
1 file changed, 36 insertions(+), 46 deletions(-)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -1214,6 +1214,18 @@ static int do_add_counters(struct net *n
}
#ifdef CONFIG_COMPAT
+struct compat_arpt_replace {
+ char name[XT_TABLE_MAXNAMELEN];
+ u32 valid_hooks;
+ u32 num_entries;
+ u32 size;
+ u32 hook_entry[NF_ARP_NUMHOOKS];
+ u32 underflow[NF_ARP_NUMHOOKS];
+ u32 num_counters;
+ compat_uptr_t counters;
+ struct compat_arpt_entry entries[0];
+};
+
static inline void compat_release_entry(struct compat_arpt_entry *e)
{
struct xt_entry_target *t;
@@ -1229,8 +1241,7 @@ check_compat_entry_size_and_hooks(struct
const unsigned char *base,
const unsigned char *limit,
const unsigned int *hook_entries,
- const unsigned int *underflows,
- const char *name)
+ const unsigned int *underflows)
{
struct xt_entry_target *t;
struct xt_target *target;
@@ -1301,7 +1312,7 @@ out:
static int
compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
- unsigned int *size, const char *name,
+ unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
{
struct xt_entry_target *t;
@@ -1334,14 +1345,9 @@ compat_copy_entry_from_user(struct compa
return ret;
}
-static int translate_compat_table(const char *name,
- unsigned int valid_hooks,
- struct xt_table_info **pinfo,
+static int translate_compat_table(struct xt_table_info **pinfo,
void **pentry0,
- unsigned int total_size,
- unsigned int number,
- unsigned int *hook_entries,
- unsigned int *underflows)
+ const struct compat_arpt_replace *compatr)
{
unsigned int i, j;
struct xt_table_info *newinfo, *info;
@@ -1353,8 +1359,8 @@ static int translate_compat_table(const
info = *pinfo;
entry0 = *pentry0;
- size = total_size;
- info->number = number;
+ size = compatr->size;
+ info->number = compatr->num_entries;
/* Init all hooks to impossible value. */
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
@@ -1365,40 +1371,39 @@ static int translate_compat_table(const
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(NFPROTO_ARP);
- xt_compat_init_offsets(NFPROTO_ARP, number);
+ xt_compat_init_offsets(NFPROTO_ARP, compatr->num_entries);
/* Walk through entries, checking offsets. */
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + total_size,
- hook_entries,
- underflows,
- name);
+ entry0 + compatr->size,
+ compatr->hook_entry,
+ compatr->underflow);
if (ret != 0)
goto out_unlock;
++j;
}
ret = -EINVAL;
- if (j != number) {
+ if (j != compatr->num_entries) {
duprintf("translate_compat_table: %u not %u entries\n",
- j, number);
+ j, compatr->num_entries);
goto out_unlock;
}
/* Check hooks all assigned */
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
/* Only hooks which are valid */
- if (!(valid_hooks & (1 << i)))
+ if (!(compatr->valid_hooks & (1 << i)))
continue;
if (info->hook_entry[i] == 0xFFFFFFFF) {
duprintf("Invalid hook entry %u %u\n",
- i, hook_entries[i]);
+ i, info->hook_entry[i]);
goto out_unlock;
}
if (info->underflow[i] == 0xFFFFFFFF) {
duprintf("Invalid underflow %u %u\n",
- i, underflows[i]);
+ i, info->underflow[i]);
goto out_unlock;
}
}
@@ -1408,17 +1413,17 @@ static int translate_compat_table(const
if (!newinfo)
goto out_unlock;
- newinfo->number = number;
+ newinfo->number = compatr->num_entries;
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
newinfo->hook_entry[i] = info->hook_entry[i];
newinfo->underflow[i] = info->underflow[i];
}
entry1 = newinfo->entries;
pos = entry1;
- size = total_size;
- xt_entry_foreach(iter0, entry0, total_size) {
+ size = compatr->size;
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = compat_copy_entry_from_user(iter0, &pos, &size,
- name, newinfo, entry1);
+ newinfo, entry1);
if (ret != 0)
break;
}
@@ -1428,7 +1433,7 @@ static int translate_compat_table(const
goto free_newinfo;
ret = -ELOOP;
- if (!mark_source_chains(newinfo, valid_hooks, entry1))
+ if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
goto free_newinfo;
i = 0;
@@ -1439,7 +1444,7 @@ static int translate_compat_table(const
break;
}
- ret = check_target(iter1, name);
+ ret = check_target(iter1, compatr->name);
if (ret != 0) {
xt_percpu_counter_free(iter1->counters.pcnt);
break;
@@ -1481,7 +1486,7 @@ static int translate_compat_table(const
free_newinfo:
xt_free_table_info(newinfo);
out:
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
@@ -1493,18 +1498,6 @@ out_unlock:
goto out;
}
-struct compat_arpt_replace {
- char name[XT_TABLE_MAXNAMELEN];
- u32 valid_hooks;
- u32 num_entries;
- u32 size;
- u32 hook_entry[NF_ARP_NUMHOOKS];
- u32 underflow[NF_ARP_NUMHOOKS];
- u32 num_counters;
- compat_uptr_t counters;
- struct compat_arpt_entry entries[0];
-};
-
static int compat_do_replace(struct net *net, void __user *user,
unsigned int len)
{
@@ -1537,10 +1530,7 @@ static int compat_do_replace(struct net
goto free_newinfo;
}
- ret = translate_compat_table(tmp.name, tmp.valid_hooks,
- &newinfo, &loc_cpu_entry, tmp.size,
- tmp.num_entries, tmp.hook_entry,
- tmp.underflow);
+ ret = translate_compat_table(&newinfo, &loc_cpu_entry, &tmp);
if (ret != 0)
goto free_newinfo;

185
debian/patches/bugfix/all/netfilter-ip6_tables-simplify-translate_compat_table.patch vendored Normal file
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@ -0,0 +1,185 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:31 +0200
Subject: netfilter: ip6_tables: simplify translate_compat_table args
Origin: https://git.kernel.org/linus/329a0807124f12fe1c8032f95d8a8eb47047fb0e
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv6/netfilter/ip6_tables.c | 59 +++++++++++++++++------------------------
1 file changed, 24 insertions(+), 35 deletions(-)
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1461,7 +1461,6 @@ compat_copy_entry_to_user(struct ip6t_en
static int
compat_find_calc_match(struct xt_entry_match *m,
- const char *name,
const struct ip6t_ip6 *ipv6,
int *size)
{
@@ -1498,8 +1497,7 @@ check_compat_entry_size_and_hooks(struct
const unsigned char *base,
const unsigned char *limit,
const unsigned int *hook_entries,
- const unsigned int *underflows,
- const char *name)
+ const unsigned int *underflows)
{
struct xt_entry_match *ematch;
struct xt_entry_target *t;
@@ -1535,7 +1533,7 @@ check_compat_entry_size_and_hooks(struct
entry_offset = (void *)e - (void *)base;
j = 0;
xt_ematch_foreach(ematch, e) {
- ret = compat_find_calc_match(ematch, name, &e->ipv6, &off);
+ ret = compat_find_calc_match(ematch, &e->ipv6, &off);
if (ret != 0)
goto release_matches;
++j;
@@ -1584,7 +1582,7 @@ release_matches:
static int
compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
- unsigned int *size, const char *name,
+ unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
{
struct xt_entry_target *t;
@@ -1664,14 +1662,9 @@ static int compat_check_entry(struct ip6
static int
translate_compat_table(struct net *net,
- const char *name,
- unsigned int valid_hooks,
struct xt_table_info **pinfo,
void **pentry0,
- unsigned int total_size,
- unsigned int number,
- unsigned int *hook_entries,
- unsigned int *underflows)
+ const struct compat_ip6t_replace *compatr)
{
unsigned int i, j;
struct xt_table_info *newinfo, *info;
@@ -1683,8 +1676,8 @@ translate_compat_table(struct net *net,
info = *pinfo;
entry0 = *pentry0;
- size = total_size;
- info->number = number;
+ size = compatr->size;
+ info->number = compatr->num_entries;
/* Init all hooks to impossible value. */
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
@@ -1695,40 +1688,39 @@ translate_compat_table(struct net *net,
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(AF_INET6);
- xt_compat_init_offsets(AF_INET6, number);
+ xt_compat_init_offsets(AF_INET6, compatr->num_entries);
/* Walk through entries, checking offsets. */
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + total_size,
- hook_entries,
- underflows,
- name);
+ entry0 + compatr->size,
+ compatr->hook_entry,
+ compatr->underflow);
if (ret != 0)
goto out_unlock;
++j;
}
ret = -EINVAL;
- if (j != number) {
+ if (j != compatr->num_entries) {
duprintf("translate_compat_table: %u not %u entries\n",
- j, number);
+ j, compatr->num_entries);
goto out_unlock;
}
/* Check hooks all assigned */
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
/* Only hooks which are valid */
- if (!(valid_hooks & (1 << i)))
+ if (!(compatr->valid_hooks & (1 << i)))
continue;
if (info->hook_entry[i] == 0xFFFFFFFF) {
duprintf("Invalid hook entry %u %u\n",
- i, hook_entries[i]);
+ i, info->hook_entry[i]);
goto out_unlock;
}
if (info->underflow[i] == 0xFFFFFFFF) {
duprintf("Invalid underflow %u %u\n",
- i, underflows[i]);
+ i, info->underflow[i]);
goto out_unlock;
}
}
@@ -1738,17 +1730,17 @@ translate_compat_table(struct net *net,
if (!newinfo)
goto out_unlock;
- newinfo->number = number;
+ newinfo->number = compatr->num_entries;
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
newinfo->hook_entry[i] = info->hook_entry[i];
newinfo->underflow[i] = info->underflow[i];
}
entry1 = newinfo->entries;
pos = entry1;
- size = total_size;
- xt_entry_foreach(iter0, entry0, total_size) {
+ size = compatr->size;
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = compat_copy_entry_from_user(iter0, &pos, &size,
- name, newinfo, entry1);
+ newinfo, entry1);
if (ret != 0)
break;
}
@@ -1758,12 +1750,12 @@ translate_compat_table(struct net *net,
goto free_newinfo;
ret = -ELOOP;
- if (!mark_source_chains(newinfo, valid_hooks, entry1))
+ if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
goto free_newinfo;
i = 0;
xt_entry_foreach(iter1, entry1, newinfo->size) {
- ret = compat_check_entry(iter1, net, name);
+ ret = compat_check_entry(iter1, net, compatr->name);
if (ret != 0)
break;
++i;
@@ -1803,7 +1795,7 @@ translate_compat_table(struct net *net,
free_newinfo:
xt_free_table_info(newinfo);
out:
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
@@ -1848,10 +1840,7 @@ compat_do_replace(struct net *net, void
goto free_newinfo;
}
- ret = translate_compat_table(net, tmp.name, tmp.valid_hooks,
- &newinfo, &loc_cpu_entry, tmp.size,
- tmp.num_entries, tmp.hook_entry,
- tmp.underflow);
+ ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
if (ret != 0)
goto free_newinfo;

185
debian/patches/bugfix/all/netfilter-ip_tables-simplify-translate_compat_table-.patch vendored Normal file
View File

@ -0,0 +1,185 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:30 +0200
Subject: netfilter: ip_tables: simplify translate_compat_table args
Origin: https://git.kernel.org/linus/7d3f843eed29222254c9feab481f55175a1afcc9
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv4/netfilter/ip_tables.c | 59 +++++++++++++++++-------------------------
1 file changed, 24 insertions(+), 35 deletions(-)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1449,7 +1449,6 @@ compat_copy_entry_to_user(struct ipt_ent
static int
compat_find_calc_match(struct xt_entry_match *m,
- const char *name,
const struct ipt_ip *ip,
int *size)
{
@@ -1486,8 +1485,7 @@ check_compat_entry_size_and_hooks(struct
const unsigned char *base,
const unsigned char *limit,
const unsigned int *hook_entries,
- const unsigned int *underflows,
- const char *name)
+ const unsigned int *underflows)
{
struct xt_entry_match *ematch;
struct xt_entry_target *t;
@@ -1523,7 +1521,7 @@ check_compat_entry_size_and_hooks(struct
entry_offset = (void *)e - (void *)base;
j = 0;
xt_ematch_foreach(ematch, e) {
- ret = compat_find_calc_match(ematch, name, &e->ip, &off);
+ ret = compat_find_calc_match(ematch, &e->ip, &off);
if (ret != 0)
goto release_matches;
++j;
@@ -1572,7 +1570,7 @@ release_matches:
static int
compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
- unsigned int *size, const char *name,
+ unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
{
struct xt_entry_target *t;
@@ -1655,14 +1653,9 @@ compat_check_entry(struct ipt_entry *e,
static int
translate_compat_table(struct net *net,
- const char *name,
- unsigned int valid_hooks,
struct xt_table_info **pinfo,
void **pentry0,
- unsigned int total_size,
- unsigned int number,
- unsigned int *hook_entries,
- unsigned int *underflows)
+ const struct compat_ipt_replace *compatr)
{
unsigned int i, j;
struct xt_table_info *newinfo, *info;
@@ -1674,8 +1667,8 @@ translate_compat_table(struct net *net,
info = *pinfo;
entry0 = *pentry0;
- size = total_size;
- info->number = number;
+ size = compatr->size;
+ info->number = compatr->num_entries;
/* Init all hooks to impossible value. */
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
@@ -1686,40 +1679,39 @@ translate_compat_table(struct net *net,
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(AF_INET);
- xt_compat_init_offsets(AF_INET, number);
+ xt_compat_init_offsets(AF_INET, compatr->num_entries);
/* Walk through entries, checking offsets. */
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + total_size,
- hook_entries,
- underflows,
- name);
+ entry0 + compatr->size,
+ compatr->hook_entry,
+ compatr->underflow);
if (ret != 0)
goto out_unlock;
++j;
}
ret = -EINVAL;
- if (j != number) {
+ if (j != compatr->num_entries) {
duprintf("translate_compat_table: %u not %u entries\n",
- j, number);
+ j, compatr->num_entries);
goto out_unlock;
}
/* Check hooks all assigned */
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
/* Only hooks which are valid */
- if (!(valid_hooks & (1 << i)))
+ if (!(compatr->valid_hooks & (1 << i)))
continue;
if (info->hook_entry[i] == 0xFFFFFFFF) {
duprintf("Invalid hook entry %u %u\n",
- i, hook_entries[i]);
+ i, info->hook_entry[i]);
goto out_unlock;
}
if (info->underflow[i] == 0xFFFFFFFF) {
duprintf("Invalid underflow %u %u\n",
- i, underflows[i]);
+ i, info->underflow[i]);
goto out_unlock;
}
}
@@ -1729,17 +1721,17 @@ translate_compat_table(struct net *net,
if (!newinfo)
goto out_unlock;
- newinfo->number = number;
+ newinfo->number = compatr->num_entries;
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
newinfo->hook_entry[i] = info->hook_entry[i];
newinfo->underflow[i] = info->underflow[i];
}
entry1 = newinfo->entries;
pos = entry1;
- size = total_size;
- xt_entry_foreach(iter0, entry0, total_size) {
+ size = compatr->size;
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = compat_copy_entry_from_user(iter0, &pos, &size,
- name, newinfo, entry1);
+ newinfo, entry1);
if (ret != 0)
break;
}
@@ -1749,12 +1741,12 @@ translate_compat_table(struct net *net,
goto free_newinfo;
ret = -ELOOP;
- if (!mark_source_chains(newinfo, valid_hooks, entry1))
+ if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
goto free_newinfo;
i = 0;
xt_entry_foreach(iter1, entry1, newinfo->size) {
- ret = compat_check_entry(iter1, net, name);
+ ret = compat_check_entry(iter1, net, compatr->name);
if (ret != 0)
break;
++i;
@@ -1794,7 +1786,7 @@ translate_compat_table(struct net *net,
free_newinfo:
xt_free_table_info(newinfo);
out:
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
@@ -1839,10 +1831,7 @@ compat_do_replace(struct net *net, void
goto free_newinfo;
}
- ret = translate_compat_table(net, tmp.name, tmp.valid_hooks,
- &newinfo, &loc_cpu_entry, tmp.size,
- tmp.num_entries, tmp.hook_entry,
- tmp.underflow);
+ ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
if (ret != 0)
goto free_newinfo;

151
debian/patches/bugfix/all/netfilter-x_tables-add-and-use-xt_check_entry_offset.patch vendored Normal file
View File

@ -0,0 +1,151 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:23 +0200
Subject: netfilter: x_tables: add and use xt_check_entry_offsets
Origin: https://git.kernel.org/linus/7d35812c3214afa5b37a675113555259cfd67b98
Currently arp/ip and ip6tables each implement a short helper to check that
the target offset is large enough to hold one xt_entry_target struct and
that t->u.target_size fits within the current rule.
Unfortunately these checks are not sufficient.
To avoid adding new tests to all of ip/ip6/arptables move the current
checks into a helper, then extend this helper in followup patches.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
include/linux/netfilter/x_tables.h | 4 ++++
net/ipv4/netfilter/arp_tables.c | 11 +----------
net/ipv4/netfilter/ip_tables.c | 12 +-----------
net/ipv6/netfilter/ip6_tables.c | 12 +-----------
net/netfilter/x_tables.c | 34 ++++++++++++++++++++++++++++++++++
5 files changed, 41 insertions(+), 32 deletions(-)
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -242,6 +242,10 @@ void xt_unregister_match(struct xt_match
int xt_register_matches(struct xt_match *match, unsigned int n);
void xt_unregister_matches(struct xt_match *match, unsigned int n);
+int xt_check_entry_offsets(const void *base,
+ unsigned int target_offset,
+ unsigned int next_offset);
+
int xt_check_match(struct xt_mtchk_param *, unsigned int size, u_int8_t proto,
bool inv_proto);
int xt_check_target(struct xt_tgchk_param *, unsigned int size, u_int8_t proto,
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -496,19 +496,10 @@ next:
static inline int check_entry(const struct arpt_entry *e)
{
- const struct xt_entry_target *t;
-
if (!arp_checkentry(&e->arp))
return -EINVAL;
- if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset)
- return -EINVAL;
-
- t = arpt_get_target_c(e);
- if (e->target_offset + t->u.target_size > e->next_offset)
- return -EINVAL;
-
- return 0;
+ return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
}
static inline int check_target(struct arpt_entry *e, const char *name)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -590,20 +590,10 @@ static void cleanup_match(struct xt_entr
static int
check_entry(const struct ipt_entry *e)
{
- const struct xt_entry_target *t;
-
if (!ip_checkentry(&e->ip))
return -EINVAL;
- if (e->target_offset + sizeof(struct xt_entry_target) >
- e->next_offset)
- return -EINVAL;
-
- t = ipt_get_target_c(e);
- if (e->target_offset + t->u.target_size > e->next_offset)
- return -EINVAL;
-
- return 0;
+ return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
}
static int
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -602,20 +602,10 @@ static void cleanup_match(struct xt_entr
static int
check_entry(const struct ip6t_entry *e)
{
- const struct xt_entry_target *t;
-
if (!ip6_checkentry(&e->ipv6))
return -EINVAL;
- if (e->target_offset + sizeof(struct xt_entry_target) >
- e->next_offset)
- return -EINVAL;
-
- t = ip6t_get_target_c(e);
- if (e->target_offset + t->u.target_size > e->next_offset)
- return -EINVAL;
-
- return 0;
+ return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
}
static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -541,6 +541,40 @@ int xt_compat_match_to_user(const struct
EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
#endif /* CONFIG_COMPAT */
+/**
+ * xt_check_entry_offsets - validate arp/ip/ip6t_entry
+ *
+ * @base: pointer to arp/ip/ip6t_entry
+ * @target_offset: the arp/ip/ip6_t->target_offset
+ * @next_offset: the arp/ip/ip6_t->next_offset
+ *
+ * validates that target_offset and next_offset are sane.
+ *
+ * The arp/ip/ip6t_entry structure @base must have passed following tests:
+ * - it must point to a valid memory location
+ * - base to base + next_offset must be accessible, i.e. not exceed allocated
+ * length.
+ *
+ * Return: 0 on success, negative errno on failure.
+ */
+int xt_check_entry_offsets(const void *base,
+ unsigned int target_offset,
+ unsigned int next_offset)
+{
+ const struct xt_entry_target *t;
+ const char *e = base;
+
+ if (target_offset + sizeof(*t) > next_offset)
+ return -EINVAL;
+
+ t = (void *)(e + target_offset);
+ if (target_offset + t->u.target_size > next_offset)
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL(xt_check_entry_offsets);
+
int xt_check_target(struct xt_tgchk_param *par,
unsigned int size, u_int8_t proto, bool inv_proto)
{

105
debian/patches/bugfix/all/netfilter-x_tables-add-compat-version-of-xt_check_en.patch vendored Normal file
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@ -0,0 +1,105 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:26 +0200
Subject: netfilter: x_tables: add compat version of xt_check_entry_offsets
Origin: https://git.kernel.org/linus/fc1221b3a163d1386d1052184202d5dc50d302d1
32bit rulesets have different layout and alignment requirements, so once
more integrity checks get added to xt_check_entry_offsets it will reject
well-formed 32bit rulesets.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
include/linux/netfilter/x_tables.h | 3 +++
net/ipv4/netfilter/arp_tables.c | 3 ++-
net/ipv4/netfilter/ip_tables.c | 3 ++-
net/ipv6/netfilter/ip6_tables.c | 3 ++-
net/netfilter/x_tables.c | 22 ++++++++++++++++++++++
5 files changed, 31 insertions(+), 3 deletions(-)
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -494,6 +494,9 @@ void xt_compat_target_from_user(struct x
unsigned int *size);
int xt_compat_target_to_user(const struct xt_entry_target *t,
void __user **dstptr, unsigned int *size);
+int xt_compat_check_entry_offsets(const void *base,
+ unsigned int target_offset,
+ unsigned int next_offset);
#endif /* CONFIG_COMPAT */
#endif /* _X_TABLES_H */
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -1254,7 +1254,8 @@ check_compat_entry_size_and_hooks(struct
if (!arp_checkentry(&e->arp))
return -EINVAL;
- ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ ret = xt_compat_check_entry_offsets(e, e->target_offset,
+ e->next_offset);
if (ret)
return ret;
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1513,7 +1513,8 @@ check_compat_entry_size_and_hooks(struct
if (!ip_checkentry(&e->ip))
return -EINVAL;
- ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ ret = xt_compat_check_entry_offsets(e,
+ e->target_offset, e->next_offset);
if (ret)
return ret;
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1525,7 +1525,8 @@ check_compat_entry_size_and_hooks(struct
if (!ip6_checkentry(&e->ipv6))
return -EINVAL;
- ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ ret = xt_compat_check_entry_offsets(e,
+ e->target_offset, e->next_offset);
if (ret)
return ret;
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -539,6 +539,27 @@ int xt_compat_match_to_user(const struct
return 0;
}
EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
+
+int xt_compat_check_entry_offsets(const void *base,
+ unsigned int target_offset,
+ unsigned int next_offset)
+{
+ const struct compat_xt_entry_target *t;
+ const char *e = base;
+
+ if (target_offset + sizeof(*t) > next_offset)
+ return -EINVAL;
+
+ t = (void *)(e + target_offset);
+ if (t->u.target_size < sizeof(*t))
+ return -EINVAL;
+
+ if (target_offset + t->u.target_size > next_offset)
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL(xt_compat_check_entry_offsets);
#endif /* CONFIG_COMPAT */
/**
@@ -549,6 +570,7 @@ EXPORT_SYMBOL_GPL(xt_compat_match_to_use
* @next_offset: the arp/ip/ip6_t->next_offset
*
* validates that target_offset and next_offset are sane.
+ * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version.
*
* The arp/ip/ip6t_entry structure @base must have passed following tests:
* - it must point to a valid memory location

25
debian/patches/bugfix/all/netfilter-x_tables-assert-minimum-target-size.patch vendored Normal file
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@ -0,0 +1,25 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:25 +0200
Subject: netfilter: x_tables: assert minimum target size
Origin: https://git.kernel.org/linus/a08e4e190b866579896c09af59b3bdca821da2cd
The target size includes the size of the xt_entry_target struct.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/x_tables.c | 3 +++
1 file changed, 3 insertions(+)
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -568,6 +568,9 @@ int xt_check_entry_offsets(const void *b
return -EINVAL;
t = (void *)(e + target_offset);
+ if (t->u.target_size < sizeof(*t))
+ return -EINVAL;
+
if (target_offset + t->u.target_size > next_offset)
return -EINVAL;

164
debian/patches/bugfix/all/netfilter-x_tables-check-for-bogus-target-offset.patch vendored Normal file
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@ -0,0 +1,164 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:28 +0200
Subject: netfilter: x_tables: check for bogus target offset
Origin: https://git.kernel.org/linus/ce683e5f9d045e5d67d1312a42b359cb2ab2a13c
We're currently asserting that targetoff + targetsize <= nextoff.
Extend it to also check that targetoff is >= sizeof(xt_entry).
Since this is generic code, add an argument pointing to the start of the
match/target, we can then derive the base structure size from the delta.
We also need the e->elems pointer in a followup change to validate matches.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
include/linux/netfilter/x_tables.h | 4 ++--
net/ipv4/netfilter/arp_tables.c | 5 +++--
net/ipv4/netfilter/ip_tables.c | 5 +++--
net/ipv6/netfilter/ip6_tables.c | 5 +++--
net/netfilter/x_tables.c | 17 +++++++++++++++--
5 files changed, 26 insertions(+), 10 deletions(-)
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -242,7 +242,7 @@ void xt_unregister_match(struct xt_match
int xt_register_matches(struct xt_match *match, unsigned int n);
void xt_unregister_matches(struct xt_match *match, unsigned int n);
-int xt_check_entry_offsets(const void *base,
+int xt_check_entry_offsets(const void *base, const char *elems,
unsigned int target_offset,
unsigned int next_offset);
@@ -494,7 +494,7 @@ void xt_compat_target_from_user(struct x
unsigned int *size);
int xt_compat_target_to_user(const struct xt_entry_target *t,
void __user **dstptr, unsigned int *size);
-int xt_compat_check_entry_offsets(const void *base,
+int xt_compat_check_entry_offsets(const void *base, const char *elems,
unsigned int target_offset,
unsigned int next_offset);
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -592,7 +592,8 @@ static inline int check_entry_size_and_h
if (!arp_checkentry(&e->arp))
return -EINVAL;
- err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ err = xt_check_entry_offsets(e, e->elems, e->target_offset,
+ e->next_offset);
if (err)
return err;
@@ -1254,7 +1255,7 @@ check_compat_entry_size_and_hooks(struct
if (!arp_checkentry(&e->arp))
return -EINVAL;
- ret = xt_compat_check_entry_offsets(e, e->target_offset,
+ ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset,
e->next_offset);
if (ret)
return ret;
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -754,7 +754,8 @@ check_entry_size_and_hooks(struct ipt_en
if (!ip_checkentry(&e->ip))
return -EINVAL;
- err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ err = xt_check_entry_offsets(e, e->elems, e->target_offset,
+ e->next_offset);
if (err)
return err;
@@ -1513,7 +1514,7 @@ check_compat_entry_size_and_hooks(struct
if (!ip_checkentry(&e->ip))
return -EINVAL;
- ret = xt_compat_check_entry_offsets(e,
+ ret = xt_compat_check_entry_offsets(e, e->elems,
e->target_offset, e->next_offset);
if (ret)
return ret;
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -766,7 +766,8 @@ check_entry_size_and_hooks(struct ip6t_e
if (!ip6_checkentry(&e->ipv6))
return -EINVAL;
- err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ err = xt_check_entry_offsets(e, e->elems, e->target_offset,
+ e->next_offset);
if (err)
return err;
@@ -1525,7 +1526,7 @@ check_compat_entry_size_and_hooks(struct
if (!ip6_checkentry(&e->ipv6))
return -EINVAL;
- ret = xt_compat_check_entry_offsets(e,
+ ret = xt_compat_check_entry_offsets(e, e->elems,
e->target_offset, e->next_offset);
if (ret)
return ret;
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -546,14 +546,17 @@ struct compat_xt_standard_target {
compat_uint_t verdict;
};
-/* see xt_check_entry_offsets */
-int xt_compat_check_entry_offsets(const void *base,
+int xt_compat_check_entry_offsets(const void *base, const char *elems,
unsigned int target_offset,
unsigned int next_offset)
{
+ long size_of_base_struct = elems - (const char *)base;
const struct compat_xt_entry_target *t;
const char *e = base;
+ if (target_offset < size_of_base_struct)
+ return -EINVAL;
+
if (target_offset + sizeof(*t) > next_offset)
return -EINVAL;
@@ -577,12 +580,16 @@ EXPORT_SYMBOL(xt_compat_check_entry_offs
* xt_check_entry_offsets - validate arp/ip/ip6t_entry
*
* @base: pointer to arp/ip/ip6t_entry
+ * @elems: pointer to first xt_entry_match, i.e. ip(6)t_entry->elems
* @target_offset: the arp/ip/ip6_t->target_offset
* @next_offset: the arp/ip/ip6_t->next_offset
*
* validates that target_offset and next_offset are sane.
* Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version.
*
+ * This function does not validate the targets or matches themselves, it
+ * only tests that all the offsets and sizes are correct.
+ *
* The arp/ip/ip6t_entry structure @base must have passed following tests:
* - it must point to a valid memory location
* - base to base + next_offset must be accessible, i.e. not exceed allocated
@@ -591,12 +598,18 @@ EXPORT_SYMBOL(xt_compat_check_entry_offs
* Return: 0 on success, negative errno on failure.
*/
int xt_check_entry_offsets(const void *base,
+ const char *elems,
unsigned int target_offset,
unsigned int next_offset)
{
+ long size_of_base_struct = elems - (const char *)base;
const struct xt_entry_target *t;
const char *e = base;
+ /* target start is within the ip/ip6/arpt_entry struct */
+ if (target_offset < size_of_base_struct)
+ return -EINVAL;
+
if (target_offset + sizeof(*t) > next_offset)
return -EINVAL;

60
debian/patches/bugfix/all/netfilter-x_tables-check-standard-target-size-too.patch vendored Normal file
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@ -0,0 +1,60 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:27 +0200
Subject: netfilter: x_tables: check standard target size too
Origin: https://git.kernel.org/linus/7ed2abddd20cf8f6bd27f65bd218f26fa5bf7f44
We have targets and standard targets -- the latter carries a verdict.
The ip/ip6tables validation functions will access t->verdict for the
standard targets to fetch the jump offset or verdict for chainloop
detection, but this happens before the targets get checked/validated.
Thus we also need to check for verdict presence here, else t->verdict
can point right after a blob.
Spotted with UBSAN while testing malformed blobs.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/x_tables.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -540,6 +540,13 @@ int xt_compat_match_to_user(const struct
}
EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
+/* non-compat version may have padding after verdict */
+struct compat_xt_standard_target {
+ struct compat_xt_entry_target t;
+ compat_uint_t verdict;
+};
+
+/* see xt_check_entry_offsets */
int xt_compat_check_entry_offsets(const void *base,
unsigned int target_offset,
unsigned int next_offset)
@@ -557,6 +564,10 @@ int xt_compat_check_entry_offsets(const
if (target_offset + t->u.target_size > next_offset)
return -EINVAL;
+ if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
+ target_offset + sizeof(struct compat_xt_standard_target) != next_offset)
+ return -EINVAL;
+
return 0;
}
EXPORT_SYMBOL(xt_compat_check_entry_offsets);
@@ -596,6 +607,10 @@ int xt_check_entry_offsets(const void *b
if (target_offset + t->u.target_size > next_offset)
return -EINVAL;
+ if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
+ target_offset + sizeof(struct xt_standard_target) != next_offset)
+ return -EINVAL;
+
return 0;
}
EXPORT_SYMBOL(xt_check_entry_offsets);

798
debian/patches/bugfix/all/netfilter-x_tables-do-compat-validation-via-translat.patch vendored Normal file
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@ -0,0 +1,798 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:34 +0200
Subject: netfilter: x_tables: do compat validation via translate_table
Origin: https://git.kernel.org/linus/09d9686047dbbe1cf4faa558d3ecc4aae2046054
This looks like refactoring, but its also a bug fix.
Problem is that the compat path (32bit iptables, 64bit kernel) lacks a few
sanity tests that are done in the normal path.
For example, we do not check for underflows and the base chain policies.
While its possible to also add such checks to the compat path, its more
copy&pastry, for instance we cannot reuse check_underflow() helper as
e->target_offset differs in the compat case.
Other problem is that it makes auditing for validation errors harder; two
places need to be checked and kept in sync.
At a high level 32 bit compat works like this:
1- initial pass over blob:
validate match/entry offsets, bounds checking
lookup all matches and targets
do bookkeeping wrt. size delta of 32/64bit structures
assign match/target.u.kernel pointer (points at kernel
implementation, needed to access ->compatsize etc.)
2- allocate memory according to the total bookkeeping size to
contain the translated ruleset
3- second pass over original blob:
for each entry, copy the 32bit representation to the newly allocated
memory. This also does any special match translations (e.g.
adjust 32bit to 64bit longs, etc).
4- check if ruleset is free of loops (chase all jumps)
5-first pass over translated blob:
call the checkentry function of all matches and targets.
The alternative implemented by this patch is to drop steps 3&4 from the
compat process, the translation is changed into an intermediate step
rather than a full 1:1 translate_table replacement.
In the 2nd pass (step #3), change the 64bit ruleset back to a kernel
representation, i.e. put() the kernel pointer and restore ->u.user.name .
This gets us a 64bit ruleset that is in the format generated by a 64bit
iptables userspace -- we can then use translate_table() to get the
'native' sanity checks.
This has two drawbacks:
1. we re-validate all the match and target entry structure sizes even
though compat translation is supposed to never generate bogus offsets.
2. we put and then re-lookup each match and target.
THe upside is that we get all sanity tests and ruleset validations
provided by the normal path and can remove some duplicated compat code.
iptables-restore time of autogenerated ruleset with 300k chains of form
-A CHAIN0001 -m limit --limit 1/s -j CHAIN0002
-A CHAIN0002 -m limit --limit 1/s -j CHAIN0003
shows no noticeable differences in restore times:
old: 0m30.796s
new: 0m31.521s
64bit: 0m25.674s
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv4/netfilter/arp_tables.c | 114 ++++++-----------------------
net/ipv4/netfilter/ip_tables.c | 155 ++++++++--------------------------------
net/ipv6/netfilter/ip6_tables.c | 148 ++++++--------------------------------
net/netfilter/x_tables.c | 8 +++
4 files changed, 83 insertions(+), 342 deletions(-)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -1234,19 +1234,17 @@ static inline void compat_release_entry(
module_put(t->u.kernel.target->me);
}
-static inline int
+static int
check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
const unsigned char *base,
- const unsigned char *limit,
- const unsigned int *hook_entries,
- const unsigned int *underflows)
+ const unsigned char *limit)
{
struct xt_entry_target *t;
struct xt_target *target;
unsigned int entry_offset;
- int ret, off, h;
+ int ret, off;
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
@@ -1291,17 +1289,6 @@ check_compat_entry_size_and_hooks(struct
if (ret)
goto release_target;
- /* Check hooks & underflows */
- for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
- if ((unsigned char *)e - base == hook_entries[h])
- newinfo->hook_entry[h] = hook_entries[h];
- if ((unsigned char *)e - base == underflows[h])
- newinfo->underflow[h] = underflows[h];
- }
-
- /* Clear counters and comefrom */
- memset(&e->counters, 0, sizeof(e->counters));
- e->comefrom = 0;
return 0;
release_target:
@@ -1351,7 +1338,7 @@ static int translate_compat_table(struct
struct xt_table_info *newinfo, *info;
void *pos, *entry0, *entry1;
struct compat_arpt_entry *iter0;
- struct arpt_entry *iter1;
+ struct arpt_replace repl;
unsigned int size;
int ret = 0;
@@ -1360,12 +1347,6 @@ static int translate_compat_table(struct
size = compatr->size;
info->number = compatr->num_entries;
- /* Init all hooks to impossible value. */
- for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
- info->hook_entry[i] = 0xFFFFFFFF;
- info->underflow[i] = 0xFFFFFFFF;
- }
-
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(NFPROTO_ARP);
@@ -1374,9 +1355,7 @@ static int translate_compat_table(struct
xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + compatr->size,
- compatr->hook_entry,
- compatr->underflow);
+ entry0 + compatr->size);
if (ret != 0)
goto out_unlock;
++j;
@@ -1389,23 +1368,6 @@ static int translate_compat_table(struct
goto out_unlock;
}
- /* Check hooks all assigned */
- for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
- /* Only hooks which are valid */
- if (!(compatr->valid_hooks & (1 << i)))
- continue;
- if (info->hook_entry[i] == 0xFFFFFFFF) {
- duprintf("Invalid hook entry %u %u\n",
- i, info->hook_entry[i]);
- goto out_unlock;
- }
- if (info->underflow[i] == 0xFFFFFFFF) {
- duprintf("Invalid underflow %u %u\n",
- i, info->underflow[i]);
- goto out_unlock;
- }
- }
-
ret = -ENOMEM;
newinfo = xt_alloc_table_info(size);
if (!newinfo)
@@ -1422,55 +1384,26 @@ static int translate_compat_table(struct
xt_entry_foreach(iter0, entry0, compatr->size)
compat_copy_entry_from_user(iter0, &pos, &size,
newinfo, entry1);
+
+ /* all module references in entry0 are now gone */
+
xt_compat_flush_offsets(NFPROTO_ARP);
xt_compat_unlock(NFPROTO_ARP);
- ret = -ELOOP;
- if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
- goto free_newinfo;
-
- i = 0;
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- iter1->counters.pcnt = xt_percpu_counter_alloc();
- if (IS_ERR_VALUE(iter1->counters.pcnt)) {
- ret = -ENOMEM;
- break;
- }
+ memcpy(&repl, compatr, sizeof(*compatr));
- ret = check_target(iter1, compatr->name);
- if (ret != 0) {
- xt_percpu_counter_free(iter1->counters.pcnt);
- break;
- }
- ++i;
- if (strcmp(arpt_get_target(iter1)->u.user.name,
- XT_ERROR_TARGET) == 0)
- ++newinfo->stacksize;
- }
- if (ret) {
- /*
- * The first i matches need cleanup_entry (calls ->destroy)
- * because they had called ->check already. The other j-i
- * entries need only release.
- */
- int skip = i;
- j -= i;
- xt_entry_foreach(iter0, entry0, newinfo->size) {
- if (skip-- > 0)
- continue;
- if (j-- == 0)
- break;
- compat_release_entry(iter0);
- }
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- if (i-- == 0)
- break;
- cleanup_entry(iter1);
- }
- xt_free_table_info(newinfo);
- return ret;
+ for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
+ repl.hook_entry[i] = newinfo->hook_entry[i];
+ repl.underflow[i] = newinfo->underflow[i];
}
+ repl.num_counters = 0;
+ repl.counters = NULL;
+ repl.size = newinfo->size;
+ ret = translate_table(newinfo, entry1, &repl);
+ if (ret)
+ goto free_newinfo;
+
*pinfo = newinfo;
*pentry0 = entry1;
xt_free_table_info(info);
@@ -1478,17 +1411,16 @@ static int translate_compat_table(struct
free_newinfo:
xt_free_table_info(newinfo);
-out:
+ return ret;
+out_unlock:
+ xt_compat_flush_offsets(NFPROTO_ARP);
+ xt_compat_unlock(NFPROTO_ARP);
xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
}
return ret;
-out_unlock:
- xt_compat_flush_offsets(NFPROTO_ARP);
- xt_compat_unlock(NFPROTO_ARP);
- goto out;
}
static int compat_do_replace(struct net *net, void __user *user,
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1483,16 +1483,14 @@ check_compat_entry_size_and_hooks(struct
struct xt_table_info *newinfo,
unsigned int *size,
const unsigned char *base,
- const unsigned char *limit,
- const unsigned int *hook_entries,
- const unsigned int *underflows)
+ const unsigned char *limit)
{
struct xt_entry_match *ematch;
struct xt_entry_target *t;
struct xt_target *target;
unsigned int entry_offset;
unsigned int j;
- int ret, off, h;
+ int ret, off;
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 ||
@@ -1544,17 +1542,6 @@ check_compat_entry_size_and_hooks(struct
if (ret)
goto out;
- /* Check hooks & underflows */
- for (h = 0; h < NF_INET_NUMHOOKS; h++) {
- if ((unsigned char *)e - base == hook_entries[h])
- newinfo->hook_entry[h] = hook_entries[h];
- if ((unsigned char *)e - base == underflows[h])
- newinfo->underflow[h] = underflows[h];
- }
-
- /* Clear counters and comefrom */
- memset(&e->counters, 0, sizeof(e->counters));
- e->comefrom = 0;
return 0;
out:
@@ -1597,6 +1584,7 @@ compat_copy_entry_from_user(struct compa
xt_compat_target_from_user(t, dstptr, size);
de->next_offset = e->next_offset - (origsize - *size);
+
for (h = 0; h < NF_INET_NUMHOOKS; h++) {
if ((unsigned char *)de - base < newinfo->hook_entry[h])
newinfo->hook_entry[h] -= origsize - *size;
@@ -1606,48 +1594,6 @@ compat_copy_entry_from_user(struct compa
}
static int
-compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)
-{
- struct xt_entry_match *ematch;
- struct xt_mtchk_param mtpar;
- unsigned int j;
- int ret = 0;
-
- e->counters.pcnt = xt_percpu_counter_alloc();
- if (IS_ERR_VALUE(e->counters.pcnt))
- return -ENOMEM;
-
- j = 0;
- mtpar.net = net;
- mtpar.table = name;
- mtpar.entryinfo = &e->ip;
- mtpar.hook_mask = e->comefrom;
- mtpar.family = NFPROTO_IPV4;
- xt_ematch_foreach(ematch, e) {
- ret = check_match(ematch, &mtpar);
- if (ret != 0)
- goto cleanup_matches;
- ++j;
- }
-
- ret = check_target(e, net, name);
- if (ret)
- goto cleanup_matches;
- return 0;
-
- cleanup_matches:
- xt_ematch_foreach(ematch, e) {
- if (j-- == 0)
- break;
- cleanup_match(ematch, net);
- }
-
- xt_percpu_counter_free(e->counters.pcnt);
-
- return ret;
-}
-
-static int
translate_compat_table(struct net *net,
struct xt_table_info **pinfo,
void **pentry0,
@@ -1657,7 +1603,7 @@ translate_compat_table(struct net *net,
struct xt_table_info *newinfo, *info;
void *pos, *entry0, *entry1;
struct compat_ipt_entry *iter0;
- struct ipt_entry *iter1;
+ struct ipt_replace repl;
unsigned int size;
int ret;
@@ -1666,12 +1612,6 @@ translate_compat_table(struct net *net,
size = compatr->size;
info->number = compatr->num_entries;
- /* Init all hooks to impossible value. */
- for (i = 0; i < NF_INET_NUMHOOKS; i++) {
- info->hook_entry[i] = 0xFFFFFFFF;
- info->underflow[i] = 0xFFFFFFFF;
- }
-
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(AF_INET);
@@ -1680,9 +1620,7 @@ translate_compat_table(struct net *net,
xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + compatr->size,
- compatr->hook_entry,
- compatr->underflow);
+ entry0 + compatr->size);
if (ret != 0)
goto out_unlock;
++j;
@@ -1695,23 +1633,6 @@ translate_compat_table(struct net *net,
goto out_unlock;
}
- /* Check hooks all assigned */
- for (i = 0; i < NF_INET_NUMHOOKS; i++) {
- /* Only hooks which are valid */
- if (!(compatr->valid_hooks & (1 << i)))
- continue;
- if (info->hook_entry[i] == 0xFFFFFFFF) {
- duprintf("Invalid hook entry %u %u\n",
- i, info->hook_entry[i]);
- goto out_unlock;
- }
- if (info->underflow[i] == 0xFFFFFFFF) {
- duprintf("Invalid underflow %u %u\n",
- i, info->underflow[i]);
- goto out_unlock;
- }
- }
-
ret = -ENOMEM;
newinfo = xt_alloc_table_info(size);
if (!newinfo)
@@ -1719,8 +1640,8 @@ translate_compat_table(struct net *net,
newinfo->number = compatr->num_entries;
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
- newinfo->hook_entry[i] = info->hook_entry[i];
- newinfo->underflow[i] = info->underflow[i];
+ newinfo->hook_entry[i] = compatr->hook_entry[i];
+ newinfo->underflow[i] = compatr->underflow[i];
}
entry1 = newinfo->entries;
pos = entry1;
@@ -1729,47 +1650,30 @@ translate_compat_table(struct net *net,
compat_copy_entry_from_user(iter0, &pos, &size,
newinfo, entry1);
+ /* all module references in entry0 are now gone.
+ * entry1/newinfo contains a 64bit ruleset that looks exactly as
+ * generated by 64bit userspace.
+ *
+ * Call standard translate_table() to validate all hook_entrys,
+ * underflows, check for loops, etc.
+ */
xt_compat_flush_offsets(AF_INET);
xt_compat_unlock(AF_INET);
- ret = -ELOOP;
- if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
- goto free_newinfo;
+ memcpy(&repl, compatr, sizeof(*compatr));
- i = 0;
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- ret = compat_check_entry(iter1, net, compatr->name);
- if (ret != 0)
- break;
- ++i;
- if (strcmp(ipt_get_target(iter1)->u.user.name,
- XT_ERROR_TARGET) == 0)
- ++newinfo->stacksize;
- }
- if (ret) {
- /*
- * The first i matches need cleanup_entry (calls ->destroy)
- * because they had called ->check already. The other j-i
- * entries need only release.
- */
- int skip = i;
- j -= i;
- xt_entry_foreach(iter0, entry0, newinfo->size) {
- if (skip-- > 0)
- continue;
- if (j-- == 0)
- break;
- compat_release_entry(iter0);
- }
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- if (i-- == 0)
- break;
- cleanup_entry(iter1, net);
- }
- xt_free_table_info(newinfo);
- return ret;
+ for (i = 0; i < NF_INET_NUMHOOKS; i++) {
+ repl.hook_entry[i] = newinfo->hook_entry[i];
+ repl.underflow[i] = newinfo->underflow[i];
}
+ repl.num_counters = 0;
+ repl.counters = NULL;
+ repl.size = newinfo->size;
+ ret = translate_table(net, newinfo, entry1, &repl);
+ if (ret)
+ goto free_newinfo;
+
*pinfo = newinfo;
*pentry0 = entry1;
xt_free_table_info(info);
@@ -1777,17 +1681,16 @@ translate_compat_table(struct net *net,
free_newinfo:
xt_free_table_info(newinfo);
-out:
+ return ret;
+out_unlock:
+ xt_compat_flush_offsets(AF_INET);
+ xt_compat_unlock(AF_INET);
xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
}
return ret;
-out_unlock:
- xt_compat_flush_offsets(AF_INET);
- xt_compat_unlock(AF_INET);
- goto out;
}
static int
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1495,16 +1495,14 @@ check_compat_entry_size_and_hooks(struct
struct xt_table_info *newinfo,
unsigned int *size,
const unsigned char *base,
- const unsigned char *limit,
- const unsigned int *hook_entries,
- const unsigned int *underflows)
+ const unsigned char *limit)
{
struct xt_entry_match *ematch;
struct xt_entry_target *t;
struct xt_target *target;
unsigned int entry_offset;
unsigned int j;
- int ret, off, h;
+ int ret, off;
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 ||
@@ -1556,17 +1554,6 @@ check_compat_entry_size_and_hooks(struct
if (ret)
goto out;
- /* Check hooks & underflows */
- for (h = 0; h < NF_INET_NUMHOOKS; h++) {
- if ((unsigned char *)e - base == hook_entries[h])
- newinfo->hook_entry[h] = hook_entries[h];
- if ((unsigned char *)e - base == underflows[h])
- newinfo->underflow[h] = underflows[h];
- }
-
- /* Clear counters and comefrom */
- memset(&e->counters, 0, sizeof(e->counters));
- e->comefrom = 0;
return 0;
out:
@@ -1615,47 +1602,6 @@ compat_copy_entry_from_user(struct compa
}
}
-static int compat_check_entry(struct ip6t_entry *e, struct net *net,
- const char *name)
-{
- unsigned int j;
- int ret = 0;
- struct xt_mtchk_param mtpar;
- struct xt_entry_match *ematch;
-
- e->counters.pcnt = xt_percpu_counter_alloc();
- if (IS_ERR_VALUE(e->counters.pcnt))
- return -ENOMEM;
- j = 0;
- mtpar.net = net;
- mtpar.table = name;
- mtpar.entryinfo = &e->ipv6;
- mtpar.hook_mask = e->comefrom;
- mtpar.family = NFPROTO_IPV6;
- xt_ematch_foreach(ematch, e) {
- ret = check_match(ematch, &mtpar);
- if (ret != 0)
- goto cleanup_matches;
- ++j;
- }
-
- ret = check_target(e, net, name);
- if (ret)
- goto cleanup_matches;
- return 0;
-
- cleanup_matches:
- xt_ematch_foreach(ematch, e) {
- if (j-- == 0)
- break;
- cleanup_match(ematch, net);
- }
-
- xt_percpu_counter_free(e->counters.pcnt);
-
- return ret;
-}
-
static int
translate_compat_table(struct net *net,
struct xt_table_info **pinfo,
@@ -1666,7 +1612,7 @@ translate_compat_table(struct net *net,
struct xt_table_info *newinfo, *info;
void *pos, *entry0, *entry1;
struct compat_ip6t_entry *iter0;
- struct ip6t_entry *iter1;
+ struct ip6t_replace repl;
unsigned int size;
int ret = 0;
@@ -1675,12 +1621,6 @@ translate_compat_table(struct net *net,
size = compatr->size;
info->number = compatr->num_entries;
- /* Init all hooks to impossible value. */
- for (i = 0; i < NF_INET_NUMHOOKS; i++) {
- info->hook_entry[i] = 0xFFFFFFFF;
- info->underflow[i] = 0xFFFFFFFF;
- }
-
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(AF_INET6);
@@ -1689,9 +1629,7 @@ translate_compat_table(struct net *net,
xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + compatr->size,
- compatr->hook_entry,
- compatr->underflow);
+ entry0 + compatr->size);
if (ret != 0)
goto out_unlock;
++j;
@@ -1704,23 +1642,6 @@ translate_compat_table(struct net *net,
goto out_unlock;
}
- /* Check hooks all assigned */
- for (i = 0; i < NF_INET_NUMHOOKS; i++) {
- /* Only hooks which are valid */
- if (!(compatr->valid_hooks & (1 << i)))
- continue;
- if (info->hook_entry[i] == 0xFFFFFFFF) {
- duprintf("Invalid hook entry %u %u\n",
- i, info->hook_entry[i]);
- goto out_unlock;
- }
- if (info->underflow[i] == 0xFFFFFFFF) {
- duprintf("Invalid underflow %u %u\n",
- i, info->underflow[i]);
- goto out_unlock;
- }
- }
-
ret = -ENOMEM;
newinfo = xt_alloc_table_info(size);
if (!newinfo)
@@ -1728,56 +1649,34 @@ translate_compat_table(struct net *net,
newinfo->number = compatr->num_entries;
for (i = 0; i < NF_INET_NUMHOOKS; i++) {
- newinfo->hook_entry[i] = info->hook_entry[i];
- newinfo->underflow[i] = info->underflow[i];
+ newinfo->hook_entry[i] = compatr->hook_entry[i];
+ newinfo->underflow[i] = compatr->underflow[i];
}
entry1 = newinfo->entries;
pos = entry1;
+ size = compatr->size;
xt_entry_foreach(iter0, entry0, compatr->size)
compat_copy_entry_from_user(iter0, &pos, &size,
newinfo, entry1);
+ /* all module references in entry0 are now gone. */
xt_compat_flush_offsets(AF_INET6);
xt_compat_unlock(AF_INET6);
- ret = -ELOOP;
- if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
- goto free_newinfo;
+ memcpy(&repl, compatr, sizeof(*compatr));
- i = 0;
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- ret = compat_check_entry(iter1, net, compatr->name);
- if (ret != 0)
- break;
- ++i;
- if (strcmp(ip6t_get_target(iter1)->u.user.name,
- XT_ERROR_TARGET) == 0)
- ++newinfo->stacksize;
- }
- if (ret) {
- /*
- * The first i matches need cleanup_entry (calls ->destroy)
- * because they had called ->check already. The other j-i
- * entries need only release.
- */
- int skip = i;
- j -= i;
- xt_entry_foreach(iter0, entry0, newinfo->size) {
- if (skip-- > 0)
- continue;
- if (j-- == 0)
- break;
- compat_release_entry(iter0);
- }
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- if (i-- == 0)
- break;
- cleanup_entry(iter1, net);
- }
- xt_free_table_info(newinfo);
- return ret;
+ for (i = 0; i < NF_INET_NUMHOOKS; i++) {
+ repl.hook_entry[i] = newinfo->hook_entry[i];
+ repl.underflow[i] = newinfo->underflow[i];
}
+ repl.num_counters = 0;
+ repl.counters = NULL;
+ repl.size = newinfo->size;
+ ret = translate_table(net, newinfo, entry1, &repl);
+ if (ret)
+ goto free_newinfo;
+
*pinfo = newinfo;
*pentry0 = entry1;
xt_free_table_info(info);
@@ -1785,17 +1684,16 @@ translate_compat_table(struct net *net,
free_newinfo:
xt_free_table_info(newinfo);
-out:
+ return ret;
+out_unlock:
+ xt_compat_flush_offsets(AF_INET6);
+ xt_compat_unlock(AF_INET6);
xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
}
return ret;
-out_unlock:
- xt_compat_flush_offsets(AF_INET6);
- xt_compat_unlock(AF_INET6);
- goto out;
}
static int
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -533,6 +533,7 @@ void xt_compat_match_from_user(struct xt
struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
int pad, off = xt_compat_match_offset(match);
u_int16_t msize = cm->u.user.match_size;
+ char name[sizeof(m->u.user.name)];
m = *dstptr;
memcpy(m, cm, sizeof(*cm));
@@ -546,6 +547,9 @@ void xt_compat_match_from_user(struct xt
msize += off;
m->u.user.match_size = msize;
+ strlcpy(name, match->name, sizeof(name));
+ module_put(match->me);
+ strncpy(m->u.user.name, name, sizeof(m->u.user.name));
*size += off;
*dstptr += msize;
@@ -763,6 +767,7 @@ void xt_compat_target_from_user(struct x
struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
int pad, off = xt_compat_target_offset(target);
u_int16_t tsize = ct->u.user.target_size;
+ char name[sizeof(t->u.user.name)];
t = *dstptr;
memcpy(t, ct, sizeof(*ct));
@@ -776,6 +781,9 @@ void xt_compat_target_from_user(struct x
tsize += off;
t->u.user.target_size = tsize;
+ strlcpy(name, target->name, sizeof(name));
+ module_put(target->me);
+ strncpy(t->u.user.name, name, sizeof(t->u.user.name));
*size += off;
*dstptr += tsize;

100
debian/patches/bugfix/all/netfilter-x_tables-don-t-move-to-non-existent-next-r.patch vendored Normal file
View File

@ -0,0 +1,100 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:21 +0200
Subject: netfilter: x_tables: don't move to non-existent next rule
Origin: https://git.kernel.org/linus/f24e230d257af1ad7476c6e81a8dc3127a74204e
Ben Hawkes says:
In the mark_source_chains function (net/ipv4/netfilter/ip_tables.c) it
is possible for a user-supplied ipt_entry structure to have a large
next_offset field. This field is not bounds checked prior to writing a
counter value at the supplied offset.
Base chains enforce absolute verdict.
User defined chains are supposed to end with an unconditional return,
xtables userspace adds them automatically.
But if such return is missing we will move to non-existent next rule.
Reported-by: Ben Hawkes <hawkes@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv4/netfilter/arp_tables.c | 8 +++++---
net/ipv4/netfilter/ip_tables.c | 4 ++++
net/ipv6/netfilter/ip6_tables.c | 4 ++++
3 files changed, 13 insertions(+), 3 deletions(-)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -439,6 +439,8 @@ static int mark_source_chains(const stru
size = e->next_offset;
e = (struct arpt_entry *)
(entry0 + pos + size);
+ if (pos + size >= newinfo->size)
+ return 0;
e->counters.pcnt = pos;
pos += size;
} else {
@@ -461,6 +463,8 @@ static int mark_source_chains(const stru
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
+ if (newpos >= newinfo->size)
+ return 0;
}
e = (struct arpt_entry *)
(entry0 + newpos);
@@ -691,10 +695,8 @@ static int translate_table(struct xt_tab
}
}
- if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) {
- duprintf("Looping hook\n");
+ if (!mark_source_chains(newinfo, repl->valid_hooks, entry0))
return -ELOOP;
- }
/* Finally, each sanity check must pass */
i = 0;
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -520,6 +520,8 @@ mark_source_chains(const struct xt_table
size = e->next_offset;
e = (struct ipt_entry *)
(entry0 + pos + size);
+ if (pos + size >= newinfo->size)
+ return 0;
e->counters.pcnt = pos;
pos += size;
} else {
@@ -541,6 +543,8 @@ mark_source_chains(const struct xt_table
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
+ if (newpos >= newinfo->size)
+ return 0;
}
e = (struct ipt_entry *)
(entry0 + newpos);
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -532,6 +532,8 @@ mark_source_chains(const struct xt_table
size = e->next_offset;
e = (struct ip6t_entry *)
(entry0 + pos + size);
+ if (pos + size >= newinfo->size)
+ return 0;
e->counters.pcnt = pos;
pos += size;
} else {
@@ -553,6 +555,8 @@ mark_source_chains(const struct xt_table
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
+ if (newpos >= newinfo->size)
+ return 0;
}
e = (struct ip6t_entry *)
(entry0 + newpos);

54
debian/patches/bugfix/all/netfilter-x_tables-don-t-reject-valid-target-size-on.patch vendored Normal file
View File

@ -0,0 +1,54 @@
From: Florian Westphal <fw@strlen.de>
Date: Wed, 1 Jun 2016 02:04:44 +0200
Subject: netfilter: x_tables: don't reject valid target size on some
architectures
Origin: https://git.kernel.org/linus/7b7eba0f3515fca3296b8881d583f7c1042f5226
Quoting John Stultz:
In updating a 32bit arm device from 4.6 to Linus' current HEAD, I
noticed I was having some trouble with networking, and realized that
/proc/net/ip_tables_names was suddenly empty.
Digging through the registration process, it seems we're catching on the:
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
target_offset + sizeof(struct xt_standard_target) != next_offset)
return -EINVAL;
Where next_offset seems to be 4 bytes larger then the
offset + standard_target struct size.
next_offset needs to be aligned via XT_ALIGN (so we can access all members
of ip(6)t_entry struct).
This problem didn't show up on i686 as it only needs 4-byte alignment for
u64, but iptables userspace on other 32bit arches does insert extra padding.
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Fixes: 7ed2abddd20cf ("netfilter: x_tables: check standard target size too")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/x_tables.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -609,7 +609,7 @@ int xt_compat_check_entry_offsets(const
return -EINVAL;
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
- target_offset + sizeof(struct compat_xt_standard_target) != next_offset)
+ COMPAT_XT_ALIGN(target_offset + sizeof(struct compat_xt_standard_target)) != next_offset)
return -EINVAL;
/* compat_xt_entry match has less strict aligment requirements,
@@ -691,7 +691,7 @@ int xt_check_entry_offsets(const void *b
return -EINVAL;
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
- target_offset + sizeof(struct xt_standard_target) != next_offset)
+ XT_ALIGN(target_offset + sizeof(struct xt_standard_target)) != next_offset)
return -EINVAL;
return xt_check_entry_match(elems, base + target_offset,

328
debian/patches/bugfix/all/netfilter-x_tables-introduce-and-use-xt_copy_counter.patch vendored Normal file
View File

@ -0,0 +1,328 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 15:37:59 +0200
Subject: netfilter: x_tables: introduce and use xt_copy_counters_from_user
Origin: https://git.kernel.org/linus/d7591f0c41ce3e67600a982bab6989ef0f07b3ce
The three variants use same copy&pasted code, condense this into a
helper and use that.
Make sure info.name is 0-terminated.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
include/linux/netfilter/x_tables.h | 3 ++
net/ipv4/netfilter/arp_tables.c | 48 +++----------------------
net/ipv4/netfilter/ip_tables.c | 48 +++----------------------
net/ipv6/netfilter/ip6_tables.c | 49 +++----------------------
net/netfilter/x_tables.c | 74 ++++++++++++++++++++++++++++++++++++++
5 files changed, 92 insertions(+), 130 deletions(-)
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -251,6 +251,9 @@ int xt_check_match(struct xt_mtchk_param
int xt_check_target(struct xt_tgchk_param *, unsigned int size, u_int8_t proto,
bool inv_proto);
+void *xt_copy_counters_from_user(const void __user *user, unsigned int len,
+ struct xt_counters_info *info, bool compat);
+
struct xt_table *xt_register_table(struct net *net,
const struct xt_table *table,
struct xt_table_info *bootstrap,
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -1131,55 +1131,17 @@ static int do_add_counters(struct net *n
unsigned int i;
struct xt_counters_info tmp;
struct xt_counters *paddc;
- unsigned int num_counters;
- const char *name;
- int size;
- void *ptmp;
struct xt_table *t;
const struct xt_table_info *private;
int ret = 0;
struct arpt_entry *iter;
unsigned int addend;
-#ifdef CONFIG_COMPAT
- struct compat_xt_counters_info compat_tmp;
- if (compat) {
- ptmp = &compat_tmp;
- size = sizeof(struct compat_xt_counters_info);
- } else
-#endif
- {
- ptmp = &tmp;
- size = sizeof(struct xt_counters_info);
- }
-
- if (copy_from_user(ptmp, user, size) != 0)
- return -EFAULT;
-
-#ifdef CONFIG_COMPAT
- if (compat) {
- num_counters = compat_tmp.num_counters;
- name = compat_tmp.name;
- } else
-#endif
- {
- num_counters = tmp.num_counters;
- name = tmp.name;
- }
-
- if (len != size + num_counters * sizeof(struct xt_counters))
- return -EINVAL;
-
- paddc = vmalloc(len - size);
- if (!paddc)
- return -ENOMEM;
-
- if (copy_from_user(paddc, user + size, len - size) != 0) {
- ret = -EFAULT;
- goto free;
- }
+ paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
+ if (IS_ERR(paddc))
+ return PTR_ERR(paddc);
- t = xt_find_table_lock(net, NFPROTO_ARP, name);
+ t = xt_find_table_lock(net, NFPROTO_ARP, tmp.name);
if (IS_ERR_OR_NULL(t)) {
ret = t ? PTR_ERR(t) : -ENOENT;
goto free;
@@ -1187,7 +1149,7 @@ static int do_add_counters(struct net *n
local_bh_disable();
private = t->private;
- if (private->number != num_counters) {
+ if (private->number != tmp.num_counters) {
ret = -EINVAL;
goto unlock_up_free;
}
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1314,55 +1314,17 @@ do_add_counters(struct net *net, const v
unsigned int i;
struct xt_counters_info tmp;
struct xt_counters *paddc;
- unsigned int num_counters;
- const char *name;
- int size;
- void *ptmp;
struct xt_table *t;
const struct xt_table_info *private;
int ret = 0;
struct ipt_entry *iter;
unsigned int addend;
-#ifdef CONFIG_COMPAT
- struct compat_xt_counters_info compat_tmp;
- if (compat) {
- ptmp = &compat_tmp;
- size = sizeof(struct compat_xt_counters_info);
- } else
-#endif
- {
- ptmp = &tmp;
- size = sizeof(struct xt_counters_info);
- }
-
- if (copy_from_user(ptmp, user, size) != 0)
- return -EFAULT;
-
-#ifdef CONFIG_COMPAT
- if (compat) {
- num_counters = compat_tmp.num_counters;
- name = compat_tmp.name;
- } else
-#endif
- {
- num_counters = tmp.num_counters;
- name = tmp.name;
- }
-
- if (len != size + num_counters * sizeof(struct xt_counters))
- return -EINVAL;
-
- paddc = vmalloc(len - size);
- if (!paddc)
- return -ENOMEM;
-
- if (copy_from_user(paddc, user + size, len - size) != 0) {
- ret = -EFAULT;
- goto free;
- }
+ paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
+ if (IS_ERR(paddc))
+ return PTR_ERR(paddc);
- t = xt_find_table_lock(net, AF_INET, name);
+ t = xt_find_table_lock(net, AF_INET, tmp.name);
if (IS_ERR_OR_NULL(t)) {
ret = t ? PTR_ERR(t) : -ENOENT;
goto free;
@@ -1370,7 +1332,7 @@ do_add_counters(struct net *net, const v
local_bh_disable();
private = t->private;
- if (private->number != num_counters) {
+ if (private->number != tmp.num_counters) {
ret = -EINVAL;
goto unlock_up_free;
}
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1326,55 +1326,16 @@ do_add_counters(struct net *net, const v
unsigned int i;
struct xt_counters_info tmp;
struct xt_counters *paddc;
- unsigned int num_counters;
- char *name;
- int size;
- void *ptmp;
struct xt_table *t;
const struct xt_table_info *private;
int ret = 0;
struct ip6t_entry *iter;
unsigned int addend;
-#ifdef CONFIG_COMPAT
- struct compat_xt_counters_info compat_tmp;
- if (compat) {
- ptmp = &compat_tmp;
- size = sizeof(struct compat_xt_counters_info);
- } else
-#endif
- {
- ptmp = &tmp;
- size = sizeof(struct xt_counters_info);
- }
-
- if (copy_from_user(ptmp, user, size) != 0)
- return -EFAULT;
-
-#ifdef CONFIG_COMPAT
- if (compat) {
- num_counters = compat_tmp.num_counters;
- name = compat_tmp.name;
- } else
-#endif
- {
- num_counters = tmp.num_counters;
- name = tmp.name;
- }
-
- if (len != size + num_counters * sizeof(struct xt_counters))
- return -EINVAL;
-
- paddc = vmalloc(len - size);
- if (!paddc)
- return -ENOMEM;
-
- if (copy_from_user(paddc, user + size, len - size) != 0) {
- ret = -EFAULT;
- goto free;
- }
-
- t = xt_find_table_lock(net, AF_INET6, name);
+ paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
+ if (IS_ERR(paddc))
+ return PTR_ERR(paddc);
+ t = xt_find_table_lock(net, AF_INET6, tmp.name);
if (IS_ERR_OR_NULL(t)) {
ret = t ? PTR_ERR(t) : -ENOENT;
goto free;
@@ -1382,7 +1343,7 @@ do_add_counters(struct net *net, const v
local_bh_disable();
private = t->private;
- if (private->number != num_counters) {
+ if (private->number != tmp.num_counters) {
ret = -EINVAL;
goto unlock_up_free;
}
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -752,6 +752,80 @@ int xt_check_target(struct xt_tgchk_para
}
EXPORT_SYMBOL_GPL(xt_check_target);
+/**
+ * xt_copy_counters_from_user - copy counters and metadata from userspace
+ *
+ * @user: src pointer to userspace memory
+ * @len: alleged size of userspace memory
+ * @info: where to store the xt_counters_info metadata
+ * @compat: true if we setsockopt call is done by 32bit task on 64bit kernel
+ *
+ * Copies counter meta data from @user and stores it in @info.
+ *
+ * vmallocs memory to hold the counters, then copies the counter data
+ * from @user to the new memory and returns a pointer to it.
+ *
+ * If @compat is true, @info gets converted automatically to the 64bit
+ * representation.
+ *
+ * The metadata associated with the counters is stored in @info.
+ *
+ * Return: returns pointer that caller has to test via IS_ERR().
+ * If IS_ERR is false, caller has to vfree the pointer.
+ */
+void *xt_copy_counters_from_user(const void __user *user, unsigned int len,
+ struct xt_counters_info *info, bool compat)
+{
+ void *mem;
+ u64 size;
+
+#ifdef CONFIG_COMPAT
+ if (compat) {
+ /* structures only differ in size due to alignment */
+ struct compat_xt_counters_info compat_tmp;
+
+ if (len <= sizeof(compat_tmp))
+ return ERR_PTR(-EINVAL);
+
+ len -= sizeof(compat_tmp);
+ if (copy_from_user(&compat_tmp, user, sizeof(compat_tmp)) != 0)
+ return ERR_PTR(-EFAULT);
+
+ strlcpy(info->name, compat_tmp.name, sizeof(info->name));
+ info->num_counters = compat_tmp.num_counters;
+ user += sizeof(compat_tmp);
+ } else
+#endif
+ {
+ if (len <= sizeof(*info))
+ return ERR_PTR(-EINVAL);
+
+ len -= sizeof(*info);
+ if (copy_from_user(info, user, sizeof(*info)) != 0)
+ return ERR_PTR(-EFAULT);
+
+ info->name[sizeof(info->name) - 1] = '\0';
+ user += sizeof(*info);
+ }
+
+ size = sizeof(struct xt_counters);
+ size *= info->num_counters;
+
+ if (size != (u64)len)
+ return ERR_PTR(-EINVAL);
+
+ mem = vmalloc(len);
+ if (!mem)
+ return ERR_PTR(-ENOMEM);
+
+ if (copy_from_user(mem, user, len) == 0)
+ return mem;
+
+ vfree(mem);
+ return ERR_PTR(-EFAULT);
+}
+EXPORT_SYMBOL_GPL(xt_copy_counters_from_user);
+
#ifdef CONFIG_COMPAT
int xt_compat_target_offset(const struct xt_target *target)
{

149
debian/patches/bugfix/all/netfilter-x_tables-kill-check_entry-helper.patch vendored Normal file
View File

@ -0,0 +1,149 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:24 +0200
Subject: netfilter: x_tables: kill check_entry helper
Origin: https://git.kernel.org/linus/aa412ba225dd3bc36d404c28cdc3d674850d80d0
Once we add more sanity testing to xt_check_entry_offsets it
becomes relvant if we're expecting a 32bit 'config_compat' blob
or a normal one.
Since we already have a lot of similar-named functions (check_entry,
compat_check_entry, find_and_check_entry, etc.) and the current
incarnation is short just fold its contents into the callers.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv4/netfilter/arp_tables.c | 19 ++++++++-----------
net/ipv4/netfilter/ip_tables.c | 20 ++++++++------------
net/ipv6/netfilter/ip6_tables.c | 20 ++++++++------------
3 files changed, 24 insertions(+), 35 deletions(-)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -494,14 +494,6 @@ next:
return 1;
}
-static inline int check_entry(const struct arpt_entry *e)
-{
- if (!arp_checkentry(&e->arp))
- return -EINVAL;
-
- return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
-}
-
static inline int check_target(struct arpt_entry *e, const char *name)
{
struct xt_entry_target *t = arpt_get_target(e);
@@ -597,7 +589,10 @@ static inline int check_entry_size_and_h
return -EINVAL;
}
- err = check_entry(e);
+ if (!arp_checkentry(&e->arp))
+ return -EINVAL;
+
+ err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (err)
return err;
@@ -1256,8 +1251,10 @@ check_compat_entry_size_and_hooks(struct
return -EINVAL;
}
- /* For purposes of check_entry casting the compat entry is fine */
- ret = check_entry((struct arpt_entry *)e);
+ if (!arp_checkentry(&e->arp))
+ return -EINVAL;
+
+ ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (ret)
return ret;
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -588,15 +588,6 @@ static void cleanup_match(struct xt_entr
}
static int
-check_entry(const struct ipt_entry *e)
-{
- if (!ip_checkentry(&e->ip))
- return -EINVAL;
-
- return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
-}
-
-static int
check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
{
const struct ipt_ip *ip = par->entryinfo;
@@ -760,7 +751,10 @@ check_entry_size_and_hooks(struct ipt_en
return -EINVAL;
}
- err = check_entry(e);
+ if (!ip_checkentry(&e->ip))
+ return -EINVAL;
+
+ err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (err)
return err;
@@ -1516,8 +1510,10 @@ check_compat_entry_size_and_hooks(struct
return -EINVAL;
}
- /* For purposes of check_entry casting the compat entry is fine */
- ret = check_entry((struct ipt_entry *)e);
+ if (!ip_checkentry(&e->ip))
+ return -EINVAL;
+
+ ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (ret)
return ret;
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -599,15 +599,6 @@ static void cleanup_match(struct xt_entr
module_put(par.match->me);
}
-static int
-check_entry(const struct ip6t_entry *e)
-{
- if (!ip6_checkentry(&e->ipv6))
- return -EINVAL;
-
- return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
-}
-
static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
{
const struct ip6t_ip6 *ipv6 = par->entryinfo;
@@ -772,7 +763,10 @@ check_entry_size_and_hooks(struct ip6t_e
return -EINVAL;
}
- err = check_entry(e);
+ if (!ip6_checkentry(&e->ipv6))
+ return -EINVAL;
+
+ err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (err)
return err;
@@ -1528,8 +1522,10 @@ check_compat_entry_size_and_hooks(struct
return -EINVAL;
}
- /* For purposes of check_entry casting the compat entry is fine */
- ret = check_entry((struct ip6t_entry *)e);
+ if (!ip6_checkentry(&e->ipv6))
+ return -EINVAL;
+
+ ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (ret)
return ret;

137
debian/patches/bugfix/all/netfilter-x_tables-validate-all-offsets-and-sizes-in.patch vendored Normal file
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@ -0,0 +1,137 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:29 +0200
Subject: netfilter: x_tables: validate all offsets and sizes in a rule
Origin: https://git.kernel.org/linus/13631bfc604161a9d69cd68991dff8603edd66f9
Validate that all matches (if any) add up to the beginning of
the target and that each match covers at least the base structure size.
The compat path should be able to safely re-use the function
as the structures only differ in alignment; added a
BUILD_BUG_ON just in case we have an arch that adds padding as well.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/x_tables.c | 81 +++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 76 insertions(+), 5 deletions(-)
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -416,6 +416,47 @@ int xt_check_match(struct xt_mtchk_param
}
EXPORT_SYMBOL_GPL(xt_check_match);
+/** xt_check_entry_match - check that matches end before start of target
+ *
+ * @match: beginning of xt_entry_match
+ * @target: beginning of this rules target (alleged end of matches)
+ * @alignment: alignment requirement of match structures
+ *
+ * Validates that all matches add up to the beginning of the target,
+ * and that each match covers at least the base structure size.
+ *
+ * Return: 0 on success, negative errno on failure.
+ */
+static int xt_check_entry_match(const char *match, const char *target,
+ const size_t alignment)
+{
+ const struct xt_entry_match *pos;
+ int length = target - match;
+
+ if (length == 0) /* no matches */
+ return 0;
+
+ pos = (struct xt_entry_match *)match;
+ do {
+ if ((unsigned long)pos % alignment)
+ return -EINVAL;
+
+ if (length < (int)sizeof(struct xt_entry_match))
+ return -EINVAL;
+
+ if (pos->u.match_size < sizeof(struct xt_entry_match))
+ return -EINVAL;
+
+ if (pos->u.match_size > length)
+ return -EINVAL;
+
+ length -= pos->u.match_size;
+ pos = ((void *)((char *)(pos) + (pos)->u.match_size));
+ } while (length > 0);
+
+ return 0;
+}
+
#ifdef CONFIG_COMPAT
int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
{
@@ -571,7 +612,14 @@ int xt_compat_check_entry_offsets(const
target_offset + sizeof(struct compat_xt_standard_target) != next_offset)
return -EINVAL;
- return 0;
+ /* compat_xt_entry match has less strict aligment requirements,
+ * otherwise they are identical. In case of padding differences
+ * we need to add compat version of xt_check_entry_match.
+ */
+ BUILD_BUG_ON(sizeof(struct compat_xt_entry_match) != sizeof(struct xt_entry_match));
+
+ return xt_check_entry_match(elems, base + target_offset,
+ __alignof__(struct compat_xt_entry_match));
}
EXPORT_SYMBOL(xt_compat_check_entry_offsets);
#endif /* CONFIG_COMPAT */
@@ -584,17 +632,39 @@ EXPORT_SYMBOL(xt_compat_check_entry_offs
* @target_offset: the arp/ip/ip6_t->target_offset
* @next_offset: the arp/ip/ip6_t->next_offset
*
- * validates that target_offset and next_offset are sane.
- * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version.
+ * validates that target_offset and next_offset are sane and that all
+ * match sizes (if any) align with the target offset.
*
* This function does not validate the targets or matches themselves, it
- * only tests that all the offsets and sizes are correct.
+ * only tests that all the offsets and sizes are correct, that all
+ * match structures are aligned, and that the last structure ends where
+ * the target structure begins.
+ *
+ * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version.
*
* The arp/ip/ip6t_entry structure @base must have passed following tests:
* - it must point to a valid memory location
* - base to base + next_offset must be accessible, i.e. not exceed allocated
* length.
*
+ * A well-formed entry looks like this:
+ *
+ * ip(6)t_entry match [mtdata] match [mtdata] target [tgdata] ip(6)t_entry
+ * e->elems[]-----' | |
+ * matchsize | |
+ * matchsize | |
+ * | |
+ * target_offset---------------------------------' |
+ * next_offset---------------------------------------------------'
+ *
+ * elems[]: flexible array member at end of ip(6)/arpt_entry struct.
+ * This is where matches (if any) and the target reside.
+ * target_offset: beginning of target.
+ * next_offset: start of the next rule; also: size of this rule.
+ * Since targets have a minimum size, target_offset + minlen <= next_offset.
+ *
+ * Every match stores its size, sum of sizes must not exceed target_offset.
+ *
* Return: 0 on success, negative errno on failure.
*/
int xt_check_entry_offsets(const void *base,
@@ -624,7 +694,8 @@ int xt_check_entry_offsets(const void *b
target_offset + sizeof(struct xt_standard_target) != next_offset)
return -EINVAL;
- return 0;
+ return xt_check_entry_match(elems, base + target_offset,
+ __alignof__(struct xt_entry_match));
}
EXPORT_SYMBOL(xt_check_entry_offsets);

127
debian/patches/bugfix/all/netfilter-x_tables-validate-targets-of-jumps.patch vendored Normal file
View File

@ -0,0 +1,127 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:22 +0200
Subject: netfilter: x_tables: validate targets of jumps
Origin: https://git.kernel.org/linus/36472341017529e2b12573093cc0f68719300997
When we see a jump also check that the offset gets us to beginning of
a rule (an ipt_entry).
The extra overhead is negible, even with absurd cases.
300k custom rules, 300k jumps to 'next' user chain:
[ plus one jump from INPUT to first userchain ]:
Before:
real 0m24.874s
user 0m7.532s
sys 0m16.076s
After:
real 0m27.464s
user 0m7.436s
sys 0m18.840s
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/ipv4/netfilter/arp_tables.c | 16 ++++++++++++++++
net/ipv4/netfilter/ip_tables.c | 16 ++++++++++++++++
net/ipv6/netfilter/ip6_tables.c | 16 ++++++++++++++++
3 files changed, 48 insertions(+)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -367,6 +367,18 @@ static inline bool unconditional(const s
memcmp(&e->arp, &uncond, sizeof(uncond)) == 0;
}
+static bool find_jump_target(const struct xt_table_info *t,
+ const struct arpt_entry *target)
+{
+ struct arpt_entry *iter;
+
+ xt_entry_foreach(iter, t->entries, t->size) {
+ if (iter == target)
+ return true;
+ }
+ return false;
+}
+
/* Figures out from what hook each rule can be called: returns 0 if
* there are loops. Puts hook bitmask in comefrom.
*/
@@ -460,6 +472,10 @@ static int mark_source_chains(const stru
/* This a jump; chase it. */
duprintf("Jump rule %u -> %u\n",
pos, newpos);
+ e = (struct arpt_entry *)
+ (entry0 + newpos);
+ if (!find_jump_target(newinfo, e))
+ return 0;
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -443,6 +443,18 @@ ipt_do_table(struct sk_buff *skb,
#endif
}
+static bool find_jump_target(const struct xt_table_info *t,
+ const struct ipt_entry *target)
+{
+ struct ipt_entry *iter;
+
+ xt_entry_foreach(iter, t->entries, t->size) {
+ if (iter == target)
+ return true;
+ }
+ return false;
+}
+
/* Figures out from what hook each rule can be called: returns 0 if
there are loops. Puts hook bitmask in comefrom. */
static int
@@ -540,6 +552,10 @@ mark_source_chains(const struct xt_table
/* This a jump; chase it. */
duprintf("Jump rule %u -> %u\n",
pos, newpos);
+ e = (struct ipt_entry *)
+ (entry0 + newpos);
+ if (!find_jump_target(newinfo, e))
+ return 0;
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -455,6 +455,18 @@ ip6t_do_table(struct sk_buff *skb,
#endif
}
+static bool find_jump_target(const struct xt_table_info *t,
+ const struct ip6t_entry *target)
+{
+ struct ip6t_entry *iter;
+
+ xt_entry_foreach(iter, t->entries, t->size) {
+ if (iter == target)
+ return true;
+ }
+ return false;
+}
+
/* Figures out from what hook each rule can be called: returns 0 if
there are loops. Puts hook bitmask in comefrom. */
static int
@@ -552,6 +564,10 @@ mark_source_chains(const struct xt_table
/* This a jump; chase it. */
duprintf("Jump rule %u -> %u\n",
pos, newpos);
+ e = (struct ip6t_entry *)
+ (entry0 + newpos);
+ if (!find_jump_target(newinfo, e))
+ return 0;
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;

234
debian/patches/bugfix/all/netfilter-x_tables-xt_compat_match_from_user-doesn-t.patch vendored Normal file
View File

@ -0,0 +1,234 @@
From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 14:17:33 +0200
Subject: netfilter: x_tables: xt_compat_match_from_user doesn't need a retval
Origin: https://git.kernel.org/linus/0188346f21e6546498c2a0f84888797ad4063fc5
Always returned 0.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
include/linux/netfilter/x_tables.h | 2 +-
net/ipv4/netfilter/arp_tables.c | 17 +++++------------
net/ipv4/netfilter/ip_tables.c | 26 +++++++++-----------------
net/ipv6/netfilter/ip6_tables.c | 27 +++++++++------------------
net/netfilter/x_tables.c | 5 ++---
5 files changed, 26 insertions(+), 51 deletions(-)
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -484,7 +484,7 @@ void xt_compat_init_offsets(u_int8_t af,
int xt_compat_calc_jump(u_int8_t af, unsigned int offset);
int xt_compat_match_offset(const struct xt_match *match);
-int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
+void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
unsigned int *size);
int xt_compat_match_to_user(const struct xt_entry_match *m,
void __user **dstptr, unsigned int *size);
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -1310,7 +1310,7 @@ out:
return ret;
}
-static int
+static void
compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
@@ -1319,9 +1319,8 @@ compat_copy_entry_from_user(struct compa
struct xt_target *target;
struct arpt_entry *de;
unsigned int origsize;
- int ret, h;
+ int h;
- ret = 0;
origsize = *size;
de = (struct arpt_entry *)*dstptr;
memcpy(de, e, sizeof(struct arpt_entry));
@@ -1342,7 +1341,6 @@ compat_copy_entry_from_user(struct compa
if ((unsigned char *)de - base < newinfo->underflow[h])
newinfo->underflow[h] -= origsize - *size;
}
- return ret;
}
static int translate_compat_table(struct xt_table_info **pinfo,
@@ -1421,16 +1419,11 @@ static int translate_compat_table(struct
entry1 = newinfo->entries;
pos = entry1;
size = compatr->size;
- xt_entry_foreach(iter0, entry0, compatr->size) {
- ret = compat_copy_entry_from_user(iter0, &pos, &size,
- newinfo, entry1);
- if (ret != 0)
- break;
- }
+ xt_entry_foreach(iter0, entry0, compatr->size)
+ compat_copy_entry_from_user(iter0, &pos, &size,
+ newinfo, entry1);
xt_compat_flush_offsets(NFPROTO_ARP);
xt_compat_unlock(NFPROTO_ARP);
- if (ret)
- goto free_newinfo;
ret = -ELOOP;
if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1568,7 +1568,7 @@ release_matches:
return ret;
}
-static int
+static void
compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
@@ -1577,10 +1577,9 @@ compat_copy_entry_from_user(struct compa
struct xt_target *target;
struct ipt_entry *de;
unsigned int origsize;
- int ret, h;
+ int h;
struct xt_entry_match *ematch;
- ret = 0;
origsize = *size;
de = (struct ipt_entry *)*dstptr;
memcpy(de, e, sizeof(struct ipt_entry));
@@ -1589,11 +1588,9 @@ compat_copy_entry_from_user(struct compa
*dstptr += sizeof(struct ipt_entry);
*size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
- xt_ematch_foreach(ematch, e) {
- ret = xt_compat_match_from_user(ematch, dstptr, size);
- if (ret != 0)
- return ret;
- }
+ xt_ematch_foreach(ematch, e)
+ xt_compat_match_from_user(ematch, dstptr, size);
+
de->target_offset = e->target_offset - (origsize - *size);
t = compat_ipt_get_target(e);
target = t->u.kernel.target;
@@ -1606,7 +1603,6 @@ compat_copy_entry_from_user(struct compa
if ((unsigned char *)de - base < newinfo->underflow[h])
newinfo->underflow[h] -= origsize - *size;
}
- return ret;
}
static int
@@ -1729,16 +1725,12 @@ translate_compat_table(struct net *net,
entry1 = newinfo->entries;
pos = entry1;
size = compatr->size;
- xt_entry_foreach(iter0, entry0, compatr->size) {
- ret = compat_copy_entry_from_user(iter0, &pos, &size,
- newinfo, entry1);
- if (ret != 0)
- break;
- }
+ xt_entry_foreach(iter0, entry0, compatr->size)
+ compat_copy_entry_from_user(iter0, &pos, &size,
+ newinfo, entry1);
+
xt_compat_flush_offsets(AF_INET);
xt_compat_unlock(AF_INET);
- if (ret)
- goto free_newinfo;
ret = -ELOOP;
if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1580,7 +1580,7 @@ release_matches:
return ret;
}
-static int
+static void
compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
@@ -1588,10 +1588,9 @@ compat_copy_entry_from_user(struct compa
struct xt_entry_target *t;
struct ip6t_entry *de;
unsigned int origsize;
- int ret, h;
+ int h;
struct xt_entry_match *ematch;
- ret = 0;
origsize = *size;
de = (struct ip6t_entry *)*dstptr;
memcpy(de, e, sizeof(struct ip6t_entry));
@@ -1600,11 +1599,9 @@ compat_copy_entry_from_user(struct compa
*dstptr += sizeof(struct ip6t_entry);
*size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
- xt_ematch_foreach(ematch, e) {
- ret = xt_compat_match_from_user(ematch, dstptr, size);
- if (ret != 0)
- return ret;
- }
+ xt_ematch_foreach(ematch, e)
+ xt_compat_match_from_user(ematch, dstptr, size);
+
de->target_offset = e->target_offset - (origsize - *size);
t = compat_ip6t_get_target(e);
xt_compat_target_from_user(t, dstptr, size);
@@ -1616,7 +1613,6 @@ compat_copy_entry_from_user(struct compa
if ((unsigned char *)de - base < newinfo->underflow[h])
newinfo->underflow[h] -= origsize - *size;
}
- return ret;
}
static int compat_check_entry(struct ip6t_entry *e, struct net *net,
@@ -1737,17 +1733,12 @@ translate_compat_table(struct net *net,
}
entry1 = newinfo->entries;
pos = entry1;
- size = compatr->size;
- xt_entry_foreach(iter0, entry0, compatr->size) {
- ret = compat_copy_entry_from_user(iter0, &pos, &size,
- newinfo, entry1);
- if (ret != 0)
- break;
- }
+ xt_entry_foreach(iter0, entry0, compatr->size)
+ compat_copy_entry_from_user(iter0, &pos, &size,
+ newinfo, entry1);
+
xt_compat_flush_offsets(AF_INET6);
xt_compat_unlock(AF_INET6);
- if (ret)
- goto free_newinfo;
ret = -ELOOP;
if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -526,8 +526,8 @@ int xt_compat_match_offset(const struct
}
EXPORT_SYMBOL_GPL(xt_compat_match_offset);
-int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
- unsigned int *size)
+void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
+ unsigned int *size)
{
const struct xt_match *match = m->u.kernel.match;
struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
@@ -549,7 +549,6 @@ int xt_compat_match_from_user(struct xt_
*size += off;
*dstptr += msize;
- return 0;
}
EXPORT_SYMBOL_GPL(xt_compat_match_from_user);

16
debian/patches/series vendored
View File

@ -115,6 +115,22 @@ bugfix/all/rds-fix-an-infoleak-in-rds_inc_info_copy.patch
bugfix/all/keys-potential-uninitialized-variable.patch
bugfix/all/percpu-fix-synchronization-between-chunk-map_extend_.patch
bugfix/all/percpu-fix-synchronization-between-synchronous-map-e.patch
bugfix/all/netfilter-x_tables-don-t-move-to-non-existent-next-r.patch
bugfix/all/netfilter-x_tables-validate-targets-of-jumps.patch
bugfix/all/netfilter-x_tables-add-and-use-xt_check_entry_offset.patch
bugfix/all/netfilter-x_tables-kill-check_entry-helper.patch
bugfix/all/netfilter-x_tables-assert-minimum-target-size.patch
bugfix/all/netfilter-x_tables-add-compat-version-of-xt_check_en.patch
bugfix/all/netfilter-x_tables-check-standard-target-size-too.patch
bugfix/all/netfilter-x_tables-check-for-bogus-target-offset.patch
bugfix/all/netfilter-x_tables-validate-all-offsets-and-sizes-in.patch
bugfix/all/netfilter-x_tables-don-t-reject-valid-target-size-on.patch
bugfix/all/netfilter-arp_tables-simplify-translate_compat_table.patch
bugfix/all/netfilter-ip_tables-simplify-translate_compat_table-.patch
bugfix/all/netfilter-ip6_tables-simplify-translate_compat_table.patch
bugfix/all/netfilter-x_tables-xt_compat_match_from_user-doesn-t.patch
bugfix/all/netfilter-x_tables-do-compat-validation-via-translat.patch
bugfix/all/netfilter-x_tables-introduce-and-use-xt_copy_counter.patch
# ABI maintenance
debian/mips-siginfo-fix-abi-change-in-4.6.2.patch