[PATCH 3.10 017/180] netfilter: ip_tables: simplify translate_compat_table args

From: Willy Tarreau
Date: Sun Aug 21 2016 - 11:33:00 EST


From: Florian Westphal <fw@xxxxxxxxx>

commit 7d3f843eed29222254c9feab481f55175a1afcc9 upstream.

Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
net/ipv4/netfilter/ip_tables.c | 61 +++++++++++++++++-------------------------
1 file changed, 25 insertions(+), 36 deletions(-)

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 29f3092..ddfc3ac 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1439,7 +1439,6 @@ compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,

static int
compat_find_calc_match(struct xt_entry_match *m,
- const char *name,
const struct ipt_ip *ip,
unsigned int hookmask,
int *size)
@@ -1477,8 +1476,7 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
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;
@@ -1514,8 +1512,8 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
entry_offset = (void *)e - (void *)base;
j = 0;
xt_ematch_foreach(ematch, e) {
- ret = compat_find_calc_match(ematch, name,
- &e->ip, e->comefrom, &off);
+ ret = compat_find_calc_match(ematch, &e->ip, e->comefrom,
+ &off);
if (ret != 0)
goto release_matches;
++j;
@@ -1564,7 +1562,7 @@ 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;
@@ -1640,14 +1638,9 @@ compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)

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;
@@ -1659,8 +1652,8 @@ 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++) {
@@ -1671,40 +1664,39 @@ 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;
}
}
@@ -1714,17 +1706,17 @@ 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[raw_smp_processor_id()];
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;
}
@@ -1734,12 +1726,12 @@ 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;
@@ -1784,7 +1776,7 @@ 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);
@@ -1827,10 +1819,7 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len)
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;

--
2.8.0.rc2.1.gbe9624a