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netfilter: xtables: change hotdrop pointer to direct modification

Browse source 
Since xt_action_param is writable, let's use it. The pointer to
'bool hotdrop' always worried (8 bytes (64-bit) to write 1 byte!).
Surprisingly results in a reduction in size:

   text    data     bss filename
5457066  692730  357892 vmlinux.o-prev
5456554  692730  357892 vmlinux.o

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
This commit is contained in:
Jan Engelhardt 2009-07-07 20:54:30 +02:00
parent 62fc805108
commit b4ba26119b
22 changed files with 47 additions and 47 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
include/linux/netfilter/x_tables.h
View file

@ -196,6 +196,9 @@ struct xt_counters_info {
* @hook: hook number given packet came from
* @family: Actual NFPROTO_* through which the function is invoked
* (helpful when match->family == NFPROTO_UNSPEC)
*
* Fields written to by extensions:
*
* @hotdrop: drop packet if we had inspection problems
* Network namespace obtainable using dev_net(in/out)
*/
@ -212,7 +215,7 @@ struct xt_action_param {
unsigned int thoff;
unsigned int hooknum;
u_int8_t family;
bool *hotdrop;
bool hotdrop;
};
/**

5
net/bridge/netfilter/ebtables.c
View file

@ -186,13 +186,12 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb,
struct ebt_entries *chaininfo;
const char *base;
const struct ebt_table_info *private;
bool hotdrop = false;
struct xt_action_param acpar;
acpar.family = NFPROTO_BRIDGE;
acpar.in = in;
acpar.out = out;
acpar.hotdrop = &hotdrop;
acpar.hotdrop = false;
acpar.hooknum = hook;
read_lock_bh(&table->lock);
@ -216,7 +215,7 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb,
if (EBT_MATCH_ITERATE(point, ebt_do_match, skb, &acpar) != 0)
goto letscontinue;
if (hotdrop) {
if (acpar.hotdrop) {
read_unlock_bh(&table->lock);
return NF_DROP;
}

6
net/ipv4/netfilter/arp_tables.c
View file

@ -260,7 +260,6 @@ unsigned int arpt_do_table(struct sk_buff *skb,
static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
unsigned int verdict = NF_DROP;
const struct arphdr *arp;
bool hotdrop = false;
struct arpt_entry *e, *back;
const char *indev, *outdev;
void *table_base;
@ -284,6 +283,7 @@ unsigned int arpt_do_table(struct sk_buff *skb,
acpar.out = out;
acpar.hooknum = hook;
acpar.family = NFPROTO_ARP;
acpar.hotdrop = false;
arp = arp_hdr(skb);
do {
@ -345,10 +345,10 @@ unsigned int arpt_do_table(struct sk_buff *skb,
else
/* Verdict */
break;
} while (!hotdrop);
} while (!acpar.hotdrop);
xt_info_rdunlock_bh();
if (hotdrop)
if (acpar.hotdrop)
return NF_DROP;
else
return verdict;

9
net/ipv4/netfilter/ip_tables.c
View file

@ -308,7 +308,6 @@ ipt_do_table(struct sk_buff *skb,
{
static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
const struct iphdr *ip;
bool hotdrop = false;
/* Initializing verdict to NF_DROP keeps gcc happy. */
unsigned int verdict = NF_DROP;
const char *indev, *outdev;
@ -330,7 +329,7 @@ ipt_do_table(struct sk_buff *skb,
* match it. */
acpar.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
acpar.thoff = ip_hdrlen(skb);
acpar.hotdrop = &hotdrop;
acpar.hotdrop = false;
acpar.in = in;
acpar.out = out;
acpar.family = NFPROTO_IPV4;
@ -432,7 +431,7 @@ ipt_do_table(struct sk_buff *skb,
else
/* Verdict */
break;
} while (!hotdrop);
} while (!acpar.hotdrop);
xt_info_rdunlock_bh();
pr_debug("Exiting %s; resetting sp from %u to %u\n",
__func__, *stackptr, origptr);
@ -440,7 +439,7 @@ ipt_do_table(struct sk_buff *skb,
#ifdef DEBUG_ALLOW_ALL
return NF_ACCEPT;
#else
if (hotdrop)
if (acpar.hotdrop)
return NF_DROP;
else return verdict;
#endif
@ -2154,7 +2153,7 @@ icmp_match(const struct sk_buff *skb, struct xt_action_param *par)
* can't. Hence, no choice but to drop.
*/
duprintf("Dropping evil ICMP tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

2
net/ipv4/netfilter/ipt_ah.c
View file

@ -46,7 +46,7 @@ static bool ah_mt(const struct sk_buff *skb, struct xt_action_param *par)
* can't. Hence, no choice but to drop.
*/
pr_debug("Dropping evil AH tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return 0;
}

2
net/ipv4/netfilter/ipt_ecn.c
View file

@ -78,7 +78,7 @@ static bool ecn_mt(const struct sk_buff *skb, struct xt_action_param *par)
if (info->operation & (IPT_ECN_OP_MATCH_ECE|IPT_ECN_OP_MATCH_CWR)) {
if (ip_hdr(skb)->protocol != IPPROTO_TCP)
return false;
if (!match_tcp(skb, info, par->hotdrop))
if (!match_tcp(skb, info, &par->hotdrop))
return false;
}

11
net/ipv6/netfilter/ip6_tables.c
View file

@ -337,7 +337,6 @@ ip6t_do_table(struct sk_buff *skb,
struct xt_table *table)
{
static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
bool hotdrop = false;
/* Initializing verdict to NF_DROP keeps gcc happy. */
unsigned int verdict = NF_DROP;
const char *indev, *outdev;
@ -356,7 +355,7 @@ ip6t_do_table(struct sk_buff *skb,
* things we don't know, ie. tcp syn flag or ports). If the
* rule is also a fragment-specific rule, non-fragments won't
* match it. */
acpar.hotdrop = &hotdrop;
acpar.hotdrop = false;
acpar.in = in;
acpar.out = out;
acpar.family = NFPROTO_IPV6;
@ -380,7 +379,7 @@ ip6t_do_table(struct sk_buff *skb,
IP_NF_ASSERT(e);
if (!ip6_packet_match(skb, indev, outdev, &e->ipv6,
&acpar.thoff, &acpar.fragoff, &hotdrop)) {
&acpar.thoff, &acpar.fragoff, &acpar.hotdrop)) {
no_match:
e = ip6t_next_entry(e);
continue;
@ -447,7 +446,7 @@ ip6t_do_table(struct sk_buff *skb,
else
/* Verdict */
break;
} while (!hotdrop);
} while (!acpar.hotdrop);
xt_info_rdunlock_bh();
*stackptr = origptr;
@ -455,7 +454,7 @@ ip6t_do_table(struct sk_buff *skb,
#ifdef DEBUG_ALLOW_ALL
return NF_ACCEPT;
#else
if (hotdrop)
if (acpar.hotdrop)
return NF_DROP;
else return verdict;
#endif
@ -2170,7 +2169,7 @@ icmp6_match(const struct sk_buff *skb, struct xt_action_param *par)
* can't. Hence, no choice but to drop.
*/
duprintf("Dropping evil ICMP tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/ipv6/netfilter/ip6t_ah.c
View file

@ -48,13 +48,13 @@ static bool ah_mt6(const struct sk_buff *skb, struct xt_action_param *par)
err = ipv6_find_hdr(skb, &ptr, NEXTHDR_AUTH, NULL);
if (err < 0) {
if (err != -ENOENT)
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
ah = skb_header_pointer(skb, ptr, sizeof(_ah), &_ah);
if (ah == NULL) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

2
net/ipv6/netfilter/ip6t_eui64.c
View file

@ -27,7 +27,7 @@ eui64_mt6(const struct sk_buff *skb, struct xt_action_param *par)
if (!(skb_mac_header(skb) >= skb->head &&
skb_mac_header(skb) + ETH_HLEN <= skb->data) &&
par->fragoff != 0) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/ipv6/netfilter/ip6t_frag.c
View file

@ -46,13 +46,13 @@ frag_mt6(const struct sk_buff *skb, struct xt_action_param *par)
err = ipv6_find_hdr(skb, &ptr, NEXTHDR_FRAGMENT, NULL);
if (err < 0) {
if (err != -ENOENT)
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
fh = skb_header_pointer(skb, ptr, sizeof(_frag), &_frag);
if (fh == NULL) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/ipv6/netfilter/ip6t_hbh.c
View file

@ -65,13 +65,13 @@ hbh_mt6(const struct sk_buff *skb, struct xt_action_param *par)
NEXTHDR_HOP : NEXTHDR_DEST, NULL);
if (err < 0) {
if (err != -ENOENT)
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh);
if (oh == NULL) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/ipv6/netfilter/ip6t_mh.c
View file

@ -47,14 +47,14 @@ static bool mh_mt6(const struct sk_buff *skb, struct xt_action_param *par)
/* We've been asked to examine this packet, and we
can't. Hence, no choice but to drop. */
pr_debug("Dropping evil MH tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
if (mh->ip6mh_proto != IPPROTO_NONE) {
pr_debug("Dropping invalid MH Payload Proto: %u\n",
mh->ip6mh_proto);
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/ipv6/netfilter/ip6t_rt.c
View file

@ -52,13 +52,13 @@ static bool rt_mt6(const struct sk_buff *skb, struct xt_action_param *par)
err = ipv6_find_hdr(skb, &ptr, NEXTHDR_ROUTING, NULL);
if (err < 0) {
if (err != -ENOENT)
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
rh = skb_header_pointer(skb, ptr, sizeof(_route), &_route);
if (rh == NULL) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/netfilter/xt_connlimit.c
View file

@ -206,14 +206,14 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
if (connections < 0) {
/* kmalloc failed, drop it entirely */
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
return (connections > info->limit) ^ info->inverse;
hotdrop:
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

4
net/netfilter/xt_dccp.c
View file

@ -107,7 +107,7 @@ dccp_mt(const struct sk_buff *skb, struct xt_action_param *par)
dh = skb_header_pointer(skb, par->thoff, sizeof(_dh), &_dh);
if (dh == NULL) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
@ -120,7 +120,7 @@ dccp_mt(const struct sk_buff *skb, struct xt_action_param *par)
&& DCCHECK(match_types(dh, info->typemask),
XT_DCCP_TYPE, info->flags, info->invflags)
&& DCCHECK(match_option(info->option, skb, par->thoff, dh,
par->hotdrop),
&par->hotdrop),
XT_DCCP_OPTION, info->flags, info->invflags);
}

2
net/netfilter/xt_esp.c
View file

@ -52,7 +52,7 @@ static bool esp_mt(const struct sk_buff *skb, struct xt_action_param *par)
* can't. Hence, no choice but to drop.
*/
pr_debug("Dropping evil ESP tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

2
net/netfilter/xt_hashlimit.c
View file

@ -562,7 +562,7 @@ hashlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
return info->cfg.mode & XT_HASHLIMIT_INVERT;
hotdrop:
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

2
net/netfilter/xt_multiport.c
View file

@ -87,7 +87,7 @@ multiport_mt(const struct sk_buff *skb, struct xt_action_param *par)
* can't. Hence, no choice but to drop.
*/
pr_debug("Dropping evil offset=0 tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

2
net/netfilter/xt_recent.c
View file

@ -268,7 +268,7 @@ recent_mt(const struct sk_buff *skb, struct xt_action_param *par)
goto out;
e = recent_entry_init(t, &addr, par->family, ttl);
if (e == NULL)
*par->hotdrop = true;
par->hotdrop = true;
ret = !ret;
goto out;
}

4
net/netfilter/xt_sctp.c
View file

@ -128,7 +128,7 @@ sctp_mt(const struct sk_buff *skb, struct xt_action_param *par)
sh = skb_header_pointer(skb, par->thoff, sizeof(_sh), &_sh);
if (sh == NULL) {
pr_debug("Dropping evil TCP offset=0 tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
pr_debug("spt: %d\tdpt: %d\n", ntohs(sh->source), ntohs(sh->dest));
@ -140,7 +140,7 @@ sctp_mt(const struct sk_buff *skb, struct xt_action_param *par)
&& ntohs(sh->dest) <= info->dpts[1],
XT_SCTP_DEST_PORTS, info->flags, info->invflags)
&& SCCHECK(match_packet(skb, par->thoff + sizeof(sctp_sctphdr_t),
info, par->hotdrop),
info, &par->hotdrop),
XT_SCTP_CHUNK_TYPES, info->flags, info->invflags);
}

2
net/netfilter/xt_tcpmss.c
View file

@ -73,7 +73,7 @@ out:
return info->invert;
dropit:
*par->hotdrop = true;
par->hotdrop = true;
return false;
}

10
net/netfilter/xt_tcpudp.c
View file

@ -77,7 +77,7 @@ static bool tcp_mt(const struct sk_buff *skb, struct xt_action_param *par)
*/
if (par->fragoff == 1) {
pr_debug("Dropping evil TCP offset=1 frag.\n");
*par->hotdrop = true;
par->hotdrop = true;
}
/* Must not be a fragment. */
return false;
@ -90,7 +90,7 @@ static bool tcp_mt(const struct sk_buff *skb, struct xt_action_param *par)
/* We've been asked to examine this packet, and we
can't. Hence, no choice but to drop. */
pr_debug("Dropping evil TCP offset=0 tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
@ -108,13 +108,13 @@ static bool tcp_mt(const struct sk_buff *skb, struct xt_action_param *par)
return false;
if (tcpinfo->option) {
if (th->doff * 4 < sizeof(_tcph)) {
*par->hotdrop = true;
par->hotdrop = true;
return false;
}
if (!tcp_find_option(tcpinfo->option, skb, par->thoff,
th->doff*4 - sizeof(_tcph),
tcpinfo->invflags & XT_TCP_INV_OPTION,
par->hotdrop))
&par->hotdrop))
return false;
}
return true;
@ -143,7 +143,7 @@ static bool udp_mt(const struct sk_buff *skb, struct xt_action_param *par)
/* We've been asked to examine this packet, and we
can't. Hence, no choice but to drop. */
pr_debug("Dropping evil UDP tinygram.\n");
*par->hotdrop = true;
par->hotdrop = true;
return false;
}