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Diffstat (limited to 'net/ipv4/cipso_ipv4.c')
-rw-r--r--net/ipv4/cipso_ipv4.c122
1 files changed, 77 insertions, 45 deletions
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 62d5f99760aa..709021197e1c 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -37,7 +37,7 @@
#include <net/cipso_ipv4.h>
#include <linux/atomic.h>
#include <linux/bug.h>
-#include <asm/unaligned.h>
+#include <linux/unaligned.h>
/* List of available DOI definitions */
/* XXX - This currently assumes a minimal number of different DOIs in use,
@@ -239,7 +239,7 @@ static int cipso_v4_cache_check(const unsigned char *key,
struct cipso_v4_map_cache_entry *prev_entry = NULL;
u32 hash;
- if (!cipso_v4_cache_enabled)
+ if (!READ_ONCE(cipso_v4_cache_enabled))
return -ENOENT;
hash = cipso_v4_map_cache_hash(key, key_len);
@@ -296,13 +296,14 @@ static int cipso_v4_cache_check(const unsigned char *key,
int cipso_v4_cache_add(const unsigned char *cipso_ptr,
const struct netlbl_lsm_secattr *secattr)
{
+ int bkt_size = READ_ONCE(cipso_v4_cache_bucketsize);
int ret_val = -EPERM;
u32 bkt;
struct cipso_v4_map_cache_entry *entry = NULL;
struct cipso_v4_map_cache_entry *old_entry = NULL;
u32 cipso_ptr_len;
- if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0)
+ if (!READ_ONCE(cipso_v4_cache_enabled) || bkt_size <= 0)
return 0;
cipso_ptr_len = cipso_ptr[1];
@@ -322,7 +323,7 @@ int cipso_v4_cache_add(const unsigned char *cipso_ptr,
bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1);
spin_lock_bh(&cipso_v4_cache[bkt].lock);
- if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
+ if (cipso_v4_cache[bkt].size < bkt_size) {
list_add(&entry->list, &cipso_v4_cache[bkt].list);
cipso_v4_cache[bkt].size += 1;
} else {
@@ -863,11 +864,8 @@ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
net_clen_bits,
net_spot + 1,
1);
- if (net_spot < 0) {
- if (net_spot == -2)
- return -EFAULT;
+ if (net_spot < 0)
return 0;
- }
switch (doi_def->type) {
case CIPSO_V4_MAP_PASS:
@@ -1199,7 +1197,8 @@ static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
/* This will send packets using the "optimized" format when
* possible as specified in section 3.4.2.6 of the
* CIPSO draft. */
- if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
+ if (READ_ONCE(cipso_v4_rbm_optfmt) && ret_val > 0 &&
+ ret_val <= 10)
tag_len = 14;
else
tag_len = 4 + ret_val;
@@ -1603,7 +1602,7 @@ int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
* all the CIPSO validations here but it doesn't
* really specify _exactly_ what we need to validate
* ... so, just make it a sysctl tunable. */
- if (cipso_v4_rbm_strictvalid) {
+ if (READ_ONCE(cipso_v4_rbm_strictvalid)) {
if (cipso_v4_map_lvl_valid(doi_def,
tag[3]) < 0) {
err_offset = opt_iter + 3;
@@ -1716,8 +1715,7 @@ validate_return:
*/
void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway)
{
- unsigned char optbuf[sizeof(struct ip_options) + 40];
- struct ip_options *opt = (struct ip_options *)optbuf;
+ struct inet_skb_parm parm;
int res;
if (ip_hdr(skb)->protocol == IPPROTO_ICMP || error != -EACCES)
@@ -1728,19 +1726,19 @@ void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway)
* so we can not use icmp_send and IPCB here.
*/
- memset(opt, 0, sizeof(struct ip_options));
- opt->optlen = ip_hdr(skb)->ihl*4 - sizeof(struct iphdr);
+ memset(&parm, 0, sizeof(parm));
+ parm.opt.optlen = ip_hdr(skb)->ihl * 4 - sizeof(struct iphdr);
rcu_read_lock();
- res = __ip_options_compile(dev_net(skb->dev), opt, skb, NULL);
+ res = __ip_options_compile(dev_net(skb->dev), &parm.opt, skb, NULL);
rcu_read_unlock();
if (res)
return;
if (gateway)
- __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0, opt);
+ __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_NET_ANO, 0, &parm);
else
- __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0, opt);
+ __icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_ANO, 0, &parm);
}
/**
@@ -1811,11 +1809,35 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
return CIPSO_V4_HDR_LEN + ret_val;
}
+static int cipso_v4_get_actual_opt_len(const unsigned char *data, int len)
+{
+ int iter = 0, optlen = 0;
+
+ /* determining the new total option length is tricky because of
+ * the padding necessary, the only thing i can think to do at
+ * this point is walk the options one-by-one, skipping the
+ * padding at the end to determine the actual option size and
+ * from there we can determine the new total option length
+ */
+ while (iter < len) {
+ if (data[iter] == IPOPT_END) {
+ break;
+ } else if (data[iter] == IPOPT_NOP) {
+ iter++;
+ } else {
+ iter += data[iter + 1];
+ optlen = iter;
+ }
+ }
+ return optlen;
+}
+
/**
* cipso_v4_sock_setattr - Add a CIPSO option to a socket
* @sk: the socket
* @doi_def: the CIPSO DOI to use
* @secattr: the specific security attributes of the socket
+ * @sk_locked: true if caller holds the socket lock
*
* Description:
* Set the CIPSO option on the given socket using the DOI definition and
@@ -1827,7 +1849,8 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
*/
int cipso_v4_sock_setattr(struct sock *sk,
const struct cipso_v4_doi *doi_def,
- const struct netlbl_lsm_secattr *secattr)
+ const struct netlbl_lsm_secattr *secattr,
+ bool sk_locked)
{
int ret_val = -EPERM;
unsigned char *buf = NULL;
@@ -1877,9 +1900,8 @@ int cipso_v4_sock_setattr(struct sock *sk,
sk_inet = inet_sk(sk);
- old = rcu_dereference_protected(sk_inet->inet_opt,
- lockdep_sock_is_held(sk));
- if (sk_inet->is_icsk) {
+ old = rcu_dereference_protected(sk_inet->inet_opt, sk_locked);
+ if (inet_test_bit(IS_ICSK, sk)) {
sk_conn = inet_csk(sk);
if (old)
sk_conn->icsk_ext_hdr_len -= old->opt.optlen;
@@ -1953,7 +1975,7 @@ int cipso_v4_req_setattr(struct request_sock *req,
buf = NULL;
req_inet = inet_rsk(req);
- opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt);
+ opt = unrcu_pointer(xchg(&req_inet->ireq_opt, RCU_INITIALIZER(opt)));
if (opt)
kfree_rcu(opt, rcu);
@@ -1986,7 +2008,6 @@ static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr)
u8 cipso_len;
u8 cipso_off;
unsigned char *cipso_ptr;
- int iter;
int optlen_new;
cipso_off = opt->opt.cipso - sizeof(struct iphdr);
@@ -2006,19 +2027,8 @@ static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr)
memmove(cipso_ptr, cipso_ptr + cipso_len,
opt->opt.optlen - cipso_off - cipso_len);
- /* determining the new total option length is tricky because of
- * the padding necessary, the only thing i can think to do at
- * this point is walk the options one-by-one, skipping the
- * padding at the end to determine the actual option size and
- * from there we can determine the new total option length */
- iter = 0;
- optlen_new = 0;
- while (iter < opt->opt.optlen)
- if (opt->opt.__data[iter] != IPOPT_NOP) {
- iter += opt->opt.__data[iter + 1];
- optlen_new = iter;
- } else
- iter++;
+ optlen_new = cipso_v4_get_actual_opt_len(opt->opt.__data,
+ opt->opt.optlen);
hdr_delta = opt->opt.optlen;
opt->opt.optlen = (optlen_new + 3) & ~3;
hdr_delta -= opt->opt.optlen;
@@ -2049,7 +2059,7 @@ void cipso_v4_sock_delattr(struct sock *sk)
sk_inet = inet_sk(sk);
hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt);
- if (sk_inet->is_icsk && hdr_delta > 0) {
+ if (inet_test_bit(IS_ICSK, sk) && hdr_delta > 0) {
struct inet_connection_sock *sk_conn = inet_csk(sk);
sk_conn->icsk_ext_hdr_len -= hdr_delta;
sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
@@ -2220,7 +2230,7 @@ int cipso_v4_skbuff_setattr(struct sk_buff *skb,
memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len);
if (len_delta != 0) {
iph->ihl = 5 + (opt_len >> 2);
- iph->tot_len = htons(skb->len);
+ iph_set_totlen(iph, skb->len);
}
ip_send_check(iph);
@@ -2238,7 +2248,8 @@ int cipso_v4_skbuff_setattr(struct sk_buff *skb,
*/
int cipso_v4_skbuff_delattr(struct sk_buff *skb)
{
- int ret_val;
+ int ret_val, cipso_len, hdr_len_actual, new_hdr_len_actual, new_hdr_len,
+ hdr_len_delta;
struct iphdr *iph;
struct ip_options *opt = &IPCB(skb)->opt;
unsigned char *cipso_ptr;
@@ -2251,16 +2262,37 @@ int cipso_v4_skbuff_delattr(struct sk_buff *skb)
if (ret_val < 0)
return ret_val;
- /* the easiest thing to do is just replace the cipso option with noop
- * options since we don't change the size of the packet, although we
- * still need to recalculate the checksum */
-
iph = ip_hdr(skb);
cipso_ptr = (unsigned char *)iph + opt->cipso;
- memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]);
+ cipso_len = cipso_ptr[1];
+
+ hdr_len_actual = sizeof(struct iphdr) +
+ cipso_v4_get_actual_opt_len((unsigned char *)(iph + 1),
+ opt->optlen);
+ new_hdr_len_actual = hdr_len_actual - cipso_len;
+ new_hdr_len = (new_hdr_len_actual + 3) & ~3;
+ hdr_len_delta = (iph->ihl << 2) - new_hdr_len;
+
+ /* 1. shift any options after CIPSO to the left */
+ memmove(cipso_ptr, cipso_ptr + cipso_len,
+ new_hdr_len_actual - opt->cipso);
+ /* 2. move the whole IP header to its new place */
+ memmove((unsigned char *)iph + hdr_len_delta, iph, new_hdr_len_actual);
+ /* 3. adjust the skb layout */
+ skb_pull(skb, hdr_len_delta);
+ skb_reset_network_header(skb);
+ iph = ip_hdr(skb);
+ /* 4. re-fill new padding with IPOPT_END (may now be longer) */
+ memset((unsigned char *)iph + new_hdr_len_actual, IPOPT_END,
+ new_hdr_len - new_hdr_len_actual);
+
+ opt->optlen -= hdr_len_delta;
opt->cipso = 0;
opt->is_changed = 1;
-
+ if (hdr_len_delta != 0) {
+ iph->ihl = new_hdr_len >> 2;
+ iph_set_totlen(iph, skb->len);
+ }
ip_send_check(iph);
return 0;
generated by cgit (git 2.34.1) at 2025-12-26 08:00:16 +0000