| Message ID | 20220726201600.1715505-5-dima@arista.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net/crypto: Introduce crypto_pool | expand |
Hi Dmitry,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on 058affafc65a74cf54499fb578b66ad0b18f939b]
url: https://github.com/intel-lab-lkp/linux/commits/Dmitry-Safonov/net-crypto-Introduce-crypto_pool/20220727-041830
base: 058affafc65a74cf54499fb578b66ad0b18f939b
config: i386-randconfig-a005 (https://download.01.org/0day-ci/archive/20220814/202208142357.bDGLpecB-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
# https://github.com/intel-lab-lkp/linux/commit/a4ee3ecdaada036ed6747ed86eaf7270d3f27bab
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Dmitry-Safonov/net-crypto-Introduce-crypto_pool/20220727-041830
git checkout a4ee3ecdaada036ed6747ed86eaf7270d3f27bab
# save the config file
mkdir build_dir && cp config build_dir/.config
make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash net/ipv4/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> net/ipv4/tcp_ipv4.c:1174:5: warning: no previous prototype for '__tcp_md5_do_add' [-Wmissing-prototypes]
1174 | int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
| ^~~~~~~~~~~~~~~~
vim +/__tcp_md5_do_add +1174 net/ipv4/tcp_ipv4.c
1172
1173 /* This can be called on a newly created socket, from other files */
> 1174 int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
1175 int family, u8 prefixlen, int l3index, u8 flags,
1176 const u8 *newkey, u8 newkeylen, gfp_t gfp)
1177 {
1178 /* Add Key to the list */
1179 struct tcp_md5sig_key *key;
1180 struct tcp_sock *tp = tcp_sk(sk);
1181 struct tcp_md5sig_info *md5sig;
1182
1183 key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index, flags);
1184 if (key) {
1185 /* Pre-existing entry - just update that one.
1186 * Note that the key might be used concurrently.
1187 * data_race() is telling kcsan that we do not care of
1188 * key mismatches, since changing MD5 key on live flows
1189 * can lead to packet drops.
1190 */
1191 data_race(memcpy(key->key, newkey, newkeylen));
1192
1193 /* Pairs with READ_ONCE() in tcp_md5_hash_key().
1194 * Also note that a reader could catch new key->keylen value
1195 * but old key->key[], this is the reason we use __GFP_ZERO
1196 * at sock_kmalloc() time below these lines.
1197 */
1198 WRITE_ONCE(key->keylen, newkeylen);
1199
1200 return 0;
1201 }
1202
1203 md5sig = rcu_dereference_protected(tp->md5sig_info,
1204 lockdep_sock_is_held(sk));
1205
1206 key = sock_kmalloc(sk, sizeof(*key), gfp | __GFP_ZERO);
1207 if (!key)
1208 return -ENOMEM;
1209 if (!tcp_alloc_md5sig_pool()) {
1210 sock_kfree_s(sk, key, sizeof(*key));
1211 return -ENOMEM;
1212 }
1213
1214 memcpy(key->key, newkey, newkeylen);
1215 key->keylen = newkeylen;
1216 key->family = family;
1217 key->prefixlen = prefixlen;
1218 key->l3index = l3index;
1219 key->flags = flags;
1220 memcpy(&key->addr, addr,
1221 (IS_ENABLED(CONFIG_IPV6) && family == AF_INET6) ? sizeof(struct in6_addr) :
1222 sizeof(struct in_addr));
1223 hlist_add_head_rcu(&key->node, &md5sig->head);
1224 return 0;
1225 }
1226
Hi Dmitry,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on 058affafc65a74cf54499fb578b66ad0b18f939b]
url: https://github.com/intel-lab-lkp/linux/commits/Dmitry-Safonov/net-crypto-Introduce-crypto_pool/20220727-041830
base: 058affafc65a74cf54499fb578b66ad0b18f939b
config: x86_64-defconfig (https://download.01.org/0day-ci/archive/20220814/202208142332.WUqM9sfv-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
# https://github.com/intel-lab-lkp/linux/commit/a4ee3ecdaada036ed6747ed86eaf7270d3f27bab
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Dmitry-Safonov/net-crypto-Introduce-crypto_pool/20220727-041830
git checkout a4ee3ecdaada036ed6747ed86eaf7270d3f27bab
# save the config file
mkdir build_dir && cp config build_dir/.config
make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash net/ipv4/
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> net/ipv4/tcp_ipv4.c:1174:5: warning: no previous prototype for '__tcp_md5_do_add' [-Wmissing-prototypes]
1174 | int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
| ^~~~~~~~~~~~~~~~
vim +/__tcp_md5_do_add +1174 net/ipv4/tcp_ipv4.c
1172
1173 /* This can be called on a newly created socket, from other files */
> 1174 int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
1175 int family, u8 prefixlen, int l3index, u8 flags,
1176 const u8 *newkey, u8 newkeylen, gfp_t gfp)
1177 {
1178 /* Add Key to the list */
1179 struct tcp_md5sig_key *key;
1180 struct tcp_sock *tp = tcp_sk(sk);
1181 struct tcp_md5sig_info *md5sig;
1182
1183 key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index, flags);
1184 if (key) {
1185 /* Pre-existing entry - just update that one.
1186 * Note that the key might be used concurrently.
1187 * data_race() is telling kcsan that we do not care of
1188 * key mismatches, since changing MD5 key on live flows
1189 * can lead to packet drops.
1190 */
1191 data_race(memcpy(key->key, newkey, newkeylen));
1192
1193 /* Pairs with READ_ONCE() in tcp_md5_hash_key().
1194 * Also note that a reader could catch new key->keylen value
1195 * but old key->key[], this is the reason we use __GFP_ZERO
1196 * at sock_kmalloc() time below these lines.
1197 */
1198 WRITE_ONCE(key->keylen, newkeylen);
1199
1200 return 0;
1201 }
1202
1203 md5sig = rcu_dereference_protected(tp->md5sig_info,
1204 lockdep_sock_is_held(sk));
1205
1206 key = sock_kmalloc(sk, sizeof(*key), gfp | __GFP_ZERO);
1207 if (!key)
1208 return -ENOMEM;
1209 if (!tcp_alloc_md5sig_pool()) {
1210 sock_kfree_s(sk, key, sizeof(*key));
1211 return -ENOMEM;
1212 }
1213
1214 memcpy(key->key, newkey, newkeylen);
1215 key->keylen = newkeylen;
1216 key->family = family;
1217 key->prefixlen = prefixlen;
1218 key->l3index = l3index;
1219 key->flags = flags;
1220 memcpy(&key->addr, addr,
1221 (IS_ENABLED(CONFIG_IPV6) && family == AF_INET6) ? sizeof(struct in6_addr) :
1222 sizeof(struct in_addr));
1223 hlist_add_head_rcu(&key->node, &md5sig->head);
1224 return 0;
1225 }
1226
diff --git a/include/net/tcp.h b/include/net/tcp.h index f366626cbbba..aa735f963723 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1663,7 +1663,11 @@ int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, const struct sock *sk, const struct sk_buff *skb); int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags, - const u8 *newkey, u8 newkeylen, gfp_t gfp); + const u8 *newkey, u8 newkeylen); +int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, + struct tcp_md5sig_key *key); + int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags); struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, @@ -1671,7 +1675,7 @@ struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, #ifdef CONFIG_TCP_MD5SIG #include <linux/jump_label.h> -extern struct static_key_false tcp_md5_needed; +extern struct static_key_false_deferred tcp_md5_needed; struct tcp_md5sig_key *__tcp_md5_do_lookup(const struct sock *sk, int l3index, const union tcp_md5_addr *addr, int family); @@ -1679,7 +1683,7 @@ static inline struct tcp_md5sig_key * tcp_md5_do_lookup(const struct sock *sk, int l3index, const union tcp_md5_addr *addr, int family) { - if (!static_branch_unlikely(&tcp_md5_needed)) + if (!static_branch_unlikely(&tcp_md5_needed.key)) return NULL; return __tcp_md5_do_lookup(sk, l3index, addr, family); } diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 635c6782cdbb..300056008e90 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4404,11 +4404,8 @@ bool tcp_alloc_md5sig_pool(void) if (unlikely(!tcp_md5sig_pool_populated)) { mutex_lock(&tcp_md5sig_mutex); - if (!tcp_md5sig_pool_populated) { + if (!tcp_md5sig_pool_populated) __tcp_alloc_md5sig_pool(); - if (tcp_md5sig_pool_populated) - static_branch_inc(&tcp_md5_needed); - } mutex_unlock(&tcp_md5sig_mutex); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 55e4092209a5..5b0caaea5029 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1044,7 +1044,7 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req) * We need to maintain these in the sk structure. */ -DEFINE_STATIC_KEY_FALSE(tcp_md5_needed); +DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_md5_needed, HZ); EXPORT_SYMBOL(tcp_md5_needed); static bool better_md5_match(struct tcp_md5sig_key *old, struct tcp_md5sig_key *new) @@ -1171,9 +1171,9 @@ static int tcp_md5sig_info_add(struct sock *sk, gfp_t gfp) } /* This can be called on a newly created socket, from other files */ -int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, - int family, u8 prefixlen, int l3index, u8 flags, - const u8 *newkey, u8 newkeylen, gfp_t gfp) +int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, u8 flags, + const u8 *newkey, u8 newkeylen, gfp_t gfp) { /* Add Key to the list */ struct tcp_md5sig_key *key; @@ -1200,9 +1200,6 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, return 0; } - if (tcp_md5sig_info_add(sk, gfp)) - return -ENOMEM; - md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); @@ -1226,8 +1223,36 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, hlist_add_head_rcu(&key->node, &md5sig->head); return 0; } + +int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, u8 flags, + const u8 *newkey, u8 newkeylen) +{ + if (tcp_md5sig_info_add(sk, GFP_KERNEL)) + return -ENOMEM; + + static_branch_inc(&tcp_md5_needed.key); + + return __tcp_md5_do_add(sk, addr, family, prefixlen, l3index, flags, + newkey, newkeylen, GFP_KERNEL); +} EXPORT_SYMBOL(tcp_md5_do_add); +int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, + struct tcp_md5sig_key *key) +{ + if (tcp_md5sig_info_add(sk, sk_gfp_mask(sk, GFP_ATOMIC))) + return -ENOMEM; + + atomic_inc(&tcp_md5_needed.key.key.enabled); + + return __tcp_md5_do_add(sk, addr, family, prefixlen, l3index, + key->flags, key->key, key->keylen, + sk_gfp_mask(sk, GFP_ATOMIC)); +} +EXPORT_SYMBOL(tcp_md5_key_copy); + int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags) { @@ -1314,7 +1339,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname, return -EINVAL; return tcp_md5_do_add(sk, addr, AF_INET, prefixlen, l3index, flags, - cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); + cmd.tcpm_key, cmd.tcpm_keylen); } static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp, @@ -1571,8 +1596,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, * memory, then we end up not copying the key * across. Shucks. */ - tcp_md5_do_add(newsk, addr, AF_INET, 32, l3index, key->flags, - key->key, key->keylen, GFP_ATOMIC); + tcp_md5_key_copy(newsk, addr, AF_INET, 32, l3index, key); sk_gso_disable(newsk); } #endif @@ -2260,6 +2284,7 @@ void tcp_v4_destroy_sock(struct sock *sk) tcp_clear_md5_list(sk); kfree_rcu(rcu_dereference_protected(tp->md5sig_info, 1), rcu); tp->md5sig_info = NULL; + static_branch_slow_dec_deferred(&tcp_md5_needed); } #endif diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index cb95d88497ae..5d475a45a478 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -291,13 +291,14 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) */ do { tcptw->tw_md5_key = NULL; - if (static_branch_unlikely(&tcp_md5_needed)) { + if (static_branch_unlikely(&tcp_md5_needed.key)) { struct tcp_md5sig_key *key; key = tp->af_specific->md5_lookup(sk, sk); if (key) { tcptw->tw_md5_key = kmemdup(key, sizeof(*key), GFP_ATOMIC); BUG_ON(tcptw->tw_md5_key && !tcp_alloc_md5sig_pool()); + atomic_inc(&tcp_md5_needed.key.key.enabled); } } } while (0); @@ -337,11 +338,13 @@ EXPORT_SYMBOL(tcp_time_wait); void tcp_twsk_destructor(struct sock *sk) { #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed)) { + if (static_branch_unlikely(&tcp_md5_needed.key)) { struct tcp_timewait_sock *twsk = tcp_twsk(sk); - if (twsk->tw_md5_key) + if (twsk->tw_md5_key) { kfree_rcu(twsk->tw_md5_key, rcu); + static_branch_slow_dec_deferred(&tcp_md5_needed); + } } #endif } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 78b654ff421b..9e12845a8758 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -766,7 +766,7 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed) && + if (static_branch_unlikely(&tcp_md5_needed.key) && rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { @@ -922,7 +922,7 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed) && + if (static_branch_unlikely(&tcp_md5_needed.key) && rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index e54eee80ce5f..cb891a71db0d 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -658,12 +658,11 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname, if (ipv6_addr_v4mapped(&sin6->sin6_addr)) return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], AF_INET, prefixlen, l3index, flags, - cmd.tcpm_key, cmd.tcpm_keylen, - GFP_KERNEL); + cmd.tcpm_key, cmd.tcpm_keylen); return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, AF_INET6, prefixlen, l3index, flags, - cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); + cmd.tcpm_key, cmd.tcpm_keylen); } static int tcp_v6_md5_hash_headers(struct tcp_md5sig_pool *hp, @@ -1359,9 +1358,8 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * * memory, then we end up not copying the key * across. Shucks. */ - tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, - AF_INET6, 128, l3index, key->flags, key->key, key->keylen, - sk_gfp_mask(sk, GFP_ATOMIC)); + tcp_md5_key_copy(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, + AF_INET6, 128, l3index, key); } #endif
To do that, separate two scenarios: - where it's the first MD5 key on the system, which means that enabling of the static key may need to sleep; - copying of an existing key from a listening socket to the request socket upon receiving a signed TCP segment, where static key was already enabled (when the key was added to the listening socket). Now the life-time of the static branch for TCP-MD5 is until: - last tcp_md5sig_info is destroyed - last socket in time-wait state with MD5 key is closed. Which means that after all sockets with TCP-MD5 keys are gone, the system gets back the performance of disabled md5-key static branch. Signed-off-by: Dmitry Safonov <dima@arista.com> --- include/net/tcp.h | 10 ++++++--- net/ipv4/tcp.c | 5 +---- net/ipv4/tcp_ipv4.c | 45 +++++++++++++++++++++++++++++++--------- net/ipv4/tcp_minisocks.c | 9 +++++--- net/ipv4/tcp_output.c | 4 ++-- net/ipv6/tcp_ipv6.c | 10 ++++----- 6 files changed, 55 insertions(+), 28 deletions(-)