From: Sasha Levin <sashal@kernel•org>
To: linux-kernel@vger•kernel.org, stable@vger•kernel.org
Cc: Antony Antony <antony.antony@secunet•com>,
Thomas Egerer <thomas.egerer@secunet•com>,
Steffen Klassert <steffen.klassert@secunet•com>,
Sasha Levin <sashal@kernel•org>,
davem@davemloft•net, kuba@kernel•org, netdev@vger•kernel.org
Subject: [PATCH AUTOSEL 5.16 176/217] xfrm: rate limit SA mapping change message to user space
Date: Mon, 17 Jan 2022 21:18:59 -0500 [thread overview]
Message-ID: <20220118021940.1942199-176-sashal@kernel.org> (raw)
In-Reply-To: <20220118021940.1942199-1-sashal@kernel.org>
From: Antony Antony <antony.antony@secunet•com>
[ Upstream commit 4e484b3e969b52effd95c17f7a86f39208b2ccf4 ]
Kernel generates mapping change message, XFRM_MSG_MAPPING,
when a source port chage is detected on a input state with UDP
encapsulation set. Kernel generates a message for each IPsec packet
with new source port. For a high speed flow per packet mapping change
message can be excessive, and can overload the user space listener.
Introduce rate limiting for XFRM_MSG_MAPPING message to the user space.
The rate limiting is configurable via netlink, when adding a new SA or
updating it. Use the new attribute XFRMA_MTIMER_THRESH in seconds.
v1->v2 change:
update xfrm_sa_len()
v2->v3 changes:
use u32 insted unsigned long to reduce size of struct xfrm_state
fix xfrm_ompat size Reported-by: kernel test robot <lkp@intel•com>
accept XFRM_MSG_MAPPING only when XFRMA_ENCAP is present
Co-developed-by: Thomas Egerer <thomas.egerer@secunet•com>
Signed-off-by: Thomas Egerer <thomas.egerer@secunet•com>
Signed-off-by: Antony Antony <antony.antony@secunet•com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet•com>
Signed-off-by: Sasha Levin <sashal@kernel•org>
---
include/net/xfrm.h | 5 +++++
include/uapi/linux/xfrm.h | 1 +
net/xfrm/xfrm_compat.c | 6 ++++--
net/xfrm/xfrm_state.c | 23 ++++++++++++++++++++++-
net/xfrm/xfrm_user.c | 18 +++++++++++++++++-
5 files changed, 49 insertions(+), 4 deletions(-)
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 2308210793a01..2589e4c0501bd 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -200,6 +200,11 @@ struct xfrm_state {
struct xfrm_algo_aead *aead;
const char *geniv;
+ /* mapping change rate limiting */
+ __be16 new_mapping_sport;
+ u32 new_mapping; /* seconds */
+ u32 mapping_maxage; /* seconds for input SA */
+
/* Data for encapsulator */
struct xfrm_encap_tmpl *encap;
struct sock __rcu *encap_sk;
diff --git a/include/uapi/linux/xfrm.h b/include/uapi/linux/xfrm.h
index eda0426ec4c2b..4e29d78518902 100644
--- a/include/uapi/linux/xfrm.h
+++ b/include/uapi/linux/xfrm.h
@@ -313,6 +313,7 @@ enum xfrm_attr_type_t {
XFRMA_SET_MARK, /* __u32 */
XFRMA_SET_MARK_MASK, /* __u32 */
XFRMA_IF_ID, /* __u32 */
+ XFRMA_MTIMER_THRESH, /* __u32 in seconds for input SA */
__XFRMA_MAX
#define XFRMA_OUTPUT_MARK XFRMA_SET_MARK /* Compatibility */
diff --git a/net/xfrm/xfrm_compat.c b/net/xfrm/xfrm_compat.c
index 2bf2693901631..a0f62fa02e06e 100644
--- a/net/xfrm/xfrm_compat.c
+++ b/net/xfrm/xfrm_compat.c
@@ -127,6 +127,7 @@ static const struct nla_policy compat_policy[XFRMA_MAX+1] = {
[XFRMA_SET_MARK] = { .type = NLA_U32 },
[XFRMA_SET_MARK_MASK] = { .type = NLA_U32 },
[XFRMA_IF_ID] = { .type = NLA_U32 },
+ [XFRMA_MTIMER_THRESH] = { .type = NLA_U32 },
};
static struct nlmsghdr *xfrm_nlmsg_put_compat(struct sk_buff *skb,
@@ -274,9 +275,10 @@ static int xfrm_xlate64_attr(struct sk_buff *dst, const struct nlattr *src)
case XFRMA_SET_MARK:
case XFRMA_SET_MARK_MASK:
case XFRMA_IF_ID:
+ case XFRMA_MTIMER_THRESH:
return xfrm_nla_cpy(dst, src, nla_len(src));
default:
- BUILD_BUG_ON(XFRMA_MAX != XFRMA_IF_ID);
+ BUILD_BUG_ON(XFRMA_MAX != XFRMA_MTIMER_THRESH);
pr_warn_once("unsupported nla_type %d\n", src->nla_type);
return -EOPNOTSUPP;
}
@@ -431,7 +433,7 @@ static int xfrm_xlate32_attr(void *dst, const struct nlattr *nla,
int err;
if (type > XFRMA_MAX) {
- BUILD_BUG_ON(XFRMA_MAX != XFRMA_IF_ID);
+ BUILD_BUG_ON(XFRMA_MAX != XFRMA_MTIMER_THRESH);
NL_SET_ERR_MSG(extack, "Bad attribute");
return -EOPNOTSUPP;
}
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index a2f4001221d16..78d51399a0f4b 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1593,6 +1593,9 @@ static struct xfrm_state *xfrm_state_clone(struct xfrm_state *orig,
x->km.seq = orig->km.seq;
x->replay = orig->replay;
x->preplay = orig->preplay;
+ x->mapping_maxage = orig->mapping_maxage;
+ x->new_mapping = 0;
+ x->new_mapping_sport = 0;
return x;
@@ -2242,7 +2245,7 @@ int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol)
}
EXPORT_SYMBOL(km_query);
-int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport)
+static int __km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport)
{
int err = -EINVAL;
struct xfrm_mgr *km;
@@ -2257,6 +2260,24 @@ int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport)
rcu_read_unlock();
return err;
}
+
+int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport)
+{
+ int ret = 0;
+
+ if (x->mapping_maxage) {
+ if ((jiffies / HZ - x->new_mapping) > x->mapping_maxage ||
+ x->new_mapping_sport != sport) {
+ x->new_mapping_sport = sport;
+ x->new_mapping = jiffies / HZ;
+ ret = __km_new_mapping(x, ipaddr, sport);
+ }
+ } else {
+ ret = __km_new_mapping(x, ipaddr, sport);
+ }
+
+ return ret;
+}
EXPORT_SYMBOL(km_new_mapping);
void km_policy_expired(struct xfrm_policy *pol, int dir, int hard, u32 portid)
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 7c36cc1f3d79c..130240680655f 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -282,6 +282,10 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
err = 0;
+ if (attrs[XFRMA_MTIMER_THRESH])
+ if (!attrs[XFRMA_ENCAP])
+ err = -EINVAL;
+
out:
return err;
}
@@ -521,6 +525,7 @@ static void xfrm_update_ae_params(struct xfrm_state *x, struct nlattr **attrs,
struct nlattr *lt = attrs[XFRMA_LTIME_VAL];
struct nlattr *et = attrs[XFRMA_ETIMER_THRESH];
struct nlattr *rt = attrs[XFRMA_REPLAY_THRESH];
+ struct nlattr *mt = attrs[XFRMA_MTIMER_THRESH];
if (re) {
struct xfrm_replay_state_esn *replay_esn;
@@ -552,6 +557,9 @@ static void xfrm_update_ae_params(struct xfrm_state *x, struct nlattr **attrs,
if (rt)
x->replay_maxdiff = nla_get_u32(rt);
+
+ if (mt)
+ x->mapping_maxage = nla_get_u32(mt);
}
static void xfrm_smark_init(struct nlattr **attrs, struct xfrm_mark *m)
@@ -1024,8 +1032,13 @@ static int copy_to_user_state_extra(struct xfrm_state *x,
if (ret)
goto out;
}
- if (x->security)
+ if (x->security) {
ret = copy_sec_ctx(x->security, skb);
+ if (ret)
+ goto out;
+ }
+ if (x->mapping_maxage)
+ ret = nla_put_u32(skb, XFRMA_MTIMER_THRESH, x->mapping_maxage);
out:
return ret;
}
@@ -3069,6 +3082,9 @@ static inline unsigned int xfrm_sa_len(struct xfrm_state *x)
/* Must count x->lastused as it may become non-zero behind our back. */
l += nla_total_size_64bit(sizeof(u64));
+ if (x->mapping_maxage)
+ l += nla_total_size(sizeof(x->mapping_maxage));
+
return l;
}
--
2.34.1
next prev parent reply other threads:[~2022-01-18 2:42 UTC|newest]
Thread overview: 95+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-18 2:16 [PATCH AUTOSEL 5.16 001/217] Bluetooth: hci_sock: purge socket queues in the destruct() callback Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 002/217] Bluetooth: Fix debugfs entry leak in hci_register_dev() Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 003/217] Bluetooth: Fix memory leak of hci device Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 005/217] Bluetooth: Fix removing adv when processing cmd complete Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 008/217] libbpf: Detect corrupted ELF symbols section Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 009/217] libbpf: Improve sanity checking during BTF fix up Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 010/217] libbpf: Validate that .BTF and .BTF.ext sections contain data Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 012/217] selftests/bpf: Fix memory leaks in btf_type_c_dump() helper Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 013/217] selftests/bpf: Destroy XDP link correctly Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 014/217] selftests/bpf: Fix bpf_object leak in skb_ctx selftest Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 015/217] ar5523: Fix null-ptr-deref with unexpected WDCMSG_TARGET_START reply Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 024/217] ath11k: enable IEEE80211_VHT_EXT_NSS_BW_CAPABLE if NSS ratio enabled Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 025/217] batman-adv: allow netlink usage in unprivileged containers Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 026/217] bpf: Change value of MAX_TAIL_CALL_CNT from 32 to 33 Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 028/217] ath11k: Fix crash caused by uninitialized TX ring Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 034/217] amd: lance: use eth_hw_addr_set() Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 035/217] amd: ni65: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 036/217] amd: a2065/ariadne: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 037/217] amd: hplance: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 038/217] amd: atarilance: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 039/217] amd: mvme147: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 040/217] 8390: smc-ultra: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 041/217] 8390: hydra: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 042/217] 8390: mac8390: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 043/217] 8390: wd: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 044/217] smc9194: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 045/217] lasi_82594: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 046/217] apple: macmace: " Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 047/217] cirrus: mac89x0: " Sasha Levin
2022-01-18 16:56 ` Jakub Kicinski
2022-01-22 18:51 ` Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 051/217] libbpf: Accommodate DWARF/compiler bug with duplicated structs Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 052/217] ethernet: renesas: Use div64_ul instead of do_div Sasha Levin
2022-01-18 2:16 ` [PATCH AUTOSEL 5.16 053/217] 82596: use eth_hw_addr_set() Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 059/217] ath11k: Fix mon status ring rx tlv processing Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 063/217] mlxsw: pci: Add shutdown method in PCI driver Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 074/217] rtw89: fix potentially access out of range of RF register array Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 075/217] rtw88: add quirk to disable pci caps on HP 250 G7 Notebook PC Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 076/217] mwifiex: Fix skb_over_panic in mwifiex_usb_recv() Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 077/217] rsi: Fix use-after-free in rsi_rx_done_handler() Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 078/217] rsi: Fix out-of-bounds read in rsi_read_pkt() Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 079/217] ath11k: Avoid NULL ptr access during mgmt tx cleanup Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 104/217] iwlwifi: mvm: synchronize with FW after multicast commands Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 105/217] iwlwifi: mvm: avoid clearing a just saved session protection id Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 106/217] iwlwifi: acpi: fix wgds rev 3 size Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 108/217] net: dsa: ocelot: felix: Remove requirement for PCS in felix devices Sasha Levin
2022-01-18 12:23 ` Vladimir Oltean
2022-01-22 19:02 ` Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 109/217] ath11k: avoid deadlock by change ieee80211_queue_work for regd_update_work Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 110/217] ath10k: Fix tx hanging Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 111/217] rtw89: don't kick off TX DMA if failed to write skb Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 112/217] net-sysfs: update the queue counts in the unregistration path Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 113/217] ath10k: drop beacon and probe response which leak from other channel Sasha Levin
2022-01-18 2:17 ` [PATCH AUTOSEL 5.16 114/217] net: phy: prefer 1000baseT over 1000baseKX Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 118/217] net: Enable neighbor sysctls that is save for userns root Sasha Levin
2022-01-18 16:59 ` Jakub Kicinski
2022-01-19 3:46 ` David Ahern
2022-01-22 19:13 ` Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 120/217] ath11k: Avoid false DEADLOCK warning reported by lockdep Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 127/217] net: bonding: debug: avoid printing debug logs when bond is not notifying peers Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 129/217] bpf: Do not WARN in bpf_warn_invalid_xdp_action() Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 152/217] mt76: mt7615: fix possible deadlock while mt7615_register_ext_phy() Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 153/217] mt76: mt7915: fix SMPS operation fail Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 154/217] mt76: connac: fix a theoretical NULL pointer dereference in mt76_connac_get_phy_mode Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 155/217] mt76: do not pass the received frame with decryption error Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 156/217] mt76: mt7615: improve wmm index allocation Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 157/217] mt76: mt7921: fix network buffer leak by txs missing Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 158/217] ath9k_htc: fix NULL pointer dereference at ath9k_htc_rxep() Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 159/217] ath9k_htc: fix NULL pointer dereference at ath9k_htc_tx_get_packet() Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 160/217] ath9k: Fix out-of-bound memcpy in ath9k_hif_usb_rx_stream Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 161/217] rtw88: 8822c: update rx settings to prevent potential hw deadlock Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 163/217] iwlwifi: recognize missing PNVM data and then log filename Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 164/217] iwlwifi: fix leaks/bad data after failed firmware load Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 165/217] iwlwifi: remove module loading failure message Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 166/217] iwlwifi: mvm: Fix calculation of frame length Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 167/217] iwlwifi: mvm: fix AUX ROC removal Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 168/217] iwlwifi: pcie: make sure prph_info is set when treating wakeup IRQ Sasha Levin
2022-01-18 2:18 ` [PATCH AUTOSEL 5.16 172/217] ath11k: Fix napi related hang Sasha Levin
2022-01-18 2:18 ` Sasha Levin [this message]
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 191/217] net/mlx5: DR, Fix error flow in creating matcher Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 194/217] net: mdio: Demote probed message to debug print Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 195/217] mac80211: allow non-standard VHT MCS-10/11 Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 198/217] can: do not increase rx statistics when generating a CAN rx error message frame Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 199/217] bpf/selftests: Fix namespace mount setup in tc_redirect Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 200/217] mlxsw: pci: Avoid flow control for EMAD packets Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 201/217] net: phy: marvell: configure RGMII delays for 88E1118 Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 202/217] net: gemini: allow any RGMII interface mode Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 203/217] net: dsa: hold rtnl_mutex when calling dsa_master_{setup,teardown} Sasha Levin
2022-01-18 12:13 ` Vladimir Oltean
2022-01-22 19:17 ` Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 209/217] net/mlx5: Update log_max_qp value to FW max capability Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 210/217] net/mlx5e: Unblock setting vid 0 for VF in case PF isn't eswitch manager Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 213/217] can: flexcan: allow to change quirks at runtime Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 214/217] can: flexcan: rename RX modes Sasha Levin
2022-01-18 2:19 ` [PATCH AUTOSEL 5.16 215/217] can: flexcan: add more quirks to describe RX path capabilities Sasha Levin
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