Commit 552cc230 authored by Jinliang Zheng's avatar Jinliang Zheng Committed by Jakub Kicinski
Browse files

macsec: use rcu_work to defer TX SA crypto cleanup out of softirq 



free_txsa() is an RCU callback running in softirq context, but calls
crypto_free_aead() which can invoke vunmap() internally on hardware
crypto drivers (e.g. hisi_sec2), triggering a kernel crash.

Use rcu_work to defer the cleanup to a workqueue, for the same reasons
as the analogous fix to free_rxsa() in the previous patch.

Fixes: c09440f7 ("macsec: introduce IEEE 802.1AE driver")
Signed-off-by: default avatarJinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: default avatarSabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20260511153102.2640368-4-alexjlzheng@tencent.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 6624bba4

drivers/net/macsec.c

+5 −3
Original line number Diff line number Diff line
@@ -205,9 +205,10 @@ static struct macsec_tx_sa *macsec_txsa_get(struct macsec_tx_sa __rcu *ptr) 
	return sa;

}



static void free_txsa(struct rcu_head *head)

static void free_txsa_work(struct work_struct *work)

{

	struct macsec_tx_sa *sa = container_of(head, struct macsec_tx_sa, rcu);

	struct macsec_tx_sa *sa =

		container_of(to_rcu_work(work), struct macsec_tx_sa, destroy_work);



	crypto_free_aead(sa->key.tfm);

	free_percpu(sa->stats);
@@ -217,7 +218,7 @@ static void free_txsa(struct rcu_head *head) 
static void macsec_txsa_put(struct macsec_tx_sa *sa)

{

	if (refcount_dec_and_test(&sa->refcnt))

		call_rcu(&sa->rcu, free_txsa);

		queue_rcu_work(macsec_wq, &sa->destroy_work);

}



static struct macsec_cb *macsec_skb_cb(struct sk_buff *skb)
@@ -1510,6 +1511,7 @@ static int init_tx_sa(struct macsec_tx_sa *tx_sa, char *sak, int key_len, 
	tx_sa->active = false;

	refcount_set(&tx_sa->refcnt, 1);

	spin_lock_init(&tx_sa->lock);

	INIT_RCU_WORK(&tx_sa->destroy_work, free_txsa_work);



	return 0;

}

include/net/macsec.h

+2 −1
Original line number Diff line number Diff line
@@ -176,6 +176,7 @@ struct macsec_rx_sc { 
 * @key: key structure

 * @ssci: short secure channel identifier

 * @stats: per-SA stats

 * @destroy_work: deferred work to free the SA in process context after RCU grace period

 */

struct macsec_tx_sa {

	struct macsec_key key;
@@ -188,7 +189,7 @@ struct macsec_tx_sa { 
	refcount_t refcnt;

	bool active;

	struct macsec_tx_sa_stats __percpu *stats;

	struct rcu_head rcu;

	struct rcu_work destroy_work;

};



/**