From c3b7d0bd7ac2c501d4806db71ddd383c184968e8 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Fri, 22 Apr 2016 11:28:04 +0200 Subject: [PATCH] macsec: fix rx_sa refcounting with decrypt callback The decrypt callback macsec_decrypt_done needs a reference on the rx_sa and releases it before returning, but macsec_handle_frame already put that reference after macsec_decrypt returned NULL. Set rx_sa to NULL when the decrypt callback runs so that macsec_handle_frame knows it must not release the reference. Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver") Signed-off-by: Sabrina Dubroca Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- drivers/net/macsec.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 2a2136b..1fd2b14 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -880,12 +880,12 @@ static struct sk_buff *macsec_decrypt(struct sk_buff *skb, macsec_skb_cb(skb)->valid = false; skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) - return NULL; + return ERR_PTR(-ENOMEM); req = aead_request_alloc(rx_sa->key.tfm, GFP_ATOMIC); if (!req) { kfree_skb(skb); - return NULL; + return ERR_PTR(-ENOMEM); } hdr = (struct macsec_eth_header *)skb->data; @@ -905,7 +905,7 @@ static struct sk_buff *macsec_decrypt(struct sk_buff *skb, skb = skb_unshare(skb, GFP_ATOMIC); if (!skb) { aead_request_free(req); - return NULL; + return ERR_PTR(-ENOMEM); } } else { /* integrity only: all headers + data authenticated */ @@ -921,14 +921,14 @@ static struct sk_buff *macsec_decrypt(struct sk_buff *skb, dev_hold(dev); ret = crypto_aead_decrypt(req); if (ret == -EINPROGRESS) { - return NULL; + return ERR_PTR(ret); } else if (ret != 0) { /* decryption/authentication failed * 10.6 if validateFrames is disabled, deliver anyway */ if (ret != -EBADMSG) { kfree_skb(skb); - skb = NULL; + skb = ERR_PTR(ret); } } else { macsec_skb_cb(skb)->valid = true; @@ -1146,8 +1146,10 @@ static rx_handler_result_t macsec_handle_frame(struct sk_buff **pskb) secy->validate_frames != MACSEC_VALIDATE_DISABLED) skb = macsec_decrypt(skb, dev, rx_sa, sci, secy); - if (!skb) { - macsec_rxsa_put(rx_sa); + if (IS_ERR(skb)) { + /* the decrypt callback needs the reference */ + if (PTR_ERR(skb) != -EINPROGRESS) + macsec_rxsa_put(rx_sa); rcu_read_unlock(); *pskb = NULL; return RX_HANDLER_CONSUMED; -- 2.7.4