From 568f194e8bd16c353ad50f9ab95d98b20578a39d Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 28 Mar 2014 18:58:23 +0100 Subject: [PATCH] net: ppp: use sk_unattached_filter api For the ppp driver, there are currently two open-coded BPF filters in use, that is, pass_filter and active_filter. Migrate both to make proper use of sk_unattached_filter_{create,destroy} API so that the actual BPF code is decoupled from direct access, and filters can be jited as a side-effect by the internal filter compiler. Joint work with Alexei Starovoitov. Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Cc: Paul Mackerras Cc: linux-ppp@vger.kernel.org Signed-off-by: David S. Miller --- drivers/net/ppp/ppp_generic.c | 60 ++++++++++++++++++++++++----------- 1 file changed, 41 insertions(+), 19 deletions(-) diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 72ff14b811c6..e3923ebb693f 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -143,9 +143,8 @@ struct ppp { struct sk_buff_head mrq; /* MP: receive reconstruction queue */ #endif /* CONFIG_PPP_MULTILINK */ #ifdef CONFIG_PPP_FILTER - struct sock_filter *pass_filter; /* filter for packets to pass */ - struct sock_filter *active_filter;/* filter for pkts to reset idle */ - unsigned pass_len, active_len; + struct sk_filter *pass_filter; /* filter for packets to pass */ + struct sk_filter *active_filter;/* filter for pkts to reset idle */ #endif /* CONFIG_PPP_FILTER */ struct net *ppp_net; /* the net we belong to */ struct ppp_link_stats stats64; /* 64 bit network stats */ @@ -755,28 +754,42 @@ static long ppp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case PPPIOCSPASS: { struct sock_filter *code; + err = get_filter(argp, &code); if (err >= 0) { + struct sock_fprog fprog = { + .len = err, + .filter = code, + }; + ppp_lock(ppp); - kfree(ppp->pass_filter); - ppp->pass_filter = code; - ppp->pass_len = err; + if (ppp->pass_filter) + sk_unattached_filter_destroy(ppp->pass_filter); + err = sk_unattached_filter_create(&ppp->pass_filter, + &fprog); + kfree(code); ppp_unlock(ppp); - err = 0; } break; } case PPPIOCSACTIVE: { struct sock_filter *code; + err = get_filter(argp, &code); if (err >= 0) { + struct sock_fprog fprog = { + .len = err, + .filter = code, + }; + ppp_lock(ppp); - kfree(ppp->active_filter); - ppp->active_filter = code; - ppp->active_len = err; + if (ppp->active_filter) + sk_unattached_filter_destroy(ppp->active_filter); + err = sk_unattached_filter_create(&ppp->active_filter, + &fprog); + kfree(code); ppp_unlock(ppp); - err = 0; } break; } @@ -1184,7 +1197,7 @@ ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) a four-byte PPP header on each packet */ *skb_push(skb, 2) = 1; if (ppp->pass_filter && - sk_run_filter(skb, ppp->pass_filter) == 0) { + SK_RUN_FILTER(ppp->pass_filter, skb) == 0) { if (ppp->debug & 1) netdev_printk(KERN_DEBUG, ppp->dev, "PPP: outbound frame " @@ -1194,7 +1207,7 @@ ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) } /* if this packet passes the active filter, record the time */ if (!(ppp->active_filter && - sk_run_filter(skb, ppp->active_filter) == 0)) + SK_RUN_FILTER(ppp->active_filter, skb) == 0)) ppp->last_xmit = jiffies; skb_pull(skb, 2); #else @@ -1818,7 +1831,7 @@ ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) *skb_push(skb, 2) = 0; if (ppp->pass_filter && - sk_run_filter(skb, ppp->pass_filter) == 0) { + SK_RUN_FILTER(ppp->pass_filter, skb) == 0) { if (ppp->debug & 1) netdev_printk(KERN_DEBUG, ppp->dev, "PPP: inbound frame " @@ -1827,7 +1840,7 @@ ppp_receive_nonmp_frame(struct ppp *ppp, struct sk_buff *skb) return; } if (!(ppp->active_filter && - sk_run_filter(skb, ppp->active_filter) == 0)) + SK_RUN_FILTER(ppp->active_filter, skb) == 0)) ppp->last_recv = jiffies; __skb_pull(skb, 2); } else @@ -2672,6 +2685,10 @@ ppp_create_interface(struct net *net, int unit, int *retp) ppp->minseq = -1; skb_queue_head_init(&ppp->mrq); #endif /* CONFIG_PPP_MULTILINK */ +#ifdef CONFIG_PPP_FILTER + ppp->pass_filter = NULL; + ppp->active_filter = NULL; +#endif /* CONFIG_PPP_FILTER */ /* * drum roll: don't forget to set @@ -2802,10 +2819,15 @@ static void ppp_destroy_interface(struct ppp *ppp) skb_queue_purge(&ppp->mrq); #endif /* CONFIG_PPP_MULTILINK */ #ifdef CONFIG_PPP_FILTER - kfree(ppp->pass_filter); - ppp->pass_filter = NULL; - kfree(ppp->active_filter); - ppp->active_filter = NULL; + if (ppp->pass_filter) { + sk_unattached_filter_destroy(ppp->pass_filter); + ppp->pass_filter = NULL; + } + + if (ppp->active_filter) { + sk_unattached_filter_destroy(ppp->active_filter); + ppp->active_filter = NULL; + } #endif /* CONFIG_PPP_FILTER */ kfree_skb(ppp->xmit_pending); -- 2.30.2