diff options
| -rw-r--r-- | include/linux/netdevice.h | 2 | ||||
| -rw-r--r-- | net/core/dev.c | 6 | ||||
| -rw-r--r-- | net/core/filter.c | 78 |
3 files changed, 53 insertions, 33 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4f234b102892..94eef356a65f 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2389,6 +2389,8 @@ void synchronize_net(void); int init_dummy_netdev(struct net_device *dev); DECLARE_PER_CPU(int, xmit_recursion); +#define XMIT_RECURSION_LIMIT 10 + static inline int dev_recursion_level(void) { return this_cpu_read(xmit_recursion); diff --git a/net/core/dev.c b/net/core/dev.c index c43c9d2a88cf..b14835757141 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3144,8 +3144,6 @@ static void skb_update_prio(struct sk_buff *skb) DEFINE_PER_CPU(int, xmit_recursion); EXPORT_SYMBOL(xmit_recursion); -#define RECURSION_LIMIT 10 - /** * dev_loopback_xmit - loop back @skb * @net: network namespace this loopback is happening in @@ -3388,8 +3386,8 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv) int cpu = smp_processor_id(); /* ok because BHs are off */ if (txq->xmit_lock_owner != cpu) { - - if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT) + if (unlikely(__this_cpu_read(xmit_recursion) > + XMIT_RECURSION_LIMIT)) goto recursion_alert; skb = validate_xmit_skb(skb, dev); diff --git a/net/core/filter.c b/net/core/filter.c index 68adb5f52110..df6860c85d72 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -748,6 +748,17 @@ static bool chk_code_allowed(u16 code_to_probe) return codes[code_to_probe]; } +static bool bpf_check_basics_ok(const struct sock_filter *filter, + unsigned int flen) +{ + if (filter == NULL) + return false; + if (flen == 0 || flen > BPF_MAXINSNS) + return false; + + return true; +} + /** * bpf_check_classic - verify socket filter code * @filter: filter to verify @@ -768,9 +779,6 @@ static int bpf_check_classic(const struct sock_filter *filter, bool anc_found; int pc; - if (flen == 0 || flen > BPF_MAXINSNS) - return -EINVAL; - /* Check the filter code now */ for (pc = 0; pc < flen; pc++) { const struct sock_filter *ftest = &filter[pc]; @@ -1065,7 +1073,7 @@ int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog) struct bpf_prog *fp; /* Make sure new filter is there and in the right amounts. */ - if (fprog->filter == NULL) + if (!bpf_check_basics_ok(fprog->filter, fprog->len)) return -EINVAL; fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); @@ -1112,7 +1120,7 @@ int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, int err; /* Make sure new filter is there and in the right amounts. */ - if (fprog->filter == NULL) + if (!bpf_check_basics_ok(fprog->filter, fprog->len)) return -EINVAL; fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); @@ -1207,7 +1215,6 @@ static struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk) { unsigned int fsize = bpf_classic_proglen(fprog); - unsigned int bpf_fsize = bpf_prog_size(fprog->len); struct bpf_prog *prog; int err; @@ -1215,10 +1222,10 @@ struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk) return ERR_PTR(-EPERM); /* Make sure new filter is there and in the right amounts. */ - if (fprog->filter == NULL) + if (!bpf_check_basics_ok(fprog->filter, fprog->len)) return ERR_PTR(-EINVAL); - prog = bpf_prog_alloc(bpf_fsize, 0); + prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); if (!prog) return ERR_PTR(-ENOMEM); @@ -1603,9 +1610,36 @@ static const struct bpf_func_proto bpf_csum_diff_proto = { .arg5_type = ARG_ANYTHING, }; +static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb) +{ + if (skb_at_tc_ingress(skb)) + skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len); + + return dev_forward_skb(dev, skb); +} + +static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) +{ + int ret; + + if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) { + net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n"); + kfree_skb(skb); + return -ENETDOWN; + } + + skb->dev = dev; + + __this_cpu_inc(xmit_recursion); + ret = dev_queue_xmit(skb); + __this_cpu_dec(xmit_recursion); + + return ret; +} + static u64 bpf_clone_redirect(u64 r1, u64 ifindex, u64 flags, u64 r4, u64 r5) { - struct sk_buff *skb = (struct sk_buff *) (long) r1, *skb2; + struct sk_buff *skb = (struct sk_buff *) (long) r1; struct net_device *dev; if (unlikely(flags & ~(BPF_F_INGRESS))) @@ -1615,19 +1649,12 @@ static u64 bpf_clone_redirect(u64 r1, u64 ifindex, u64 flags, u64 r4, u64 r5) if (unlikely(!dev)) return -EINVAL; - skb2 = skb_clone(skb, GFP_ATOMIC); - if (unlikely(!skb2)) + skb = skb_clone(skb, GFP_ATOMIC); + if (unlikely(!skb)) return -ENOMEM; - if (flags & BPF_F_INGRESS) { - if (skb_at_tc_ingress(skb2)) - skb_postpush_rcsum(skb2, skb_mac_header(skb2), - skb2->mac_len); - return dev_forward_skb(dev, skb2); - } - - skb2->dev = dev; - return dev_queue_xmit(skb2); + return flags & BPF_F_INGRESS ? + __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb); } static const struct bpf_func_proto bpf_clone_redirect_proto = { @@ -1671,15 +1698,8 @@ int skb_do_redirect(struct sk_buff *skb) return -EINVAL; } - if (ri->flags & BPF_F_INGRESS) { - if (skb_at_tc_ingress(skb)) - skb_postpush_rcsum(skb, skb_mac_header(skb), - skb->mac_len); - return dev_forward_skb(dev, skb); - } - - skb->dev = dev; - return dev_queue_xmit(skb); + return ri->flags & BPF_F_INGRESS ? + __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb); } static const struct bpf_func_proto bpf_redirect_proto = { |