Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[cascardo/linux.git] / net / core / filter.c

diff --git a/net/core/filter.c b/net/core/filter.c
index 68adb5f..cb9fc16 100644 (file)
--- 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 = {
@@ -2085,7 +2105,8 @@ static bool __is_valid_access(int off, int size, enum bpf_access_type type)
 }
 
 static bool sk_filter_is_valid_access(int off, int size,
-                                     enum bpf_access_type type)
+                                     enum bpf_access_type type,
+                                     enum bpf_reg_type *reg_type)
 {
        switch (off) {
        case offsetof(struct __sk_buff, tc_classid):
@@ -2108,7 +2129,8 @@ static bool sk_filter_is_valid_access(int off, int size,
 }
 
 static bool tc_cls_act_is_valid_access(int off, int size,
-                                      enum bpf_access_type type)
+                                      enum bpf_access_type type,
+                                      enum bpf_reg_type *reg_type)
 {
        if (type == BPF_WRITE) {
                switch (off) {
@@ -2123,6 +2145,16 @@ static bool tc_cls_act_is_valid_access(int off, int size,
                        return false;
                }
        }
+
+       switch (off) {
+       case offsetof(struct __sk_buff, data):
+               *reg_type = PTR_TO_PACKET;
+               break;
+       case offsetof(struct __sk_buff, data_end):
+               *reg_type = PTR_TO_PACKET_END;
+               break;
+       }
+
        return __is_valid_access(off, size, type);
 }