Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android

[firefly-linux-kernel-4.4.55.git] / net / core / filter.c

diff --git a/net/core/filter.c b/net/core/filter.c
index f393a22b9d5049b3161812105474bd93d72db965..e94355452166c8f9864a153c2f552ff37c9c756b 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -52,9 +52,10 @@
 #include <net/dst.h>
 
 /**
- *     sk_filter - run a packet through a socket filter
+ *     sk_filter_trim_cap - run a packet through a socket filter
  *     @sk: sock associated with &sk_buff
  *     @skb: buffer to filter
+ *     @cap: limit on how short the eBPF program may trim the packet
  *
  * Run the eBPF program and then cut skb->data to correct size returned by
  * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
@@ -63,7 +64,7 @@
  * be accepted or -EPERM if the packet should be tossed.
  *
  */
-int sk_filter(struct sock *sk, struct sk_buff *skb)
+int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
 {
        int err;
        struct sk_filter *filter;
@@ -84,14 +85,13 @@ int sk_filter(struct sock *sk, struct sk_buff *skb)
        filter = rcu_dereference(sk->sk_filter);
        if (filter) {
                unsigned int pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
-
-               err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
+               err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
        }
        rcu_read_unlock();
 
        return err;
 }
-EXPORT_SYMBOL(sk_filter);
+EXPORT_SYMBOL(sk_filter_trim_cap);
 
 static u64 __skb_get_pay_offset(u64 ctx, u64 a, u64 x, u64 r4, u64 r5)
 {
@@ -1275,9 +1275,7 @@ static u64 bpf_skb_store_bytes(u64 r1, u64 r2, u64 r3, u64 r4, u64 flags)
         */
        if (unlikely((u32) offset > 0xffff || len > sizeof(buf)))
                return -EFAULT;
-
-       if (unlikely(skb_cloned(skb) &&
-                    !skb_clone_writable(skb, offset + len)))
+       if (unlikely(skb_try_make_writable(skb, offset + len)))
                return -EFAULT;
 
        ptr = skb_header_pointer(skb, offset, len, buf);
@@ -1321,8 +1319,7 @@ static u64 bpf_l3_csum_replace(u64 r1, u64 r2, u64 from, u64 to, u64 flags)
        if (unlikely((u32) offset > 0xffff))
                return -EFAULT;
 
-       if (unlikely(skb_cloned(skb) &&
-                    !skb_clone_writable(skb, offset + sizeof(sum))))
+       if (unlikely(skb_try_make_writable(skb, offset + sizeof(sum))))
                return -EFAULT;
 
        ptr = skb_header_pointer(skb, offset, sizeof(sum), &sum);
@@ -1367,9 +1364,7 @@ static u64 bpf_l4_csum_replace(u64 r1, u64 r2, u64 from, u64 to, u64 flags)
 
        if (unlikely((u32) offset > 0xffff))
                return -EFAULT;
-
-       if (unlikely(skb_cloned(skb) &&
-                    !skb_clone_writable(skb, offset + sizeof(sum))))
+       if (unlikely(skb_try_make_writable(skb, offset + sizeof(sum))))
                return -EFAULT;
 
        ptr = skb_header_pointer(skb, offset, sizeof(sum), &sum);
@@ -1554,6 +1549,13 @@ bool bpf_helper_changes_skb_data(void *func)
                return true;
        if (func == bpf_skb_vlan_pop)
                return true;
+       if (func == bpf_skb_store_bytes)
+               return true;
+       if (func == bpf_l3_csum_replace)
+               return true;
+       if (func == bpf_l4_csum_replace)
+               return true;
+
        return false;
 }