diff options
Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r-- | net/core/skbuff.c | 112 |
1 files changed, 89 insertions, 23 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 7e2e502ef519..1ba8f0163744 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -712,11 +712,10 @@ EXPORT_SYMBOL(kfree_skb_list); * * Must only be called from net_ratelimit()-ed paths. * - * Dumps up to can_dump_full whole packets if full_pkt, headers otherwise. + * Dumps whole packets if full_pkt, only headers otherwise. */ void skb_dump(const char *level, const struct sk_buff *skb, bool full_pkt) { - static atomic_t can_dump_full = ATOMIC_INIT(5); struct skb_shared_info *sh = skb_shinfo(skb); struct net_device *dev = skb->dev; struct sock *sk = skb->sk; @@ -726,9 +725,6 @@ void skb_dump(const char *level, const struct sk_buff *skb, bool full_pkt) int i, len, seg_len; if (full_pkt) - full_pkt = atomic_dec_if_positive(&can_dump_full) >= 0; - - if (full_pkt) len = skb->len; else len = min_t(int, skb->len, MAX_HEADER + 128); @@ -820,6 +816,7 @@ void skb_tx_error(struct sk_buff *skb) } EXPORT_SYMBOL(skb_tx_error); +#ifdef CONFIG_TRACEPOINTS /** * consume_skb - free an skbuff * @skb: buffer to free @@ -837,6 +834,7 @@ void consume_skb(struct sk_buff *skb) __kfree_skb(skb); } EXPORT_SYMBOL(consume_skb); +#endif /** * consume_stateless_skb - free an skbuff, assuming it is stateless @@ -893,9 +891,6 @@ void __kfree_skb_defer(struct sk_buff *skb) void napi_consume_skb(struct sk_buff *skb, int budget) { - if (unlikely(!skb)) - return; - /* Zero budget indicate non-NAPI context called us, like netpoll */ if (unlikely(!budget)) { dev_consume_skb_any(skb); @@ -2723,19 +2718,20 @@ EXPORT_SYMBOL(skb_checksum); /* Both of above in one bottle. */ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, - u8 *to, int len, __wsum csum) + u8 *to, int len) { int start = skb_headlen(skb); int i, copy = start - offset; struct sk_buff *frag_iter; int pos = 0; + __wsum csum = 0; /* Copy header. */ if (copy > 0) { if (copy > len) copy = len; csum = csum_partial_copy_nocheck(skb->data + offset, to, - copy, csum); + copy); if ((len -= copy) == 0) return csum; offset += copy; @@ -2765,7 +2761,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, vaddr = kmap_atomic(p); csum2 = csum_partial_copy_nocheck(vaddr + p_off, to + copied, - p_len, 0); + p_len); kunmap_atomic(vaddr); csum = csum_block_add(csum, csum2, pos); pos += p_len; @@ -2791,7 +2787,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, copy = len; csum2 = skb_copy_and_csum_bits(frag_iter, offset - start, - to, copy, 0); + to, copy); csum = csum_block_add(csum, csum2, pos); if ((len -= copy) == 0) return csum; @@ -3011,7 +3007,7 @@ void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to) csum = 0; if (csstart != skb->len) csum = skb_copy_and_csum_bits(skb, csstart, to + csstart, - skb->len - csstart, 0); + skb->len - csstart); if (skb->ip_summed == CHECKSUM_PARTIAL) { long csstuff = csstart + skb->csum_offset; @@ -3932,7 +3928,7 @@ normal: skb_copy_and_csum_bits(head_skb, offset, skb_put(nskb, len), - len, 0); + len); SKB_GSO_CB(nskb)->csum_start = skb_headroom(nskb) + doffset; } else { @@ -5418,8 +5414,8 @@ struct sk_buff *skb_vlan_untag(struct sk_buff *skb) skb = skb_share_check(skb, GFP_ATOMIC); if (unlikely(!skb)) goto err_free; - - if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) + /* We may access the two bytes after vlan_hdr in vlan_set_encap_proto(). */ + if (unlikely(!pskb_may_pull(skb, VLAN_HLEN + sizeof(unsigned short)))) goto err_free; vhdr = (struct vlan_hdr *)skb->data; @@ -5559,6 +5555,73 @@ int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci) } EXPORT_SYMBOL(skb_vlan_push); +/** + * skb_eth_pop() - Drop the Ethernet header at the head of a packet + * + * @skb: Socket buffer to modify + * + * Drop the Ethernet header of @skb. + * + * Expects that skb->data points to the mac header and that no VLAN tags are + * present. + * + * Returns 0 on success, -errno otherwise. + */ +int skb_eth_pop(struct sk_buff *skb) +{ + if (!pskb_may_pull(skb, ETH_HLEN) || skb_vlan_tagged(skb) || + skb_network_offset(skb) < ETH_HLEN) + return -EPROTO; + + skb_pull_rcsum(skb, ETH_HLEN); + skb_reset_mac_header(skb); + skb_reset_mac_len(skb); + + return 0; +} +EXPORT_SYMBOL(skb_eth_pop); + +/** + * skb_eth_push() - Add a new Ethernet header at the head of a packet + * + * @skb: Socket buffer to modify + * @dst: Destination MAC address of the new header + * @src: Source MAC address of the new header + * + * Prepend @skb with a new Ethernet header. + * + * Expects that skb->data points to the mac header, which must be empty. + * + * Returns 0 on success, -errno otherwise. + */ +int skb_eth_push(struct sk_buff *skb, const unsigned char *dst, + const unsigned char *src) +{ + struct ethhdr *eth; + int err; + + if (skb_network_offset(skb) || skb_vlan_tag_present(skb)) + return -EPROTO; + + err = skb_cow_head(skb, sizeof(*eth)); + if (err < 0) + return err; + + skb_push(skb, sizeof(*eth)); + skb_reset_mac_header(skb); + skb_reset_mac_len(skb); + + eth = eth_hdr(skb); + ether_addr_copy(eth->h_dest, dst); + ether_addr_copy(eth->h_source, src); + eth->h_proto = skb->protocol; + + skb_postpush_rcsum(skb, eth, sizeof(*eth)); + + return 0; +} +EXPORT_SYMBOL(skb_eth_push); + /* Update the ethertype of hdr and the skb csum value if required. */ static void skb_mod_eth_type(struct sk_buff *skb, struct ethhdr *hdr, __be16 ethertype) @@ -5620,7 +5683,7 @@ int skb_mpls_push(struct sk_buff *skb, __be32 mpls_lse, __be16 mpls_proto, lse->label_stack_entry = mpls_lse; skb_postpush_rcsum(skb, lse, MPLS_HLEN); - if (ethernet) + if (ethernet && mac_len >= ETH_HLEN) skb_mod_eth_type(skb, eth_hdr(skb), mpls_proto); skb->protocol = mpls_proto; @@ -5660,7 +5723,7 @@ int skb_mpls_pop(struct sk_buff *skb, __be16 next_proto, int mac_len, skb_reset_mac_header(skb); skb_set_network_header(skb, mac_len); - if (ethernet) { + if (ethernet && mac_len >= ETH_HLEN) { struct ethhdr *hdr; /* use mpls_hdr() to get ethertype to account for VLANs. */ @@ -5953,8 +6016,7 @@ static int pskb_carve_inside_nonlinear(struct sk_buff *skb, const u32 off, size = SKB_WITH_OVERHEAD(ksize(data)); memcpy((struct skb_shared_info *)(data + size), - skb_shinfo(skb), offsetof(struct skb_shared_info, - frags[skb_shinfo(skb)->nr_frags])); + skb_shinfo(skb), offsetof(struct skb_shared_info, frags[0])); if (skb_orphan_frags(skb, gfp_mask)) { kfree(data); return -ENOMEM; @@ -5987,9 +6049,13 @@ static int pskb_carve_inside_nonlinear(struct sk_buff *skb, const u32 off, if (skb_has_frag_list(skb)) skb_clone_fraglist(skb); - if (k == 0) { - /* split line is in frag list */ - pskb_carve_frag_list(skb, shinfo, off - pos, gfp_mask); + /* split line is in frag list */ + if (k == 0 && pskb_carve_frag_list(skb, shinfo, off - pos, gfp_mask)) { + /* skb_frag_unref() is not needed here as shinfo->nr_frags = 0. */ + if (skb_has_frag_list(skb)) + kfree_skb_list(skb_shinfo(skb)->frag_list); + kfree(data); + return -ENOMEM; } skb_release_data(skb); |