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Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r--net/core/skbuff.c172
1 files changed, 127 insertions, 45 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 1e3e0087245b..f86bf69cfb8d 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -72,7 +72,7 @@
#include <net/ip6_checksum.h>
#include <net/xfrm.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
#include <trace/events/skb.h>
#include <linux/highmem.h>
#include <linux/capability.h>
@@ -271,7 +271,6 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
atomic_set(&fclones->fclone_ref, 1);
fclones->skb2.fclone = SKB_FCLONE_CLONE;
- fclones->skb2.pfmemalloc = pfmemalloc;
}
out:
return skb;
@@ -354,7 +353,7 @@ EXPORT_SYMBOL(build_skb);
struct napi_alloc_cache {
struct page_frag_cache page;
- size_t skb_count;
+ unsigned int skb_count;
void *skb_cache[NAPI_SKB_CACHE_SIZE];
};
@@ -369,7 +368,7 @@ static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
local_irq_save(flags);
nc = this_cpu_ptr(&netdev_alloc_cache);
- data = __alloc_page_frag(nc, fragsz, gfp_mask);
+ data = page_frag_alloc(nc, fragsz, gfp_mask);
local_irq_restore(flags);
return data;
}
@@ -391,7 +390,7 @@ static void *__napi_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
{
struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
- return __alloc_page_frag(&nc->page, fragsz, gfp_mask);
+ return page_frag_alloc(&nc->page, fragsz, gfp_mask);
}
void *napi_alloc_frag(unsigned int fragsz)
@@ -441,7 +440,7 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len,
local_irq_save(flags);
nc = this_cpu_ptr(&netdev_alloc_cache);
- data = __alloc_page_frag(nc, len, gfp_mask);
+ data = page_frag_alloc(nc, len, gfp_mask);
pfmemalloc = nc->pfmemalloc;
local_irq_restore(flags);
@@ -505,7 +504,7 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
if (sk_memalloc_socks())
gfp_mask |= __GFP_MEMALLOC;
- data = __alloc_page_frag(&nc->page, len, gfp_mask);
+ data = page_frag_alloc(&nc->page, len, gfp_mask);
if (unlikely(!data))
return NULL;
@@ -655,7 +654,7 @@ static void skb_release_head_state(struct sk_buff *skb)
skb->destructor(skb);
}
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
- nf_conntrack_put(skb->nfct);
+ nf_conntrack_put(skb_nfct(skb));
#endif
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
nf_bridge_put(skb->nf_bridge);
@@ -878,9 +877,6 @@ static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
#endif
#ifdef CONFIG_NET_SCHED
CHECK_SKB_FIELD(tc_index);
-#ifdef CONFIG_NET_CLS_ACT
- CHECK_SKB_FIELD(tc_verd);
-#endif
#endif
}
@@ -1195,10 +1191,10 @@ EXPORT_SYMBOL(__pskb_copy_fclone);
int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
gfp_t gfp_mask)
{
- int i;
- u8 *data;
- int size = nhead + skb_end_offset(skb) + ntail;
+ int i, osize = skb_end_offset(skb);
+ int size = osize + nhead + ntail;
long off;
+ u8 *data;
BUG_ON(nhead < 0);
@@ -1260,6 +1256,14 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
skb->hdr_len = 0;
skb->nohdr = 0;
atomic_set(&skb_shinfo(skb)->dataref, 1);
+
+ /* It is not generally safe to change skb->truesize.
+ * For the moment, we really care of rx path, or
+ * when skb is orphaned (not attached to a socket).
+ */
+ if (!skb->sk || skb->destructor == sock_edemux)
+ skb->truesize += size - osize;
+
return 0;
nofrags:
@@ -2656,7 +2660,9 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen)
struct skb_frag_struct *fragfrom, *fragto;
BUG_ON(shiftlen > skb->len);
- BUG_ON(skb_headlen(skb)); /* Would corrupt stream */
+
+ if (skb_headlen(skb))
+ return 0;
todo = shiftlen;
from = 0;
@@ -3076,22 +3082,32 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb,
if (sg && csum && (mss != GSO_BY_FRAGS)) {
if (!(features & NETIF_F_GSO_PARTIAL)) {
struct sk_buff *iter;
+ unsigned int frag_len;
if (!list_skb ||
!net_gso_ok(features, skb_shinfo(head_skb)->gso_type))
goto normal;
- /* Split the buffer at the frag_list pointer.
- * This is based on the assumption that all
- * buffers in the chain excluding the last
- * containing the same amount of data.
+ /* If we get here then all the required
+ * GSO features except frag_list are supported.
+ * Try to split the SKB to multiple GSO SKBs
+ * with no frag_list.
+ * Currently we can do that only when the buffers don't
+ * have a linear part and all the buffers except
+ * the last are of the same length.
*/
+ frag_len = list_skb->len;
skb_walk_frags(head_skb, iter) {
+ if (frag_len != iter->len && iter->next)
+ goto normal;
if (skb_headlen(iter))
goto normal;
len -= iter->len;
}
+
+ if (len != frag_len)
+ goto normal;
}
/* GSO partial only requires that we trim off any excess that
@@ -3688,6 +3704,15 @@ static void sock_rmem_free(struct sk_buff *skb)
atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
}
+static void skb_set_err_queue(struct sk_buff *skb)
+{
+ /* pkt_type of skbs received on local sockets is never PACKET_OUTGOING.
+ * So, it is safe to (mis)use it to mark skbs on the error queue.
+ */
+ skb->pkt_type = PACKET_OUTGOING;
+ BUILD_BUG_ON(PACKET_OUTGOING == 0);
+}
+
/*
* Note: We dont mem charge error packets (no sk_forward_alloc changes)
*/
@@ -3701,6 +3726,7 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
skb->sk = sk;
skb->destructor = sock_rmem_free;
atomic_add(skb->truesize, &sk->sk_rmem_alloc);
+ skb_set_err_queue(skb);
/* before exiting rcu section, make sure dst is refcounted */
skb_dst_force(skb);
@@ -3712,21 +3738,29 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
}
EXPORT_SYMBOL(sock_queue_err_skb);
+static bool is_icmp_err_skb(const struct sk_buff *skb)
+{
+ return skb && (SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
+ SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP6);
+}
+
struct sk_buff *sock_dequeue_err_skb(struct sock *sk)
{
struct sk_buff_head *q = &sk->sk_error_queue;
- struct sk_buff *skb, *skb_next;
+ struct sk_buff *skb, *skb_next = NULL;
+ bool icmp_next = false;
unsigned long flags;
- int err = 0;
spin_lock_irqsave(&q->lock, flags);
skb = __skb_dequeue(q);
if (skb && (skb_next = skb_peek(q)))
- err = SKB_EXT_ERR(skb_next)->ee.ee_errno;
+ icmp_next = is_icmp_err_skb(skb_next);
spin_unlock_irqrestore(&q->lock, flags);
- sk->sk_err = err;
- if (err)
+ if (is_icmp_err_skb(skb) && !icmp_next)
+ sk->sk_err = 0;
+
+ if (skb_next)
sk->sk_error_report(sk);
return skb;
@@ -3769,16 +3803,21 @@ EXPORT_SYMBOL(skb_clone_sk);
static void __skb_complete_tx_timestamp(struct sk_buff *skb,
struct sock *sk,
- int tstype)
+ int tstype,
+ bool opt_stats)
{
struct sock_exterr_skb *serr;
int err;
+ BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));
+
serr = SKB_EXT_ERR(skb);
memset(serr, 0, sizeof(*serr));
serr->ee.ee_errno = ENOMSG;
serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
serr->ee.ee_info = tstype;
+ serr->opt_stats = opt_stats;
+ serr->header.h4.iif = skb->dev ? skb->dev->ifindex : 0;
if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) {
serr->ee.ee_data = skb_shinfo(skb)->tskey;
if (sk->sk_protocol == IPPROTO_TCP &&
@@ -3814,13 +3853,14 @@ void skb_complete_tx_timestamp(struct sk_buff *skb,
if (!skb_may_tx_timestamp(sk, false))
return;
- /* take a reference to prevent skb_orphan() from freeing the socket */
- sock_hold(sk);
-
- *skb_hwtstamps(skb) = *hwtstamps;
- __skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND);
-
- sock_put(sk);
+ /* Take a reference to prevent skb_orphan() from freeing the socket,
+ * but only if the socket refcount is not zero.
+ */
+ if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) {
+ *skb_hwtstamps(skb) = *hwtstamps;
+ __skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND, false);
+ sock_put(sk);
+ }
}
EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
@@ -3829,7 +3869,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
struct sock *sk, int tstype)
{
struct sk_buff *skb;
- bool tsonly;
+ bool tsonly, opt_stats = false;
if (!sk)
return;
@@ -3838,10 +3878,19 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
if (!skb_may_tx_timestamp(sk, tsonly))
return;
- if (tsonly)
- skb = alloc_skb(0, GFP_ATOMIC);
- else
+ if (tsonly) {
+#ifdef CONFIG_INET
+ if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) &&
+ sk->sk_protocol == IPPROTO_TCP &&
+ sk->sk_type == SOCK_STREAM) {
+ skb = tcp_get_timestamping_opt_stats(sk);
+ opt_stats = true;
+ } else
+#endif
+ skb = alloc_skb(0, GFP_ATOMIC);
+ } else {
skb = skb_clone(orig_skb, GFP_ATOMIC);
+ }
if (!skb)
return;
@@ -3855,7 +3904,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
else
skb->tstamp = ktime_get_real();
- __skb_complete_tx_timestamp(skb, sk, tstype);
+ __skb_complete_tx_timestamp(skb, sk, tstype, opt_stats);
}
EXPORT_SYMBOL_GPL(__skb_tstamp_tx);
@@ -3871,7 +3920,7 @@ void skb_complete_wifi_ack(struct sk_buff *skb, bool acked)
{
struct sock *sk = skb->sk;
struct sock_exterr_skb *serr;
- int err;
+ int err = 1;
skb->wifi_acked_valid = 1;
skb->wifi_acked = acked;
@@ -3881,14 +3930,15 @@ void skb_complete_wifi_ack(struct sk_buff *skb, bool acked)
serr->ee.ee_errno = ENOMSG;
serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
- /* take a reference to prevent skb_orphan() from freeing the socket */
- sock_hold(sk);
-
- err = sock_queue_err_skb(sk, skb);
+ /* Take a reference to prevent skb_orphan() from freeing the socket,
+ * but only if the socket refcount is not zero.
+ */
+ if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) {
+ err = sock_queue_err_skb(sk, skb);
+ sock_put(sk);
+ }
if (err)
kfree_skb(skb);
-
- sock_put(sk);
}
EXPORT_SYMBOL_GPL(skb_complete_wifi_ack);
@@ -4350,7 +4400,7 @@ EXPORT_SYMBOL(skb_try_coalesce);
*/
void skb_scrub_packet(struct sk_buff *skb, bool xnet)
{
- skb->tstamp.tv64 = 0;
+ skb->tstamp = 0;
skb->pkt_type = PACKET_HOST;
skb->skb_iif = 0;
skb->ignore_df = 0;
@@ -4913,3 +4963,35 @@ struct sk_buff *pskb_extract(struct sk_buff *skb, int off,
return clone;
}
EXPORT_SYMBOL(pskb_extract);
+
+/**
+ * skb_condense - try to get rid of fragments/frag_list if possible
+ * @skb: buffer
+ *
+ * Can be used to save memory before skb is added to a busy queue.
+ * If packet has bytes in frags and enough tail room in skb->head,
+ * pull all of them, so that we can free the frags right now and adjust
+ * truesize.
+ * Notes:
+ * We do not reallocate skb->head thus can not fail.
+ * Caller must re-evaluate skb->truesize if needed.
+ */
+void skb_condense(struct sk_buff *skb)
+{
+ if (skb->data_len) {
+ if (skb->data_len > skb->end - skb->tail ||
+ skb_cloned(skb))
+ return;
+
+ /* Nice, we can free page frag(s) right now */
+ __pskb_pull_tail(skb, skb->data_len);
+ }
+ /* At this point, skb->truesize might be over estimated,
+ * because skb had a fragment, and fragments do not tell
+ * their truesize.
+ * When we pulled its content into skb->head, fragment
+ * was freed, but __pskb_pull_tail() could not possibly
+ * adjust skb->truesize, not knowing the frag truesize.
+ */
+ skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
+}