1 files changed, 28 insertions, 12 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index f88653138621..1d723de18686 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -255,11 +255,14 @@
 #include <linux/init.h>
 #include <linux/fs.h>
 #include <linux/skbuff.h>
+#include <linux/scatterlist.h>
 #include <linux/splice.h>
 #include <linux/net.h>
 #include <linux/socket.h>
 #include <linux/random.h>
 #include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/swap.h>
 #include <linux/cache.h>
 #include <linux/err.h>
 #include <linux/crypto.h>
@@ -1206,7 +1209,8 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
                 return -ENOTCONN;
         while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) {
                 if (offset < skb->len) {
-                        size_t used, len;
+                        int used;
+                        size_t len;
 
                         len = skb->len - offset;
                         /* Stop reading if we hit a patch of urgent data */
@@ -1227,7 +1231,14 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
                                 copied += used;
                                 offset += used;
                         }
-                        if (offset != skb->len)
+                        /*
+                         * If recv_actor drops the lock (e.g. TCP splice
+                         * receive) the skb pointer might be invalid when
+                         * getting here: tcp_collapse might have deleted it
+                         * while aggregating skbs from the socket queue.
+                         */
+                        skb = tcp_recv_skb(sk, seq-1, &offset);
+                        if (!skb || (offset+1 != skb->len))
                                 break;
                 }
                 if (tcp_hdr(skb)->fin) {
@@ -2105,12 +2116,15 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
                 break;
 
         case TCP_DEFER_ACCEPT:
-                if (val < 0) {
-                        err = -EINVAL;
-                } else {
-                        if (val > MAX_TCP_ACCEPT_DEFERRED)
-                                val = MAX_TCP_ACCEPT_DEFERRED;
-                        icsk->icsk_accept_queue.rskq_defer_accept = val;
+                icsk->icsk_accept_queue.rskq_defer_accept = 0;
+                if (val > 0) {
+                        /* Translate value in seconds to number of
+                         * retransmits */
+                        while (icsk->icsk_accept_queue.rskq_defer_accept < 32 &&
+                               val > ((TCP_TIMEOUT_INIT / HZ) <<
+                                       icsk->icsk_accept_queue.rskq_defer_accept))
+                                icsk->icsk_accept_queue.rskq_defer_accept++;
+                        icsk->icsk_accept_queue.rskq_defer_accept++;
                 }
                 break;
 
@@ -2292,7 +2306,8 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
                         val = (val ? : sysctl_tcp_fin_timeout) / HZ;
                 break;
         case TCP_DEFER_ACCEPT:
-                val = icsk->icsk_accept_queue.rskq_defer_accept;
+                val = !icsk->icsk_accept_queue.rskq_defer_accept ? 0 :
+                        ((TCP_TIMEOUT_INIT / HZ) << (icsk->icsk_accept_queue.rskq_defer_accept - 1));
                 break;
         case TCP_WINDOW_CLAMP:
                 val = tp->window_clamp;
@@ -2609,7 +2624,7 @@ __setup("thash_entries=", set_thash_entries);
 void __init tcp_init(void)
 {
         struct sk_buff *skb = NULL;
-        unsigned long limit;
+        unsigned long nr_pages, limit;
         int order, i, max_share;
 
         BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof(skb->cb));
@@ -2678,8 +2693,9 @@ void __init tcp_init(void)
          * is up to 1/2 at 256 MB, decreasing toward zero with the amount of
          * memory, with a floor of 128 pages.
          */
-        limit = min(nr_all_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
-        limit = (limit * (nr_all_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
+        nr_pages = totalram_pages - totalhigh_pages;
+        limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
+        limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
         limit = max(limit, 128UL);
         sysctl_tcp_mem[0] = limit / 4 * 3;
         sysctl_tcp_mem[1] = limit;