@@ -4354,19 +4354,34 @@ static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, int
int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
{
struct sk_buff *skb;
+ int err = -ENOMEM;
+ int data_len = 0;
bool fragstolen;
if (size == 0)
return 0;
- skb = alloc_skb(size, sk->sk_allocation);
+ if (size > PAGE_SIZE) {
+ int npages = min_t(size_t, size >> PAGE_SHIFT, MAX_SKB_FRAGS);
+
+ data_len = npages << PAGE_SHIFT;
+ size = data_len + (size & ~PAGE_MASK);
+ }
+ skb = alloc_skb_with_frags(size - data_len, data_len,
+ PAGE_ALLOC_COSTLY_ORDER,
+ &err, sk->sk_allocation);
if (!skb)
goto err;
+ skb_put(skb, size - data_len);
+ skb->data_len = data_len;
+ skb->len = size;
+
if (tcp_try_rmem_schedule(sk, skb, skb->truesize))
goto err_free;
- if (memcpy_from_msg(skb_put(skb, size), msg, size))
+ err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size);
+ if (err)
goto err_free;
TCP_SKB_CB(skb)->seq = tcp_sk(sk)->rcv_nxt;
@@ -4382,7 +4397,8 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size)
err_free:
kfree_skb(skb);
err:
- return -ENOMEM;
+ return err;
+
}
static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
This is a note to let you know that I have just added a patch titled tcp: fix potential huge kmalloc() calls in TCP_REPAIR to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt12. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 338d2260b4ed3267c7c12114303b862d73500360 Mon Sep 17 00:00:00 2001 From: Eric Dumazet <edumazet@google.com> Date: Wed, 18 Nov 2015 21:03:33 -0800 Subject: tcp: fix potential huge kmalloc() calls in TCP_REPAIR commit 5d4c9bfbabdb1d497f21afd81501e5c54b0c85d9 upstream. tcp_send_rcvq() is used for re-injecting data into tcp receive queue. Problems : - No check against size is performed, allowed user to fool kernel in attempting very large memory allocations, eventually triggering OOM when memory is fragmented. - In case of fault during the copy we do not return correct errno. Lets use alloc_skb_with_frags() to cook optimal skbs. Fixes: 292e8d8c8538 ("tcp: Move rcvq sending to tcp_input.c") Fixes: c0e88ff0f256 ("tcp: Repair socket queues") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- net/ipv4/tcp_input.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) -- 1.9.1