diff options
author | Jason Wang <jasowang@redhat.com> | 2013-11-13 14:00:39 +0800 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-08 07:29:12 -0800 |
commit | d485b5173b10de877781e6cabf39bee3f0bca5dc (patch) | |
tree | 371e3ea01cb336db141839249a581d9a6ae97ed9 /drivers/net/macvtap.c | |
parent | cec2b41aaf8da29ca3bb2a56a1cd67c6675ed60f (diff) |
tuntap: limit head length of skb allocated
[ Upstream commit 96f8d9ecf227638c89f98ccdcdd50b569891976c ]
We currently use hdr_len as a hint of head length which is advertised by
guest. But when guest advertise a very big value, it can lead to an 64K+
allocating of kmalloc() which has a very high possibility of failure when host
memory is fragmented or under heavy stress. The huge hdr_len also reduce the
effect of zerocopy or even disable if a gso skb is linearized in guest.
To solves those issues, this patch introduces an upper limit (PAGE_SIZE) of the
head, which guarantees an order 0 allocation each time.
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/macvtap.c')
0 files changed, 0 insertions, 0 deletions