linux-toradex.git/net/core/skbuff.c, branch v3.2.62

skbuff: skb_segment: orphan frags before copying

2014-07-11T12:34:00+00:00

commit 1fd819ecb90cc9b822cd84d3056ddba315d3340f upstream.

skb_segment copies frags around, so we need
to copy them carefully to avoid accessing
user memory after reporting completion to userspace
through a callback.

skb_segment doesn't normally happen on datapath:
TSO needs to be disabled - so disabling zero copy
in this case does not look like a big deal.

Signed-off-by: Michael S. Tsirkin 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.2.  As skb_segment() only supports page-frags *or* a
 frag list, there is no need for the additional frag_skb pointer or the
 preparatory renaming.]
Signed-off-by: Ben Hutchings

skbuff: export skb_copy_ubufs

2014-07-11T12:34:00+00:00

commit dcc0fb782b3a6e2abfeaaeb45dd88ed09596be0f upstream.

Export skb_copy_ubufs so that modules can orphan frags.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

skb: Add inline helper for getting the skb end offset from head

2014-06-09T12:29:00+00:00

[ Upstream commit ec47ea82477404631d49b8e568c71826c9b663ac ]

With the recent changes for how we compute the skb truesize it occurs to me
we are probably going to have a lot of calls to skb_end_pointer -
skb->head.  Instead of running all over the place doing that it would make
more sense to just make it a separate inline skb_end_offset(skb) that way
we can return the correct value without having gcc having to do all the
optimization to cancel out skb->head - skb->head.

Signed-off-by: Alexander Duyck 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: core: don't account for udp header size when computing seglen

2014-06-09T12:28:55+00:00

[ Upstream commit 6d39d589bb76ee8a1c6cde6822006ae0053decff ]

In case of tcp, gso_size contains the tcpmss.

For UFO (udp fragmentation offloading) skbs, gso_size is the fragment
payload size, i.e. we must not account for udp header size.

Otherwise, when using virtio drivers, a to-be-forwarded UFO GSO packet
will be needlessly fragmented in the forward path, because we think its
individual segments are too large for the outgoing link.

Fixes: fe6cc55f3a9a053 ("net: ip, ipv6: handle gso skbs in forwarding path")
Cc: Eric Dumazet 
Reported-by: Tobias Brunner 
Signed-off-by: Florian Westphal 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: add and use skb_gso_transport_seglen()

2014-04-09T01:20:45+00:00

commit de960aa9ab4decc3304959f69533eef64d05d8e8 upstream.

[ no skb_gso_seglen helper in 3.4, leave tbf alone ]

This moves part of Eric Dumazets skb_gso_seglen helper from tbf sched to
skbuff core so it may be reused by upcoming ip forwarding path patch.

Signed-off-by: Florian Westphal 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

fuse: fix pipe_buf_operations

2014-04-01T23:58:44+00:00

commit 28a625cbc2a14f17b83e47ef907b2658576a32aa upstream.

Having this struct in module memory could Oops when if the module is
unloaded while the buffer still persists in a pipe.

Since sock_pipe_buf_ops is essentially the same as fuse_dev_pipe_buf_steal
merge them into nosteal_pipe_buf_ops (this is the same as
default_pipe_buf_ops except stealing the page from the buffer is not
allowed).

Reported-by: Al Viro 
Signed-off-by: Miklos Szeredi 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

splice: fix racy pipe->buffers uses

2012-07-12T03:31:59+00:00

commit 047fe3605235888f3ebcda0c728cb31937eadfe6 upstream.

Dave Jones reported a kernel BUG at mm/slub.c:3474! triggered
by splice_shrink_spd() called from vmsplice_to_pipe()

commit 35f3d14dbbc5 (pipe: add support for shrinking and growing pipes)
added capability to adjust pipe->buffers.

Problem is some paths don't hold pipe mutex and assume pipe->buffers
doesn't change for their duration.

Fix this by adding nr_pages_max field in struct splice_pipe_desc, and
use it in place of pipe->buffers where appropriate.

splice_shrink_spd() loses its struct pipe_inode_info argument.

Reported-by: Dave Jones 
Signed-off-by: Eric Dumazet 
Cc: Jens Axboe 
Cc: Alexander Viro 
Cc: Tom Herbert 
Tested-by: Dave Jones 
Signed-off-by: Jens Axboe 
[bwh: Backported to 3.2:
 - Adjust context in vmsplice_to_pipe()
 - Update one more call to splice_shrink_spd(), from skb_splice_bits()]
Signed-off-by: Ben Hutchings

net: allow pskb_expand_head() to get maximum tailroom

2012-05-11T12:14:22+00:00

[ Upstream commit 87151b8689d890dfb495081f7be9b9e257f7a2df ]

Marc Merlin reported many order-1 allocations failures in TX path on its
wireless setup, that dont make any sense with MTU=1500 network, and non
SG capable hardware.

Turns out part of the problem comes from pskb_expand_head() not using
ksize() to get exact head size given by kmalloc(). Doing the same thing
than __alloc_skb() allows more tailroom in skb and can prevent future
reallocations.

As a bonus, struct skb_shared_info becomes cache line aligned.

Reported-by: Marc MERLIN 
Tested-by: Marc MERLIN 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: fix a race in sock_queue_err_skb()

2012-05-11T12:14:21+00:00

[ Upstream commit 110c43304db6f06490961529536c362d9ac5732f ]

As soon as an skb is queued into socket error queue, another thread
can consume it, so we are not allowed to reference skb anymore, or risk
use after free.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: correct comments of skb_shift

2011-11-22T21:18:43+00:00

when skb_shift, we want to shift paged data from skb to tgt frag area.
Original comments revert the shift order

Signed-off-by: Feng King 
Signed-off-by: David S. Miller