PacketData should not be modified and should be treated readonly because it
represents packet payload. The old DeleteFront method allowed callers to modify
the underlying buffer which should not be allowed.
Added a way to consume from the PacketData instead of deleting from it.
Updated call points to use that instead.
Reported-by: syzbot+faee5cb350f769a52d1b@syzkaller.appspotmail.com
PiperOrigin-RevId: 399268473
Earlier PacketBuffer.Clone() would do a shallow top level copy of the packet
buffer - which involved sharing the *buffer.Buffer between packets. Reading
or writing to the buffer in one packet would impact the other.
This caused modifications in one packet to affect the other's pkt.Views() which
is not desired. Change the clone to do a deeper copy of the underlying buffer
list and buffer pointers. The payload buffers (which are immutable) are still
shared. This change makes the Clone() operation more expensive as we now need to
allocate the entire buffer list.
Added unit test to test integrity of packet data after cloning.
Reported-by: syzbot+7ffff9a82a227b8f2e31@syzkaller.appspotmail.com
Reported-by: syzbot+7d241de0d9072b2b6075@syzkaller.appspotmail.com
Reported-by: syzbot+212bc4d75802fa461521@syzkaller.appspotmail.com
PiperOrigin-RevId: 390277713
headerOffset() is incorrectly taking account of previous push(), so it thinks
there is more data to consume. This change switches to use pk.reserved as
pivot point.
Reported-by: syzbot+64fef9acd509976f9ce7@syzkaller.appspotmail.com
PiperOrigin-RevId: 373846283
Benchmark iperf3:
Before After
native->runsc 5.14 5.01 (Gbps)
runsc->native 4.15 4.07 (Gbps)
It did introduce overhead, mainly at the bridge between pkg/buffer and
VectorisedView, the ExtractVV method. Once endpoints start migrating away from
VV, this overhead will be gone.
Updates #2404
PiperOrigin-RevId: 373651666
... it may now invalidate backing slice references
This is currently safe because TrimFront() in VectorisedView only shrinks the
view. This may not hold under the a different buffer implementation.
Reordering method calls order to allow this.
PiperOrigin-RevId: 371167610
One of the preparation to decouple underlying buffer implementation.
There are still some methods that tie to VectorisedView, and they will be
changed gradually in later CLs.
This CL also introduce a new ICMPv6ChecksumParams to replace long list of
parameters when calling ICMPv6Checksum, aiming to be more descriptive.
PiperOrigin-RevId: 360778149
Formerly, when a packet is constructed or parsed, all headers are set by the
client code. This almost always involved prepending to pk.Header buffer or
trimming pk.Data portion. This is known to prone to bugs, due to the complexity
and number of the invariants assumed across netstack to maintain.
In the new PacketHeader API, client will call Push()/Consume() method to
construct/parse an outgoing/incoming packet. All invariants, such as slicing
and trimming, are maintained by the API itself.
NewPacketBuffer() is introduced to create new PacketBuffer. Zero value is no
longer valid.
PacketBuffer now assumes the packet is a concatenation of following portions:
* LinkHeader
* NetworkHeader
* TransportHeader
* Data
Any of them could be empty, or zero-length.
PiperOrigin-RevId: 326507688
Ayush Ranjan
Ting-Yu Wang