diff options
| author | Ayush Ranjan <ayushranjan@google.com> | 2021-08-11 20:15:34 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-08-11 20:18:19 -0700 |
| commit | 6d0b40b1d159a96ba96a26f8095b9b94f3eb2dc0 (patch) | |
| tree | 2383ff01af68fbb1ea7b904ff7db27db7e91325d /pkg/buffer | |
| parent | 4249ba85068e7a398187af6c87daca2172ed25e5 (diff) | |
[op] Make PacketBuffer Clone() do a deeper copy.
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
Diffstat (limited to 'pkg/buffer')
| -rw-r--r-- | pkg/buffer/view.go | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/pkg/buffer/view.go b/pkg/buffer/view.go index 7bcfcd543..a4610f977 100644 --- a/pkg/buffer/view.go +++ b/pkg/buffer/view.go @@ -378,6 +378,20 @@ func (v *View) Copy() (other View) { return } +// Clone makes a more shallow copy compared to Copy. The underlying payload +// slice (buffer.data) is shared but the buffers themselves are copied. +func (v *View) Clone() *View { + other := &View{ + size: v.size, + } + for buf := v.data.Front(); buf != nil; buf = buf.Next() { + newBuf := other.pool.getNoInit() + *newBuf = *buf + other.data.PushBack(newBuf) + } + return other +} + // Apply applies the given function across all valid data. func (v *View) Apply(fn func([]byte)) { for buf := v.data.Front(); buf != nil; buf = buf.Next() { |