Re: [PATCH] hw/net: Discard overly fragmented packets

[Jason Wang <jasowang@redhat.com>]

在 2021/8/4 上午9:43, Jason Wang 写道:
>
> 在 2021/8/3 下午5:51, Philippe Mathieu-Daudé 写道:
>> On 8/3/21 11:33 AM, Thomas Huth wrote:
>>> On 05/07/2021 10.40, Philippe Mathieu-Daudé wrote:
>>>> Our infrastructure can handle fragmented packets up to
>>>> NET_MAX_FRAG_SG_LIST (64) pieces. This hard limit has
>>>> been proven enough in production for years. If it is
>>>> reached, it is likely an evil crafted packet. Discard it.
>>>>
>>>> Include the qtest reproducer provided by Alexander Bulekov:
>>>>
>>>>     $ make check-qtest-i386
>>>>     ...
>>>>     Running test qtest-i386/fuzz-vmxnet3-test
>>>>     qemu-system-i386: net/eth.c:334: void
>>>> eth_setup_ip4_fragmentation(const void *, size_t, void *, size_t,
>>>> size_t, size_t, _Bool):
>>>>     Assertion `frag_offset % IP_FRAG_UNIT_SIZE == 0' failed.
>>>>
>>>> Cc: qemu-stable@nongnu.org
>>>> Reported-by: OSS-Fuzz (Issue 35799)
>>>> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/460
>>>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>>>> ---
>>>>    hw/net/net_tx_pkt.c             |   8 ++
>>>>    tests/qtest/fuzz-vmxnet3-test.c | 195 
>>>> ++++++++++++++++++++++++++++++++
>>>>    MAINTAINERS                     |   1 +
>>>>    tests/qtest/meson.build         |   1 +
>>>>    4 files changed, 205 insertions(+)
>>>>    create mode 100644 tests/qtest/fuzz-vmxnet3-test.c
>>> Reviewed-by: Thomas Huth <thuth@redhat.com>
>>>
>>> Jason, I think this would even still qualify for QEMU v6.1 ?
>> Yes, easy one for 6.1.
>
>
> Yes, this will be included for rc3.
>
> Thanks


For some reasons it misses rc3.

I will include it for 6.2.

Sorry.


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