[ovs-discuss] ctx->xin-packet overlap

[William Tu]

On Mon, May 18, 2020 at 7:10 AM Luca Mancini <luca.mancini at outlook.com> wrote:
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> Hi William,
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> Thanks for replying so promptly.
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> I’m still not quite sure what you mean, when I print I use:
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> VLOG_ERR(   “%s”     ,      (char *) dp_packet_get_udp_payload(dp_packet_buff[index])     );
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> Why would the second packet received assigned from ctx->xin->packet and stored in dp_packet_buff[index + 1] overlap with the first packet.
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> So using the example from before upon first packet:
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> 1. Index=0
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> 2. Ctx->xin->packet = “everyone”
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> 3. dp_packet_buff[0] = {“Everyone”}
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> 4. print with VLOG_ERR as above
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> 5. index++
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> 6. Ctx->xin->packet = “hello”
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> 7. But dp_packet_buff[1] ={“hello ne”} instead of {“hello”}
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> Isn’t the problem due to ctx->xin->packet being overwritten by subsequent packets? To explain better, on point 6 the actual packet contained in ctx->xin-packet is “hello ne” and not “hello”
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Oh, I see your point.
Maybe you can try add a break point using gdb, and see where the memory
address is when assigning string to different indexes.
William