tree c0aa05c502d3524ac974b6609a80fc796f5864ec
parent bc2f83f11c3b10fc75135c64c8cda55213354430
author Sjors Hettinga <s.a.hettinga@gmail.com> 1652802425 +0200
committer Marti Bolivar <marti.bolivar@nordicsemi.no> 1653099866 -0700

net: tcp: Correctly determine when the TCP transmit window is full

In the stack both unacked_len and send_data_total track the amount
of data for retransmission. send_data_total actually accounts the
total bytes in the buffer, where unacked_len is used to control the
retransmission progress.

Using unacked_len is sometimes reset to 0, this can lead to more data
being allowd in the send_data buffer. In worse case this can cause
depletion of the net buffers, causing a stall and crash of the connection.

The value send_data_total actually accounts the total amount of data in
the send_data buffer, so it is the proper value to used in the
tcp_window_full function.

Signed-off-by: Sjors Hettinga <s.a.hettinga@gmail.com>