tcp: use signed arithmetic in tcp_rtx_probe0_timed_out()

Due to timer wheel implementation, a timer will usually fire
after its schedule.

For instance, for HZ=1000, a timeout between 512ms and 4s
has a granularity of 64ms.
For this range of values, the extra delay could be up to 63ms.

For TCP, this means that tp->rcv_tstamp may be after
inet_csk(sk)->icsk_timeout whenever the timer interrupt
finally triggers, if one packet came during the extra delay.

We need to make sure tcp_rtx_probe0_timed_out() handles this case.

Fixes: e89688e3e978 ("net: tcp: fix unexcepted socket die when snd_wnd is 0")
Signed-off-by: Eric Dumazet <[email protected]>
Cc: Menglong Dong <[email protected]>
Acked-by: Neal Cardwell <[email protected]>
Reviewed-by: Jason Xing <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

0 files changed, 0 insertions, 0 deletions