Are such messages something to worry about? What do they mean? Example from dmesg log:

[422949.356062] TCP: Peer 79.22.114.39:60467/9001 unexpectedly shrunk window 2565384113:2565389251 (repaired) [427073.032013] TCP: Peer 217.20.253.198:17482/9001 unexpectedly shrunk window 2017146666:2017147597 (repaired) [478256.668534] TCP: Peer 2.236.7.28:49367/9001 unexpectedly shrunk window 176191274:176194194 (repaired) [502615.724129] TCP: Peer 217.20.253.198:53308/9001 unexpectedly shrunk window 792267503:792268436 (repaired) [514591.656053] TCP: Peer 217.20.253.198:63743/9001 unexpectedly shrunk window 445257517:445258452 (repaired) [527753.064036] TCP: Peer 94.38.5.188:49377/9001 unexpectedly shrunk window 2291195973:2291197433 (repaired) [633078.304041] TCP: Peer 87.89.75.107:59567/9001 unexpectedly shrunk window 3718547610:3718553466 (repaired) [633079.672021] TCP: Peer 87.89.75.107:59567/9001 unexpectedly shrunk window 3718547610:3718553466 (repaired) [673170.600037] TCP: Peer 82.89.173.120:50392/9001 unexpectedly shrunk window 2473022599:2473024051 (repaired) [714540.672036] TCP: Peer 217.20.253.198:20805/9001 unexpectedly shrunk window 3814426018:3814426947 (repaired) [755391.792076] TCP: Peer 79.223.168.103:61238/9001 unexpectedly shrunk window 2799388466:2799406672 (repaired) [755392.864013] TCP: Peer 79.223.168.103:61238/9001 unexpectedly shrunk window 2799388466:2799406672 (repaired)