** Description changed: Binary package hint: tftp-hpa Because of Sorcerer's Apprentice bug retransmition of wrong ACK in tftp_sendfile function was omited. So if one packet, that tftp client will send to the tfto server will be lost, transfer will always fails! Why? If tftp server has lower retransmition timeout (per packet), than the server will be allways sending the ACK of last received packet (retransmition timeout on server side). So the bug on the client side is: restart of the retransmition timer (rexmt) on wrong received ACK packet! This bug can make tftp unusefull. + + Tftp trace: + received ACK <block=78> + sent DATA <block=79, 512 bytes> + received ACK <block=79> + sent DATA <block=80, 512 bytes> + received ACK <block=79> + received ACK <block=79> + received ACK <block=79> + received ACK <block=79> + sent DATA <block=80, 512 bytes> + sent DATA <block=80, 512 bytes> + sent DATA <block=80, 512 bytes> + sent DATA <block=80, 512 bytes> + Transfer timed out. + + Servers time out is 2 second and default tftp-hpa client time out is 5 seconds. + One more thing...Only when tftp server has stoped sending the ACK's onyl that rexmt timer was working on tftp-hpa client. So socket on server side was already closed. Server has send ICMP about it, but not reaction on client side!
** Description changed: Binary package hint: tftp-hpa Because of Sorcerer's Apprentice bug retransmition of wrong ACK in tftp_sendfile function was omited. So if one packet, that tftp client will send to the tfto server will be lost, transfer will always fails! Why? If tftp server has lower retransmition timeout (per packet), than the server will be allways sending the ACK of last received packet (retransmition timeout on server side). So the bug on the client side is: restart of the retransmition timer (rexmt) on wrong received ACK packet! This bug can make tftp unusefull. Tftp trace: received ACK <block=78> sent DATA <block=79, 512 bytes> received ACK <block=79> sent DATA <block=80, 512 bytes> received ACK <block=79> received ACK <block=79> received ACK <block=79> received ACK <block=79> sent DATA <block=80, 512 bytes> sent DATA <block=80, 512 bytes> sent DATA <block=80, 512 bytes> sent DATA <block=80, 512 bytes> Transfer timed out. - Servers time out is 2 second and default tftp-hpa client time out is 5 seconds. + Server's retransmition timeout is 2 second and default tftp-hpa client timeout is 5 seconds. One more thing...Only when tftp server has stoped sending the ACK's onyl that rexmt timer was working on tftp-hpa client. So socket on server side was already closed. Server has send ICMP about it, but not reaction on client side! -- retransmition timer (rexmt) restart on wrong ACK https://bugs.launchpad.net/bugs/246501 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
