Date: Sun, 1 Jul 2007 21:11:22 -0400 From: "Vadym Chepkov" <vchepkov@gmail.com> To: "Max Laier" <max@love2party.net>, <freebsd-pf@freebsd.org> Cc: Hugo Koji Kobayashi <koji@registro.br> Subject: Re: udp fragmentation Message-ID: <002401c7bc45$e7fa89f0$c40a0a0a@chepkov.lan> References: <20070528224225.GC40678@registro.br><20070629000630.GA52912@cdnetworks.co.kr><200706291431.37159.max@love2party.net> <200706291505.05141.max@love2party.net>
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Max, I have applied the patch, seems to be working fine, thank you. Vadym Chepkov ----- Original Message ----- From: "Max Laier" <max@love2party.net> To: <freebsd-pf@freebsd.org> Cc: "Hugo Koji Kobayashi" <koji@registro.br> Sent: Friday, June 29, 2007 9:04 AM Subject: Re: udp fragmentation On Friday 29 June 2007, Max Laier wrote: > On Friday 29 June 2007, Pyun YongHyeon wrote: > > On Thu, Jun 28, 2007 at 10:56:01PM +0200, Max Laier wrote: > > > > > The only thing common about your setup seems to be the bge(4) > > > > > NIC. Can you try disabling hardware checksumming (ifconfig > > > > > -txcsum -rxcsum)? My test is over a hardware checksumming > > > > > fxp(4) card, though. > > > > > > > > Yes, this eliminated the issue. Bug in bge driver? > > > > > > Kind of - the driver claims to have done UDP checksum testing on > > > the fragment (which is impossible). The attached patch should fix > > > the issue for bge(4) and any other similar NIC. > > > > I guess bge(4) has Rx checksum offload bug on fragmented UDP > > datagrams. Since other hardwares with checksum offload capability > > does not show this issue, it could be related with UDP pseudo header > > calculation. How about disabling UDP pseudo header calculation? > > > > I don't have bge(4) hardwares so the patch is just guess work. > > In fact it doesn't seem broken at all, we would just have to do > something along the lines of ip_input.c::ip_reass() (line 1001 ff): >... > Have to ponder a bit, if this is easily possible in pf's reassembly. Works - see attached. Does anyone know of a tool to generate nasty fragments to really test this? Reordered / overlapping / etc. ? -- /"\ Best regards, | mlaier@freebsd.org \ / Max Laier | ICQ #67774661 X http://pf4freebsd.love2party.net/ | mlaier@EFnet / \ ASCII Ribbon Campaign | Against HTML Mail and News
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