Messages in this thread | | | Date | Wed, 15 Aug 2018 22:02:30 +0200 | From | Michal Kubecek <> | Subject | Re: [PATCH 4.4.y] tcp: Fix missing range_truesize enlargement in the backport |
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On Wed, Aug 15, 2018 at 01:11:21PM +0200, Greg Kroah-Hartman wrote: > On Wed, Aug 15, 2018 at 11:58:46AM +0200, Takashi Iwai wrote: > > The 4.4.y stable backport dc6ae4dffd65 for the upstream commit > > 3d4bf93ac120 ("tcp: detect malicious patterns in > > tcp_collapse_ofo_queue()") missed a line that enlarges the > > range_truesize value, which broke the whole check. > > > > Fixes: dc6ae4dffd65 ("tcp: detect malicious patterns in tcp_collapse_ofo_queue()") > > Signed-off-by: Takashi Iwai <tiwai@suse.de> > > --- > > > > Greg, this is a fix-up specific to 4.4.y stable backport that had a > > slightly different form from upstream fix. I haven't looked at the > > older trees, but 4.9.y and later took the upstream fix as is, so this > > patch isn't needed for them. > > > > The patch hasn't been tested with the real test case, though; let me > > know if the current code is intended. Thanks! > > Hm, I did the initial backport, and then Eric showed what I got wrong > and fixed that up, so being still wrong is not inconceivable at all :)
Takashi's follow-up patch is what makes the backport work the same way as the original mainline commit 3d4bf93ac120. Without it, range_truesize will be always equal to truesize of first packet in a contiguous range so that the condition
range_truesize != head->truesize
will be always false (and there would be no point having range_truesize variable at all).
Michal Kubecek
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