On Wed, May 16, 2018 at 12:15:36AM +0100, Ben Hutchings wrote: > On Wed, 2018-04-11 at 20:35 +0200, Greg Kroah-Hartman wrote: > > 4.4-stable review patch. If anyone has any objections, please let me know. > > > > ------------------ > > > > > From: Will Deacon <will.deacon@xxxxxxx> > > > > > > [ Upstream commit 5f16a046f8e144c294ef98cd29d9458b5f8273e5 ] > > > > FUTEX_OP_OPARG_SHIFT instructs the futex code to treat the 12-bit oparg > > field as a shift value, potentially leading to a left shift value that > > is negative or with an absolute value that is significantly larger then > > the size of the type. UBSAN chokes with: > [...] > > Whilst I think this catches all of the issues, I'd much prefer to remove > > this stuff, as I think it's unused and the bugs are copy-pasted between > > a bunch of architectures. > [...] > > Indeed. That more complete fix was done upstream by: > > commit 30d6e0a4190d37740e9447e4e4815f06992dd8c3 > Author: Jiri Slaby <jslaby@xxxxxxx> > Date: Thu Aug 24 09:31:05 2017 +0200 > > futex: Remove duplicated code and fix undefined behaviour > > It's a bit big for stable - though most of the changes are deletions. > What do you think? I think it makes a lot of sense, I've done the backport now, thanks. greg k-h
