On Wed, Mar 23, 2022 at 03:42:34PM +0000, Matthew Wilcox wrote: > On Wed, Mar 23, 2022 at 08:40:30AM -0700, Kees Cook wrote: > > On Wed, Mar 23, 2022 at 08:14:10AM +0100, Christoph Hellwig wrote: > > > The actual warning is; > > > > > > [ 34.496096][ T331] usercopy: Kernel memory overwrite attempt detected to spans multiple pages (off set 0, size 6)! > > > > > > This is for the cmnd field in struct scsi_cmnd, which is allocated by > > > the block layer as part of the request allocator. So with a specific > > > packing it can legitimately span pages. > > > > > > Kees: how can we annotate that this is ok? > > > > The main problem is that CONFIG_HARDENED_USERCOPY_PAGESPAN=y is broken > > (and nothing should be setting it). > > > > This series removes it: > > https://lore.kernel.org/linux-hardening/20220110231530.665970-1-willy@xxxxxxxxxxxxx/ > > > > Matthew, what's the status of that series? Will it make the current > > merge window? > > I thought you were going to merge it! I haven't put it in any of my > public trees. LOL. Okay, you'd mentioned another check, so I wasn't sure. I can go ahead and snag it, but I'll likely wait until the next window and let it live in -next for a while, unless you think it should get YOLOed in. :) -Kees -- Kees Cook
