Messages in this thread | | | Date | Fri, 1 Jun 2018 12:57:26 +0200 | From | Pavel Machek <> | Subject | Re: ptrval hiding -- first kernel messages look rather "interesting" |
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On Fri 2018-06-01 13:49:41, Andy Shevchenko wrote: > On Fri, Jun 1, 2018 at 1:31 PM, Pavel Machek <pavel@ucw.cz> wrote: > > Hi! > > > > v4.17 on n900: > > > > [ 0.000000] Virtual kernel memory layout: > > [ 0.000000] vector : 0xffff0000 - 0xffff1000 ( 4 kB) > > [ 0.000000] fixmap : 0xffc00000 - 0xfff00000 (3072 kB) > > [ 0.000000] vmalloc : 0xd0000000 - 0xff800000 ( 760 MB) > > [ 0.000000] lowmem : 0xc0000000 - 0xcff00000 ( 255 MB) > > [ 0.000000] pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB) > > [ 0.000000] modules : 0xbf000000 - 0xbfe00000 ( 14 MB) > > [ 0.000000] .text : 0x(ptrval) - 0x(ptrval) (8160 kB) > > [ 0.000000] .init : 0x(ptrval) - 0x(ptrval) (1024 kB) > > [ 0.000000] .data : 0x(ptrval) - 0x(ptrval) ( 309 kB) > > [ 0.000000] .bss : 0x(ptrval) - 0x(ptrval) ( 333 kB) > > [ 0.000000] NR_IRQS: 16, nr_irqs: 16, preallocated irqs: 16 > > > > I mean -- security is nice, but perhaps we should adjust the messages > > so this does not look like we are making fun of the user? > > Colleague of mine (perhaps you even know him) wrote recently a small > patch that improves kernel by 400% by removing ptr_to_id() completely. > > Okay, joking is joking, but it was a proposal to have some command > line option to enforce no-hash pointers. > I would rather enable it when one of the existing option is present > (like 'debug'), though it might alter the output in user space or > something else. > So, I have no strong opinion here.
I guess my proposal would be replacing the four lines with single line:
.text (8160 kB) .init (1024 kB) .data ( 309 kB) .bss ( 333 kB)
I'm not sure if exact addresses are normally useful, and having big table saying "redacted!" looks strange. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html [unhandled content-type:application/pgp-signature] | |