Messages in this thread | | | Subject | Re: [PATCH v4 00/10] Function Granular KASLR | From | Joe Lawrence <> | Date | Mon, 3 Aug 2020 14:17:41 -0400 |
| |
On 8/3/20 1:45 PM, Kees Cook wrote: > On Mon, Aug 03, 2020 at 02:39:32PM +0300, Evgenii Shatokhin wrote: >> There are at least 2 places where high-order memory allocations might happen >> during module loading. Such allocations may fail if memory is fragmented, >> while physically contiguous memory areas are not really needed there. I >> suggest to switch to kvmalloc/kvfree there. > > While this does seem to be the right solution for the extant problem, I > do want to take a moment and ask if the function sections need to be > exposed at all? What tools use this information, and do they just want > to see the bounds of the code region? (i.e. the start/end of all the > .text* sections) Perhaps .text.* could be excluded from the sysfs > section list? >
[[cc += FChE, see [0] for Evgenii's full mail ]]
It looks like debugging tools like systemtap [1], gdb [2] and its add-symbol-file cmd, etc. peek at the /sys/module/<MOD>/section/ info.
But yeah, it would be preferable if we didn't export a long sysfs representation if nobody actually needs it.
[0] https://lore.kernel.org/lkml/e9c4d88b-86db-47e9-4299-3fac45a7e3fd@virtuozzo.com/ [1] https://fossies.org/linux/systemtap/staprun/staprun.c [2] https://www.oreilly.com/library/view/linux-device-drivers/0596005903/ch04.html#linuxdrive3-CHP-4-SECT-6.1
-- Joe
| |