[PATCH v3 2/2] kasan, arm64: fix pointer tags in KASAN reports

Andrey Konovalov andreyknvl at google.com
Fri Jan 15 13:08:59 EST 2021


On Fri, Jan 15, 2021 at 6:59 PM Catalin Marinas <catalin.marinas at arm.com> wrote:
>
> On Fri, Jan 15, 2021 at 06:41:53PM +0100, Andrey Konovalov wrote:
> > As of the "arm64: expose FAR_EL1 tag bits in siginfo" patch, the address
> > that is passed to report_tag_fault has pointer tags in the format of 0x0X,
> > while KASAN uses 0xFX format (note the difference in the top 4 bits).
> >
> > Fix up the pointer tag for kernel pointers in do_tag_check_fault by
> > setting them to the same value as bit 55. Explicitly use __untagged_addr()
> > instead of untagged_addr(), as the latter doesn't affect TTBR1 addresses.
> >
> > Link: https://linux-review.googlesource.com/id/I9ced973866036d8679e8f4ae325de547eb969649
>
> Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>
>
> Unless there are other comments, I'll queue this for -rc5 through the
> arm64 tree (I already finalised the arm64 for-next/fixes branch for this
> week).

Sounds good, thank you!



More information about the linux-arm-kernel mailing list