Re: WARNING in arch_install_hw_breakpoint

From: Borislav Petkov
Date: Wed Mar 27 2019 - 11:17:27 EST


On Wed, Mar 27, 2019 at 02:45:24PM +0100, Dmitry Vyukov wrote:
> And run this program:
> https://syzkaller.appspot.com/text?tag=ReproC&x=15439f27200000

Yap, that worked in my guest, after segfaulting a lot first:

[ 101.600512][ T7333] Code: Bad RIP value.
[ 101.606103][ T7337] repro[7337]: segfault at 155555585 ip 0000000155555585 sp 00007ffff7fdaf10 error 14 in repro[555555554000+1000]
[ 101.606248][ T7338] repro[7338]: segfault at 25555554e ip 000000025555554e sp 00007ffff7fdaf10 error 14 in repro[555555554000+1000]
[ 101.608498][ T7337] Code: Bad RIP value.
[ 101.610442][ T7338] Code: Bad RIP value.
[ 101.611417][ T7341] repro[7341]: segfault at 0 ip 0000000000000000 sp 00000000200002c8 error 14
[ 101.613342][ T7341] Code: Bad RIP value.
[ 101.613798][ T7345] repro[7345]: segfault at 0 ip 0000000000000000 sp 00000000200002c8 error 14
[ 101.614292][ T7342] repro[7342]: segfault at 45555554e ip 000000045555554e sp 00007ffff7f98f10 error 14 in repro[555555554000+1000]
[ 101.615809][ T7345] Code: Bad RIP value.
[ 101.616777][ T7348] repro[7348]: segfault at 155555585 ip 0000000155555585 sp 00007ffff7fdaf10 error 14 in repro[555555554000+1000]
[ 101.616802][ T7348] Code: Bad RIP value.
[ 101.617733][ T7342] Code: Bad RIP value.
[ 105.321676][T11024] ------------[ cut here ]------------
[ 105.324183][T11024] Can't find any breakpoint slot
[ 105.324229][T11024] WARNING: CPU: 0 PID: 11024 at arch/x86/kernel/hw_breakpoint.c:121 arch_install_hw_breakpoint+0x2d1/0x3a0
...

Thx.

--
Regards/Gruss,
Boris.

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