Commit 7cd882df authored by Rohan McLure's avatar Rohan McLure Committed by Michael Ellerman
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powerpc/64: Sanitise user registers on interrupt in pseries, POWERNV 



Cause pseries and POWERNV platforms to default to zeroising all potentially
user-defined registers when entering the kernel by means of any interrupt
source, reducing user-influence of the kernel and the likelihood or
producing speculation gadgets.

Acked-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarRohan McLure <rmclure@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221201071019.1953023-7-rmclure@linux.ibm.com
parent efe1691a

arch/powerpc/Kconfig

+1 −1
Original line number Original line Diff line number Diff line
@@ -537,7 +537,7 @@ config HOTPLUG_CPU 
config INTERRUPT_SANITIZE_REGISTERS

config INTERRUPT_SANITIZE_REGISTERS

	bool "Clear gprs on interrupt arrival"

	bool "Clear gprs on interrupt arrival"

	depends on PPC64 && ARCH_HAS_SYSCALL_WRAPPER

	depends on PPC64 && ARCH_HAS_SYSCALL_WRAPPER

	default PPC_BOOK3E_64

	default PPC_BOOK3E_64 || PPC_PSERIES || PPC_POWERNV

	help

	help

	  Reduce the influence of user register state on interrupt handlers and

	  Reduce the influence of user register state on interrupt handlers and

	  syscalls through clearing user state from registers before handling

	  syscalls through clearing user state from registers before handling