linux/arch/arm64/kernel
Mark Rutland 0d97e6d802 arm64: kasan: clear stale stack poison
Functions which the compiler has instrumented for KASAN place poison on
the stack shadow upon entry and remove this poison prior to returning.

In the case of cpuidle, CPUs exit the kernel a number of levels deep in
C code.  Any instrumented functions on this critical path will leave
portions of the stack shadow poisoned.

If CPUs lose context and return to the kernel via a cold path, we
restore a prior context saved in __cpu_suspend_enter are forgotten, and
we never remove the poison they placed in the stack shadow area by
functions calls between this and the actual exit of the kernel.

Thus, (depending on stackframe layout) subsequent calls to instrumented
functions may hit this stale poison, resulting in (spurious) KASAN
splats to the console.

To avoid this, clear any stale poison from the idle thread for a CPU
prior to bringing a CPU online.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-09 15:43:42 -08:00
..
vdso arm64: build vdso without libgcov 2015-11-12 15:18:07 +00:00
.gitignore
acpi.c Power management and ACPI updates for v4.4-rc1 2015-11-04 18:10:13 -08:00
alternative.c arm64: mm: fold alternatives into .init 2015-12-10 17:36:08 +00:00
arm64ksyms.c ARM: 8480/2: arm64: add implementation for arm-smccc 2016-01-04 16:24:45 +00:00
armv8_deprecated.c arm64: add __init/__initdata section marker to some functions/variables 2015-12-02 12:17:11 +00:00
asm-offsets.c * s390: Support for runtime instrumentation within guests, 2016-01-12 13:22:12 -08:00
cacheinfo.c arm64: kernel: add support for cpu cache information 2015-01-15 11:55:07 +00:00
cpu_errata.c arm64: KVM: Add workaround for Cortex-A57 erratum 834220 2015-11-24 17:58:14 +01:00
cpu_ops.c arm64: force CONFIG_SMP=y and remove redundant #ifdefs 2015-07-27 11:08:40 +01:00
cpufeature.c arm64: add __init/__initdata section marker to some functions/variables 2015-12-02 12:17:11 +00:00
cpuidle.c arm64: cpuidle: add __init section marker to arm_cpuidle_init 2015-07-02 17:44:27 +01:00
cpuinfo.c arm64: restore bogomips information in /proc/cpuinfo 2015-11-19 17:57:18 +00:00
debug-monitors.c arm64: debug: re-enable irqs before sending breakpoint SIGTRAP 2016-02-10 16:05:28 +00:00
efi-entry.S arm64/efi: isolate EFI stub from the kernel proper 2015-10-12 16:20:12 +01:00
efi.c arm64/efi: refactor EFI init and runtime code for reuse by 32-bit ARM 2015-12-09 16:57:23 +00:00
entry32.S arm64: entry32: remove pointless register assignment 2015-07-10 16:47:13 +01:00
entry-fpsimd.S
entry-ftrace.S arm64: ftrace: fix function_graph tracer panic 2015-10-02 11:12:56 +01:00
entry.S arm64: entry: remove pointless SPSR mode check 2016-01-06 15:40:38 +00:00
fpsimd.c arm64: add __init/__initdata section marker to some functions/variables 2015-12-02 12:17:11 +00:00
ftrace.c arm64: ftrace: modify a stack frame in a safe way 2015-12-21 17:26:01 +00:00
head.S arm64: kernel: fix architected PMU registers unconditional access 2016-01-25 11:09:06 +00:00
hw_breakpoint.c arm64: Fix missing #include in hw_breakpoint.c 2015-10-12 12:10:53 +01:00
hyp-stub.S
image.h arm64/efi: Make strnlen() available to the EFI namespace 2016-02-16 10:32:10 +00:00
insn.c arm64: insn: remove BUG_ON from codegen 2016-01-17 19:15:26 -05:00
io.c
irq.c arm64: remove irq_count and do_softirq_own_stack() 2015-12-21 17:26:01 +00:00
jump_label.c jump_label: Rename JUMP_LABEL_{EN,DIS}ABLE to JUMP_LABEL_{JMP,NOP} 2015-08-03 11:34:12 +02:00
kgdb.c arm64/debug: Simplify BRK insn opcode declarations 2015-07-27 11:08:42 +01:00
kuser32.S
Makefile xen: features and fixes for 4.5-rc0 2016-01-12 13:05:36 -08:00
module.c arm64: module: avoid undefined shift behavior in reloc_data() 2016-01-05 11:27:20 +00:00
paravirt.c arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops 2015-12-21 14:40:54 +00:00
pci.c ARM64: PCI: do not enable resources on PROBE_ONLY systems 2015-07-30 20:17:07 +01:00
perf_callchain.c arm64: ftrace: fix a stack tracer's output under function graph tracer 2015-12-21 17:26:02 +00:00
perf_event.c arm64: perf: add support for Cortex-A72 2015-12-22 14:45:35 +00:00
perf_regs.c perf: Move task_pt_regs sampling into arch code 2015-01-09 11:12:28 +01:00
process.c arm64: ftrace: fix a stack tracer's output under function graph tracer 2015-12-21 17:26:02 +00:00
psci.c drivers: firmware: psci: move power_state handling to generic code 2015-10-02 14:35:16 +01:00
ptrace.c arm64: Clear out any singlestep state on a ptrace detach operation 2015-12-07 17:48:21 +00:00
return_address.c arm64: ftrace: fix a stack tracer's output under function graph tracer 2015-12-21 17:26:02 +00:00
setup.c arm64 updates for 4.4: 2015-11-04 14:47:13 -08:00
signal32.c arm64: compat: fix vfp save/restore across signal handlers in big-endian 2015-09-17 11:57:03 +01:00
signal.c arm64: Removed unused variable 2015-04-13 20:40:10 +02:00
sleep.S arm64: kasan: clear stale stack poison 2016-03-09 15:43:42 -08:00
smccc-call.S ARM: 8480/2: arm64: add implementation for arm-smccc 2016-01-04 16:24:45 +00:00
smp_spin_table.c ARM64: kernel: make cpu_ops hooks DT agnostic 2015-05-19 16:09:29 +01:00
smp.c arm64: smp: make of_parse_and_init_cpus static 2015-11-12 15:18:14 +00:00
stacktrace.c arm64: make irq_stack_ptr more robust 2016-02-12 15:53:51 +00:00
suspend.c arm64: kernel: pause/unpause function graph tracer in cpu_suspend() 2015-11-17 17:11:45 +00:00
sys32.c arm64: fix implementation of mmap2 compat syscall 2015-03-19 10:43:51 +00:00
sys_compat.c
sys.c arm64: make sys_call_table const 2015-01-27 09:38:08 +00:00
time.c arm64: ftrace: fix a stack tracer's output under function graph tracer 2015-12-21 17:26:02 +00:00
topology.c arm64: kernel: remove non-legit DT warnings when booting using ACPI 2015-07-27 11:08:41 +01:00
trace-events-emulation.h
traps.c arm64: make irq_stack_ptr more robust 2016-02-12 15:53:51 +00:00
vdso.c arm64: VDSO: fix coarse clock monotonicity regression 2015-08-10 15:37:45 +01:00
vmlinux.lds.S arm64 updates for 4.5: 2016-01-12 12:23:33 -08:00