Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-02 17:11:33 +00:00
Code Issues Packages Projects Releases Wiki Activity
04949ccc27
linux/arch/arm64/kernel
History
Masami Hiramatsu b3980e4852 arm64: kprobes: Recover pstate.D in single-step exception handler 
kprobes manipulates the interrupted PSTATE for single step, and
doesn't restore it. Thus, if we put a kprobe where the pstate.D
(debug) masked, the mask will be cleared after the kprobe hits.

Moreover, in the most complicated case, this can lead a kernel
crash with below message when a nested kprobe hits.

[  152.118921] Unexpected kernel single-step exception at EL1

When the 1st kprobe hits, do_debug_exception() will be called.
At this point, debug exception (= pstate.D) must be masked (=1).
But if another kprobes hits before single-step of the first kprobe
(e.g. inside user pre_handler), it unmask the debug exception
(pstate.D = 0) and return.
Then, when the 1st kprobe setting up single-step, it saves current
DAIF, mask DAIF, enable single-step, and restore DAIF.
However, since "D" flag in DAIF is cleared by the 2nd kprobe, the
single-step exception happens soon after restoring DAIF.

This has been introduced by commit 7419333fa1 ("arm64: kprobe:
Always clear pstate.D in breakpoint exception handler")

To solve this issue, this stores all DAIF bits and restore it
after single stepping.

Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 7419333fa1 ("arm64: kprobe: Always clear pstate.D in breakpoint exception handler")
Reviewed-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-02 11:55:50 +01:00
..
probes arm64: kprobes: Recover pstate.D in single-step exception handler 2019-08-02 11:55:50 +01:00
vdso arm64: vdso: Cleanup Makefiles 2019-07-22 10:37:33 +01:00
vdso32 arm64: vdso: Cleanup Makefiles 2019-07-22 10:37:33 +01:00
.gitignore
acpi_numa.c acpi: Create subtable parsing infrastructure 2019-04-04 18:41:12 +02:00
acpi_parking_protocol.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
acpi.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
alternative.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
armv8_deprecated.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
asm-offsets.c arm64: vdso: Remove unnecessary asm-offsets.c definitions 2019-06-26 07:28:10 +02:00
cacheinfo.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
cpu_errata.c arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests 2019-07-05 13:56:27 +01:00
cpu_ops.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
cpu-reset.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpu-reset.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufeature.c arm64: cpufeature: Fix feature comparison for CTR_EL0.{CWG,ERG} 2019-07-31 18:10:55 +01:00
cpuidle.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpuinfo.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
crash_core.c arm64: kernel: arch_crash_save_vmcoreinfo() should depend on CONFIG_CRASH_CORE 2018-09-11 11:08:49 +01:00
crash_dump.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
debug-monitors.c arm64: Remove unneeded rcu_read_lock from debug handlers 2019-08-01 15:00:27 +01:00
efi-entry.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
efi-header.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
efi-rt-wrapper.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
efi.c mm/pgtable: drop pgtable_t variable from pte_fn_t functions 2019-07-12 11:05:46 -07:00
entry-fpsimd.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
entry-ftrace.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
entry.S arm64: entry: SP Alignment Fault doesn't write to FAR_EL1 2019-07-22 16:22:34 +01:00
fpsimd.c arm64/sve: Fix a couple of magic numbers for the Z-reg count 2019-07-22 11:49:03 +01:00
ftrace.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
head.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
hibernate-asm.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
hibernate.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
hw_breakpoint.c arm64: hw_breakpoint: Fix warnings about implicit fallthrough 2019-07-29 11:59:15 +01:00
hyp-stub.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
image.h arm64 fixes for 5.2 2019-07-03 15:57:30 +08:00
insn.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
io.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
irq.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
jump_label.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
kaslr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
kexec_image.c docs: arm64: convert docs to ReST and rename to .rst 2019-06-14 14:20:27 -06:00
kgdb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
kuser32.S docs: arm: convert docs to ReST and rename to *.rst 2019-07-15 09:20:24 -03:00
machine_kexec_file.c arm64: kexec_file: handle empty command-line 2019-02-05 09:34:49 +00:00
machine_kexec.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
Makefile arm64: vdso: Enable vDSO compat support 2019-06-22 21:21:09 +02:00
module-plts.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
module.c arm64: module: Mark expected switch fall-through 2019-07-29 11:59:36 +01:00
module.lds arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
paravirt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
pci.c pci-v5.3-changes 2019-07-15 20:44:49 -07:00
perf_callchain.c arm64: stacktrace: Factor out backtrace initialisation 2019-07-22 11:44:08 +01:00
perf_event.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
perf_regs.c compat: Move compat_timespec/ timeval to compat_time.h 2018-04-19 13:29:54 +02:00
pointer_auth.c arm64: ptr auth: Move per-thread keys from thread_info to thread_struct 2018-12-13 16:42:47 +00:00
process.c arm64: Force SSBS on context switch 2019-07-22 15:24:16 +01:00
psci.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
ptrace.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
reloc_test_core.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
reloc_test_syms.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
relocate_kernel.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
return_address.c arm64: unwind: Prohibit probing on return_address() 2019-08-01 15:00:26 +01:00
sdei.c arm64: fix wrong check of on_sdei_stack in nmi context 2019-04-04 16:02:25 +01:00
setup.c arm64: move jump_label_init() before parse_early_param() 2019-07-12 11:05:46 -07:00
signal32.c arm64: compat: Get sigreturn trampolines from vDSO 2019-06-22 21:21:09 +02:00
signal.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
sigreturn32.S arm64: compat: Split kuser32 2019-04-23 18:01:57 +01:00
sleep.S arm64: kernel: use aff3 instead of aff2 in comment 2019-06-04 14:51:01 +01:00
smccc-call.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
smp_spin_table.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
smp.c arm64: smp: Mark expected switch fall-through 2019-07-29 11:59:30 +01:00
ssbd.c arm64: ssbd: explicitly depend on <linux/prctl.h> 2019-06-17 18:38:10 +01:00
stacktrace.c arm64: unwind: Prohibit probing on return_address() 2019-08-01 15:00:26 +01:00
suspend.c arm64: mm: Support Common Not Private translations 2018-09-18 12:02:27 +01:00
sys32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 452 2019-06-19 17:09:08 +02:00
sys_compat.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
sys.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
syscall.c arm64: errata: Add workaround for Cortex-A76 erratum #1463225 2019-05-23 11:38:10 +01:00
time.c arm64: stacktrace: Factor out backtrace initialisation 2019-07-22 11:44:08 +01:00
topology.c arm64: topology: re-introduce numa mask check for scheduler MC selection 2018-07-06 13:18:18 +01:00
trace-events-emulation.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
traps.c arm64: stacktrace: Factor out backtrace initialisation 2019-07-22 11:44:08 +01:00
vdso.c arm64: compat: VDSO setup for compat layer 2019-06-22 21:21:08 +02:00
vmlinux.lds.S arm64: relocatable: fix inconsistencies in linker script and options 2018-12-04 12:48:25 +00:00