Thomas Gleixner 59f5ede3bc x86/fpu: Prevent FPU state corruption ... The FPU usage related to task FPU management is either protected by disabling interrupts (switch_to, return to user) or via fpregs_lock() which is a wrapper around local_bh_disable(). When kernel code wants to use the FPU then it has to check whether it is possible by calling irq_fpu_usable(). But the condition in irq_fpu_usable() is wrong. It allows FPU to be used when: !in_interrupt() || interrupted_user_mode() || interrupted_kernel_fpu_idle() The latter is checking whether some other context already uses FPU in the kernel, but if that's not the case then it allows FPU to be used unconditionally even if the calling context interrupted a fpregs_lock() critical region. If that happens then the FPU state of the interrupted context becomes corrupted. Allow in kernel FPU usage only when no other context has in kernel FPU usage and either the calling context is not hard interrupt context or the hard interrupt did not interrupt a local bottomhalf disabled region. It's hard to find a proper Fixes tag as the condition was broken in one way or the other for a very long time and the eager/lazy FPU changes caused a lot of churn. Picked something remotely connected from the history. This survived undetected for quite some time as FPU usage in interrupt context is rare, but the recent changes to the random code unearthed it at least on a kernel which had FPU debugging enabled. There is probably a higher rate of silent corruption as not all issues can be detected by the FPU debugging code. This will be addressed in a subsequent change. Fixes: 5d2bd7009f ("x86, fpu: decouple non-lazy/eager fpu restore from xsave") Reported-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220501193102.588689270@linutronix.de		2022-05-05 02:40:19 +02:00
..
acpi	Power management updates for 5.18-rc1	2022-03-21 14:26:28 -07:00
apic	bitmap patches for 5.17-rc1	2022-01-23 06:20:44 +02:00
cpu	x86/cpu: Load microcode during restore_processor_state()	2022-04-19 19:37:05 +02:00
fpu	x86/fpu: Prevent FPU state corruption	2022-05-05 02:40:19 +02:00
kprobes	x86,kprobes: Fix optprobe trampoline to generate complete pt_regs	2022-03-28 19:38:51 -07:00
.gitignore
alternative.c	Add support for Intel CET-IBT, available since Tigerlake (11th gen), which is a	2022-03-27 10:17:23 -07:00
amd_gart_64.c	x86/amd_gart: don't set failed sg dma_address to DMA_MAPPING_ERROR	2021-08-09 17:13:06 +02:00
amd_nb.c	hwmon updates for v5.17	2022-01-11 10:25:36 -08:00
aperture_64.c	proc/vmcore: convert oldmem_pfn_is_ram callback to more generic vmcore callbacks	2021-11-09 10:02:48 -08:00
apm_32.c	x86/ibt: Disable IBT around firmware	2022-03-15 10:32:40 +01:00
asm-offsets.c	um, x86: bury crypto_tfm_ctx_offset	2021-12-21 21:31:35 +01:00
asm-offsets_32.c
asm-offsets_64.c
audit_64.c	audit: add support for the openat2 syscall	2021-10-01 16:52:48 -04:00
bootflag.c
check.c
cpuid.c
crash.c	x86/crash: Remove crash_reserve_low_1M()	2021-06-07 12:14:45 +02:00
crash_core_32.c
crash_core_64.c
crash_dump_32.c
crash_dump_64.c	mm/vmalloc: fix spinning drain_vmap_work after reading from /proc/vmcore	2022-04-15 14:49:56 -07:00
devicetree.c	Devicetree updates for v5.16:	2021-11-02 22:22:13 -07:00
doublefault_32.c	exit/doublefault: Remove apparently bogus comment about rewind_stack_do_exit	2021-10-20 13:09:43 -05:00
dumpstack.c	x86: remove __range_not_ok()	2022-02-25 09:36:05 +01:00
dumpstack_32.c
dumpstack_64.c	x86/mm/64: Improve stack overflow warnings	2021-09-21 13:57:43 +02:00
e820.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-09 12:49:44 +01:00
early-quirks.c	Merge drm/drm-next into drm-intel-next	2022-01-31 13:19:33 -05:00
early_printk.c	usb: early: xhci-dbc: Remove duplicate keep parsing	2022-03-15 18:20:34 +01:00
ebda.c
eisa.c
espfix_64.c
ftrace.c	x86/ibt,ftrace: Make function-graph play nice	2022-03-15 10:32:37 +01:00
ftrace_32.S	x86: Prepare asm files for straight-line-speculation	2021-12-08 12:25:37 +01:00
ftrace_64.S	x86/ibt,ftrace: Annotate ftrace code patching	2022-03-15 10:32:41 +01:00
head32.c
head64.c	x86/head64: Add missing __head annotation to sme_postprocess_startup()	2022-02-12 11:37:09 +01:00
head_32.S	x86: Prepare asm files for straight-line-speculation	2021-12-08 12:25:37 +01:00
head_64.S	x86/ibt,sev: Annotations	2022-03-15 10:32:41 +01:00
hpet.c	rtc: Check return value from mc146818_get_time()	2021-12-16 21:50:06 +01:00
hw_breakpoint.c
i8237.c
i8253.c
i8259.c	x86: Avoid magic number with ELCR register accesses	2021-08-10 23:31:43 +02:00
idt.c	x86/ibt: Add IBT feature, MSR and #CP handling	2022-03-15 10:32:39 +01:00
io_delay.c
ioport.c
irq.c	x86/irq: Ensure PI wakeup handler is unregistered before module unload	2021-10-22 12:45:35 -04:00
irq_32.c	x86/softirq: Disable softirq stacks on PREEMPT_RT	2021-09-27 12:28:32 +02:00
irq_64.c
irq_work.c
irqflags.S	x86: Prepare asm files for straight-line-speculation	2021-12-08 12:25:37 +01:00
irqinit.c
itmt.c	x86/sched: Decrease further the priorities of SMT siblings	2021-10-05 15:51:59 +02:00
jailhouse.c
jump_label.c	jump_labels: Mark __jump_label_transform() as __always_inlined to work around aggressive compiler un-inlining	2021-07-13 06:32:05 +02:00
kdebugfs.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-09 12:49:44 +01:00
kexec-bzimage64.c
kgdb.c
ksysfs.c	x86/boot: Fix memremap of setup_indirect structures	2022-03-09 12:49:44 +01:00
kvm.c	x86/kvm: Preserve BSP MSR_KVM_POLL_CONTROL across suspend/resume	2022-04-21 13:16:14 -04:00
kvmclock.c	x86/kvmclock: Fix Hyper-V Isolated VM's boot issue when vCPUs > 64	2022-02-25 10:09:34 -05:00
ldt.c	memcg: enable accounting for ldt_struct objects	2021-09-03 09:58:13 -07:00
machine_kexec_32.c	x86/kexec: Set_[gi]dt() -> native_[gi]dt_invalidate() in machine_kexec_*.c	2021-05-21 12:36:45 +02:00
machine_kexec_64.c	x86/ibt,kexec: Disable CET on kexec	2022-03-15 10:32:39 +01:00
Makefile	x86,rethook,kprobes: Replace kretprobe with rethook on x86	2022-03-28 19:38:51 -07:00
mmconf-fam10h_64.c	x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG	2021-05-10 07:51:38 +02:00
module.c	Add support for Intel CET-IBT, available since Tigerlake (11th gen), which is a	2022-03-27 10:17:23 -07:00
mpparse.c	x86: Avoid magic number with ELCR register accesses	2021-08-10 23:31:43 +02:00
msr.c
nmi.c	x86/nmi: Remove the 'strange power saving mode' hint from unknown NMI handler	2022-03-16 11:02:41 +01:00
nmi_selftest.c
paravirt-spinlocks.c
paravirt.c	x86/ibt,paravirt: Sprinkle ENDBR	2022-03-15 10:32:36 +01:00
pci-dma.c
pci-iommu_table.c
pci-swiotlb.c	x86/sme: Replace occurrences of sme_active() with cc_platform_has()	2021-10-04 11:46:46 +02:00
pcspeaker.c
perf_regs.c
platform-quirks.c
pmem.c
probe_roms.c	x86/pci/probe_roms: Use to_pci_driver() instead of pci_dev->driver	2021-10-18 09:20:15 -05:00
process.c	Merge branch 'x86/cpu' into x86/core, to resolve conflicts	2022-03-15 12:52:51 +01:00
process.h	x86: Snapshot thread flags	2021-12-01 00:06:43 +01:00
process_32.c	x86/fpu: Move context switch and exit to user inlines into sched.h	2021-10-20 15:27:27 +02:00
process_64.c	x86: Remove toolchain check for X32 ABI capability	2022-03-15 10:32:48 +01:00
ptrace.c	ptrace: Cleanups for v5.18	2022-03-28 17:29:53 -07:00
pvclock.c
quirks.c
reboot.c	x86/mm: Flush global TLB when switching to trampoline page-table	2021-12-06 09:54:10 +01:00
reboot_fixups_32.c
relocate_kernel_32.S	x86: Prepare asm files for straight-line-speculation	2021-12-08 12:25:37 +01:00
relocate_kernel_64.S	x86/ibt: Annotate text references	2022-03-15 10:32:40 +01:00
resource.c	x86/PCI: revert "Ignore E820 reservations for bridge windows on newer systems"	2022-02-09 19:42:58 +01:00
rethook.c	x86,rethook: Fix arch_rethook_trampoline() to generate a complete pt_regs	2022-03-28 19:38:51 -07:00
rtc.c
setup.c	x86/setup: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef	2022-03-23 19:00:34 -07:00
setup_percpu.c	mm: percpu: add generic pcpu_populate_pte() function	2022-01-20 08:52:52 +02:00
sev-shared.c	x86/sev: Shorten GHCB terminate macro names	2021-11-15 20:31:16 +01:00
sev.c	- Add support for decoding instructions which do MMIO accesses in order	2022-01-10 10:00:03 -08:00
sev_verify_cbit.S	x86: Prepare asm files for straight-line-speculation	2021-12-08 12:25:37 +01:00
signal.c	tracehook: Remove tracehook.h	2022-03-10 16:51:51 -06:00
signal_compat.c	signal: Verify the alignment and size of siginfo_t	2021-07-23 13:15:31 -05:00
smp.c
smpboot.c	x86/ACPI: CPPC: Move init_freq_invariance_cppc() into x86 CPPC	2022-03-08 19:16:43 +01:00
stacktrace.c	x86: remove __range_not_ok()	2022-02-25 09:36:05 +01:00
static_call.c	x86,static_call: Fix __static_call_return0 for i386	2022-04-05 09:59:37 +02:00
step.c
sys_ia32.c
sys_x86_64.c
tboot.c
time.c
tls.c
tls.h
topology.c	drivers/base/node: consolidate node device subsystem initialization in node_dev_init()	2022-03-22 15:57:10 -07:00
trace.c	trace/osnoise: Fix an ifdef comment	2021-10-25 23:02:36 -04:00
trace_clock.c
tracepoint.c
traps.c	Reenable ENQCMD/PASID support:	2022-03-21 12:28:13 -07:00
tsc.c	x86/tsc: Be consistent about use_tsc_delay()	2022-03-15 18:20:33 +01:00
tsc_msr.c
tsc_sync.c	x86/tsc: Add a timer to make sure TSC_adjust is always checked	2021-12-02 00:40:35 +01:00
umip.c	x86/umip: Downgrade warning messages to debug loglevel	2021-09-25 13:23:28 +02:00
unwind_frame.c	x86/unwind: Recover kretprobe trampoline entry	2021-09-30 21:24:07 -04:00
unwind_guess.c	x86/unwind: Recover kretprobe trampoline entry	2021-09-30 21:24:07 -04:00
unwind_orc.c	x86/unwind/orc: Recheck address range after stack info was updated	2022-04-19 21:58:46 +02:00
uprobes.c
verify_cpu.S	x86: Prepare asm files for straight-line-speculation	2021-12-08 12:25:37 +01:00
vm86_32.c	signal: Replace force_fatal_sig with force_exit_sig when in doubt	2021-11-19 09:15:58 -06:00
vmlinux.lds.S	objtool: Find unused ENDBR instructions	2022-03-15 10:32:47 +01:00
vsmp_64.c
x86_init.c	x86/mm/cpa: Generalize __set_memory_enc_pgtable()	2022-02-23 19:14:29 +01:00