Chang S. Bae 74569cb9ed x86/signal: Detect and prevent an alternate signal stack overflow ... [ Upstream commit 2beb4a53fc3f1081cedc1c1a198c7f56cc4fc60c ] The kernel pushes context on to the userspace stack to prepare for the user's signal handler. When the user has supplied an alternate signal stack, via sigaltstack(2), it is easy for the kernel to verify that the stack size is sufficient for the current hardware context. Check if writing the hardware context to the alternate stack will exceed it's size. If yes, then instead of corrupting user-data and proceeding with the original signal handler, an immediate SIGSEGV signal is delivered. Refactor the stack pointer check code from on_sig_stack() and use the new helper. While the kernel allows new source code to discover and use a sufficient alternate signal stack size, this check is still necessary to protect binaries with insufficient alternate signal stack size from data corruption. Fixes: c2bc11f10a ("x86, AVX-512: Enable AVX-512 States Context Switch") Reported-by: Florian Weimer <fweimer@redhat.com> Suggested-by: Jann Horn <jannh@google.com> Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Len Brown <len.brown@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20210518200320.17239-6-chang.seok.bae@intel.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=153531 Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-07-20 16:05:50 +02:00
..
boot	x86/boot/compressed/64: Check SEV encryption in the 32-bit boot-path	2021-05-26 12:06:57 +02:00
configs
crypto	crypto: x86/curve25519 - fix cpu feature checking logic in mod_exit	2021-07-14 16:56:06 +02:00
entry	x86/sev: Split up runtime #VC handler for correct state tracking	2021-07-14 16:56:09 +02:00
events	perf/x86: Track pmu in per-CPU cpu_hw_events	2021-06-30 08:47:24 -04:00
hyperv
ia32
include	x86/fpu: Return proper error codes from user access functions	2021-07-20 16:05:48 +02:00
kernel	x86/signal: Detect and prevent an alternate signal stack overflow	2021-07-20 16:05:50 +02:00
kvm	KVM: X86: Disable hardware breakpoints unconditionally before kvm_x86->run()	2021-07-20 16:05:36 +02:00
lib	x86/msr: Fix wr/rdmsr_safe_regs_on_cpu() prototypes	2021-05-22 11:40:51 +02:00
math-emu
mm	x86/ioremap: Map EFI-reserved memory as encrypted for SEV	2021-06-23 14:42:52 +02:00
net	bpf, x86: Validate computation of branch displacements for x86-32	2021-04-10 13:36:11 +02:00
oprofile
pci	PCI: Add AMD RS690 quirk to enable 64-bit DMA	2021-06-30 08:47:23 -04:00
platform
power	PM: hibernate: x86: Use crc32 instead of md5 for hibernation e820 integrity check	2021-05-14 09:50:21 +02:00
purgatory
ras
realmode
tools
um
video
xen	x86/xen: Fix noinstr fail in exc_xen_unknown_trap()	2021-06-30 08:47:18 -04:00
.gitignore
Kbuild
Kconfig	x86/platform/uv: Fix !KEXEC build failure	2021-05-14 09:50:20 +02:00
Kconfig.assembler
Kconfig.cpu
Kconfig.debug
Makefile	x86/build: Propagate $(CLANG_FLAGS) to $(REALMODE_FLAGS)	2021-05-11 14:47:18 +02:00
Makefile_32.cpu
Makefile.um