linux_dsm_epyc7002/arch/x86
Nick Desaulniers 428b8f1d9f KVM: VMX: don't allow memory operands for inline asm that modifies SP
THUNK_TARGET defines [thunk_target] as having "rm" input constraints
when CONFIG_RETPOLINE is not set, which isn't constrained enough for
this specific case.

For inline assembly that modifies the stack pointer before using this
input, the underspecification of constraints is dangerous, and results
in an indirect call to a previously pushed flags register.

In this case `entry`'s stack slot is good enough to satisfy the "m"
constraint in "rm", but the inline assembly in
handle_external_interrupt_irqoff() modifies the stack pointer via
push+pushf before using this input, which in this case results in
calling what was the previous state of the flags register, rather than
`entry`.

Be more specific in the constraints by requiring `entry` be in a
register, and not a memory operand.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: syzbot+3f29ca2efb056a761e38@syzkaller.appspotmail.com
Debugged-by: Alexander Potapenko <glider@google.com>
Debugged-by: Paolo Bonzini <pbonzini@redhat.com>
Debugged-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Message-Id: <20200323191243.30002-1-ndesaulniers@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-23 15:40:51 -04:00
..
boot Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
configs x86: Remove the calgary IOMMU driver 2019-11-15 10:36:59 +01:00
crypto crypto: x86/poly1305 - emit does base conversion itself 2020-01-22 16:21:11 +08:00
entry kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
events Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-01-28 09:44:15 -08:00
hyperv x86/hyperv: Suspend/resume the hypercall page for hibernation 2020-02-01 09:41:16 +01:00
ia32 x86: Remove force_iret() 2020-01-08 19:40:51 +01:00
include KVM: x86: remove stale comment from struct x86_emulate_ctxt 2020-03-03 17:38:22 +01:00
kernel KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis 2020-02-28 10:34:25 +01:00
kvm KVM: VMX: don't allow memory operands for inline asm that modifies SP 2020-03-23 15:40:51 -04:00
lib Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-01-31 11:05:33 -08:00
math-emu Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 10:42:40 -08:00
mm x86: mm: avoid allocating struct mm_struct on the stack 2020-02-04 03:05:25 +00:00
net bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS 2020-01-09 08:46:18 -08:00
oprofile x86: Use pr_warn instead of pr_warning 2019-10-18 15:00:18 +02:00
pci pci-v5.6-changes 2020-01-31 14:48:54 -08:00
platform A single fix for a EFI boot regression on X86 which was caused by the 2020-02-09 11:54:50 -08:00
power x86/asm/32: Change all ENTRY+ENDPROC to SYM_FUNC_* 2019-10-18 12:03:43 +02:00
purgatory Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 10:42:40 -08:00
ras RAS/CEC: Add CONFIG_RAS_CEC_DEBUG and move CEC debug features there 2019-06-08 17:39:24 +02:00
realmode kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
tools kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
um um: Implement copy_thread_tls 2020-01-07 13:31:29 +01:00
video treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
xen A set of fixes for X86: 2020-02-09 12:11:12 -08:00
.gitignore x86/build: Add arch/x86/tools/insn_decoder_test to .gitignore 2018-02-13 14:10:29 +01:00
Kbuild treewide: Add SPDX license identifier - Kbuild 2019-05-30 11:32:33 -07:00
Kconfig asm-generic/tlb: rename HAVE_RCU_TABLE_FREE 2020-02-04 03:05:26 +00:00
Kconfig.cpu x86/cpu: Detect VMX features on Intel, Centaur and Zhaoxin CPUs 2020-01-13 18:02:53 +01:00
Kconfig.debug x86: mm: convert dump_pagetables to use walk_page_range 2020-02-04 03:05:25 +00:00
Makefile x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning 2019-08-28 17:31:31 +02:00
Makefile_32.cpu x86/math-emu: Limit MATH_EMULATION to 486SX compatibles 2019-10-03 10:51:17 +02:00
Makefile.um x86, powerpc: Remove -funit-at-a-time compiler option entirely 2018-12-09 11:55:32 +01:00