Fix arm64 kvm priv escalation (rhbz 1635475 1635476)
This commit is contained in:
parent
d54a013326
commit
5826936f37
|
@ -0,0 +1,155 @@
|
|||
From d26c25a9d19b5976b319af528886f89cf455692d Mon Sep 17 00:00:00 2001
|
||||
From: Dave Martin <Dave.Martin@arm.com>
|
||||
Date: Thu, 27 Sep 2018 16:53:21 +0100
|
||||
Subject: arm64: KVM: Tighten guest core register access from userspace
|
||||
|
||||
From: Dave Martin <Dave.Martin@arm.com>
|
||||
|
||||
commit d26c25a9d19b5976b319af528886f89cf455692d upstream.
|
||||
|
||||
We currently allow userspace to access the core register file
|
||||
in about any possible way, including straddling multiple
|
||||
registers and doing unaligned accesses.
|
||||
|
||||
This is not the expected use of the ABI, and nobody is actually
|
||||
using it that way. Let's tighten it by explicitly checking
|
||||
the size and alignment for each field of the register file.
|
||||
|
||||
Cc: <stable@vger.kernel.org>
|
||||
Fixes: 2f4a07c5f9fe ("arm64: KVM: guest one-reg interface")
|
||||
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
|
||||
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
|
||||
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
|
||||
[maz: rewrote Dave's initial patch to be more easily backported]
|
||||
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
|
||||
Signed-off-by: Will Deacon <will.deacon@arm.com>
|
||||
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
||||
|
||||
---
|
||||
arch/arm64/kvm/guest.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
|
||||
1 file changed, 45 insertions(+)
|
||||
|
||||
--- a/arch/arm64/kvm/guest.c
|
||||
+++ b/arch/arm64/kvm/guest.c
|
||||
@@ -57,6 +57,45 @@ static u64 core_reg_offset_from_id(u64 i
|
||||
return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
|
||||
}
|
||||
|
||||
+static int validate_core_offset(const struct kvm_one_reg *reg)
|
||||
+{
|
||||
+ u64 off = core_reg_offset_from_id(reg->id);
|
||||
+ int size;
|
||||
+
|
||||
+ switch (off) {
|
||||
+ case KVM_REG_ARM_CORE_REG(regs.regs[0]) ...
|
||||
+ KVM_REG_ARM_CORE_REG(regs.regs[30]):
|
||||
+ case KVM_REG_ARM_CORE_REG(regs.sp):
|
||||
+ case KVM_REG_ARM_CORE_REG(regs.pc):
|
||||
+ case KVM_REG_ARM_CORE_REG(regs.pstate):
|
||||
+ case KVM_REG_ARM_CORE_REG(sp_el1):
|
||||
+ case KVM_REG_ARM_CORE_REG(elr_el1):
|
||||
+ case KVM_REG_ARM_CORE_REG(spsr[0]) ...
|
||||
+ KVM_REG_ARM_CORE_REG(spsr[KVM_NR_SPSR - 1]):
|
||||
+ size = sizeof(__u64);
|
||||
+ break;
|
||||
+
|
||||
+ case KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]) ...
|
||||
+ KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
|
||||
+ size = sizeof(__uint128_t);
|
||||
+ break;
|
||||
+
|
||||
+ case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
|
||||
+ case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
|
||||
+ size = sizeof(__u32);
|
||||
+ break;
|
||||
+
|
||||
+ default:
|
||||
+ return -EINVAL;
|
||||
+ }
|
||||
+
|
||||
+ if (KVM_REG_SIZE(reg->id) == size &&
|
||||
+ IS_ALIGNED(off, size / sizeof(__u32)))
|
||||
+ return 0;
|
||||
+
|
||||
+ return -EINVAL;
|
||||
+}
|
||||
+
|
||||
static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
|
||||
{
|
||||
/*
|
||||
@@ -76,6 +115,9 @@ static int get_core_reg(struct kvm_vcpu
|
||||
(off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
|
||||
return -ENOENT;
|
||||
|
||||
+ if (validate_core_offset(reg))
|
||||
+ return -EINVAL;
|
||||
+
|
||||
if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
|
||||
return -EFAULT;
|
||||
|
||||
@@ -98,6 +140,9 @@ static int set_core_reg(struct kvm_vcpu
|
||||
(off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
|
||||
return -ENOENT;
|
||||
|
||||
+ if (validate_core_offset(reg))
|
||||
+ return -EINVAL;
|
||||
+
|
||||
if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
|
||||
return -EINVAL;
|
||||
|
||||
From 2a3f93459d689d990b3ecfbe782fec89b97d3279 Mon Sep 17 00:00:00 2001
|
||||
From: Marc Zyngier <marc.zyngier@arm.com>
|
||||
Date: Thu, 27 Sep 2018 16:53:22 +0100
|
||||
Subject: arm64: KVM: Sanitize PSTATE.M when being set from userspace
|
||||
|
||||
From: Marc Zyngier <marc.zyngier@arm.com>
|
||||
|
||||
commit 2a3f93459d689d990b3ecfbe782fec89b97d3279 upstream.
|
||||
|
||||
Not all execution modes are valid for a guest, and some of them
|
||||
depend on what the HW actually supports. Let's verify that what
|
||||
userspace provides is compatible with both the VM settings and
|
||||
the HW capabilities.
|
||||
|
||||
Cc: <stable@vger.kernel.org>
|
||||
Fixes: 0d854a60b1d7 ("arm64: KVM: enable initialization of a 32bit vcpu")
|
||||
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
|
||||
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
|
||||
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
|
||||
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
|
||||
Signed-off-by: Will Deacon <will.deacon@arm.com>
|
||||
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
||||
|
||||
---
|
||||
arch/arm64/kvm/guest.c | 10 +++++++++-
|
||||
1 file changed, 9 insertions(+), 1 deletion(-)
|
||||
|
||||
--- a/arch/arm64/kvm/guest.c
|
||||
+++ b/arch/arm64/kvm/guest.c
|
||||
@@ -152,17 +152,25 @@ static int set_core_reg(struct kvm_vcpu
|
||||
}
|
||||
|
||||
if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
|
||||
- u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
|
||||
+ u64 mode = (*(u64 *)valp) & COMPAT_PSR_MODE_MASK;
|
||||
switch (mode) {
|
||||
case COMPAT_PSR_MODE_USR:
|
||||
+ if (!system_supports_32bit_el0())
|
||||
+ return -EINVAL;
|
||||
+ break;
|
||||
case COMPAT_PSR_MODE_FIQ:
|
||||
case COMPAT_PSR_MODE_IRQ:
|
||||
case COMPAT_PSR_MODE_SVC:
|
||||
case COMPAT_PSR_MODE_ABT:
|
||||
case COMPAT_PSR_MODE_UND:
|
||||
+ if (!vcpu_el1_is_32bit(vcpu))
|
||||
+ return -EINVAL;
|
||||
+ break;
|
||||
case PSR_MODE_EL0t:
|
||||
case PSR_MODE_EL1t:
|
||||
case PSR_MODE_EL1h:
|
||||
+ if (vcpu_el1_is_32bit(vcpu))
|
||||
+ return -EINVAL;
|
||||
break;
|
||||
default:
|
||||
err = -EINVAL;
|
|
@ -630,6 +630,9 @@ Patch509: powerpc-ipv6.patch
|
|||
# rhbz 1634250
|
||||
Patch510: HID-intel-ish-hid-Enable-Sunrise-Point-H-ish-driver.patch
|
||||
|
||||
# rhbz 1635475 1635476
|
||||
Patch511: arm64_kvm_security.patch
|
||||
|
||||
# END OF PATCH DEFINITIONS
|
||||
|
||||
%endif
|
||||
|
@ -1879,6 +1882,9 @@ fi
|
|||
#
|
||||
#
|
||||
%changelog
|
||||
* Wed Oct 03 2018 Justin M. Forbes <jforbes@fedoraproject.org>
|
||||
- Fix arm64 kvm priv escalation (rhbz 1635475 1635476)
|
||||
|
||||
* Mon Oct 01 2018 Laura Abbott <labbott@redhat.com>
|
||||
- Disable CONFIG_CRYPTO_DEV_SP_PSP (rhbz 1608242)
|
||||
|
||||
|
|
Loading…
Reference in New Issue