CVE-2016-5412 powerpc: kvm: Infinite loop in HV mode (rhbz 1349916 1361040)
This commit is contained in:
Josh Boyer
parent
fa6164d56e
commit
7178b87593
@ -637,6 +637,10 @@ Patch839: Revert-ALSA-hda-remove-controller-dependency-on-i915.patch
|
||||
#CVE-2016-6136 rhbz 1353533 1353534
|
||||
Patch841: audit-fix-a-double-fetch-in-audit_log_single_execve_arg.patch
|
||||
|
||||
#CVE-2016-5412 rhbz 1349916 1361040
|
||||
Patch842: kvm-ppc-Book3S-HV-Pull-out-TM-state-save.patch
|
||||
Patch843: kvm-ppc-Book3S-HV-Save-restore-TM-state.patch
|
||||
|
||||
# END OF PATCH DEFINITIONS
|
||||
|
||||
%endif
|
||||
@ -2171,6 +2175,9 @@ fi
|
||||
#
|
||||
#
|
||||
%changelog
|
||||
* Thu Jul 28 2016 Josh Boyer <jwboyer@fedoraproject.org>
|
||||
- CVE-2016-5412 powerpc: kvm: Infinite loop in HV mode (rhbz 1349916 1361040)
|
||||
|
||||
* Thu Jul 28 2016 Peter Robinson <pbrobinson@fedoraproject.org> 4.8.0-0.rc0.git1.1
|
||||
- Filter nvme rdma modules to extras
|
||||
- Fix IP Wireless driver filtering (rhbz 1356043) thanks lkundrak
|
||||
|
||||
506
kvm-ppc-Book3S-HV-Pull-out-TM-state-save.patch
Normal file
506
kvm-ppc-Book3S-HV-Pull-out-TM-state-save.patch
Normal file
@ -0,0 +1,506 @@
|
||||
Subject: [PATCH 1/2] KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
|
||||
From: Paul Mackerras <paulus@ozlabs.org>
|
||||
Date: 2016-07-28 6:11:18
|
||||
|
||||
This moves the transactional memory state save and restore sequences
|
||||
out of the guest entry/exit paths into separate procedures. This is
|
||||
so that these sequences can be used in going into and out of nap
|
||||
in a subsequent patch.
|
||||
|
||||
The only code changes here are (a) saving and restore LR on the
|
||||
stack, since these new procedures get called with a bl instruction,
|
||||
(b) explicitly saving r1 into the PACA instead of assuming that
|
||||
HSTATE_HOST_R1(r13) is already set, and (c) removing an unnecessary
|
||||
and redundant setting of MSR[TM] that should have been removed by
|
||||
commit 9d4d0bdd9e0a ("KVM: PPC: Book3S HV: Add transactional memory
|
||||
support", 2013-09-24) but wasn't.
|
||||
|
||||
Cc: stable@vger.kernel.org # v3.15+
|
||||
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
||||
---
|
||||
arch/powerpc/kvm/book3s_hv_rmhandlers.S | 449 +++++++++++++++++---------------
|
||||
1 file changed, 237 insertions(+), 212 deletions(-)
|
||||
|
||||
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
|
||||
index 0d246fc..cfa4031 100644
|
||||
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
|
||||
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
|
||||
@@ -689,112 +689,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
|
||||
|
||||
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
||||
BEGIN_FTR_SECTION
|
||||
- b skip_tm
|
||||
-END_FTR_SECTION_IFCLR(CPU_FTR_TM)
|
||||
-
|
||||
- /* Turn on TM/FP/VSX/VMX so we can restore them. */
|
||||
- mfmsr r5
|
||||
- li r6, MSR_TM >> 32
|
||||
- sldi r6, r6, 32
|
||||
- or r5, r5, r6
|
||||
- ori r5, r5, MSR_FP
|
||||
- oris r5, r5, (MSR_VEC | MSR_VSX)@h
|
||||
- mtmsrd r5
|
||||
-
|
||||
- /*
|
||||
- * The user may change these outside of a transaction, so they must
|
||||
- * always be context switched.
|
||||
- */
|
||||
- ld r5, VCPU_TFHAR(r4)
|
||||
- ld r6, VCPU_TFIAR(r4)
|
||||
- ld r7, VCPU_TEXASR(r4)
|
||||
- mtspr SPRN_TFHAR, r5
|
||||
- mtspr SPRN_TFIAR, r6
|
||||
- mtspr SPRN_TEXASR, r7
|
||||
-
|
||||
- ld r5, VCPU_MSR(r4)
|
||||
- rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
|
||||
- beq skip_tm /* TM not active in guest */
|
||||
-
|
||||
- /* Make sure the failure summary is set, otherwise we'll program check
|
||||
- * when we trechkpt. It's possible that this might have been not set
|
||||
- * on a kvmppc_set_one_reg() call but we shouldn't let this crash the
|
||||
- * host.
|
||||
- */
|
||||
- oris r7, r7, (TEXASR_FS)@h
|
||||
- mtspr SPRN_TEXASR, r7
|
||||
-
|
||||
- /*
|
||||
- * We need to load up the checkpointed state for the guest.
|
||||
- * We need to do this early as it will blow away any GPRs, VSRs and
|
||||
- * some SPRs.
|
||||
- */
|
||||
-
|
||||
- mr r31, r4
|
||||
- addi r3, r31, VCPU_FPRS_TM
|
||||
- bl load_fp_state
|
||||
- addi r3, r31, VCPU_VRS_TM
|
||||
- bl load_vr_state
|
||||
- mr r4, r31
|
||||
- lwz r7, VCPU_VRSAVE_TM(r4)
|
||||
- mtspr SPRN_VRSAVE, r7
|
||||
-
|
||||
- ld r5, VCPU_LR_TM(r4)
|
||||
- lwz r6, VCPU_CR_TM(r4)
|
||||
- ld r7, VCPU_CTR_TM(r4)
|
||||
- ld r8, VCPU_AMR_TM(r4)
|
||||
- ld r9, VCPU_TAR_TM(r4)
|
||||
- mtlr r5
|
||||
- mtcr r6
|
||||
- mtctr r7
|
||||
- mtspr SPRN_AMR, r8
|
||||
- mtspr SPRN_TAR, r9
|
||||
-
|
||||
- /*
|
||||
- * Load up PPR and DSCR values but don't put them in the actual SPRs
|
||||
- * till the last moment to avoid running with userspace PPR and DSCR for
|
||||
- * too long.
|
||||
- */
|
||||
- ld r29, VCPU_DSCR_TM(r4)
|
||||
- ld r30, VCPU_PPR_TM(r4)
|
||||
-
|
||||
- std r2, PACATMSCRATCH(r13) /* Save TOC */
|
||||
-
|
||||
- /* Clear the MSR RI since r1, r13 are all going to be foobar. */
|
||||
- li r5, 0
|
||||
- mtmsrd r5, 1
|
||||
-
|
||||
- /* Load GPRs r0-r28 */
|
||||
- reg = 0
|
||||
- .rept 29
|
||||
- ld reg, VCPU_GPRS_TM(reg)(r31)
|
||||
- reg = reg + 1
|
||||
- .endr
|
||||
-
|
||||
- mtspr SPRN_DSCR, r29
|
||||
- mtspr SPRN_PPR, r30
|
||||
-
|
||||
- /* Load final GPRs */
|
||||
- ld 29, VCPU_GPRS_TM(29)(r31)
|
||||
- ld 30, VCPU_GPRS_TM(30)(r31)
|
||||
- ld 31, VCPU_GPRS_TM(31)(r31)
|
||||
-
|
||||
- /* TM checkpointed state is now setup. All GPRs are now volatile. */
|
||||
- TRECHKPT
|
||||
-
|
||||
- /* Now let's get back the state we need. */
|
||||
- HMT_MEDIUM
|
||||
- GET_PACA(r13)
|
||||
- ld r29, HSTATE_DSCR(r13)
|
||||
- mtspr SPRN_DSCR, r29
|
||||
- ld r4, HSTATE_KVM_VCPU(r13)
|
||||
- ld r1, HSTATE_HOST_R1(r13)
|
||||
- ld r2, PACATMSCRATCH(r13)
|
||||
-
|
||||
- /* Set the MSR RI since we have our registers back. */
|
||||
- li r5, MSR_RI
|
||||
- mtmsrd r5, 1
|
||||
-skip_tm:
|
||||
+ bl kvmppc_restore_tm
|
||||
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
|
||||
#endif
|
||||
|
||||
/* Load guest PMU registers */
|
||||
@@ -875,12 +771,6 @@ BEGIN_FTR_SECTION
|
||||
/* Skip next section on POWER7 */
|
||||
b 8f
|
||||
END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
|
||||
- /* Turn on TM so we can access TFHAR/TFIAR/TEXASR */
|
||||
- mfmsr r8
|
||||
- li r0, 1
|
||||
- rldimi r8, r0, MSR_TM_LG, 63-MSR_TM_LG
|
||||
- mtmsrd r8
|
||||
-
|
||||
/* Load up POWER8-specific registers */
|
||||
ld r5, VCPU_IAMR(r4)
|
||||
lwz r6, VCPU_PSPB(r4)
|
||||
@@ -1470,106 +1360,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
|
||||
|
||||
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
||||
BEGIN_FTR_SECTION
|
||||
- b 2f
|
||||
-END_FTR_SECTION_IFCLR(CPU_FTR_TM)
|
||||
- /* Turn on TM. */
|
||||
- mfmsr r8
|
||||
- li r0, 1
|
||||
- rldimi r8, r0, MSR_TM_LG, 63-MSR_TM_LG
|
||||
- mtmsrd r8
|
||||
-
|
||||
- ld r5, VCPU_MSR(r9)
|
||||
- rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
|
||||
- beq 1f /* TM not active in guest. */
|
||||
-
|
||||
- li r3, TM_CAUSE_KVM_RESCHED
|
||||
-
|
||||
- /* Clear the MSR RI since r1, r13 are all going to be foobar. */
|
||||
- li r5, 0
|
||||
- mtmsrd r5, 1
|
||||
-
|
||||
- /* All GPRs are volatile at this point. */
|
||||
- TRECLAIM(R3)
|
||||
-
|
||||
- /* Temporarily store r13 and r9 so we have some regs to play with */
|
||||
- SET_SCRATCH0(r13)
|
||||
- GET_PACA(r13)
|
||||
- std r9, PACATMSCRATCH(r13)
|
||||
- ld r9, HSTATE_KVM_VCPU(r13)
|
||||
-
|
||||
- /* Get a few more GPRs free. */
|
||||
- std r29, VCPU_GPRS_TM(29)(r9)
|
||||
- std r30, VCPU_GPRS_TM(30)(r9)
|
||||
- std r31, VCPU_GPRS_TM(31)(r9)
|
||||
-
|
||||
- /* Save away PPR and DSCR soon so don't run with user values. */
|
||||
- mfspr r31, SPRN_PPR
|
||||
- HMT_MEDIUM
|
||||
- mfspr r30, SPRN_DSCR
|
||||
- ld r29, HSTATE_DSCR(r13)
|
||||
- mtspr SPRN_DSCR, r29
|
||||
-
|
||||
- /* Save all but r9, r13 & r29-r31 */
|
||||
- reg = 0
|
||||
- .rept 29
|
||||
- .if (reg != 9) && (reg != 13)
|
||||
- std reg, VCPU_GPRS_TM(reg)(r9)
|
||||
- .endif
|
||||
- reg = reg + 1
|
||||
- .endr
|
||||
- /* ... now save r13 */
|
||||
- GET_SCRATCH0(r4)
|
||||
- std r4, VCPU_GPRS_TM(13)(r9)
|
||||
- /* ... and save r9 */
|
||||
- ld r4, PACATMSCRATCH(r13)
|
||||
- std r4, VCPU_GPRS_TM(9)(r9)
|
||||
-
|
||||
- /* Reload stack pointer and TOC. */
|
||||
- ld r1, HSTATE_HOST_R1(r13)
|
||||
- ld r2, PACATOC(r13)
|
||||
-
|
||||
- /* Set MSR RI now we have r1 and r13 back. */
|
||||
- li r5, MSR_RI
|
||||
- mtmsrd r5, 1
|
||||
-
|
||||
- /* Save away checkpinted SPRs. */
|
||||
- std r31, VCPU_PPR_TM(r9)
|
||||
- std r30, VCPU_DSCR_TM(r9)
|
||||
- mflr r5
|
||||
- mfcr r6
|
||||
- mfctr r7
|
||||
- mfspr r8, SPRN_AMR
|
||||
- mfspr r10, SPRN_TAR
|
||||
- std r5, VCPU_LR_TM(r9)
|
||||
- stw r6, VCPU_CR_TM(r9)
|
||||
- std r7, VCPU_CTR_TM(r9)
|
||||
- std r8, VCPU_AMR_TM(r9)
|
||||
- std r10, VCPU_TAR_TM(r9)
|
||||
-
|
||||
- /* Restore r12 as trap number. */
|
||||
- lwz r12, VCPU_TRAP(r9)
|
||||
-
|
||||
- /* Save FP/VSX. */
|
||||
- addi r3, r9, VCPU_FPRS_TM
|
||||
- bl store_fp_state
|
||||
- addi r3, r9, VCPU_VRS_TM
|
||||
- bl store_vr_state
|
||||
- mfspr r6, SPRN_VRSAVE
|
||||
- stw r6, VCPU_VRSAVE_TM(r9)
|
||||
-1:
|
||||
- /*
|
||||
- * We need to save these SPRs after the treclaim so that the software
|
||||
- * error code is recorded correctly in the TEXASR. Also the user may
|
||||
- * change these outside of a transaction, so they must always be
|
||||
- * context switched.
|
||||
- */
|
||||
- mfspr r5, SPRN_TFHAR
|
||||
- mfspr r6, SPRN_TFIAR
|
||||
- mfspr r7, SPRN_TEXASR
|
||||
- std r5, VCPU_TFHAR(r9)
|
||||
- std r6, VCPU_TFIAR(r9)
|
||||
- std r7, VCPU_TEXASR(r9)
|
||||
-2:
|
||||
+ bl kvmppc_save_tm
|
||||
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
|
||||
#endif
|
||||
|
||||
/* Increment yield count if they have a VPA */
|
||||
@@ -2694,6 +2486,239 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
|
||||
mr r4,r31
|
||||
blr
|
||||
|
||||
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
||||
+/*
|
||||
+ * Save transactional state and TM-related registers.
|
||||
+ * Called with r9 pointing to the vcpu struct.
|
||||
+ * This can modify all checkpointed registers, but
|
||||
+ * restores r1, r2 and r9 (vcpu pointer) before exit.
|
||||
+ */
|
||||
+kvmppc_save_tm:
|
||||
+ mflr r0
|
||||
+ std r0, PPC_LR_STKOFF(r1)
|
||||
+
|
||||
+ /* Turn on TM. */
|
||||
+ mfmsr r8
|
||||
+ li r0, 1
|
||||
+ rldimi r8, r0, MSR_TM_LG, 63-MSR_TM_LG
|
||||
+ mtmsrd r8
|
||||
+
|
||||
+ ld r5, VCPU_MSR(r9)
|
||||
+ rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
|
||||
+ beq 1f /* TM not active in guest. */
|
||||
+
|
||||
+ std r1, HSTATE_HOST_R1(r13)
|
||||
+ li r3, TM_CAUSE_KVM_RESCHED
|
||||
+
|
||||
+ /* Clear the MSR RI since r1, r13 are all going to be foobar. */
|
||||
+ li r5, 0
|
||||
+ mtmsrd r5, 1
|
||||
+
|
||||
+ /* All GPRs are volatile at this point. */
|
||||
+ TRECLAIM(R3)
|
||||
+
|
||||
+ /* Temporarily store r13 and r9 so we have some regs to play with */
|
||||
+ SET_SCRATCH0(r13)
|
||||
+ GET_PACA(r13)
|
||||
+ std r9, PACATMSCRATCH(r13)
|
||||
+ ld r9, HSTATE_KVM_VCPU(r13)
|
||||
+
|
||||
+ /* Get a few more GPRs free. */
|
||||
+ std r29, VCPU_GPRS_TM(29)(r9)
|
||||
+ std r30, VCPU_GPRS_TM(30)(r9)
|
||||
+ std r31, VCPU_GPRS_TM(31)(r9)
|
||||
+
|
||||
+ /* Save away PPR and DSCR soon so don't run with user values. */
|
||||
+ mfspr r31, SPRN_PPR
|
||||
+ HMT_MEDIUM
|
||||
+ mfspr r30, SPRN_DSCR
|
||||
+ ld r29, HSTATE_DSCR(r13)
|
||||
+ mtspr SPRN_DSCR, r29
|
||||
+
|
||||
+ /* Save all but r9, r13 & r29-r31 */
|
||||
+ reg = 0
|
||||
+ .rept 29
|
||||
+ .if (reg != 9) && (reg != 13)
|
||||
+ std reg, VCPU_GPRS_TM(reg)(r9)
|
||||
+ .endif
|
||||
+ reg = reg + 1
|
||||
+ .endr
|
||||
+ /* ... now save r13 */
|
||||
+ GET_SCRATCH0(r4)
|
||||
+ std r4, VCPU_GPRS_TM(13)(r9)
|
||||
+ /* ... and save r9 */
|
||||
+ ld r4, PACATMSCRATCH(r13)
|
||||
+ std r4, VCPU_GPRS_TM(9)(r9)
|
||||
+
|
||||
+ /* Reload stack pointer and TOC. */
|
||||
+ ld r1, HSTATE_HOST_R1(r13)
|
||||
+ ld r2, PACATOC(r13)
|
||||
+
|
||||
+ /* Set MSR RI now we have r1 and r13 back. */
|
||||
+ li r5, MSR_RI
|
||||
+ mtmsrd r5, 1
|
||||
+
|
||||
+ /* Save away checkpinted SPRs. */
|
||||
+ std r31, VCPU_PPR_TM(r9)
|
||||
+ std r30, VCPU_DSCR_TM(r9)
|
||||
+ mflr r5
|
||||
+ mfcr r6
|
||||
+ mfctr r7
|
||||
+ mfspr r8, SPRN_AMR
|
||||
+ mfspr r10, SPRN_TAR
|
||||
+ std r5, VCPU_LR_TM(r9)
|
||||
+ stw r6, VCPU_CR_TM(r9)
|
||||
+ std r7, VCPU_CTR_TM(r9)
|
||||
+ std r8, VCPU_AMR_TM(r9)
|
||||
+ std r10, VCPU_TAR_TM(r9)
|
||||
+
|
||||
+ /* Restore r12 as trap number. */
|
||||
+ lwz r12, VCPU_TRAP(r9)
|
||||
+
|
||||
+ /* Save FP/VSX. */
|
||||
+ addi r3, r9, VCPU_FPRS_TM
|
||||
+ bl store_fp_state
|
||||
+ addi r3, r9, VCPU_VRS_TM
|
||||
+ bl store_vr_state
|
||||
+ mfspr r6, SPRN_VRSAVE
|
||||
+ stw r6, VCPU_VRSAVE_TM(r9)
|
||||
+1:
|
||||
+ /*
|
||||
+ * We need to save these SPRs after the treclaim so that the software
|
||||
+ * error code is recorded correctly in the TEXASR. Also the user may
|
||||
+ * change these outside of a transaction, so they must always be
|
||||
+ * context switched.
|
||||
+ */
|
||||
+ mfspr r5, SPRN_TFHAR
|
||||
+ mfspr r6, SPRN_TFIAR
|
||||
+ mfspr r7, SPRN_TEXASR
|
||||
+ std r5, VCPU_TFHAR(r9)
|
||||
+ std r6, VCPU_TFIAR(r9)
|
||||
+ std r7, VCPU_TEXASR(r9)
|
||||
+
|
||||
+ ld r0, PPC_LR_STKOFF(r1)
|
||||
+ mtlr r0
|
||||
+ blr
|
||||
+
|
||||
+/*
|
||||
+ * Restore transactional state and TM-related registers.
|
||||
+ * Called with r4 pointing to the vcpu struct.
|
||||
+ * This potentially modifies all checkpointed registers.
|
||||
+ * It restores r1, r2, r4 from the PACA.
|
||||
+ */
|
||||
+kvmppc_restore_tm:
|
||||
+ mflr r0
|
||||
+ std r0, PPC_LR_STKOFF(r1)
|
||||
+
|
||||
+ /* Turn on TM/FP/VSX/VMX so we can restore them. */
|
||||
+ mfmsr r5
|
||||
+ li r6, MSR_TM >> 32
|
||||
+ sldi r6, r6, 32
|
||||
+ or r5, r5, r6
|
||||
+ ori r5, r5, MSR_FP
|
||||
+ oris r5, r5, (MSR_VEC | MSR_VSX)@h
|
||||
+ mtmsrd r5
|
||||
+
|
||||
+ /*
|
||||
+ * The user may change these outside of a transaction, so they must
|
||||
+ * always be context switched.
|
||||
+ */
|
||||
+ ld r5, VCPU_TFHAR(r4)
|
||||
+ ld r6, VCPU_TFIAR(r4)
|
||||
+ ld r7, VCPU_TEXASR(r4)
|
||||
+ mtspr SPRN_TFHAR, r5
|
||||
+ mtspr SPRN_TFIAR, r6
|
||||
+ mtspr SPRN_TEXASR, r7
|
||||
+
|
||||
+ ld r5, VCPU_MSR(r4)
|
||||
+ rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
|
||||
+ beqlr /* TM not active in guest */
|
||||
+ std r1, HSTATE_HOST_R1(r13)
|
||||
+
|
||||
+ /* Make sure the failure summary is set, otherwise we'll program check
|
||||
+ * when we trechkpt. It's possible that this might have been not set
|
||||
+ * on a kvmppc_set_one_reg() call but we shouldn't let this crash the
|
||||
+ * host.
|
||||
+ */
|
||||
+ oris r7, r7, (TEXASR_FS)@h
|
||||
+ mtspr SPRN_TEXASR, r7
|
||||
+
|
||||
+ /*
|
||||
+ * We need to load up the checkpointed state for the guest.
|
||||
+ * We need to do this early as it will blow away any GPRs, VSRs and
|
||||
+ * some SPRs.
|
||||
+ */
|
||||
+
|
||||
+ mr r31, r4
|
||||
+ addi r3, r31, VCPU_FPRS_TM
|
||||
+ bl load_fp_state
|
||||
+ addi r3, r31, VCPU_VRS_TM
|
||||
+ bl load_vr_state
|
||||
+ mr r4, r31
|
||||
+ lwz r7, VCPU_VRSAVE_TM(r4)
|
||||
+ mtspr SPRN_VRSAVE, r7
|
||||
+
|
||||
+ ld r5, VCPU_LR_TM(r4)
|
||||
+ lwz r6, VCPU_CR_TM(r4)
|
||||
+ ld r7, VCPU_CTR_TM(r4)
|
||||
+ ld r8, VCPU_AMR_TM(r4)
|
||||
+ ld r9, VCPU_TAR_TM(r4)
|
||||
+ mtlr r5
|
||||
+ mtcr r6
|
||||
+ mtctr r7
|
||||
+ mtspr SPRN_AMR, r8
|
||||
+ mtspr SPRN_TAR, r9
|
||||
+
|
||||
+ /*
|
||||
+ * Load up PPR and DSCR values but don't put them in the actual SPRs
|
||||
+ * till the last moment to avoid running with userspace PPR and DSCR for
|
||||
+ * too long.
|
||||
+ */
|
||||
+ ld r29, VCPU_DSCR_TM(r4)
|
||||
+ ld r30, VCPU_PPR_TM(r4)
|
||||
+
|
||||
+ std r2, PACATMSCRATCH(r13) /* Save TOC */
|
||||
+
|
||||
+ /* Clear the MSR RI since r1, r13 are all going to be foobar. */
|
||||
+ li r5, 0
|
||||
+ mtmsrd r5, 1
|
||||
+
|
||||
+ /* Load GPRs r0-r28 */
|
||||
+ reg = 0
|
||||
+ .rept 29
|
||||
+ ld reg, VCPU_GPRS_TM(reg)(r31)
|
||||
+ reg = reg + 1
|
||||
+ .endr
|
||||
+
|
||||
+ mtspr SPRN_DSCR, r29
|
||||
+ mtspr SPRN_PPR, r30
|
||||
+
|
||||
+ /* Load final GPRs */
|
||||
+ ld 29, VCPU_GPRS_TM(29)(r31)
|
||||
+ ld 30, VCPU_GPRS_TM(30)(r31)
|
||||
+ ld 31, VCPU_GPRS_TM(31)(r31)
|
||||
+
|
||||
+ /* TM checkpointed state is now setup. All GPRs are now volatile. */
|
||||
+ TRECHKPT
|
||||
+
|
||||
+ /* Now let's get back the state we need. */
|
||||
+ HMT_MEDIUM
|
||||
+ GET_PACA(r13)
|
||||
+ ld r29, HSTATE_DSCR(r13)
|
||||
+ mtspr SPRN_DSCR, r29
|
||||
+ ld r4, HSTATE_KVM_VCPU(r13)
|
||||
+ ld r1, HSTATE_HOST_R1(r13)
|
||||
+ ld r2, PACATMSCRATCH(r13)
|
||||
+
|
||||
+ /* Set the MSR RI since we have our registers back. */
|
||||
+ li r5, MSR_RI
|
||||
+ mtmsrd r5, 1
|
||||
+
|
||||
+ ld r0, PPC_LR_STKOFF(r1)
|
||||
+ mtlr r0
|
||||
+ blr
|
||||
+#endif
|
||||
+
|
||||
/*
|
||||
* We come here if we get any exception or interrupt while we are
|
||||
* executing host real mode code while in guest MMU context.
|
||||
--
|
||||
2.8.0.rc3
|
||||
67
kvm-ppc-Book3S-HV-Save-restore-TM-state.patch
Normal file
67
kvm-ppc-Book3S-HV-Save-restore-TM-state.patch
Normal file
@ -0,0 +1,67 @@
|
||||
Subject: [PATCH 2/2] KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
|
||||
From: Paul Mackerras <paulus@ozlabs.org>
|
||||
Date: 2016-07-28 6:11:19
|
||||
|
||||
It turns out that if the guest does a H_CEDE while the CPU is in
|
||||
a transactional state, and the H_CEDE does a nap, and the nap
|
||||
loses the architected state of the CPU (which is is allowed to do),
|
||||
then we lose the checkpointed state of the virtual CPU. In addition,
|
||||
the transactional-memory state recorded in the MSR gets reset back
|
||||
to non-transactional, and when we try to return to the guest, we take
|
||||
a TM bad thing type of program interrupt because we are trying to
|
||||
transition from non-transactional to transactional with a hrfid
|
||||
instruction, which is not permitted.
|
||||
|
||||
The result of the program interrupt occurring at that point is that
|
||||
the host CPU will hang in an infinite loop with interrupts disabled.
|
||||
Thus this is a denial of service vulnerability in the host which can
|
||||
be triggered by any guest (and depending on the guest kernel, it can
|
||||
potentially triggered by unprivileged userspace in the guest).
|
||||
|
||||
This vulnerability has been assigned the ID CVE-2016-5412.
|
||||
|
||||
To fix this, we save the TM state before napping and restore it
|
||||
on exit from the nap, when handling a H_CEDE in real mode. The
|
||||
case where H_CEDE exits to host virtual mode is already OK (as are
|
||||
other hcalls which exit to host virtual mode) because the exit
|
||||
path saves the TM state.
|
||||
|
||||
Cc: stable@vger.kernel.org # v3.15+
|
||||
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
||||
---
|
||||
arch/powerpc/kvm/book3s_hv_rmhandlers.S | 13 +++++++++++++
|
||||
1 file changed, 13 insertions(+)
|
||||
|
||||
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
|
||||
index cfa4031..543124f 100644
|
||||
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
|
||||
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
|
||||
@@ -2093,6 +2093,13 @@ _GLOBAL(kvmppc_h_cede) /* r3 = vcpu pointer, r11 = msr, r13 = paca */
|
||||
/* save FP state */
|
||||
bl kvmppc_save_fp
|
||||
|
||||
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
||||
+BEGIN_FTR_SECTION
|
||||
+ ld r9, HSTATE_KVM_VCPU(r13)
|
||||
+ bl kvmppc_save_tm
|
||||
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
|
||||
+#endif
|
||||
+
|
||||
/*
|
||||
* Set DEC to the smaller of DEC and HDEC, so that we wake
|
||||
* no later than the end of our timeslice (HDEC interrupts
|
||||
@@ -2169,6 +2176,12 @@ kvm_end_cede:
|
||||
bl kvmhv_accumulate_time
|
||||
#endif
|
||||
|
||||
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
||||
+BEGIN_FTR_SECTION
|
||||
+ bl kvmppc_restore_tm
|
||||
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
|
||||
+#endif
|
||||
+
|
||||
/* load up FP state */
|
||||
bl kvmppc_load_fp
|
||||
|
||||
--
|
||||
2.8.0.rc3
|
||||
Loading…
Reference in New Issue
Block a user