Commit 19778785 authored by Martin Kepplinger's avatar Martin Kepplinger
Browse files

Merge tag 'v5.7.4' into stable/5.7.4

This is the 5.7.4 stable release
parents ac2207a3 901e2c6c
Pipeline #56330 passed with stage
in 51 minutes and 32 seconds
......@@ -492,6 +492,7 @@ What: /sys/devices/system/cpu/vulnerabilities
/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
/sys/devices/system/cpu/vulnerabilities/l1tf
/sys/devices/system/cpu/vulnerabilities/mds
/sys/devices/system/cpu/vulnerabilities/srbds
/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
/sys/devices/system/cpu/vulnerabilities/itlb_multihit
Date: January 2018
......
......@@ -14,3 +14,4 @@ are configurable at compile, boot or run time.
mds
tsx_async_abort
multihit.rst
special-register-buffer-data-sampling.rst
.. SPDX-License-Identifier: GPL-2.0
SRBDS - Special Register Buffer Data Sampling
=============================================
SRBDS is a hardware vulnerability that allows MDS :doc:`mds` techniques to
infer values returned from special register accesses. Special register
accesses are accesses to off core registers. According to Intel's evaluation,
the special register reads that have a security expectation of privacy are
RDRAND, RDSEED and SGX EGETKEY.
When RDRAND, RDSEED and EGETKEY instructions are used, the data is moved
to the core through the special register mechanism that is susceptible
to MDS attacks.
Affected processors
--------------------
Core models (desktop, mobile, Xeon-E3) that implement RDRAND and/or RDSEED may
be affected.
A processor is affected by SRBDS if its Family_Model and stepping is
in the following list, with the exception of the listed processors
exporting MDS_NO while Intel TSX is available yet not enabled. The
latter class of processors are only affected when Intel TSX is enabled
by software using TSX_CTRL_MSR otherwise they are not affected.
============= ============ ========
common name Family_Model Stepping
============= ============ ========
IvyBridge 06_3AH All
Haswell 06_3CH All
Haswell_L 06_45H All
Haswell_G 06_46H All
Broadwell_G 06_47H All
Broadwell 06_3DH All
Skylake_L 06_4EH All
Skylake 06_5EH All
Kabylake_L 06_8EH <= 0xC
Kabylake 06_9EH <= 0xD
============= ============ ========
Related CVEs
------------
The following CVE entry is related to this SRBDS issue:
============== ===== =====================================
CVE-2020-0543 SRBDS Special Register Buffer Data Sampling
============== ===== =====================================
Attack scenarios
----------------
An unprivileged user can extract values returned from RDRAND and RDSEED
executed on another core or sibling thread using MDS techniques.
Mitigation mechanism
-------------------
Intel will release microcode updates that modify the RDRAND, RDSEED, and
EGETKEY instructions to overwrite secret special register data in the shared
staging buffer before the secret data can be accessed by another logical
processor.
During execution of the RDRAND, RDSEED, or EGETKEY instructions, off-core
accesses from other logical processors will be delayed until the special
register read is complete and the secret data in the shared staging buffer is
overwritten.
This has three effects on performance:
#. RDRAND, RDSEED, or EGETKEY instructions have higher latency.
#. Executing RDRAND at the same time on multiple logical processors will be
serialized, resulting in an overall reduction in the maximum RDRAND
bandwidth.
#. Executing RDRAND, RDSEED or EGETKEY will delay memory accesses from other
logical processors that miss their core caches, with an impact similar to
legacy locked cache-line-split accesses.
The microcode updates provide an opt-out mechanism (RNGDS_MITG_DIS) to disable
the mitigation for RDRAND and RDSEED instructions executed outside of Intel
Software Guard Extensions (Intel SGX) enclaves. On logical processors that
disable the mitigation using this opt-out mechanism, RDRAND and RDSEED do not
take longer to execute and do not impact performance of sibling logical
processors memory accesses. The opt-out mechanism does not affect Intel SGX
enclaves (including execution of RDRAND or RDSEED inside an enclave, as well
as EGETKEY execution).
IA32_MCU_OPT_CTRL MSR Definition
--------------------------------
Along with the mitigation for this issue, Intel added a new thread-scope
IA32_MCU_OPT_CTRL MSR, (address 0x123). The presence of this MSR and
RNGDS_MITG_DIS (bit 0) is enumerated by CPUID.(EAX=07H,ECX=0).EDX[SRBDS_CTRL =
9]==1. This MSR is introduced through the microcode update.
Setting IA32_MCU_OPT_CTRL[0] (RNGDS_MITG_DIS) to 1 for a logical processor
disables the mitigation for RDRAND and RDSEED executed outside of an Intel SGX
enclave on that logical processor. Opting out of the mitigation for a
particular logical processor does not affect the RDRAND and RDSEED mitigations
for other logical processors.
Note that inside of an Intel SGX enclave, the mitigation is applied regardless
of the value of RNGDS_MITG_DS.
Mitigation control on the kernel command line
---------------------------------------------
The kernel command line allows control over the SRBDS mitigation at boot time
with the option "srbds=". The option for this is:
============= =============================================================
off This option disables SRBDS mitigation for RDRAND and RDSEED on
affected platforms.
============= =============================================================
SRBDS System Information
-----------------------
The Linux kernel provides vulnerability status information through sysfs. For
SRBDS this can be accessed by the following sysfs file:
/sys/devices/system/cpu/vulnerabilities/srbds
The possible values contained in this file are:
============================== =============================================
Not affected Processor not vulnerable
Vulnerable Processor vulnerable and mitigation disabled
Vulnerable: No microcode Processor vulnerable and microcode is missing
mitigation
Mitigation: Microcode Processor is vulnerable and mitigation is in
effect.
Mitigation: TSX disabled Processor is only vulnerable when TSX is
enabled while this system was booted with TSX
disabled.
Unknown: Dependent on
hypervisor status Running on virtual guest processor that is
affected but with no way to know if host
processor is mitigated or vulnerable.
============================== =============================================
SRBDS Default mitigation
------------------------
This new microcode serializes processor access during execution of RDRAND,
RDSEED ensures that the shared buffer is overwritten before it is released for
reuse. Use the "srbds=off" kernel command line to disable the mitigation for
RDRAND and RDSEED.
......@@ -4757,6 +4757,26 @@
the kernel will oops in either "warn" or "fatal"
mode.
srbds= [X86,INTEL]
Control the Special Register Buffer Data Sampling
(SRBDS) mitigation.
Certain CPUs are vulnerable to an MDS-like
exploit which can leak bits from the random
number generator.
By default, this issue is mitigated by
microcode. However, the microcode fix can cause
the RDRAND and RDSEED instructions to become
much slower. Among other effects, this will
result in reduced throughput from /dev/urandom.
The microcode mitigation can be disabled with
the following option:
off: Disable mitigation and remove
performance impact to RDRAND and RDSEED
srcutree.counter_wrap_check [KNL]
Specifies how frequently to check for
grace-period sequence counter wrap for the
......
......@@ -159,11 +159,15 @@ Byte sequences
distance = 16384 + (H << 14) + D
state = S (copy S literals after this block)
End of stream is reached if distance == 16384
In version 1 only, to prevent ambiguity with the RLE case when
((distance & 0x803f) == 0x803f) && (261 <= length <= 264), the
compressor must not emit block copies where distance and length
meet these conditions.
In version 1 only, this instruction is also used to encode a run of
zeros if distance = 0xbfff, i.e. H = 1 and the D bits are all 1.
zeros if distance = 0xbfff, i.e. H = 1 and the D bits are all 1.
In this case, it is followed by a fourth byte, X.
run length = ((X << 3) | (0 0 0 0 0 L L L)) + 4.
run length = ((X << 3) | (0 0 0 0 0 L L L)) + 4
0 0 1 L L L L L (32..63)
Copy of small block within 16kB distance (preferably less than 34B)
......
# SPDX-License-Identifier: GPL-2.0
VERSION = 5
PATCHLEVEL = 7
SUBLEVEL = 0
SUBLEVEL = 4
EXTRAVERSION =
NAME = Kleptomaniac Octopus
......
......@@ -125,8 +125,6 @@
bus-width = <8>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_sdmmc0_default>;
non-removable;
mmc-ddr-1_8v;
status = "okay";
};
......
......@@ -12,6 +12,7 @@
#include <linux/efi.h>
#include <linux/memblock.h>
#include <linux/psci.h>
#include <linux/stddef.h>
#include <asm/cputype.h>
#include <asm/io.h>
......@@ -31,14 +32,14 @@
* is therefore used to delimit the MADT GICC structure minimum length
* appropriately.
*/
#define ACPI_MADT_GICC_MIN_LENGTH ACPI_OFFSET( \
#define ACPI_MADT_GICC_MIN_LENGTH offsetof( \
struct acpi_madt_generic_interrupt, efficiency_class)
#define BAD_MADT_GICC_ENTRY(entry, end) \
(!(entry) || (entry)->header.length < ACPI_MADT_GICC_MIN_LENGTH || \
(unsigned long)(entry) + (entry)->header.length > (end))
#define ACPI_MADT_GICC_SPE (ACPI_OFFSET(struct acpi_madt_generic_interrupt, \
#define ACPI_MADT_GICC_SPE (offsetof(struct acpi_madt_generic_interrupt, \
spe_interrupt) + sizeof(u16))
/* Basic configuration for ACPI */
......
......@@ -112,12 +112,6 @@ static inline void vcpu_ptrauth_disable(struct kvm_vcpu *vcpu)
vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
}
static inline void vcpu_ptrauth_setup_lazy(struct kvm_vcpu *vcpu)
{
if (vcpu_has_ptrauth(vcpu))
vcpu_ptrauth_disable(vcpu);
}
static inline unsigned long vcpu_get_vsesr(struct kvm_vcpu *vcpu)
{
return vcpu->arch.vsesr_el2;
......
......@@ -405,8 +405,10 @@ void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg);
* CP14 and CP15 live in the same array, as they are backed by the
* same system registers.
*/
#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r)])
#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r)])
#define CPx_BIAS IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r) ^ CPx_BIAS])
#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r) ^ CPx_BIAS])
struct kvm_vm_stat {
ulong remote_tlb_flush;
......
......@@ -162,31 +162,16 @@ static int handle_sve(struct kvm_vcpu *vcpu, struct kvm_run *run)
return 1;
}
#define __ptrauth_save_key(regs, key) \
({ \
regs[key ## KEYLO_EL1] = read_sysreg_s(SYS_ ## key ## KEYLO_EL1); \
regs[key ## KEYHI_EL1] = read_sysreg_s(SYS_ ## key ## KEYHI_EL1); \
})
/*
* Handle the guest trying to use a ptrauth instruction, or trying to access a
* ptrauth register.
*/
void kvm_arm_vcpu_ptrauth_trap(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *ctxt;
if (vcpu_has_ptrauth(vcpu)) {
if (vcpu_has_ptrauth(vcpu))
vcpu_ptrauth_enable(vcpu);
ctxt = vcpu->arch.host_cpu_context;
__ptrauth_save_key(ctxt->sys_regs, APIA);
__ptrauth_save_key(ctxt->sys_regs, APIB);
__ptrauth_save_key(ctxt->sys_regs, APDA);
__ptrauth_save_key(ctxt->sys_regs, APDB);
__ptrauth_save_key(ctxt->sys_regs, APGA);
} else {
else
kvm_inject_undefined(vcpu);
}
}
/*
......
......@@ -1305,10 +1305,16 @@ static bool access_clidr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
static bool access_csselr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
int reg = r->reg;
/* See the 32bit mapping in kvm_host.h */
if (p->is_aarch32)
reg = r->reg / 2;
if (p->is_write)
vcpu_write_sys_reg(vcpu, p->regval, r->reg);
vcpu_write_sys_reg(vcpu, p->regval, reg);
else
p->regval = vcpu_read_sys_reg(vcpu, r->reg);
p->regval = vcpu_read_sys_reg(vcpu, reg);
return true;
}
......
......@@ -274,8 +274,12 @@ enum emulation_result {
#define MIPS3_PG_SHIFT 6
#define MIPS3_PG_FRAME 0x3fffffc0
#if defined(CONFIG_64BIT)
#define VPN2_MASK GENMASK(cpu_vmbits - 1, 13)
#else
#define VPN2_MASK 0xffffe000
#define KVM_ENTRYHI_ASID MIPS_ENTRYHI_ASID
#endif
#define KVM_ENTRYHI_ASID cpu_asid_mask(&boot_cpu_data)
#define TLB_IS_GLOBAL(x) ((x).tlb_lo[0] & (x).tlb_lo[1] & ENTRYLO_G)
#define TLB_VPN2(x) ((x).tlb_hi & VPN2_MASK)
#define TLB_ASID(x) ((x).tlb_hi & KVM_ENTRYHI_ASID)
......
......@@ -60,6 +60,7 @@ struct pg_state {
unsigned long start_address;
unsigned long start_pa;
unsigned long last_pa;
unsigned long page_size;
unsigned int level;
u64 current_flags;
bool check_wx;
......@@ -157,9 +158,9 @@ static void dump_addr(struct pg_state *st, unsigned long addr)
#endif
pt_dump_seq_printf(st->seq, REG "-" REG " ", st->start_address, addr - 1);
if (st->start_pa == st->last_pa && st->start_address + PAGE_SIZE != addr) {
if (st->start_pa == st->last_pa && st->start_address + st->page_size != addr) {
pt_dump_seq_printf(st->seq, "[" REG "]", st->start_pa);
delta = PAGE_SIZE >> 10;
delta = st->page_size >> 10;
} else {
pt_dump_seq_printf(st->seq, " " REG " ", st->start_pa);
delta = (addr - st->start_address) >> 10;
......@@ -190,7 +191,7 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr)
}
static void note_page(struct pg_state *st, unsigned long addr,
unsigned int level, u64 val)
unsigned int level, u64 val, unsigned long page_size)
{
u64 flag = val & pg_level[level].mask;
u64 pa = val & PTE_RPN_MASK;
......@@ -202,6 +203,7 @@ static void note_page(struct pg_state *st, unsigned long addr,
st->start_address = addr;
st->start_pa = pa;
st->last_pa = pa;
st->page_size = page_size;
pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
/*
* Dump the section of virtual memory when:
......@@ -213,7 +215,7 @@ static void note_page(struct pg_state *st, unsigned long addr,
*/
} else if (flag != st->current_flags || level != st->level ||
addr >= st->marker[1].start_address ||
(pa != st->last_pa + PAGE_SIZE &&
(pa != st->last_pa + st->page_size &&
(pa != st->start_pa || st->start_pa != st->last_pa))) {
/* Check the PTE flags */
......@@ -241,6 +243,7 @@ static void note_page(struct pg_state *st, unsigned long addr,
st->start_address = addr;
st->start_pa = pa;
st->last_pa = pa;
st->page_size = page_size;
st->current_flags = flag;
st->level = level;
} else {
......@@ -256,7 +259,7 @@ static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start)
for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
addr = start + i * PAGE_SIZE;
note_page(st, addr, 4, pte_val(*pte));
note_page(st, addr, 4, pte_val(*pte), PAGE_SIZE);
}
}
......@@ -273,7 +276,7 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
/* pmd exists */
walk_pte(st, pmd, addr);
else
note_page(st, addr, 3, pmd_val(*pmd));
note_page(st, addr, 3, pmd_val(*pmd), PMD_SIZE);
}
}
......@@ -289,7 +292,7 @@ static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start)
/* pud exists */
walk_pmd(st, pud, addr);
else
note_page(st, addr, 2, pud_val(*pud));
note_page(st, addr, 2, pud_val(*pud), PUD_SIZE);
}
}
......@@ -308,7 +311,7 @@ static void walk_pagetables(struct pg_state *st)
/* pgd exists */
walk_pud(st, pgd, addr);
else
note_page(st, addr, 1, pgd_val(*pgd));
note_page(st, addr, 1, pgd_val(*pgd), PGDIR_SIZE);
}
}
......@@ -363,7 +366,7 @@ static int ptdump_show(struct seq_file *m, void *v)
/* Traverse kernel page tables */
walk_pagetables(&st);
note_page(&st, 0, 0, 0);
note_page(&st, 0, 0, 0, 0);
return 0;
}
......
......@@ -19,6 +19,7 @@
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/msi.h>
#include <linux/vmalloc.h>
#include <asm/debugfs.h>
#include <asm/prom.h>
......@@ -1017,12 +1018,16 @@ EXPORT_SYMBOL_GPL(is_xive_irq);
void xive_cleanup_irq_data(struct xive_irq_data *xd)
{
if (xd->eoi_mmio) {
unmap_kernel_range((unsigned long)xd->eoi_mmio,
1u << xd->esb_shift);
iounmap(xd->eoi_mmio);
if (xd->eoi_mmio == xd->trig_mmio)
xd->trig_mmio = NULL;
xd->eoi_mmio = NULL;
}
if (xd->trig_mmio) {
unmap_kernel_range((unsigned long)xd->trig_mmio,
1u << xd->esb_shift);
iounmap(xd->trig_mmio);
xd->trig_mmio = NULL;
}
......
......@@ -309,14 +309,13 @@ out:
int clp_disable_fh(struct zpci_dev *zdev)
{
u32 fh = zdev->fh;
int rc;
if (!zdev_enabled(zdev))
return 0;
rc = clp_set_pci_fn(zdev, 0, CLP_SET_DISABLE_PCI_FN);
zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
return rc;
}
......
......@@ -1892,8 +1892,8 @@ static __initconst const u64 tnt_hw_cache_extra_regs
static struct extra_reg intel_tnt_extra_regs[] __read_mostly = {
/* must define OFFCORE_RSP_X first, see intel_fixup_er() */
INTEL_UEVENT_EXTRA_REG(0x01b7, MSR_OFFCORE_RSP_0, 0xffffff9fffull, RSP_0),
INTEL_UEVENT_EXTRA_REG(0x02b7, MSR_OFFCORE_RSP_1, 0xffffff9fffull, RSP_1),
INTEL_UEVENT_EXTRA_REG(0x01b7, MSR_OFFCORE_RSP_0, 0x800ff0ffffff9fffull, RSP_0),
INTEL_UEVENT_EXTRA_REG(0x02b7, MSR_OFFCORE_RSP_1, 0xff0ffffff9fffull, RSP_1),
EVENT_EXTRA_END
};
......
......@@ -20,12 +20,14 @@
#define X86_CENTAUR_FAM6_C7_D 0xd
#define X86_CENTAUR_FAM6_NANO 0xf
#define X86_STEPPINGS(mins, maxs) GENMASK(maxs, mins)
/**
* X86_MATCH_VENDOR_FAM_MODEL_FEATURE - Base macro for CPU matching
* X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE - Base macro for CPU matching
* @_vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
* The name is expanded to X86_VENDOR_@_vendor
* @_family: The family number or X86_FAMILY_ANY
* @_model: The model number, model constant or X86_MODEL_ANY
* @_steppings: Bitmask for steppings, stepping constant or X86_STEPPING_ANY
* @_feature: A X86_FEATURE bit or X86_FEATURE_ANY
* @_data: Driver specific data or NULL. The internal storage
* format is unsigned long. The supplied value, pointer
......@@ -37,15 +39,34 @@
* into another macro at the usage site for good reasons, then please
* start this local macro with X86_MATCH to allow easy grepping.
*/
#define X86_MATCH_VENDOR_FAM_MODEL_FEATURE(_vendor, _family, _model, \
_feature, _data) { \
#define X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(_vendor, _family, _model, \
_steppings, _feature, _data) { \
.vendor = X86_VENDOR_##_vendor, \
.family = _family, \
.model = _model, \
.steppings = _steppings, \
.feature = _feature, \
.driver_data = (unsigned long) _data \
}
/**
* X86_MATCH_VENDOR_FAM_MODEL_FEATURE - Macro for CPU matching
* @_vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
* The name is expanded to X86_VENDOR_@_vendor
* @_family: The family number or X86_FAMILY_ANY
* @_model: The model number, model constant or X86_MODEL_ANY
* @_feature: A X86_FEATURE bit or X86_FEATURE_ANY
* @_data: Driver specific data or NULL. The internal storage
* format is unsigned long. The supplied value, pointer
* etc. is casted to unsigned long internally.
*
* The steppings arguments of X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE() is
* set to wildcards.
*/
#define X86_MATCH_VENDOR_FAM_MODEL_FEATURE(vendor, family, model, feature, data) \
X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(vendor, family, model, \
X86_STEPPING_ANY, feature, data)
/**
* X86_MATCH_VENDOR_FAM_FEATURE - Macro for matching vendor, family and CPU feature
* @vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
......
......@@ -362,6 +362,7 @@
#define X86_FEATURE_AVX512_4FMAPS (18*32+ 3) /* AVX-512 Multiply Accumulation Single precision */
#define X86_FEATURE_FSRM (18*32+ 4) /* Fast Short Rep Mov */
#define X86_FEATURE_AVX512_VP2INTERSECT (18*32+ 8) /* AVX-512 Intersect for D/Q */
#define X86_FEATURE_SRBDS_CTRL (18*32+ 9) /* "" SRBDS mitigation MSR available */
#define X86_FEATURE_MD_CLEAR (18*32+10) /* VERW clears CPU buffers */
#define X86_FEATURE_TSX_FORCE_ABORT (18*32+13) /* "" TSX_FORCE_ABORT */
#define X86_FEATURE_PCONFIG (18*32+18) /* Intel PCONFIG */
......@@ -407,5 +408,6 @@
#define X86_BUG_SWAPGS X86_BUG(21) /* CPU is affected by speculation through SWAPGS */
#define X86_BUG_TAA X86_BUG(22) /* CPU is affected by TSX Async Abort(TAA) */
#define X86_BUG_ITLB_MULTIHIT X86_BUG(23) /* CPU may incur MCE during certain page attribute changes */
#define X86_BUG_SRBDS X86_BUG(24) /* CPU may leak RNG bits if not mitigated */
#endif /* _ASM_X86_CPUFEATURES_H */
......@@ -128,6 +128,10 @@
#define TSX_CTRL_RTM_DISABLE BIT(0) /* Disable RTM feature */
#define TSX_CTRL_CPUID_CLEAR BIT(1) /* Disable TSX enumeration */
/* SRBDS support */
#define MSR_IA32_MCU_OPT_CTRL 0x00000123
#define RNGDS_MITG_DIS BIT(0)
#define MSR_IA32_SYSENTER_CS 0x00000174
#define MSR_IA32_SYSENTER_ESP 0x00000175
#define MSR_IA32_SYSENTER_EIP 0x00000176
......
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