[GIT PULL] perf fixes

From: Ingo Molnar
Date: Sat Jun 29 2019 - 04:55:21 EST

Linus,

Please pull the latest perf-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus

# HEAD: 8b12b812f5367c2469fb937da7e28dd321ad8d7b perf/x86/regs: Use PERF_REG_EXTENDED_MASK

Various fixes, most of them related to bugs perf fuzzing found in the x86
code.

Thanks,

Ingo

------------------>
Kan Liang (5):
perf/x86: Disable extended registers for non-supported PMUs
perf/x86/regs: Check reserved bits
perf/x86: Clean up PEBS_XMM_REGS
perf/x86: Remove pmu->pebs_no_xmm_regs
perf/x86/regs: Use PERF_REG_EXTENDED_MASK

Peter Zijlstra (1):
perf/core: Fix perf_sample_regs_user() mm check

Ravi Bangoria (1):
perf/ioctl: Add check for the sample_period value


arch/x86/events/core.c | 6 +++---
arch/x86/events/intel/ds.c | 9 ++++-----
arch/x86/events/perf_event.h | 21 +--------------------
arch/x86/include/uapi/asm/perf_regs.h | 3 +++
arch/x86/kernel/perf_regs.c | 7 +++++--
include/linux/perf_event.h | 1 +
include/linux/perf_regs.h | 8 ++++++++
kernel/events/core.c | 23 ++++++++++++++++++-----
tools/arch/x86/include/uapi/asm/perf_regs.h | 3 +++
tools/perf/arch/x86/include/perf_regs.h | 1 -
tools/perf/arch/x86/util/perf_regs.c | 4 ++--
11 files changed, 48 insertions(+), 38 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index f315425d8468..52a97463cb24 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -561,14 +561,14 @@ int x86_pmu_hw_config(struct perf_event *event)
}

/* sample_regs_user never support XMM registers */
- if (unlikely(event->attr.sample_regs_user & PEBS_XMM_REGS))
+ if (unlikely(event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK))
return -EINVAL;
/*
* Besides the general purpose registers, XMM registers may
* be collected in PEBS on some platforms, e.g. Icelake
*/
- if (unlikely(event->attr.sample_regs_intr & PEBS_XMM_REGS)) {
- if (x86_pmu.pebs_no_xmm_regs)
+ if (unlikely(event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK)) {
+ if (!(event->pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS))
return -EINVAL;

if (!event->attr.precise_ip)
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 7acc526b4ad2..505c73dc6a73 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -987,7 +987,7 @@ static u64 pebs_update_adaptive_cfg(struct perf_event *event)
pebs_data_cfg |= PEBS_DATACFG_GP;

if ((sample_type & PERF_SAMPLE_REGS_INTR) &&
- (attr->sample_regs_intr & PEBS_XMM_REGS))
+ (attr->sample_regs_intr & PERF_REG_EXTENDED_MASK))
pebs_data_cfg |= PEBS_DATACFG_XMMS;

if (sample_type & PERF_SAMPLE_BRANCH_STACK) {
@@ -1964,10 +1964,9 @@ void __init intel_ds_init(void)
x86_pmu.bts = boot_cpu_has(X86_FEATURE_BTS);
x86_pmu.pebs = boot_cpu_has(X86_FEATURE_PEBS);
x86_pmu.pebs_buffer_size = PEBS_BUFFER_SIZE;
- if (x86_pmu.version <= 4) {
+ if (x86_pmu.version <= 4)
x86_pmu.pebs_no_isolation = 1;
- x86_pmu.pebs_no_xmm_regs = 1;
- }
+
if (x86_pmu.pebs) {
char pebs_type = x86_pmu.intel_cap.pebs_trap ? '+' : '-';
char *pebs_qual = "";
@@ -2020,9 +2019,9 @@ void __init intel_ds_init(void)
PERF_SAMPLE_TIME;
x86_pmu.flags |= PMU_FL_PEBS_ALL;
pebs_qual = "-baseline";
+ x86_get_pmu()->capabilities |= PERF_PMU_CAP_EXTENDED_REGS;
} else {
/* Only basic record supported */
- x86_pmu.pebs_no_xmm_regs = 1;
x86_pmu.large_pebs_flags &=
~(PERF_SAMPLE_ADDR |
PERF_SAMPLE_TIME |
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index a6ac2f4f76fc..4e346856ee19 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -121,24 +121,6 @@ struct amd_nb {
(1ULL << PERF_REG_X86_R14) | \
(1ULL << PERF_REG_X86_R15))

-#define PEBS_XMM_REGS \
- ((1ULL << PERF_REG_X86_XMM0) | \
- (1ULL << PERF_REG_X86_XMM1) | \
- (1ULL << PERF_REG_X86_XMM2) | \
- (1ULL << PERF_REG_X86_XMM3) | \
- (1ULL << PERF_REG_X86_XMM4) | \
- (1ULL << PERF_REG_X86_XMM5) | \
- (1ULL << PERF_REG_X86_XMM6) | \
- (1ULL << PERF_REG_X86_XMM7) | \
- (1ULL << PERF_REG_X86_XMM8) | \
- (1ULL << PERF_REG_X86_XMM9) | \
- (1ULL << PERF_REG_X86_XMM10) | \
- (1ULL << PERF_REG_X86_XMM11) | \
- (1ULL << PERF_REG_X86_XMM12) | \
- (1ULL << PERF_REG_X86_XMM13) | \
- (1ULL << PERF_REG_X86_XMM14) | \
- (1ULL << PERF_REG_X86_XMM15))
-
/*
* Per register state.
*/
@@ -668,8 +650,7 @@ struct x86_pmu {
pebs_broken :1,
pebs_prec_dist :1,
pebs_no_tlb :1,
- pebs_no_isolation :1,
- pebs_no_xmm_regs :1;
+ pebs_no_isolation :1;
int pebs_record_size;
int pebs_buffer_size;
int max_pebs_events;
diff --git a/arch/x86/include/uapi/asm/perf_regs.h b/arch/x86/include/uapi/asm/perf_regs.h
index ac67bbea10ca..7c9d2bb3833b 100644
--- a/arch/x86/include/uapi/asm/perf_regs.h
+++ b/arch/x86/include/uapi/asm/perf_regs.h
@@ -52,4 +52,7 @@ enum perf_event_x86_regs {
/* These include both GPRs and XMMX registers */
PERF_REG_X86_XMM_MAX = PERF_REG_X86_XMM15 + 2,
};
+
+#define PERF_REG_EXTENDED_MASK (~((1ULL << PERF_REG_X86_XMM0) - 1))
+
#endif /* _ASM_X86_PERF_REGS_H */
diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c
index 07c30ee17425..bb7e1132290b 100644
--- a/arch/x86/kernel/perf_regs.c
+++ b/arch/x86/kernel/perf_regs.c
@@ -74,6 +74,9 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)
return regs_get_register(regs, pt_regs_offset[idx]);
}

+#define PERF_REG_X86_RESERVED (((1ULL << PERF_REG_X86_XMM0) - 1) & \
+ ~((1ULL << PERF_REG_X86_MAX) - 1))
+
#ifdef CONFIG_X86_32
#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_R8) | \
(1ULL << PERF_REG_X86_R9) | \
@@ -86,7 +89,7 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)

int perf_reg_validate(u64 mask)
{
- if (!mask || (mask & REG_NOSUPPORT))
+ if (!mask || (mask & (REG_NOSUPPORT | PERF_REG_X86_RESERVED)))
return -EINVAL;

return 0;
@@ -112,7 +115,7 @@ void perf_get_regs_user(struct perf_regs *regs_user,

int perf_reg_validate(u64 mask)
{
- if (!mask || (mask & REG_NOSUPPORT))
+ if (!mask || (mask & (REG_NOSUPPORT | PERF_REG_X86_RESERVED)))
return -EINVAL;

return 0;
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 0ab99c7b652d..2bca72f3028b 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -241,6 +241,7 @@ struct perf_event;
#define PERF_PMU_CAP_NO_INTERRUPT 0x01
#define PERF_PMU_CAP_NO_NMI 0x02
#define PERF_PMU_CAP_AUX_NO_SG 0x04
+#define PERF_PMU_CAP_EXTENDED_REGS 0x08
#define PERF_PMU_CAP_EXCLUSIVE 0x10
#define PERF_PMU_CAP_ITRACE 0x20
#define PERF_PMU_CAP_HETEROGENEOUS_CPUS 0x40
diff --git a/include/linux/perf_regs.h b/include/linux/perf_regs.h
index 476747456bca..2d12e97d5e7b 100644
--- a/include/linux/perf_regs.h
+++ b/include/linux/perf_regs.h
@@ -11,6 +11,11 @@ struct perf_regs {

#ifdef CONFIG_HAVE_PERF_REGS
#include <asm/perf_regs.h>
+
+#ifndef PERF_REG_EXTENDED_MASK
+#define PERF_REG_EXTENDED_MASK 0
+#endif
+
u64 perf_reg_value(struct pt_regs *regs, int idx);
int perf_reg_validate(u64 mask);
u64 perf_reg_abi(struct task_struct *task);
@@ -18,6 +23,9 @@ void perf_get_regs_user(struct perf_regs *regs_user,
struct pt_regs *regs,
struct pt_regs *regs_user_copy);
#else
+
+#define PERF_REG_EXTENDED_MASK 0
+
static inline u64 perf_reg_value(struct pt_regs *regs, int idx)
{
return 0;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index abbd4b3b96c2..f85929ce13be 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5005,6 +5005,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg)
if (perf_event_check_period(event, value))
return -EINVAL;

+ if (!event->attr.freq && (value & (1ULL << 63)))
+ return -EINVAL;
+
event_function_call(event, __perf_event_period, &value);

return 0;
@@ -5923,7 +5926,7 @@ static void perf_sample_regs_user(struct perf_regs *regs_user,
if (user_mode(regs)) {
regs_user->abi = perf_reg_abi(current);
regs_user->regs = regs;
- } else if (current->mm) {
+ } else if (!(current->flags & PF_KTHREAD)) {
perf_get_regs_user(regs_user, regs, regs_user_copy);
} else {
regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE;
@@ -10033,6 +10036,12 @@ void perf_pmu_unregister(struct pmu *pmu)
}
EXPORT_SYMBOL_GPL(perf_pmu_unregister);

+static inline bool has_extended_regs(struct perf_event *event)
+{
+ return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) ||
+ (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK);
+}
+
static int perf_try_init_event(struct pmu *pmu, struct perf_event *event)
{
struct perf_event_context *ctx = NULL;
@@ -10064,12 +10073,16 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event)
perf_event_ctx_unlock(event->group_leader, ctx);

if (!ret) {
+ if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) &&
+ has_extended_regs(event))
+ ret = -EOPNOTSUPP;
+
if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE &&
- event_has_any_exclude_flag(event)) {
- if (event->destroy)
- event->destroy(event);
+ event_has_any_exclude_flag(event))
ret = -EINVAL;
- }
+
+ if (ret && event->destroy)
+ event->destroy(event);
}

if (ret)
diff --git a/tools/arch/x86/include/uapi/asm/perf_regs.h b/tools/arch/x86/include/uapi/asm/perf_regs.h
index ac67bbea10ca..7c9d2bb3833b 100644
--- a/tools/arch/x86/include/uapi/asm/perf_regs.h
+++ b/tools/arch/x86/include/uapi/asm/perf_regs.h
@@ -52,4 +52,7 @@ enum perf_event_x86_regs {
/* These include both GPRs and XMMX registers */
PERF_REG_X86_XMM_MAX = PERF_REG_X86_XMM15 + 2,
};
+
+#define PERF_REG_EXTENDED_MASK (~((1ULL << PERF_REG_X86_XMM0) - 1))
+
#endif /* _ASM_X86_PERF_REGS_H */
diff --git a/tools/perf/arch/x86/include/perf_regs.h b/tools/perf/arch/x86/include/perf_regs.h
index b7cd91a9014f..b7321337d100 100644
--- a/tools/perf/arch/x86/include/perf_regs.h
+++ b/tools/perf/arch/x86/include/perf_regs.h
@@ -9,7 +9,6 @@
void perf_regs_load(u64 *regs);

#define PERF_REGS_MAX PERF_REG_X86_XMM_MAX
-#define PERF_XMM_REGS_MASK (~((1ULL << PERF_REG_X86_XMM0) - 1))
#ifndef HAVE_ARCH_X86_64_SUPPORT
#define PERF_REGS_MASK ((1ULL << PERF_REG_X86_32_MAX) - 1)
#define PERF_SAMPLE_REGS_ABI PERF_SAMPLE_REGS_ABI_32
diff --git a/tools/perf/arch/x86/util/perf_regs.c b/tools/perf/arch/x86/util/perf_regs.c
index 7886ca5263e3..3666c0076df9 100644
--- a/tools/perf/arch/x86/util/perf_regs.c
+++ b/tools/perf/arch/x86/util/perf_regs.c
@@ -277,7 +277,7 @@ uint64_t arch__intr_reg_mask(void)
.type = PERF_TYPE_HARDWARE,
.config = PERF_COUNT_HW_CPU_CYCLES,
.sample_type = PERF_SAMPLE_REGS_INTR,
- .sample_regs_intr = PERF_XMM_REGS_MASK,
+ .sample_regs_intr = PERF_REG_EXTENDED_MASK,
.precise_ip = 1,
.disabled = 1,
.exclude_kernel = 1,
@@ -293,7 +293,7 @@ uint64_t arch__intr_reg_mask(void)
fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
if (fd != -1) {
close(fd);
- return (PERF_XMM_REGS_MASK | PERF_REGS_MASK);
+ return (PERF_REG_EXTENDED_MASK | PERF_REGS_MASK);
}

return PERF_REGS_MASK;