2013-04-14 15:21:05

by Ingo Molnar

[permalink] [raw]
Subject: [GIT PULL] perf fixes

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: c481420248c6730246d2a1b1773d5d7007ae0835 perf: Fix error return code

Misc fixlets.

Thanks,

Ingo

------------------>
Chen Gang (3):
perf: Fix strncpy() use, always make sure it's NUL terminated
perf: Fix strncpy() use, use strlcpy() instead of strncpy()
ftrace: Fix strncpy() use, use strlcpy() instead of strncpy()

Stephane Eranian (2):
perf/x86: Fix uninitialized pt_regs in intel_pmu_drain_bts_buffer()
perf: Fix ring_buffer perf_output_space() boundary calculation

Wei Yongjun (1):
perf: Fix error return code


arch/x86/kernel/cpu/perf_event_intel_ds.c | 3 ++-
kernel/events/core.c | 4 +++-
kernel/events/internal.h | 2 +-
kernel/events/ring_buffer.c | 22 ++++++++++++++++++----
kernel/trace/ftrace.c | 4 ++--
kernel/trace/trace.c | 4 ++--
6 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 826054a..f71c9f0 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -314,10 +314,11 @@ int intel_pmu_drain_bts_buffer(void)
if (top <= at)
return 0;

+ memset(&regs, 0, sizeof(regs));
+
ds->bts_index = ds->bts_buffer_base;

perf_sample_data_init(&data, 0, event->hw.last_period);
- regs.ip = 0;

/*
* Prepare a generic sample, i.e. fill in the invariant fields.
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 59412d0..7e0962e 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4737,7 +4737,8 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
} else {
if (arch_vma_name(mmap_event->vma)) {
name = strncpy(tmp, arch_vma_name(mmap_event->vma),
- sizeof(tmp));
+ sizeof(tmp) - 1);
+ tmp[sizeof(tmp) - 1] = '\0';
goto got_name;
}

@@ -5986,6 +5987,7 @@ skip_type:
if (pmu->pmu_cpu_context)
goto got_cpu_context;

+ ret = -ENOMEM;
pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context);
if (!pmu->pmu_cpu_context)
goto free_dev;
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index d56a64c..eb675c4 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -16,7 +16,7 @@ struct ring_buffer {
int page_order; /* allocation order */
#endif
int nr_pages; /* nr of data pages */
- int writable; /* are we writable */
+ int overwrite; /* can overwrite itself */

atomic_t poll; /* POLL_ for wakeups */

diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 23cb34f..97fddb0 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -18,12 +18,24 @@
static bool perf_output_space(struct ring_buffer *rb, unsigned long tail,
unsigned long offset, unsigned long head)
{
- unsigned long mask;
+ unsigned long sz = perf_data_size(rb);
+ unsigned long mask = sz - 1;

- if (!rb->writable)
+ /*
+ * check if user-writable
+ * overwrite : over-write its own tail
+ * !overwrite: buffer possibly drops events.
+ */
+ if (rb->overwrite)
return true;

- mask = perf_data_size(rb) - 1;
+ /*
+ * verify that payload is not bigger than buffer
+ * otherwise masking logic may fail to detect
+ * the "not enough space" condition
+ */
+ if ((head - offset) > sz)
+ return false;

offset = (offset - tail) & mask;
head = (head - tail) & mask;
@@ -212,7 +224,9 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags)
rb->watermark = max_size / 2;

if (flags & RING_BUFFER_WRITABLE)
- rb->writable = 1;
+ rb->overwrite = 0;
+ else
+ rb->overwrite = 1;

atomic_set(&rb->refcount, 1);

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 6893d5a..db14374 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3441,14 +3441,14 @@ static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata;

static int __init set_ftrace_notrace(char *str)
{
- strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE);
+ strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE);
return 1;
}
__setup("ftrace_notrace=", set_ftrace_notrace);

static int __init set_ftrace_filter(char *str)
{
- strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE);
+ strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE);
return 1;
}
__setup("ftrace_filter=", set_ftrace_filter);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4f1dade..3f5046a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -132,7 +132,7 @@ static char *default_bootup_tracer;

static int __init set_cmdline_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
+ strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = 1;
@@ -162,7 +162,7 @@ static char *trace_boot_options __initdata;

static int __init set_trace_boot_options(char *str)
{
- strncpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
+ strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
trace_boot_options = trace_boot_options_buf;
return 0;
}