[PATCH v4 0/3] perf/core: Check sample_type in sample data saving helper functions

From: Yabin Cui
Date: Fri May 10 2024 - 15:14:48 EST


Hello,

We use helper functions to save raw data, callchain and branch stack in
perf_sample_data. These functions update perf_sample_data->dyn_size without
checking event->attr.sample_type, which may result in unused space allocated in
sample records. To prevent this from happening, this patchset enforces checking
sample_type of an event in these helper functions.

Thanks,
Yabin


Changes since v1:
- Check event->attr.sample_type & PERF_SAMPLE_RAW before
calling perf_sample_save_raw_data().
- Subject has been changed to reflect the change of solution.

Changes since v2:
- Move sample_type check into perf_sample_save_raw_data().
- (New patch) Move sample_type check into perf_sample_save_callchain().
- (New patch) Move sample_type check into perf_sample_save_brstack().

Changes since v3:
- Fix -Werror=implicit-function-declaration by moving has_branch_stack().

Original commit message from v1:
perf/core: Trim dyn_size if raw data is absent

Original commit message from v2/v3:
perf/core: Save raw sample data conditionally based on sample type

Yabin Cui (3):
perf/core: Save raw sample data conditionally based on sample type
perf/core: Check sample_type in perf_sample_save_callchain
perf/core: Check sample_type in perf_sample_save_brstack

arch/s390/kernel/perf_cpum_cf.c | 2 +-
arch/s390/kernel/perf_pai_crypto.c | 2 +-
arch/s390/kernel/perf_pai_ext.c | 2 +-
arch/x86/events/amd/core.c | 3 +--
arch/x86/events/amd/ibs.c | 5 ++---
arch/x86/events/core.c | 3 +--
arch/x86/events/intel/ds.c | 9 +++-----
include/linux/perf_event.h | 20 ++++++++++++-----
kernel/events/core.c | 35 +++++++++++++++---------------
kernel/trace/bpf_trace.c | 11 +++++-----
10 files changed, 49 insertions(+), 43 deletions(-)

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2.45.0.118.g7fe29c98d7-goog