Validate the BTF entry count and individual data sizes when reading
HEADER_BPF_BTF from perf.data files to prevent excessive memory
allocation from malformed files.
Reuses the MAX_BPF_PROGS (131072) and MAX_BPF_DATA_LEN (256 MB)
limits from HEADER_BPF_PROG_INFO processing.
Cc: Song Liu <song@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add validation to process_bpf_prog_info() to harden against malformed
perf.data files:
- Upper bound on BPF program count (max 131072)
- Upper bound on per-program data_len (max 256MB)
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add upper bound checks in PMU capabilities processing to harden against
malformed perf.data files:
- nr_pmu bounded to MAX_PMU_MAPPINGS (4096) in process_pmu_caps()
- nr_pmu_caps bounded to MAX_PMU_CAPS (512) in __process_pmu_caps()
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add upper bound check on nr_nodes in process_hybrid_topology() to
harden against malformed perf.data files (reuses MAX_PMU_MAPPINGS,
4096).
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add upper bound check on cache entry count in process_cache() to harden
against malformed perf.data files (max 32768).
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add upper bound check on nr_groups in process_group_desc() to harden
against malformed perf.data files (max 32768), and move the env
assignment after validation.
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add upper bound check on pmu_num in process_pmu_mappings() to harden
against malformed perf.data files (max 4096).
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add validation to process_mem_topology() to harden against malformed
perf.data files:
- Upper bound check on nr_nodes (reuses MAX_NUMA_NODES, 4096)
- Minimum section size check before allocating
This is particularly important here since nr is u64, making unbounded
values especially dangerous.
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add validation to process_numa_topology() to harden against malformed
perf.data files:
- Upper bound check on nr_nodes (max 4096)
- Minimum section size check before allocating
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add validation to process_cpu_topology() to harden against malformed
perf.data files:
- Verify nr_cpus_avail was initialized (HEADER_NRCPUS processed first)
- Bounds check sibling counts (cores, threads, dies) against nr_cpus_avail
- Fix two bare 'return -1' that leaked env->cpu by using 'goto free_cpu'
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
While working on some cleanups sashiko questioned about pre-existing
issues, namely lacking sanity checks for perf.data headers, add some
with the help of Claude.
Cc: Ian Rogers <irogers@google.com>
Cc: Swapnil Sapkal <swapnil.sapkal@amd.com>
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Further validate the HEADER_CPU_DOMAIN_INFO fields, this time checking
the nr_domains field.
Assisted-by: Claude Code:claude-opus-4-6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Instead of using zalloc(nr_entries * sizeof_entry) that is what calloc()
does.
In some places where linux/zalloc.h isn't needed, remove it, add when
needed and was getting it indirectly.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
As suggested in an unrelated sashiko review:
https://sashiko.dev/#/patchset/20260407195145.2372104-1-acme%40kernel.org
"
Could a malformed perf.data file provide out-of-bounds values for cpu and
domain?
These variables are read directly from the file and used as indices for
cd_map and cd_map[cpu]->domains without any validation against
env->nr_cpus_avail or max_sched_domains.
Similar to the issue above, this is an existing lack of validation that
becomes apparent when looking at the allocation boundaries.
"
Validate it.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Sashiko suggests we use some reasonable max number of args to avoid
overflows when reading perf.data files, do it.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Store cacheline size during perf record in header, so that cacheline
size can be used for other features, like sort keys for perf report.
Testing example with feat enabled:
$ perf record ./Example
$ perf report --header-only | grep -C 3 cacheline
CPU_DOMAIN_INFO info available, use -I to display
e_machine : 62
e_flags : 0
cacheline size: 64
missing features: TRACING_DATA BUILD_ID BRANCH_STACK GROUP_DESC AUXTRACE \
STAT CLOCKID DIR_FORMAT COMPRESSED CLOCK_DATA
========
[namhyung: Update the commit message and remove blank lines]
Signed-off-by: Ricky Ringler <ricky.ringler@proton.me>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
In non-pipe/data mode the header has a 256-bit bitmap representing
whether a feature is enabled or not. In pipe mode features are written
out in perf_event__synthesize_features as PERF_RECORD_HEADER_FEATURE
events with a special zero sized marker for the last feature. If a new
feature is added the last feature marker event appears as that feature
from old pipe mode perf data. As the event is zero sized it will fail
to be processed and generally terminate perf.
Add a last_feat variable to the header that in non-pipe/data mode is
just HEADER_LAST_FEATURE. In pipe mode compute the last_feat by
handling zero sized feature events, assuming they are the marker and
updating last_feat accordingly. Potentially a feature event could be
zero sized and so still process the feature event, just ignore the
error if it fails.
As perf_event__process_feature can properly handle pipe mode data,
migrate users to it except for report that still wants to group events
and stop header printing with the last feature marker. Make
perf_event__process_feature non-fatal in the case of a newer feature
than this version of perf's HEADER_LAST_FEATURE, which was the
behavior all users wanted.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
By removing the features from feat_ops with ifdefs the previous logic
would print "# (null)" when perf processed a feature that lacked
builtin support. Remove the ifdefs from feat_ops and in the relevant
functions print errors/messages about the lack of support.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
For logging and debug messages it can be convenient to convert a
feature number to a name. Add header_feat__name for this and reuse the
data already within the feat_ops struct.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The build_id parsing functions calculate a filename length from the
event header size and read directly into a stack buffer of PATH_MAX
bytes without bounds checking. A malformed perf.data file with a
crafted header.size can cause the length to be negative or exceed
PATH_MAX, resulting in a stack buffer overflow.
Add bounds checking for the filename length in both
perf_header__read_build_ids() and the ABI quirk variant. Print a
warning message when invalid length is detected.
Signed-off-by: SeungJu Cheon <suunj1331@gmail.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The live mode works similar to simple `perf stat` command, by profiling
the target and printing results on the terminal as soon as the target
finishes.
Example usage:
# perf sched stats -- true
Description
----------------------------------------------------------------------------------------------------
DESC -> Description of the field
COUNT -> Value of the field
PCT_CHANGE -> Percent change with corresponding base value
AVG_JIFFIES -> Avg time in jiffies between two consecutive occurrence of event
----------------------------------------------------------------------------------------------------
Time elapsed (in jiffies) : 1
----------------------------------------------------------------------------------------------------
CPU: <ALL CPUS SUMMARY>
----------------------------------------------------------------------------------------------------
DESC COUNT PCT_CHANGE
----------------------------------------------------------------------------------------------------
yld_count : 0
array_exp : 0
sched_count : 0
sched_goidle : 0 ( 0.00% )
ttwu_count : 0
ttwu_local : 0 ( 0.00% )
rq_cpu_time : 27875
run_delay : 0 ( 0.00% )
pcount : 0
----------------------------------------------------------------------------------------------------
CPU: <ALL CPUS SUMMARY> | DOMAIN: SMT
----------------------------------------------------------------------------------------------------
DESC COUNT AVG_JIFFIES
----------------------------------------- <Category busy> ------------------------------------------
busy_lb_count : 0 $ 0.00 $
busy_lb_balanced : 0 $ 0.00 $
busy_lb_failed : 0 $ 0.00 $
busy_lb_imbalance_load : 0
busy_lb_imbalance_util : 0
busy_lb_imbalance_task : 0
busy_lb_imbalance_misfit : 0
busy_lb_gained : 0
busy_lb_hot_gained : 0
busy_lb_nobusyq : 0 $ 0.00 $
busy_lb_nobusyg : 0 $ 0.00 $
*busy_lb_success_count : 0
*busy_lb_avg_pulled : 0.00
... and so on. Output will show similar data for all the cpus in the
system.
Co-developed-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: James Clark <james.clark@linaro.org>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anubhav Shelat <ashelat@redhat.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: David Vernet <void@manifault.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Gautham Shenoy <gautham.shenoy@amd.com>
Cc: Graham Woodward <graham.woodward@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Cc: Shrikanth Hegde <sshegde@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Yujie Liu <yujie.liu@intel.com>
Cc: Zhongqiu Han <quic_zhonhan@quicinc.com>
[ Avoid potentially using 'sv' uninitialized by calling free_cpu_domain_info() only when build_cpu_domain_map() is called ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>