diff options
| author | Leo Yan <leo.yan@linaro.org> | 2019-04-28 16:32:27 +0800 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2019-05-02 16:00:20 -0400 |
| commit | 35bb59c10a6d0578806dd500477dae9cb4be344e (patch) | |
| tree | dff9b39a2bea7bfded12b37bc6c15ade5bfe37e1 | |
| parent | cf0c37b6dbf74fb71bea07b516612d29e00dcbc4 (diff) | |
perf cs-etm: Always allocate memory for cs_etm_queue::prev_packet
Robert Walker reported a segmentation fault is observed when process
CoreSight trace data; this issue can be easily reproduced by the command
'perf report --itrace=i1000i' for decoding tracing data.
If neither the 'b' flag (synthesize branches events) nor 'l' flag
(synthesize last branch entries) are specified to option '--itrace',
cs_etm_queue::prev_packet will not been initialised. After merging the
code to support exception packets and sample flags, there introduced a
number of uses of cs_etm_queue::prev_packet without checking whether it
is valid, for these cases any accessing to uninitialised prev_packet
will cause crash.
As cs_etm_queue::prev_packet is used more widely now and it's already
hard to follow which functions have been called in a context where the
validity of cs_etm_queue::prev_packet has been checked, this patch
always allocates memory for cs_etm_queue::prev_packet.
Reported-by: Robert Walker <robert.walker@arm.com>
Suggested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Fixes: 7100b12cf474 ("perf cs-etm: Generate branch sample for exception packet")
Fixes: 24fff5eb2b93 ("perf cs-etm: Avoid stale branch samples when flush packet")
Link: http://lkml.kernel.org/r/20190428083228.20246-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| -rw-r--r-- | tools/perf/util/cs-etm.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index 7777cfc1ad8c..de488b43f440 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -422,11 +422,9 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm) if (!etmq->packet) goto out_free; - if (etm->synth_opts.last_branch || etm->sample_branches) { - etmq->prev_packet = zalloc(szp); - if (!etmq->prev_packet) - goto out_free; - } + etmq->prev_packet = zalloc(szp); + if (!etmq->prev_packet) + goto out_free; if (etm->synth_opts.last_branch) { size_t sz = sizeof(struct branch_stack); |