Messages in this thread | | | Date | Fri, 28 Jul 2023 22:18:06 +0300 | Subject | Re: [PATCH 1/1] perf dlfilter: Initialize addr_location before passing it to thread__find_symbol_fb() | From | Adrian Hunter <> |
| |
On 27/07/23 17:13, Arnaldo Carvalho de Melo wrote: > Em Tue, Jul 25, 2023 at 02:51:58PM +0300, Adrian Hunter escreveu: >> On 25/07/23 00:31, Arnaldo Carvalho de Melo wrote: >>> Em Mon, Jul 24, 2023 at 02:16:05PM -0700, Ian Rogers escreveu: >>>> On Mon, Jul 24, 2023 at 2:09 PM Arnaldo Carvalho de Melo >>>> <acme@kernel.org> wrote: >>>>> >>>>> As thread__find_symbol_fb() will end up calling thread__find_map() and >>>>> it in turn will call these on uninitialized memory: >>>>> >>>>> maps__zput(al->maps); >>>>> map__zput(al->map); >>>>> thread__zput(al->thread); >>>> >>>> Normally there would be a addr_location__exit. It looks here like most >>>> values are copied in al_to_d_al, which copies reference counted values >>>> without doing appropriate gets. Perhaps add the gets in al_to_d_al and >>>> add the exit to make it clear there can't be addr_location related >>>> leaks here. > > Or just make al_to_d_al use strdups for the strings it gets from > reference counter structs. > > That or make the caller of ->resolve_address() provide a initialized > addr_location that it then exits.
OK, I will send a patch.
> > - Arnaldo > >>> I'll do that as well and add the addr_location__exit() then send a V2. >> >> The data is not valid outside the context of ->filter_event() or >> ->filter_event_early(), so the reference counts should not be changed. >> That probably needs to be made clearer in the documentation. > > > >>> >>> - Arnaldo >>> >>>> Thanks, >>>> Ian >>>> >>>>> Fixes: 0dd5041c9a0eaf8c ("perf addr_location: Add init/exit/copy functions") >>>>> Cc: Adrian Hunter <adrian.hunter@intel.com> >>>>> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> >>>>> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> >>>>> Cc: Disha Goel <disgoel@linux.vnet.ibm.com> >>>>> Cc: Ian Rogers <irogers@google.com> >>>>> Cc: Jiri Olsa <jolsa@kernel.org> >>>>> Cc: Kajol Jain <kjain@linux.ibm.com> >>>>> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> >>>>> Cc: Namhyung Kim <namhyung@kernel.org> >>>>> Link: https://lore.kernel.org/lkml/ >>>>> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> >>>>> --- >>>>> tools/perf/util/dlfilter.c | 1 + >>>>> 1 file changed, 1 insertion(+) >>>>> >>>>> diff --git a/tools/perf/util/dlfilter.c b/tools/perf/util/dlfilter.c >>>>> index 46f74b2344dbb34c..798a53d7e6c9dfc5 100644 >>>>> --- a/tools/perf/util/dlfilter.c >>>>> +++ b/tools/perf/util/dlfilter.c >>>>> @@ -166,6 +166,7 @@ static __s32 dlfilter__resolve_address(void *ctx, __u64 address, struct perf_dlf >>>>> if (!thread) >>>>> return -1; >>>>> >>>>> + addr_location__init(&al); >>>>> thread__find_symbol_fb(thread, d->sample->cpumode, address, &al); >>>>> >>>>> al_to_d_al(&al, &d_al); >>>>> -- >>>>> 2.37.1 >>>>> >>> >> >
| |