On Tue, May 28, 2019 at 8:04 AM Arnaldo Carvalho de Melo <arnaldo.m...@gmail.com> wrote: > > Em Mon, May 27, 2019 at 05:46:26PM -0500, Shawn Landden escreveu: > > On Mon, May 27, 2019 at 5:38 PM Arnaldo Carvalho de Melo > > <a...@kernel.org> wrote: > > > > > > From: Shawn Landden <sh...@git.icu> > > > > > > This strncat() is safe because the buffer was allocated with zalloc(), > > > however gcc doesn't know that. Since the string always has 4 non-null > > > bytes, just use memcpy() here. > > > > > > CC /home/shawn/linux/tools/perf/util/data-convert-bt.o > > > In file included from /usr/include/string.h:494, > > > from > > > /home/shawn/linux/tools/lib/traceevent/event-parse.h:27, > > > from util/data-convert-bt.c:22: > > > In function ‘strncat’, > > > inlined from ‘string_set_value’ at util/data-convert-bt.c:274:4: > > > /usr/include/powerpc64le-linux-gnu/bits/string_fortified.h:136:10: > > > error: ‘__builtin_strncat’ output may be truncated copying 4 bytes from a > > > string of length 4 [-Werror=stringop-truncation] > > > 136 | return __builtin___strncat_chk (__dest, __src, __len, __bos > > > (__dest)); > > > | > > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > Signed-off-by: Shawn Landden <sh...@git.icu> > > > Cc: Adrian Hunter <adrian.hun...@intel.com> > > > Cc: Jiri Olsa <jo...@redhat.com> > > > Cc: Namhyung Kim <namhy...@kernel.org> > > > Cc: Wang Nan <wangn...@huawei.com> > > > LPU-Reference: 20190518183238.10954-1-sh...@git.icu > > > Link: > > > https://lkml.kernel.org/n/tip-289f1jice17ta7tr3tstm...@git.kernel.org > > > Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> > > > --- > > > tools/perf/util/data-convert-bt.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tools/perf/util/data-convert-bt.c > > > b/tools/perf/util/data-convert-bt.c > > > index e0311c9750ad..9097543a818b 100644 > > > --- a/tools/perf/util/data-convert-bt.c > > > +++ b/tools/perf/util/data-convert-bt.c > > > @@ -271,7 +271,7 @@ static int string_set_value(struct bt_ctf_field > > > *field, const char *string) > > > if (i > 0) > > > strncpy(buffer, string, i); > > > } > > > - strncat(buffer + p, numstr, 4); > > > + memcpy(buffer + p, numstr, 4); > > I took care to have enough context in my patch that you could see what > > was going on. I wonder if there is a way to make that care > > propate when people add Signed-off-by: lines. > > I just checked and the patch is the same, the description I only changed > the subject line, so that when one uses: Functionally, yes. However look at how my version has enough context that you can immediately know that the patch is correct (instead of the default of 5 lines): https://www.spinics.net/lists/linux-perf-users/msg08563.html
> > git log --oneline > > we can know what is the component and what kind of build failure was > that. > > - Arnaldo > > > > p += 3; > > > } > > > } > > > -- > > > 2.20.1 > > > > > -- > > - Arnaldo
