From ac5e7f84c0e050fe19146d9bf51f69890beabcef Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Thu, 5 Dec 2013 19:26:42 +0100 Subject: [PATCH] perf symbols: Fix bug in usage of the basename() function The basename() implementation varies a lot between systems. The Linux man page says: "basename may modify the content of the path, so it may be desirable to pass a copy when calling the function". On some other systems, the returned address may come from an internal buffer which can be reused in subsequent calls, thus the results should also be copied. The dso__set_basename() function was not doing this causing problems on some systems with wrong library names being shown by perf report, such as on Android systems. This patch fixes the problem. The patch is relative to tip.git. In v2, we clean up the comments based on Ingo's feedback. Reported-by: Ben Cheng Signed-off-by: Stephane Eranian Acked-by: Ingo Molnar Cc: Ben Cheng Cc: David Ahern Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20131205182642.GA14614@quad [ v3: Fixed up wrt allocated flag now being set in dso__set_short_name ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/dso.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c index 582b5d344aa3..436922f1f9d9 100644 --- a/tools/perf/util/dso.c +++ b/tools/perf/util/dso.c @@ -413,7 +413,28 @@ void dso__set_short_name(struct dso *dso, const char *name, bool name_allocated) static void dso__set_basename(struct dso *dso) { - dso__set_short_name(dso, basename((char *)dso->long_name), false); + /* + * basename() may modify path buffer, so we must pass + * a copy. + */ + char *base, *lname = strdup(dso->long_name); + + if (!lname) + return; + + /* + * basename() may return a pointer to internal + * storage which is reused in subsequent calls + * so copy the result. + */ + base = strdup(basename(lname)); + + free(lname); + + if (!base) + return; + + dso__set_short_name(dso, base, true); } int dso__name_len(const struct dso *dso)