Merge tag 'perf-urgent-for-mingo-4.14-20171027' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

- Fix memory corruption in the annotation routines because of zero
  length symbols (asm ones) (Ravi Bangoria)

- Fix printing garbage as an error message when re-running the
  lexer events matcher (Jiri Olsa)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 17 insertions, 3 deletions

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 4397a8b6e6cd..aa66791b1bfc 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -606,9 +606,19 @@ static struct arch *arch__find(const char *name)
 int symbol__alloc_hist(struct symbol *sym)
 {
 	struct annotation *notes = symbol__annotation(sym);
-	const size_t size = symbol__size(sym);
+	size_t size = symbol__size(sym);
 	size_t sizeof_sym_hist;
 
+	/*
+	 * Add buffer of one element for zero length symbol.
+	 * When sample is taken from first instruction of
+	 * zero length symbol, perf still resolves it and
+	 * shows symbol name in perf report and allows to
+	 * annotate it.
+	 */
+	if (size == 0)
+		size = 1;
+
 	/* Check for overflow when calculating sizeof_sym_hist */
 	if (size > (SIZE_MAX - sizeof(struct sym_hist)) / sizeof(struct sym_hist_entry))
 		return -1;
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index dcfdafdc2f1c..6680e4fb7967 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -154,6 +154,10 @@ do {							\
 	yycolumn += yyleng;				\
 } while (0);
 
+#define USER_REJECT		\
+	yycolumn -= yyleng;	\
+	REJECT
+
 %}
 
 %x mem
@@ -335,8 +339,8 @@ r{num_raw_hex}		{ return raw(yyscanner); }
 {num_hex}		{ return value(yyscanner, 16); }
 
 {modifier_event}	{ return str(yyscanner, PE_MODIFIER_EVENT); }
-{bpf_object}		{ if (!isbpf(yyscanner)) REJECT; return str(yyscanner, PE_BPF_OBJECT); }
-{bpf_source}		{ if (!isbpf(yyscanner)) REJECT; return str(yyscanner, PE_BPF_SOURCE); }
+{bpf_object}		{ if (!isbpf(yyscanner)) USER_REJECT; return str(yyscanner, PE_BPF_OBJECT); }
+{bpf_source}		{ if (!isbpf(yyscanner)) USER_REJECT; return str(yyscanner, PE_BPF_SOURCE); }
 {name}			{ return pmu_str_check(yyscanner); }
 "/"			{ BEGIN(config); return '/'; }
 -			{ return '-'; }