[PATCH 8/8] tools, perf: Add asprintf replacement

From: Andi Kleen
Date: Mon Sep 15 2014 - 20:21:03 EST


From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

asprintf corrupts memory on some older glibc versions.
Provide a replacement. This fixes various segfaults
with --branch-history on older Fedoras.

Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
---
tools/perf/Makefile.perf | 1 +
tools/perf/builtin-report.c | 3 ++-
tools/perf/util/asprintf.c | 28 ++++++++++++++++++++++++++++
3 files changed, 31 insertions(+), 1 deletion(-)
create mode 100644 tools/perf/util/asprintf.c

diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 95e832b..255fe0b 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -376,6 +376,7 @@ LIB_OBJS += $(OUTPUT)util/vdso.o
LIB_OBJS += $(OUTPUT)util/stat.o
LIB_OBJS += $(OUTPUT)util/record.o
LIB_OBJS += $(OUTPUT)util/srcline.o
+LIB_OBJS += $(OUTPUT)util/asprintf.o
LIB_OBJS += $(OUTPUT)util/data.o
LIB_OBJS += $(OUTPUT)util/tsc.o
LIB_OBJS += $(OUTPUT)util/cloexec.o
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index f72a6c4..9bb6194 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -754,7 +754,8 @@ repeat:
callchain_param.branch_callstack = 1;
callchain_param.key = CCKEY_ADDRESS;
symbol_conf.use_callchain = true;
- callchain_register_param(&callchain_param);
+ if (callchain_register_param(&callchain_param) < 0)
+ pr_err("Cannot register callchain parameters");
if (sort_order == default_sort_order)
sort_order = "srcline,symbol,dso";
branch_mode = 0;
diff --git a/tools/perf/util/asprintf.c b/tools/perf/util/asprintf.c
new file mode 100644
index 0000000..9aafaca
--- /dev/null
+++ b/tools/perf/util/asprintf.c
@@ -0,0 +1,28 @@
+/* Replacement for asprintf as it's buggy in older glibc versions */
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+
+int vasprintf(char **str, const char *fmt, va_list ap)
+{
+ char buf[1024];
+ int len = vsnprintf(buf, sizeof buf, fmt, ap);
+
+ *str = malloc(len + 1);
+ if (!*str)
+ return -1;
+ strcpy(*str, buf);
+ return len;
+}
+
+int asprintf(char **str, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = vasprintf(str, fmt, ap);
+ va_end(ap);
+ return ret;
+}
--
1.9.3

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