perf probe: Fix possible double free on error

A double free occurred when get source file path failed. If lr->path
failed to assign a new value, it will be freed as the old path and then
be freed again during line_range__clear(), and causes this:

  $ perf probe -L do_execve -k vmlinux
  *** Error in `/usr/bin/perf': double free or corruption (fasttop):
      0x0000000000a9ac50 ***
  ======= Backtrace: =========
  ../lib64/libc.so.6(+0x6eeef)[0x7ffff5e44eef]
  ../lib64/libc.so.6(+0x78cae)[0x7ffff5e4ecae]
  ../lib64/libc.so.6(+0x79987)[0x7ffff5e4f987]
  ../bin/perf[0x4ab41f]
  ...

This patch fix this problem.

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425463302-1687-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
He Kuang 2015-03-04 18:01:42 +08:00 committed by Arnaldo Carvalho de Melo
parent 443a70541c
commit a78604deff
1 changed files with 5 additions and 1 deletions

View File

@ -790,7 +790,11 @@ static int __show_line_range(struct line_range *lr, const char *module,
/* Convert source file path */
tmp = lr->path;
ret = get_real_path(tmp, lr->comp_dir, &lr->path);
free(tmp); /* Free old path */
/* Free old path when new path is assigned */
if (tmp != lr->path)
free(tmp);
if (ret < 0) {
pr_warning("Failed to find source file path.\n");
return ret;