perf parse-events: Fix incorrect conversion of 'if () free()' to 'zfree()'

When applying a patch by Ian I incorrectly converted to zfree() an
expression that involved testing some other struct member, not the one
being freed, which lead to bugs reproduceable by:

  $ perf stat -e i/bs,tsc,L2/o sleep 1
  WARNING: multiple event parsing errors
  Segmentation fault (core dumped)
  $

Fix it by restoring the test for pos->free_str before freeing
pos->val.str, but continue using zfree(&pos->val.str) to set that member
to NULL after freeing it.

Reported-by: Ian Rogers <[email protected]>
Fixes: e8dfb81838b1 ("perf parse-events: Fix memory leaks found on parse_events")
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: [email protected]
Cc: Jiri Olsa <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

0 files changed, 0 insertions, 0 deletions