From: Elena Reshetova <elena.reshet...@intel.com> The refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter.
This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshet...@intel.com> Signed-off-by: David Windsor <dwind...@gmail.com> Signed-off-by: Hans Liljestrand <ishkam...@gmail.com> Signed-off-by: Kees Kook <keesc...@chromium.org> Tested-by: Arnaldo Carvalho de Melo <a...@redhat.com> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> Cc: alsa-de...@alsa-project.org Cc: Andrew Morton <a...@linux-foundation.org> Cc: David Windsor <dwind...@gmail.com> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Hans Liljestrand <ishkam...@gmail.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Kees Kook <keesc...@chromium.org> Cc: Mark Rutland <mark.rutl...@arm.com> Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic....@nokia.com> Cc: Peter Zijlstra <pet...@infradead.org> Link: http://lkml.kernel.org/r/1487691303-31858-2-git-send-email-elena.reshet...@intel.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/cgroup.c | 6 +++--- tools/perf/util/cgroup.h | 4 ++-- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c index eafbf11442b2..86399eda3684 100644 --- a/tools/perf/util/cgroup.c +++ b/tools/perf/util/cgroup.c @@ -127,19 +127,19 @@ static int add_cgroup(struct perf_evlist *evlist, char *str) goto found; n++; } - if (atomic_read(&cgrp->refcnt) == 0) + if (refcount_read(&cgrp->refcnt) == 0) free(cgrp); return -1; found: - atomic_inc(&cgrp->refcnt); + refcount_inc(&cgrp->refcnt); counter->cgrp = cgrp; return 0; } void close_cgroup(struct cgroup_sel *cgrp) { - if (cgrp && atomic_dec_and_test(&cgrp->refcnt)) { + if (cgrp && refcount_dec_and_test(&cgrp->refcnt)) { close(cgrp->fd); zfree(&cgrp->name); free(cgrp); diff --git a/tools/perf/util/cgroup.h b/tools/perf/util/cgroup.h index 31f8dcdbd7ef..d91966b97cbd 100644 --- a/tools/perf/util/cgroup.h +++ b/tools/perf/util/cgroup.h @@ -1,14 +1,14 @@ #ifndef __CGROUP_H__ #define __CGROUP_H__ -#include <linux/atomic.h> +#include <linux/refcount.h> struct option; struct cgroup_sel { char *name; int fd; - atomic_t refcnt; + refcount_t refcnt; }; -- 2.9.3
