Commit-ID: 79c5fe6db8c70558d3a64959f55596d137ccc6e6 Gitweb: http://git.kernel.org/tip/79c5fe6db8c70558d3a64959f55596d137ccc6e6 Author: Elena Reshetova <[email protected]> AuthorDate: Tue, 21 Feb 2017 17:34:55 +0200 Committer: Arnaldo Carvalho de Melo <[email protected]> CommitDate: Fri, 3 Mar 2017 19:07:14 -0300
perf cgroup: Convert cgroup_sel.refcnt from atomic_t to refcount_t 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 <[email protected]> Signed-off-by: David Windsor <[email protected]> Signed-off-by: Hans Liljestrand <[email protected]> Signed-off-by: Kees Kook <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: [email protected] Cc: Andrew Morton <[email protected]> Cc: David Windsor <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Hans Liljestrand <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kees Kook <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Matija Glavinic Pecotic <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- 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 eafbf114..86399ed 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 31f8dcd..d91966b 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; };
