Em Tue, Feb 21, 2017 at 05:35:02PM +0200, Elena Reshetova escreveu:
> 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.
You forgot this one, fixing it...
@@ -1439,7 +1439,7 @@ static void __machine__remove_thread(struct machine
*machine, struct thread *th,
if (machine->last_match == th)
machine->last_match = NULL;
- BUG_ON(atomic_read(&th->refcnt) == 0);
+ BUG_ON(refcount_read(&th->refcnt) == 0);
if (lock)
pthread_rwlock_wrlock(&machine->threads_lock);
rb_erase_init(&th->rb_node, &machine->threads);
[acme@jouet linux]$
> Signed-off-by: Elena Reshetova <elena.reshet...@intel.com>
> Signed-off-by: Hans Liljestrand <ishkam...@gmail.com>
> Signed-off-by: Kees Cook <keesc...@chromium.org>
> Signed-off-by: David Windsor <dwind...@gmail.com>
> ---
> tools/perf/util/thread.c | 6 +++---
> tools/perf/util/thread.h | 4 ++--
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
> index f5af87f..74e79d2 100644
> --- a/tools/perf/util/thread.c
> +++ b/tools/perf/util/thread.c
> @@ -53,7 +53,7 @@ struct thread *thread__new(pid_t pid, pid_t tid)
> goto err_thread;
>
> list_add(&comm->list, &thread->comm_list);
> - atomic_set(&thread->refcnt, 1);
> + refcount_set(&thread->refcnt, 1);
> RB_CLEAR_NODE(&thread->rb_node);
> }
>
> @@ -88,13 +88,13 @@ void thread__delete(struct thread *thread)
> struct thread *thread__get(struct thread *thread)
> {
> if (thread)
> - atomic_inc(&thread->refcnt);
> + refcount_inc(&thread->refcnt);
> return thread;
> }
>
> void thread__put(struct thread *thread)
> {
> - if (thread && atomic_dec_and_test(&thread->refcnt)) {
> + if (thread && refcount_dec_and_test(&thread->refcnt)) {
> /*
> * Remove it from the dead_threads list, as last reference
> * is gone.
> diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
> index 99263cb..e571885 100644
> --- a/tools/perf/util/thread.h
> +++ b/tools/perf/util/thread.h
> @@ -1,7 +1,7 @@
> #ifndef __PERF_THREAD_H
> #define __PERF_THREAD_H
>
> -#include <linux/atomic.h>
> +#include <linux/refcount.h>
> #include <linux/rbtree.h>
> #include <linux/list.h>
> #include <unistd.h>
> @@ -23,7 +23,7 @@ struct thread {
> pid_t tid;
> pid_t ppid;
> int cpu;
> - atomic_t refcnt;
> + refcount_t refcnt;
> char shortname[3];
> bool comm_set;
> int comm_len;
> --
> 2.7.4
