From: Elena Reshetova <elena.reshetova@intel.com>
To: linux-kernel@vger.kernel.org
Cc: cgroups@vger.kernel.org, linux-audit@redhat.com,
linux-fsdevel@vger.kernel.org, peterz@infradead.org,
gregkh@linuxfoundation.org, viro@zeniv.linux.org.uk,
tj@kernel.org, mingo@redhat.com, hannes@cmpxchg.org,
lizefan@huawei.com, acme@kernel.org,
alexander.shishkin@linux.intel.com, paul@paul-moore.com,
eparis@redhat.com, akpm@linux-foundation.org, arnd@arndb.de,
luto@kernel.org, Elena Reshetova <elena.reshetova@intel.com>,
Hans Liljestrand <ishkamiel@gmail.com>,
Kees Cook <keescook@chromium.org>,
David Windsor <dwindsor@gmail.com>
Subject: [PATCH 07/19] kernel: convert ring_buffer.refcount from atomic_t to refcount_t
Date: Mon, 20 Feb 2017 12:18:56 +0200 [thread overview]
Message-ID: <1487585948-6401-8-git-send-email-elena.reshetova@intel.com> (raw)
In-Reply-To: <1487585948-6401-1-git-send-email-elena.reshetova@intel.com>
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.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
---
kernel/events/core.c | 4 ++--
kernel/events/internal.h | 3 ++-
kernel/events/ring_buffer.c | 2 +-
3 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 07a778b..e1c337d 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5039,7 +5039,7 @@ struct ring_buffer *ring_buffer_get(struct perf_event *event)
rcu_read_lock();
rb = rcu_dereference(event->rb);
if (rb) {
- if (!atomic_inc_not_zero(&rb->refcount))
+ if (!refcount_inc_not_zero(&rb->refcount))
rb = NULL;
}
rcu_read_unlock();
@@ -5049,7 +5049,7 @@ struct ring_buffer *ring_buffer_get(struct perf_event *event)
void ring_buffer_put(struct ring_buffer *rb)
{
- if (!atomic_dec_and_test(&rb->refcount))
+ if (!refcount_dec_and_test(&rb->refcount))
return;
WARN_ON_ONCE(!list_empty(&rb->event_list));
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index 486fd78..b8e6fdf 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -3,13 +3,14 @@
#include <linux/hardirq.h>
#include <linux/uaccess.h>
+#include <linux/refcount.h>
/* Buffer handling */
#define RING_BUFFER_WRITABLE 0x01
struct ring_buffer {
- atomic_t refcount;
+ refcount_t refcount;
struct rcu_head rcu_head;
#ifdef CONFIG_PERF_USE_VMALLOC
struct work_struct work;
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 257fa46..8de1664 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -284,7 +284,7 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags)
else
rb->overwrite = 1;
- atomic_set(&rb->refcount, 1);
+ refcount_set(&rb->refcount, 1);
INIT_LIST_HEAD(&rb->event_list);
spin_lock_init(&rb->event_lock);
--
2.7.4
next prev parent reply other threads:[~2017-02-20 10:24 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-20 10:18 [PATCH 00/19] Kernel subsystem refcounter conversions Elena Reshetova
2017-02-20 10:18 ` [PATCH 01/19] kernel: convert sighand_struct.count from atomic_t to refcount_t Elena Reshetova
2017-02-20 12:30 ` kbuild test robot
2017-02-20 12:42 ` kbuild test robot
2017-02-20 10:18 ` [PATCH 02/19] kernel: convert signal_struct.sigcnt " Elena Reshetova
2017-02-20 10:18 ` [PATCH 03/19] kernel: convert user_struct.__count " Elena Reshetova
2017-02-20 10:18 ` [PATCH 04/19] kernel: convert task_struct.usage " Elena Reshetova
2017-02-20 10:18 ` [PATCH 05/19] kernel: convert task_struct.stack_refcount " Elena Reshetova
2017-02-20 10:18 ` [PATCH 06/19] kernel: convert perf_event_context.refcount " Elena Reshetova
2017-02-20 10:28 ` Peter Zijlstra
2017-02-20 12:14 ` Reshetova, Elena
2017-02-20 10:18 ` Elena Reshetova [this message]
2017-02-20 10:18 ` [PATCH 08/19] kernel: convert ring_buffer.aux_refcount " Elena Reshetova
2017-02-20 10:18 ` [PATCH 09/19] kernel: convert uprobe.ref " Elena Reshetova
2017-02-20 10:18 ` [PATCH 10/19] kernel: convert nsproxy.count " Elena Reshetova
2017-02-20 10:19 ` [PATCH 11/19] kernel: convert cgroup_namespace.count " Elena Reshetova
2017-03-06 19:55 ` Tejun Heo
2017-02-20 10:19 ` [PATCH 12/19] kernel: convert css_set.refcount " Elena Reshetova
2017-03-06 19:54 ` Tejun Heo
2017-03-07 19:12 ` Reshetova, Elena
2017-03-07 19:21 ` Tejun Heo
2017-02-20 10:19 ` [PATCH 13/19] kernel: convert group_info.usage " Elena Reshetova
2017-02-20 10:19 ` [PATCH 14/19] kernel: convert cred.usage " Elena Reshetova
2017-02-20 10:19 ` [PATCH 15/19] kernel: convert audit_tree.count " Elena Reshetova
2017-02-20 22:07 ` Paul Moore
2017-02-21 7:15 ` Reshetova, Elena
2017-02-28 22:11 ` Paul Moore
2017-03-01 0:16 ` Kees Cook
2017-03-01 19:35 ` Paul Moore
2017-03-01 23:04 ` Kees Cook
2017-04-11 19:01 ` Paul Moore
2017-04-18 6:33 ` Reshetova, Elena
2017-02-20 10:19 ` [PATCH 16/19] kernel: convert audit_watch.count " Elena Reshetova
2017-02-20 10:19 ` [PATCH 17/19] kernel: convert numa_group.refcount " Elena Reshetova
2017-02-20 10:19 ` [PATCH 18/19] kernel: convert futex_pi_state.refcount " Elena Reshetova
2017-02-20 10:19 ` [PATCH 19/19] kernel: convert kcov.refcount " Elena Reshetova
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