path: root/ipc
diff options
authorElena Reshetova <elena.reshetova@intel.com>2017-09-08 16:17:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-08 18:26:51 -0700
commitf74370b86ec1e0ee8a56ba838efe78e21d8dba23 (patch)
tree5ecda3120c2c13915cf8e1d2ee570062465479ef /ipc
parenta2e0602c36ed9fe042714694dd5a889ecd8cb556 (diff)
ipc: convert sem_undo_list.refcnt from atomic_t to refcount_t
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. Link: http://lkml.kernel.org/r/1499417992-3238-3-git-send-email-elena.reshetova@intel.com 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> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Serge Hallyn <serge@hallyn.com> Cc: <arozansk@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc')
1 files changed, 4 insertions, 4 deletions
diff --git a/ipc/sem.c b/ipc/sem.c
index c6c50370504c..31b138b9e756 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -122,7 +122,7 @@ struct sem_undo {
* that may be shared among all a CLONE_SYSVSEM task group.
struct sem_undo_list {
- atomic_t refcnt;
+ refcount_t refcnt;
spinlock_t lock;
struct list_head list_proc;
@@ -1642,7 +1642,7 @@ static inline int get_undo_list(struct sem_undo_list **undo_listp)
if (undo_list == NULL)
return -ENOMEM;
- atomic_set(&undo_list->refcnt, 1);
+ refcount_set(&undo_list->refcnt, 1);
current->sysvsem.undo_list = undo_list;
@@ -2041,7 +2041,7 @@ int copy_semundo(unsigned long clone_flags, struct task_struct *tsk)
error = get_undo_list(&undo_list);
if (error)
return error;
- atomic_inc(&undo_list->refcnt);
+ refcount_inc(&undo_list->refcnt);
tsk->sysvsem.undo_list = undo_list;
} else
tsk->sysvsem.undo_list = NULL;
@@ -2070,7 +2070,7 @@ void exit_sem(struct task_struct *tsk)
tsk->sysvsem.undo_list = NULL;
- if (!atomic_dec_and_test(&ulp->refcnt))
+ if (!refcount_dec_and_test(&ulp->refcnt))
for (;;) {