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| author | Elena Reshetova <elena.reshetova@intel.com> | 2017-05-02 10:16:05 -0400 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2017-05-02 10:16:05 -0400 |
| commit | bd120ded6a6af61ad342a8a95b36b64bd1e2f9e6 (patch) | |
| tree | 8e3c4a2e444669f6355c3ec69940f8489f5eecfd /kernel/audit_watch.c | |
| parent | 9d2378f8c8f1a3fcfab681fd90c139d90dca7b69 (diff) | |
| download | lwn-bd120ded6a6af61ad342a8a95b36b64bd1e2f9e6.tar.gz lwn-bd120ded6a6af61ad342a8a95b36b64bd1e2f9e6.zip | |
audit: convert audit_watch.count 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.
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>
[PM: fix subject line, add #include]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Diffstat (limited to 'kernel/audit_watch.c')
| -rw-r--r-- | kernel/audit_watch.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index e293165dd063..e0656bd63036 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -28,6 +28,7 @@ #include <linux/fsnotify_backend.h> #include <linux/namei.h> #include <linux/netlink.h> +#include <linux/refcount.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/security.h> @@ -46,7 +47,7 @@ */ struct audit_watch { - atomic_t count; /* reference count */ + refcount_t count; /* reference count */ dev_t dev; /* associated superblock device */ char *path; /* insertion path */ unsigned long ino; /* associated inode number */ @@ -111,12 +112,12 @@ static inline struct audit_parent *audit_find_parent(struct inode *inode) void audit_get_watch(struct audit_watch *watch) { - atomic_inc(&watch->count); + refcount_inc(&watch->count); } void audit_put_watch(struct audit_watch *watch) { - if (atomic_dec_and_test(&watch->count)) { + if (refcount_dec_and_test(&watch->count)) { WARN_ON(watch->parent); WARN_ON(!list_empty(&watch->rules)); kfree(watch->path); @@ -178,7 +179,7 @@ static struct audit_watch *audit_init_watch(char *path) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&watch->rules); - atomic_set(&watch->count, 1); + refcount_set(&watch->count, 1); watch->path = path; watch->dev = AUDIT_DEV_UNSET; watch->ino = AUDIT_INO_UNSET; |