[PATCH 07/18] net, atm: convert atm_dev.refcnt from atomic_t to refcount_t
From: Elena Reshetova <elena.reshetova@intel.com>
Date: 2017-03-17 11:14:05
Also in:
bridge, linux-hams, lkml, netdev
Subsystem:
atm, networking [general], the rest · Maintainers:
Chas Williams, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted> Signed-off-by: Kees Cook <redacted> Signed-off-by: David Windsor <redacted> --- include/linux/atmdev.h | 7 ++++--- net/atm/proc.c | 2 +- net/atm/resources.c | 2 +- 3 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/include/linux/atmdev.h b/include/linux/atmdev.h
index c1da539..2a87aea 100644
--- a/include/linux/atmdev.h
+++ b/include/linux/atmdev.h@@ -11,6 +11,7 @@ #include <linux/uio.h> #include <net/sock.h> #include <linux/atomic.h> +#include <linux/refcount.h> #include <uapi/linux/atmdev.h> #ifdef CONFIG_PROC_FS
@@ -158,7 +159,7 @@ struct atm_dev { struct k_atm_dev_stats stats; /* statistics */ char signal; /* signal status (ATM_PHY_SIG_*) */ int link_rate; /* link rate (default: OC3) */ - atomic_t refcnt; /* reference count */ + refcount_t refcnt; /* reference count */ spinlock_t lock; /* protect internal members */ #ifdef CONFIG_PROC_FS struct proc_dir_entry *proc_entry; /* proc entry */
@@ -261,13 +262,13 @@ static inline int atm_may_send(struct atm_vcc *vcc,unsigned int size) static inline void atm_dev_hold(struct atm_dev *dev) { - atomic_inc(&dev->refcnt); + refcount_inc(&dev->refcnt); } static inline void atm_dev_put(struct atm_dev *dev) { - if (atomic_dec_and_test(&dev->refcnt)) { + if (refcount_dec_and_test(&dev->refcnt)) { BUG_ON(!test_bit(ATM_DF_REMOVED, &dev->flags)); if (dev->ops->dev_close) dev->ops->dev_close(dev);
diff --git a/net/atm/proc.c b/net/atm/proc.c
index bbb6461..bcb8ee5 100644
--- a/net/atm/proc.c
+++ b/net/atm/proc.c@@ -61,7 +61,7 @@ static void atm_dev_info(struct seq_file *seq, const struct atm_dev *dev) add_stats(seq, "0", &dev->stats.aal0); seq_puts(seq, " "); add_stats(seq, "5", &dev->stats.aal5); - seq_printf(seq, "\t[%d]", atomic_read(&dev->refcnt)); + seq_printf(seq, "\t[%d]", refcount_read(&dev->refcnt)); seq_putc(seq, '\n'); }
diff --git a/net/atm/resources.c b/net/atm/resources.c
index 0447d5d..9182447 100644
--- a/net/atm/resources.c
+++ b/net/atm/resources.c@@ -109,7 +109,7 @@ struct atm_dev *atm_dev_register(const char *type, struct device *parent, else memset(&dev->flags, 0, sizeof(dev->flags)); memset(&dev->stats, 0, sizeof(dev->stats)); - atomic_set(&dev->refcnt, 1); + refcount_set(&dev->refcnt, 1); if (atm_proc_dev_register(dev) < 0) { pr_err("atm_proc_dev_register failed for dev %s\n", type);
--
2.7.4