[PATCH 11/29] drivers, media: convert cx88_core.refcount from atomic_t to refcount_t
From: Elena Reshetova <elena.reshetova@intel.com>
Date: 2017-03-06 14:27:30
Also in:
linux-bcache, linux-media, linux-pci, linux-raid, linux-s390, linux-scsi, linux-serial, lkml
Subsystem:
cx88 video4linux driver, media input infrastructure (v4l/dvb), the rest · Maintainers:
Mauro Carvalho Chehab, 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> --- drivers/media/pci/cx88/cx88-cards.c | 2 +- drivers/media/pci/cx88/cx88-core.c | 4 ++-- drivers/media/pci/cx88/cx88.h | 3 ++- 3 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/media/pci/cx88/cx88-cards.c b/drivers/media/pci/cx88/cx88-cards.c
index cdfbde2..7fc5f5f 100644
--- a/drivers/media/pci/cx88/cx88-cards.c
+++ b/drivers/media/pci/cx88/cx88-cards.c@@ -3670,7 +3670,7 @@ struct cx88_core *cx88_core_create(struct pci_dev *pci, int nr) if (!core) return NULL; - atomic_inc(&core->refcount); + refcount_set(&core->refcount, 1); core->pci_bus = pci->bus->number; core->pci_slot = PCI_SLOT(pci->devfn); core->pci_irqmask = PCI_INT_RISC_RD_BERRINT | PCI_INT_RISC_WR_BERRINT |
diff --git a/drivers/media/pci/cx88/cx88-core.c b/drivers/media/pci/cx88/cx88-core.c
index 973a9cd4..8bfa5b7 100644
--- a/drivers/media/pci/cx88/cx88-core.c
+++ b/drivers/media/pci/cx88/cx88-core.c@@ -1052,7 +1052,7 @@ struct cx88_core *cx88_core_get(struct pci_dev *pci) mutex_unlock(&devlist); return NULL; } - atomic_inc(&core->refcount); + refcount_inc(&core->refcount); mutex_unlock(&devlist); return core; }
@@ -1073,7 +1073,7 @@ void cx88_core_put(struct cx88_core *core, struct pci_dev *pci) release_mem_region(pci_resource_start(pci, 0), pci_resource_len(pci, 0)); - if (!atomic_dec_and_test(&core->refcount)) + if (!refcount_dec_and_test(&core->refcount)) return; mutex_lock(&devlist);
diff --git a/drivers/media/pci/cx88/cx88.h b/drivers/media/pci/cx88/cx88.h
index 115414c..16c1313 100644
--- a/drivers/media/pci/cx88/cx88.h
+++ b/drivers/media/pci/cx88/cx88.h@@ -24,6 +24,7 @@ #include <linux/i2c-algo-bit.h> #include <linux/videodev2.h> #include <linux/kdev_t.h> +#include <linux/refcount.h> #include <media/v4l2-device.h> #include <media/v4l2-fh.h>
@@ -339,7 +340,7 @@ struct cx8802_dev; struct cx88_core { struct list_head devlist; - atomic_t refcount; + refcount_t refcount; /* board name */ int nr;
--
2.7.4