staging: ion: Prevent incorrect reference counting behavour
Supply additional checks in order to prevent unexpected results.
Fixes: b892bf75b2034 ("ion: Switch ion to use dma-buf")
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index 806e9b3..aac9b38 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -489,6 +489,9 @@ static void *ion_buffer_kmap_get(struct ion_buffer *buffer)
void *vaddr;
if (buffer->kmap_cnt) {
+ if (buffer->kmap_cnt == INT_MAX)
+ return ERR_PTR(-EOVERFLOW);
+
buffer->kmap_cnt++;
return buffer->vaddr;
}
@@ -509,6 +512,9 @@ static void *ion_handle_kmap_get(struct ion_handle *handle)
void *vaddr;
if (handle->kmap_cnt) {
+ if (handle->kmap_cnt == INT_MAX)
+ return ERR_PTR(-EOVERFLOW);
+
handle->kmap_cnt++;
return buffer->vaddr;
}
