From: Daniel Rosenberg drosen@google.com
If a user happens to call ION_IOC_FREE during an ION_IOC_ALLOC on the just allocated id, and the copy_to_user fails, the cleanup code will attempt to free an already freed handle.
This adds a wrapper for ion_alloc that adds an ion_handle_get to avoid this.
Signed-off-by: Daniel Rosenberg drosen@google.com Signed-off-by: Dennis Cagle d-cagle@codeaurora.org Signed-off-by: Patrick Daly pdaly@codeaurora.org Signed-off-by: Lee Jones lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/staging/android/ion/ion-ioctl.c | 14 +++++++++----- drivers/staging/android/ion/ion.c | 15 ++++++++++++--- drivers/staging/android/ion/ion.h | 4 ++++ 3 files changed, 25 insertions(+), 8 deletions(-)
--- a/drivers/staging/android/ion/ion-ioctl.c +++ b/drivers/staging/android/ion/ion-ioctl.c @@ -96,10 +96,10 @@ long ion_ioctl(struct file *filp, unsign { struct ion_handle *handle;
- handle = ion_alloc(client, data.allocation.len, - data.allocation.align, - data.allocation.heap_id_mask, - data.allocation.flags); + handle = __ion_alloc(client, data.allocation.len, + data.allocation.align, + data.allocation.heap_id_mask, + data.allocation.flags, true); if (IS_ERR(handle)) return PTR_ERR(handle);
@@ -174,10 +174,14 @@ long ion_ioctl(struct file *filp, unsign
if (dir & _IOC_READ) { if (copy_to_user((void __user *)arg, &data, _IOC_SIZE(cmd))) { - if (cleanup_handle) + if (cleanup_handle) { ion_free(client, cleanup_handle); + ion_handle_put(cleanup_handle); + } return -EFAULT; } } + if (cleanup_handle) + ion_handle_put(cleanup_handle); return ret; } --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -401,9 +401,9 @@ static int ion_handle_add(struct ion_cli return 0; }
-struct ion_handle *ion_alloc(struct ion_client *client, size_t len, - size_t align, unsigned int heap_id_mask, - unsigned int flags) +struct ion_handle *__ion_alloc(struct ion_client *client, size_t len, + size_t align, unsigned int heap_id_mask, + unsigned int flags, bool grab_handle) { struct ion_handle *handle; struct ion_device *dev = client->dev; @@ -453,6 +453,8 @@ struct ion_handle *ion_alloc(struct ion_ return handle;
mutex_lock(&client->lock); + if (grab_handle) + ion_handle_get(handle); ret = ion_handle_add(client, handle); mutex_unlock(&client->lock); if (ret) { @@ -462,6 +464,13 @@ struct ion_handle *ion_alloc(struct ion_
return handle; } + +struct ion_handle *ion_alloc(struct ion_client *client, size_t len, + size_t align, unsigned int heap_id_mask, + unsigned int flags) +{ + return __ion_alloc(client, len, align, heap_id_mask, flags, false); +} EXPORT_SYMBOL(ion_alloc);
void ion_free_nolock(struct ion_client *client, --- a/drivers/staging/android/ion/ion.h +++ b/drivers/staging/android/ion/ion.h @@ -109,6 +109,10 @@ struct ion_handle *ion_alloc(struct ion_ size_t align, unsigned int heap_id_mask, unsigned int flags);
+struct ion_handle *__ion_alloc(struct ion_client *client, size_t len, + size_t align, unsigned int heap_id_mask, + unsigned int flags, bool grab_handle); + /** * ion_free - free a handle * @client: the client