From: Lee Jones lee.jones@linaro.org
pass_to_user() eventually calls kref_put() on an ION handle which is still live, potentially allowing for it to be legitimately freed by the client.
Prevent this from happening before its final use in both ION_IOC_ALLOC and ION_IOC_IMPORT.
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 | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
--- a/drivers/staging/android/ion/ion-ioctl.c +++ b/drivers/staging/android/ion/ion-ioctl.c @@ -165,10 +165,9 @@ long ion_ioctl(struct file *filp, unsign data.allocation.flags, true); if (IS_ERR(handle)) return PTR_ERR(handle); - pass_to_user(handle); data.allocation.handle = handle->id; - cleanup_handle = handle; + pass_to_user(handle); break; } case ION_IOC_FREE: @@ -212,11 +211,12 @@ long ion_ioctl(struct file *filp, unsign if (IS_ERR(handle)) { ret = PTR_ERR(handle); } else { + data.handle.handle = handle->id; handle = pass_to_user(handle); - if (IS_ERR(handle)) + if (IS_ERR(handle)) { ret = PTR_ERR(handle); - else - data.handle.handle = handle->id; + data.handle.handle = 0; + } } break; }