CVE-2021-47305 dma-buf/sync_file: Don't leak fences on merge failure

In the Linux kernel, the following vulnerability has been resolved: dma-buf/syncfile: Don't leak fences on merge failure Each addfence call does a dmafenceget on the relevant fence. In the error path, we weren't calling dmafenceput so all those fences got leaked. Also, in the kreallocarray failur...