kernel: ext4: fix slab-use-after-free in ext4_split_extent_at()

In the Linux kernel, the following vulnerability has been resolved: ext4: fix slab-use-after-free in ext4splitextentat We hit the following use-after-free: ================================================================== BUG: KASAN: slab-use-after-free in ext4splitextentat+0xba8/0xcc0 Read of...