message: fix CircularBuffer ashmem fallback
diff: @@ -90,19 +90,24 @@ void* CircularBuffer::alloc(size_t size) noexcept {
  if (UTILS_UNLIKELY(mUsesAshmem < 0)) {
  // ashmem failed
  - if (vaddr_guard != MAP_FAILED)
  + if (vaddr_guard != MAP_FAILED) {
  munmap(vaddr_guard, size);
  + }
  - if (vaddr_shadow != MAP_FAILED)
  + if (vaddr_shadow != MAP_FAILED) {
  munmap(vaddr_shadow, size);
  + }
  - if (vaddr != MAP_FAILED)
  + if (vaddr != MAP_FAILED) {
  munmap(vaddr, size);
  + }
  - if (fd >= 0)
  + if (fd >= 0) {
  close(fd);
  + }
  - data = mmap(nullptr, size * 2 + BLOCK_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  + data = mmap(nullptr, size * 2 + BLOCK_SIZE,
  + PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  ASSERT_POSTCONDITION(data,
  "couldn't allocate %u KiB of virtual address space for the command buffer",
  