use-after-free in amdgpu/amdgpu_cs.c

../util_double_list.h:119:39: error: pointer 'sem' used after 'free' [-Werror=use-after-free]
  119 |         pos = container_of(pos->member.next, pos, member))
      |                                       ^
../util_double_list.h:112:23: note: in definition of macro 'container_of'
  112 |     (void *)((char *)(ptr)                                              \
      |                       ^~~
../amdgpu/amdgpu_cs.c:144:33: note: in expansion of macro 'LIST_FOR_EACH_ENTRY'
  144 |                                 LIST_FOR_EACH_ENTRY(sem, &context->sem_list[i][j][k], list) {
      |                                 ^~~~~~~~~~~~~~~~~~~
In function 'amdgpu_cs_unreference_sem',
    inlined from 'amdgpu_cs_ctx_free' at ../subprojects/libdrm/amdgpu/amdgpu_cs.c:147:6:
../amdgpu/amdgpu_cs.c:663:17: note: call to 'free' here
  663 |                 free(sem);
      |                 ^~~~~~~~~