### What this PR does / why we need it?
Resolved a double-free memory vulnerability in the pooling layer under
re-computation scenarios.
### Does this PR introduce _any_ user-facing change?
### How was this patch tested?
- vLLM version: v0.13.0
- vLLM main:
d68209402d
Signed-off-by: fems14 <1804143737@qq.com>