etmem scan: fix memleak in vm_idle_read

euleros inclusion
category: feature
feature: etmem
bugzilla: https://gitee.com/openeuler/kernel/issues/I4OODH?from=project-issue
CVE: NA

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free pic before return from vm_idle_read in etmem scan
Signed-off-by: NKemeng Shi <shikemeng@huawei.com>
Reviewed-by: Nlouhongxiang <louhongxiang@huawei.com>
Reviewed-by: NChen Wandun <chenwandun@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

fs/proc/etmem_scan.c

@@ -891,6 +891,7 @@ static ssize_t vm_idle_read(struct file *file, char *buf,
 	ret = pic->bytes_copied;
 	*ppos = pic->next_hva;
 out_kvm:
+	kfree(pic);
 	return ret;
 
 }