!3955 drm/radeon: possible buffer overflow

Merge Pull Request from: @ci-robot 
 
PR sync from: Dapeng Yu <dapeng.yu@windriver.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/TLGC6SVGWOHQEQZU734B72OKKP5LTCTL/ 
 
https://gitee.com/openeuler/kernel/issues/I8AS5P 
 
Link:https://gitee.com/openeuler/kernel/pulls/3955

 

Reviewed-by: sanglipeng <sanglipeng1@jd.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>