PM / devfreq: hisi: Fix potential UAF in OPP handling

Ensure all required data is acquired before calling dev_pm_opp_put(opp)
to maintain correct resource acquisition and release order.

Fixes: 7da2fdaaa1e6 ("PM / devfreq: Add HiSilicon uncore frequency scaling driver")
Signed-off-by: Pengjie Zhang <zhangpengjie2@huawei.com>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Link: https://patchwork.kernel.org/project/linux-pm/patch/20250915062135.748653-1-zhangpengjie2@huawei.com/

diff --git a/drivers/devfreq/hisi_uncore_freq.c b/drivers/devfreq/hisi_uncore_freq.c
index b8e4621c57ebc76513e4eba978aa54f2b884e210..4d00d813c8ac614ab5ffc3476ed382a392b2676e 100644 (file)
--- a/drivers/devfreq/hisi_uncore_freq.c
+++ b/drivers/devfreq/hisi_uncore_freq.c
@@ -264,10 +264,11 @@ static int hisi_uncore_target(struct device *dev, unsigned long *freq,
                dev_err(dev, "Failed to get opp for freq %lu hz\n", *freq);
                return PTR_ERR(opp);
        }
-       dev_pm_opp_put(opp);
 
        data = (u32)(dev_pm_opp_get_freq(opp) / HZ_PER_MHZ);
 
+       dev_pm_opp_put(opp);
+
        return hisi_uncore_cmd_send(uncore, HUCF_PCC_CMD_SET_FREQ, &data);
 }