Re: [dpdk-dev] [PATCH] power: fix use-after-free in pstate code

[David Hunt <david.hunt@intel.com>]

Hi Anatoly,

On 7/4/2021 4:56 PM, Anatoly Burakov wrote:
> Previous fix has addressed the incorrect handling of `base_frequency`
> file, but has added a use-after-free error due to the fact that all
> further code paths will lead to an `fclose()` call at the end, so the
> additional `fclose()` call right after processing the file was
> unnecessary.
>
> Coverity issue: 369901
>
> Fixes: 8a5febaac4f7 ("power: fix P-state base frequency handling")
>
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> ---
>   lib/librte_power/power_pstate_cpufreq.c | 1 -
>   1 file changed, 1 deletion(-)
>
> diff --git a/lib/librte_power/power_pstate_cpufreq.c b/lib/librte_power/power_pstate_cpufreq.c
> index 1cb0e4d917..ec745153d3 100644
> --- a/lib/librte_power/power_pstate_cpufreq.c
> +++ b/lib/librte_power/power_pstate_cpufreq.c
> @@ -220,7 +220,6 @@ power_init_for_setting_freq(struct pstate_power_info *pi)
>   
>   		base_ratio = strtoul(buf_base, NULL, POWER_CONVERT_TO_DECIMAL)
>   				/ BUS_FREQ;
> -		fclose(f_base);
>   	}
>   
>   	/* Add MSR read to detect turbo status */


Yes, removing the fclose will do it. Either that or add an "f_base = 
NULL" after the fclose, but the fclose removal is fine.

Acked-by: David Hunt <david.hunt@intel.com>