Re: [PATCH] dm-crypt: remove ineffective comparison

[Baoquan He <bhe@redhat.com>]

CC Coiby,

On 10/01/25 at 05:32pm, Suchit Karunakaran wrote:
> In restore_dm_crypt_keys_to_thread_keyring(), key_count is a global
> variable declared as unsigned int. The comparison key_count < 0
> is therefore always false and has no effect.
> Remove the dead comparison to make the code clearer and
> silence static analysis warnings.
> 
> Found by Coverity: CID#1649028
> 
> Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com>
> ---
>  kernel/crash_dump_dm_crypt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/crash_dump_dm_crypt.c b/kernel/crash_dump_dm_crypt.c
> index 401423ba477d..39cfc13ff350 100644
> --- a/kernel/crash_dump_dm_crypt.c
> +++ b/kernel/crash_dump_dm_crypt.c
> @@ -115,7 +115,7 @@ static int restore_dm_crypt_keys_to_thread_keyring(void)
>  
>  	addr = dm_crypt_keys_addr;
>  	dm_crypt_keys_read((char *)&key_count, sizeof(key_count), &addr);
> -	if (key_count < 0 || key_count > KEY_NUM_MAX) {
> +	if (key_count > KEY_NUM_MAX) {

Sounds reasonable to me,

Acked-by: Baoquan He <bhe@redhat.com>

>  		kexec_dprintk("Failed to read the number of dm-crypt keys\n");
>  		return -1;
>  	}
> -- 
> 2.51.0
>