Re: [PATCH 3/4] pci-arbiter: Fix a -Wstringop-truncation warning

[James Clarke]

On 3 Nov 2019, at 16:20, Samuel Thibault <samuel.thibault@gnu.org> wrote:
> 
> Hello,
> 
> Joan Lledó via Bug reports for the GNU Hurd, le dim. 03 nov. 2019 10:38:28 
> +0100, a ecrit:
>> * pci-arbiter/pcifs.c:
>>        * create_dir_entry:
>>              Limit to NAME_SIZE-1 when calling strncpy().
>>              Finish entry->name with '\0'.
>>        * create_fs_tree:
>>              memset() to 0 the directory entry.
>>              Limit to NAME_SIZE-1 all calls to
>>               snprintf() and strncpy().
> 
> Applied, thanks!
> 
>> @@ -206,7 +208,7 @@ create_fs_tree (struct pcifs * fs)
>>        e_stat = list->stat;
>>        e_stat.st_mode &= ~S_IROOT;   /* Remove the root mode */
>>        memset (entry_name, 0, NAME_SIZE);
>> -      snprintf (entry_name, NAME_SIZE, "%04x", device->domain);
>> +      snprintf (entry_name, NAME_SIZE - 1, "%04x", device->domain);
> 
> Perhaps replace the whole memset with just setting
> entry_name[NAME_SIZE-1] = 0
> ? and ditto below.

snprintf guarantees NUL termination, so this now over-truncates.

James