Jessica,
On 2017/5/31 11:48, Wanlong Gao wrote:
>
>
> On 2017/5/31 11:30, Jessica Yu wrote:
>> +++ Wanlong Gao [31/05/17 10:23 +0800]:
>>> Hi Jessica,
>>>
>>> On 2017/5/29 17:10, Jessica Yu wrote:
>>>> +++ Xie XiuQi [20/05/17 15:46 +0800]:
>>>>> From: Wanlong Gao <gaowanl...@huawei.com>
>>>>>
>>>>> Module name has a limited length, but currently the build system
>>>>> allows the build finishing even if the module name is too long.
>>>>>
>>>>> CC
>>>>> /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.o
>>>>> /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.c:9:2:
>>>>> warning: initializer-string for array of chars is too long [enabled by
>>>>> default]
>>>>> .name = KBUILD_MODNAME,
>>>>> ^
>>>>>
>>>>> but it's merely a warning.
>>>>>
>>>>> This patch adds the check of the module name length in modpost and stops
>>>>> the build properly.
>>>>>
>>>>> Signed-off-by: Wanlong Gao <gaowanl...@huawei.com>
>>>>> Signed-off-by: Xie XiuQi <xiexi...@huawei.com>
>>>>> ---
>>>>> scripts/mod/modpost.c | 11 +++++++++++
>>>>> 1 file changed, 11 insertions(+)
>>>>>
>>>>> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
>>>>> index 30d752a..db11c57 100644
>>>>> --- a/scripts/mod/modpost.c
>>>>> +++ b/scripts/mod/modpost.c
>>>>> @@ -2166,6 +2166,17 @@ static int add_versions(struct buffer *b, struct
>>>>> module *mod)
>>>>> {
>>>>> struct symbol *s, *exp;
>>>>> int err = 0;
>>>>> + const char *mod_name;
>>>>> +
>>>>> + mod_name = strrchr(mod->name, '/');
>>>>> + if (mod_name == NULL)
>>>>> + mod_name = mod->name;
>>>>> + else
>>>>> + mod_name++;
>>>>> + if (strlen(mod_name) >= MODULE_NAME_LEN) {
>>>>> + merror("module name is too long [%s.ko]\n", mod->name);
>>>>> + return 1;
>>>>> + }
>>>>
>>>> Hi Xie,
>>>>
>>>> This check shouldn't be in add_versions() (which does something else
>>>> entirely),
>>>> it should probably be put in a separate helper function called from main.
>>>> But
>>>> I'm not a big fan of the extra string manipulation to do something this
>>>> simple.
>>>>
>>>> I think this check can be vastly simplified, how about something like the
>>>> following?
>>>
>>> This looks better, would you apply your following patch?
>>>
>>> Reviewed-by: Wanlong Gao <gaowanl...@huawei.com>
>>> Tested-by: Wanlong Gao <gaowanl...@huawei.com>
>>
>> Sure, thanks for testing. I'll go ahead and format this into a proper
>> patch and resend.
>
> Please wait, I just found that this patch makes the built module can't
> be inserted by the following error:
>
> # insmod abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabc.ko
> insmod: ERROR: could not insert module
> abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabc.ko: Invalid parameters
>
> # dmesg
> abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabc: Unknown symbol
> __fentry__ (err -22)
>
>
Any idea about this error?
Thanks,
Wanlong Gao
> Thanks,
> Wanlong Gao
>
>>
>> Jessica
>>
>>>>
>>>> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
>>>> index 48397fe..bb09fc7 100644
>>>> --- a/scripts/mod/modpost.c
>>>> +++ b/scripts/mod/modpost.c
>>>> @@ -2139,6 +2139,9 @@ static void add_header(struct buffer *b, struct
>>>> module *mod)
>>>> "#endif\n");
>>>> buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
>>>> buf_printf(b, "};\n");
>>>> + buf_printf(b, "\n");
>>>> + buf_printf(b, "static void __attribute__((section(\".discard\"),
>>>> used)) __modname_test(void)\n");
>>>> + buf_printf(b, "{ BUILD_BUG_ON(sizeof(KBUILD_MODNAME) >
>>>> MODULE_NAME_LEN); }\n");
>>>> }
>>>>
>>>> static void add_intree_flag(struct buffer *b, int is_intree)
>>>>
>>>> This simply checks if KBUILD_MODNAME > MODULE_NAME_LEN and breaks the
>>>> build if
>>>> it does.
>>>>
>>>> Jessica
>>>>
>>>>> for (s = mod->unres; s; s = s->next) {
>>>>> exp = find_symbol(s->name);
>>>>> --
>>>>> 1.8.3.1
>>>>>
>>>>
>>>> .
>>>>
>>>
>>
>> .
>>
>
>
> .
>
