Hi Tianjia,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on integrity/next-integrity]
[also build test ERROR on v5.6 next-20200408]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Tianjia-Zhang/support-to-read-and-tune-appraise-mode-in-runtime/20200409-114057
base:   https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git next-integrity
config: c6x-randconfig-a001-20200409 (attached as .config)
compiler: c6x-elf-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=9.3.0 make.cross ARCH=c6x 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   security/integrity/ima/ima_fs.c: In function 'repopulate_ima_appraise_mode':
>> security/integrity/ima/ima_fs.c:518:9: error: implicit declaration of function 'verify_pkcs7_signature' [-Werror=implicit-function-declaration]
     518 |   ret = verify_pkcs7_signature(s, strlen(s), pkcs7, pkcs7_len,
         |         ^~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors

vim +/verify_pkcs7_signature +518 security/integrity/ima/ima_fs.c

   499	
   500	/* Verify the supplied PKCS#7 signature. The signed content may be off,
   501	 * enforce, log, fix.
   502	 */
   503	static int repopulate_ima_appraise_mode(void *pkcs7, size_t pkcs7_len)
   504	{
   505		static char *appraise_mode_strings[] = { "off", "enforce", "fix", "log" };
   506		static int appraise_modes[] = {
   507			0,
   508			IMA_APPRAISE_ENFORCE,
   509			IMA_APPRAISE_FIX,
   510			IMA_APPRAISE_LOG,
   511		};
   512		int index, ret = -1;
   513		const char *s;
   514		int size = ARRAY_SIZE(appraise_mode_strings);
   515	
   516		for (index = 0; index < size; index++) {
   517			s = appraise_mode_strings[index];
 > 518			ret = verify_pkcs7_signature(s, strlen(s), pkcs7, pkcs7_len,
   519						    NULL, VERIFYING_UNSPECIFIED_SIGNATURE,
   520						    NULL, NULL);
   521			if (!ret)
   522				break;
   523		}
   524	
   525		if (index == size)
   526			goto out;
   527	
   528		ima_appraise = appraise_modes[index];
   529	
   530	out:
   531		return ret;
   532	}
   533	

---
0-DAY CI Kernel Test Service, Intel Corporation
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