[kbuild-all] Re: [PATCH] powerpc/rtas_flash: fix a potential buffer overflow

Hi Yi, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on powerpc/next] [also build test WARNING on v5.14-rc1 next-20210713] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Yi-Zhuang/powerpc-rtas_flash-fix... base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next config: powerpc-allyesconfig (attached as .config) compiler: powerpc64-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/0day-ci/linux/commit/546db7a99374dedd110a01801ad4456f5... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Yi-Zhuang/powerpc-rtas_flash-fix-a-potential-buffer-overflow/20210714-090314 git checkout 546db7a99374dedd110a01801ad4456f56170d4d # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): arch/powerpc/kernel/rtas_flash.c: In function 'get_validate_flash_msg': 472 | if ((args_buf->update_results >= VALIDATE_CUR_UNKNOWN) || | ^~ arch/powerpc/kernel/rtas_flash.c:476:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if' 476 | if (n >= msglen) { | ^~ vim +/if +472 arch/powerpc/kernel/rtas_flash.c ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 464 ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 465 static int get_validate_flash_msg(struct rtas_validate_flash_t *args_buf, a94a14720eaf55 arch/powerpc/kernel/rtas_flash.c Vasant Hegde 2013-05-07 466 char *msg, int msglen) ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 467 { ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 468 int n; ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 469 ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 470 if (args_buf->status >= VALIDATE_TMP_UPDATE) { ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 471 n = sprintf(msg, "%d\n", args_buf->update_results); ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 @472 if ((args_buf->update_results >= VALIDATE_CUR_UNKNOWN) || ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 473 (args_buf->update_results == VALIDATE_TMP_UPDATE)) a94a14720eaf55 arch/powerpc/kernel/rtas_flash.c Vasant Hegde 2013-05-07 474 n += snprintf(msg + n, msglen - n, "%s\n", a94a14720eaf55 arch/powerpc/kernel/rtas_flash.c Vasant Hegde 2013-05-07 475 args_buf->buf); 546db7a99374de arch/powerpc/kernel/rtas_flash.c Yi Zhuang 2021-07-14 476 if (n >= msglen) { 546db7a99374de arch/powerpc/kernel/rtas_flash.c Yi Zhuang 2021-07-14 477 n = msglen; 546db7a99374de arch/powerpc/kernel/rtas_flash.c Yi Zhuang 2021-07-14 478 printk(KERN_ERR "FLASH: msg too long.\n"); 546db7a99374de arch/powerpc/kernel/rtas_flash.c Yi Zhuang 2021-07-14 479 } ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 480 } else { ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 481 n = sprintf(msg, "%d\n", args_buf->status); ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 482 } ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 483 return n; ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 484 } ^1da177e4c3f41 arch/ppc64/kernel/rtas_flash.c Linus Torvalds 2005-04-16 485 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org