tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 196d330d7fb1e7cc0d85641c89ce4602cb36f12e commit: 281d0c962752fb40866dd8d4cade68656f34bd1f [4926/7526] fortify: Add Clang support config: x86_64-randconfig-a001 (https://download.01.org/0day-ci/archive/20220224/202202240750.ZC6gMTEp-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project d271fc04d5b97b12e6b797c6067d3c96a8d7470e) 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://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=281d0c962752fb40866dd8d4cade68656f34bd1f git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 281d0c962752fb40866dd8d4cade68656f34bd1f # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/spi/ net/core/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): In file included from net/core/flow_dissector.c:3: In file included from include/linux/skbuff.h:15: In file included from include/linux/time.h:60: In file included from include/linux/time32.h:13: In file included from include/linux/timex.h:65: In file included from arch/x86/include/asm/timex.h:5: In file included from arch/x86/include/asm/processor.h:22: In file included from arch/x86/include/asm/msr.h:11: In file included from arch/x86/include/asm/cpumask.h:5: In file included from include/linux/cpumask.h:12: In file included from include/linux/bitmap.h:11: In file included from include/linux/string.h:253: >> include/linux/fortify-string.h:336:4: warning: call to __read_overflow2_field declared with 'warning' attribute: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Wattribute-warning] __read_overflow2_field(q_size_field, size); ^ 1 warning generated. vim +/warning +336 include/linux/fortify-string.h 28e77cc1c06866 Kees Cook 2021-06-16 267 28e77cc1c06866 Kees Cook 2021-06-16 268 /* 28e77cc1c06866 Kees Cook 2021-06-16 269 * __builtin_object_size() must be captured here to avoid evaluating argument 28e77cc1c06866 Kees Cook 2021-06-16 270 * side-effects further into the macro layers. 28e77cc1c06866 Kees Cook 2021-06-16 271 */ 28e77cc1c06866 Kees Cook 2021-06-16 272 #define memset(p, c, s) __fortify_memset_chk(p, c, s, \ 28e77cc1c06866 Kees Cook 2021-06-16 273 __builtin_object_size(p, 0), __builtin_object_size(p, 1)) a28a6e860c6cf2 Francis Laniel 2021-02-25 274 f68f2ff91512c1 Kees Cook 2021-04-20 275 /* f68f2ff91512c1 Kees Cook 2021-04-20 276 * To make sure the compiler can enforce protection against buffer overflows, f68f2ff91512c1 Kees Cook 2021-04-20 277 * memcpy(), memmove(), and memset() must not be used beyond individual f68f2ff91512c1 Kees Cook 2021-04-20 278 * struct members. If you need to copy across multiple members, please use f68f2ff91512c1 Kees Cook 2021-04-20 279 * struct_group() to create a named mirror of an anonymous struct union. f68f2ff91512c1 Kees Cook 2021-04-20 280 * (e.g. see struct sk_buff.) Read overflow checking is currently only f68f2ff91512c1 Kees Cook 2021-04-20 281 * done when a write overflow is also present, or when building with W=1. f68f2ff91512c1 Kees Cook 2021-04-20 282 * f68f2ff91512c1 Kees Cook 2021-04-20 283 * Mitigation coverage matrix f68f2ff91512c1 Kees Cook 2021-04-20 284 * Bounds checking at: f68f2ff91512c1 Kees Cook 2021-04-20 285 * +-------+-------+-------+-------+ f68f2ff91512c1 Kees Cook 2021-04-20 286 * | Compile time | Run time | f68f2ff91512c1 Kees Cook 2021-04-20 287 * memcpy() argument sizes: | write | read | write | read | f68f2ff91512c1 Kees Cook 2021-04-20 288 * dest source length +-------+-------+-------+-------+ f68f2ff91512c1 Kees Cook 2021-04-20 289 * memcpy(known, known, constant) | y | y | n/a | n/a | f68f2ff91512c1 Kees Cook 2021-04-20 290 * memcpy(known, unknown, constant) | y | n | n/a | V | f68f2ff91512c1 Kees Cook 2021-04-20 291 * memcpy(known, known, dynamic) | n | n | B | B | f68f2ff91512c1 Kees Cook 2021-04-20 292 * memcpy(known, unknown, dynamic) | n | n | B | V | f68f2ff91512c1 Kees Cook 2021-04-20 293 * memcpy(unknown, known, constant) | n | y | V | n/a | f68f2ff91512c1 Kees Cook 2021-04-20 294 * memcpy(unknown, unknown, constant) | n | n | V | V | f68f2ff91512c1 Kees Cook 2021-04-20 295 * memcpy(unknown, known, dynamic) | n | n | V | B | f68f2ff91512c1 Kees Cook 2021-04-20 296 * memcpy(unknown, unknown, dynamic) | n | n | V | V | f68f2ff91512c1 Kees Cook 2021-04-20 297 * +-------+-------+-------+-------+ f68f2ff91512c1 Kees Cook 2021-04-20 298 * f68f2ff91512c1 Kees Cook 2021-04-20 299 * y = perform deterministic compile-time bounds checking f68f2ff91512c1 Kees Cook 2021-04-20 300 * n = cannot perform deterministic compile-time bounds checking f68f2ff91512c1 Kees Cook 2021-04-20 301 * n/a = no run-time bounds checking needed since compile-time deterministic f68f2ff91512c1 Kees Cook 2021-04-20 302 * B = can perform run-time bounds checking (currently unimplemented) f68f2ff91512c1 Kees Cook 2021-04-20 303 * V = vulnerable to run-time overflow (will need refactoring to solve) f68f2ff91512c1 Kees Cook 2021-04-20 304 * f68f2ff91512c1 Kees Cook 2021-04-20 305 */ f68f2ff91512c1 Kees Cook 2021-04-20 306 __FORTIFY_INLINE void fortify_memcpy_chk(__kernel_size_t size, f68f2ff91512c1 Kees Cook 2021-04-20 307 const size_t p_size, f68f2ff91512c1 Kees Cook 2021-04-20 308 const size_t q_size, f68f2ff91512c1 Kees Cook 2021-04-20 309 const size_t p_size_field, f68f2ff91512c1 Kees Cook 2021-04-20 310 const size_t q_size_field, f68f2ff91512c1 Kees Cook 2021-04-20 311 const char *func) a28a6e860c6cf2 Francis Laniel 2021-02-25 312 { a28a6e860c6cf2 Francis Laniel 2021-02-25 313 if (__builtin_constant_p(size)) { f68f2ff91512c1 Kees Cook 2021-04-20 314 /* f68f2ff91512c1 Kees Cook 2021-04-20 315 * Length argument is a constant expression, so we f68f2ff91512c1 Kees Cook 2021-04-20 316 * can perform compile-time bounds checking where f68f2ff91512c1 Kees Cook 2021-04-20 317 * buffer sizes are known. f68f2ff91512c1 Kees Cook 2021-04-20 318 */ f68f2ff91512c1 Kees Cook 2021-04-20 319 f68f2ff91512c1 Kees Cook 2021-04-20 320 /* Error when size is larger than enclosing struct. */ f68f2ff91512c1 Kees Cook 2021-04-20 321 if (p_size > p_size_field && p_size < size) a28a6e860c6cf2 Francis Laniel 2021-02-25 322 __write_overflow(); f68f2ff91512c1 Kees Cook 2021-04-20 323 if (q_size > q_size_field && q_size < size) a28a6e860c6cf2 Francis Laniel 2021-02-25 324 __read_overflow2(); f68f2ff91512c1 Kees Cook 2021-04-20 325 f68f2ff91512c1 Kees Cook 2021-04-20 326 /* Warn when write size argument larger than dest field. */ f68f2ff91512c1 Kees Cook 2021-04-20 327 if (p_size_field < size) f68f2ff91512c1 Kees Cook 2021-04-20 328 __write_overflow_field(p_size_field, size); f68f2ff91512c1 Kees Cook 2021-04-20 329 /* f68f2ff91512c1 Kees Cook 2021-04-20 330 * Warn for source field over-read when building with W=1 f68f2ff91512c1 Kees Cook 2021-04-20 331 * or when an over-write happened, so both can be fixed at f68f2ff91512c1 Kees Cook 2021-04-20 332 * the same time. f68f2ff91512c1 Kees Cook 2021-04-20 333 */ f68f2ff91512c1 Kees Cook 2021-04-20 334 if ((IS_ENABLED(KBUILD_EXTRA_WARN1) || p_size_field < size) && f68f2ff91512c1 Kees Cook 2021-04-20 335 q_size_field < size) f68f2ff91512c1 Kees Cook 2021-04-20 @336 __read_overflow2_field(q_size_field, size); a28a6e860c6cf2 Francis Laniel 2021-02-25 337 } f68f2ff91512c1 Kees Cook 2021-04-20 338 /* f68f2ff91512c1 Kees Cook 2021-04-20 339 * At this point, length argument may not be a constant expression, f68f2ff91512c1 Kees Cook 2021-04-20 340 * so run-time bounds checking can be done where buffer sizes are f68f2ff91512c1 Kees Cook 2021-04-20 341 * known. (This is not an "else" because the above checks may only f68f2ff91512c1 Kees Cook 2021-04-20 342 * be compile-time warnings, and we want to still warn for run-time f68f2ff91512c1 Kees Cook 2021-04-20 343 * overflows.) f68f2ff91512c1 Kees Cook 2021-04-20 344 */ f68f2ff91512c1 Kees Cook 2021-04-20 345 f68f2ff91512c1 Kees Cook 2021-04-20 346 /* f68f2ff91512c1 Kees Cook 2021-04-20 347 * Always stop accesses beyond the struct that contains the f68f2ff91512c1 Kees Cook 2021-04-20 348 * field, when the buffer's remaining size is known. f68f2ff91512c1 Kees Cook 2021-04-20 349 * (The -1 test is to optimize away checks where the buffer f68f2ff91512c1 Kees Cook 2021-04-20 350 * lengths are unknown.) f68f2ff91512c1 Kees Cook 2021-04-20 351 */ f68f2ff91512c1 Kees Cook 2021-04-20 352 if ((p_size != (size_t)(-1) && p_size < size) || f68f2ff91512c1 Kees Cook 2021-04-20 353 (q_size != (size_t)(-1) && q_size < size)) f68f2ff91512c1 Kees Cook 2021-04-20 354 fortify_panic(func); a28a6e860c6cf2 Francis Laniel 2021-02-25 355 } a28a6e860c6cf2 Francis Laniel 2021-02-25 356 :::::: The code at line 336 was first introduced by commit :::::: f68f2ff91512c199ec24883001245912afc17873 fortify: Detect struct member overflows in memcpy() at compile-time :::::: TO: Kees Cook <keescook@xxxxxxxxxxxx> :::::: CC: Kees Cook <keescook@xxxxxxxxxxxx> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
