:::::: :::::: Manual check reason: "low confidence bisect report" :::::: Manual check reason: "low confidence static check first_new_problem: fs/ntfs3/lznt.c:234:16: warning: use of uninitialized value '<unknown>' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]" ::::::
BCC: [email protected] CC: [email protected] CC: [email protected] TO: Konstantin Komarov <[email protected]> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: c1c76700a0d6e6090ccfe1209527f14c21b6681b commit: 6e5be40d32fb1907285277c02e74493ed43d77fe fs/ntfs3: Add NTFS3 in fs/Kconfig and fs/Makefile date: 12 months ago :::::: branch date: 4 hours ago :::::: commit date: 12 months ago config: arm-randconfig-c002-20220801 (https://download.01.org/0day-ci/archive/20220805/[email protected]/config) compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0 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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6e5be40d32fb1907285277c02e74493ed43d77fe git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 6e5be40d32fb1907285277c02e74493ed43d77fe # save the config file COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross ARCH=arm KBUILD_USERCFLAGS='-fanalyzer -Wno-error' If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <[email protected]> gcc-analyzer warnings: (new ones prefixed by >>) fs/ntfs3/lznt.c: In function 'decompress_chunk': >> fs/ntfs3/lznt.c:234:16: warning: use of uninitialized value '<unknown>' >> [CWE-457] [-Wanalyzer-use-of-uninitialized-value] 234 | size_t offset, length; | ^~~~~~ 'decompress_chunk': event 1 | | 234 | size_t offset, length; | | ^~~~~~ | | | | | (1) use of uninitialized value '<unknown>' here | vim +234 fs/ntfs3/lznt.c 522e010b58379f Konstantin Komarov 2021-08-13 225 522e010b58379f Konstantin Komarov 2021-08-13 226 static inline ssize_t decompress_chunk(u8 *unc, u8 *unc_end, const u8 *cmpr, 522e010b58379f Konstantin Komarov 2021-08-13 227 const u8 *cmpr_end) 522e010b58379f Konstantin Komarov 2021-08-13 228 { 522e010b58379f Konstantin Komarov 2021-08-13 229 u8 *up = unc; 522e010b58379f Konstantin Komarov 2021-08-13 230 u8 ch = *cmpr++; 522e010b58379f Konstantin Komarov 2021-08-13 231 size_t bit = 0; 522e010b58379f Konstantin Komarov 2021-08-13 232 size_t index = 0; 522e010b58379f Konstantin Komarov 2021-08-13 233 u16 pair; 522e010b58379f Konstantin Komarov 2021-08-13 @234 size_t offset, length; 522e010b58379f Konstantin Komarov 2021-08-13 235 522e010b58379f Konstantin Komarov 2021-08-13 236 /* Do decompression until pointers are inside range */ 522e010b58379f Konstantin Komarov 2021-08-13 237 while (up < unc_end && cmpr < cmpr_end) { 522e010b58379f Konstantin Komarov 2021-08-13 238 /* Correct index */ 522e010b58379f Konstantin Komarov 2021-08-13 239 while (unc + s_max_off[index] < up) 522e010b58379f Konstantin Komarov 2021-08-13 240 index += 1; 522e010b58379f Konstantin Komarov 2021-08-13 241 522e010b58379f Konstantin Komarov 2021-08-13 242 /* Check the current flag for zero */ 522e010b58379f Konstantin Komarov 2021-08-13 243 if (!(ch & (1 << bit))) { 522e010b58379f Konstantin Komarov 2021-08-13 244 /* Just copy byte */ 522e010b58379f Konstantin Komarov 2021-08-13 245 *up++ = *cmpr++; 522e010b58379f Konstantin Komarov 2021-08-13 246 goto next; 522e010b58379f Konstantin Komarov 2021-08-13 247 } 522e010b58379f Konstantin Komarov 2021-08-13 248 522e010b58379f Konstantin Komarov 2021-08-13 249 /* Check for boundary */ 522e010b58379f Konstantin Komarov 2021-08-13 250 if (cmpr + 1 >= cmpr_end) 522e010b58379f Konstantin Komarov 2021-08-13 251 return -EINVAL; 522e010b58379f Konstantin Komarov 2021-08-13 252 522e010b58379f Konstantin Komarov 2021-08-13 253 /* Read a short from little endian stream */ 522e010b58379f Konstantin Komarov 2021-08-13 254 pair = cmpr[1]; 522e010b58379f Konstantin Komarov 2021-08-13 255 pair <<= 8; 522e010b58379f Konstantin Komarov 2021-08-13 256 pair |= cmpr[0]; 522e010b58379f Konstantin Komarov 2021-08-13 257 522e010b58379f Konstantin Komarov 2021-08-13 258 cmpr += 2; 522e010b58379f Konstantin Komarov 2021-08-13 259 522e010b58379f Konstantin Komarov 2021-08-13 260 /* Translate packed information into offset and length */ 522e010b58379f Konstantin Komarov 2021-08-13 261 length = parse_pair(pair, &offset, index); 522e010b58379f Konstantin Komarov 2021-08-13 262 522e010b58379f Konstantin Komarov 2021-08-13 263 /* Check offset for boundary */ 522e010b58379f Konstantin Komarov 2021-08-13 264 if (unc + offset > up) 522e010b58379f Konstantin Komarov 2021-08-13 265 return -EINVAL; 522e010b58379f Konstantin Komarov 2021-08-13 266 522e010b58379f Konstantin Komarov 2021-08-13 267 /* Truncate the length if necessary */ 522e010b58379f Konstantin Komarov 2021-08-13 268 if (up + length >= unc_end) 522e010b58379f Konstantin Komarov 2021-08-13 269 length = unc_end - up; 522e010b58379f Konstantin Komarov 2021-08-13 270 522e010b58379f Konstantin Komarov 2021-08-13 271 /* Now we copy bytes. This is the heart of LZ algorithm. */ 522e010b58379f Konstantin Komarov 2021-08-13 272 for (; length > 0; length--, up++) 522e010b58379f Konstantin Komarov 2021-08-13 273 *up = *(up - offset); 522e010b58379f Konstantin Komarov 2021-08-13 274 522e010b58379f Konstantin Komarov 2021-08-13 275 next: 522e010b58379f Konstantin Komarov 2021-08-13 276 /* Advance flag bit value */ 522e010b58379f Konstantin Komarov 2021-08-13 277 bit = (bit + 1) & 7; 522e010b58379f Konstantin Komarov 2021-08-13 278 522e010b58379f Konstantin Komarov 2021-08-13 279 if (!bit) { 522e010b58379f Konstantin Komarov 2021-08-13 280 if (cmpr >= cmpr_end) 522e010b58379f Konstantin Komarov 2021-08-13 281 break; 522e010b58379f Konstantin Komarov 2021-08-13 282 522e010b58379f Konstantin Komarov 2021-08-13 283 ch = *cmpr++; 522e010b58379f Konstantin Komarov 2021-08-13 284 } 522e010b58379f Konstantin Komarov 2021-08-13 285 } 522e010b58379f Konstantin Komarov 2021-08-13 286 522e010b58379f Konstantin Komarov 2021-08-13 287 /* return the size of uncompressed data */ 522e010b58379f Konstantin Komarov 2021-08-13 288 return up - unc; 522e010b58379f Konstantin Komarov 2021-08-13 289 } 522e010b58379f Konstantin Komarov 2021-08-13 290 :::::: The code at line 234 was first introduced by commit :::::: 522e010b58379fbe19b38fdef5016bca0c3cf405 fs/ntfs3: Add compression :::::: TO: Konstantin Komarov <[email protected]> :::::: CC: Konstantin Komarov <[email protected]> -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
