tree: https://github.com/Paragon-Software-Group/linux-ntfs3.git master head: 7529036a025ad8bbd664f3aad8bd726e664a6db7 commit: 7495ce846bbe4f38d7ea5e023e44ad864b6348ad [2/16] fs/ntfs3: Use swap() to improve code config: x86_64-randconfig-161-20240824 (https://download.01.org/0day-ci/archive/20240824/202408242247.tSSqBPqy-lkp@xxxxxxxxx/config) compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> | Closes: https://lore.kernel.org/r/202408242247.tSSqBPqy-lkp@xxxxxxxxx/ smatch warnings: fs/ntfs3/lib/lzx_decompress.c:555 lzx_decompress_block() error: uninitialized symbol 'match_offset'. vim +/match_offset +555 fs/ntfs3/lib/lzx_decompress.c 522e010b58379f Konstantin Komarov 2021-08-13 471 static int lzx_decompress_block(const struct lzx_decompressor *d, 522e010b58379f Konstantin Komarov 2021-08-13 472 struct input_bitstream *is, 522e010b58379f Konstantin Komarov 2021-08-13 473 int block_type, u32 block_size, 522e010b58379f Konstantin Komarov 2021-08-13 474 u8 * const out_begin, u8 *out_next, 522e010b58379f Konstantin Komarov 2021-08-13 475 u32 recent_offsets[]) 522e010b58379f Konstantin Komarov 2021-08-13 476 { 522e010b58379f Konstantin Komarov 2021-08-13 477 u8 * const block_end = out_next + block_size; 522e010b58379f Konstantin Komarov 2021-08-13 478 u32 ones_if_aligned = 0U - (block_type == LZX_BLOCKTYPE_ALIGNED); 522e010b58379f Konstantin Komarov 2021-08-13 479 522e010b58379f Konstantin Komarov 2021-08-13 480 do { 522e010b58379f Konstantin Komarov 2021-08-13 481 u32 mainsym; 522e010b58379f Konstantin Komarov 2021-08-13 482 u32 match_len; 522e010b58379f Konstantin Komarov 2021-08-13 483 u32 match_offset; 522e010b58379f Konstantin Komarov 2021-08-13 484 u32 offset_slot; 522e010b58379f Konstantin Komarov 2021-08-13 485 u32 num_extra_bits; 522e010b58379f Konstantin Komarov 2021-08-13 486 522e010b58379f Konstantin Komarov 2021-08-13 487 mainsym = read_mainsym(d, is); 522e010b58379f Konstantin Komarov 2021-08-13 488 if (mainsym < LZX_NUM_CHARS) { 522e010b58379f Konstantin Komarov 2021-08-13 489 /* Literal */ 522e010b58379f Konstantin Komarov 2021-08-13 490 *out_next++ = mainsym; 522e010b58379f Konstantin Komarov 2021-08-13 491 continue; 522e010b58379f Konstantin Komarov 2021-08-13 492 } 522e010b58379f Konstantin Komarov 2021-08-13 493 522e010b58379f Konstantin Komarov 2021-08-13 494 /* Match */ 522e010b58379f Konstantin Komarov 2021-08-13 495 522e010b58379f Konstantin Komarov 2021-08-13 496 /* Decode the length header and offset slot. */ 522e010b58379f Konstantin Komarov 2021-08-13 497 mainsym -= LZX_NUM_CHARS; 522e010b58379f Konstantin Komarov 2021-08-13 498 match_len = mainsym % LZX_NUM_LEN_HEADERS; 522e010b58379f Konstantin Komarov 2021-08-13 499 offset_slot = mainsym / LZX_NUM_LEN_HEADERS; 522e010b58379f Konstantin Komarov 2021-08-13 500 522e010b58379f Konstantin Komarov 2021-08-13 501 /* If needed, read a length symbol to decode the full length. */ 522e010b58379f Konstantin Komarov 2021-08-13 502 if (match_len == LZX_NUM_PRIMARY_LENS) 522e010b58379f Konstantin Komarov 2021-08-13 503 match_len += read_lensym(d, is); 522e010b58379f Konstantin Komarov 2021-08-13 504 match_len += LZX_MIN_MATCH_LEN; 522e010b58379f Konstantin Komarov 2021-08-13 505 522e010b58379f Konstantin Komarov 2021-08-13 506 if (offset_slot < LZX_NUM_RECENT_OFFSETS) { 522e010b58379f Konstantin Komarov 2021-08-13 507 /* Repeat offset */ 522e010b58379f Konstantin Komarov 2021-08-13 508 522e010b58379f Konstantin Komarov 2021-08-13 509 /* Note: This isn't a real LRU queue, since using the R2 522e010b58379f Konstantin Komarov 2021-08-13 510 * offset doesn't bump the R1 offset down to R2. This 522e010b58379f Konstantin Komarov 2021-08-13 511 * quirk allows all 3 recent offsets to be handled by 522e010b58379f Konstantin Komarov 2021-08-13 512 * the same code. (For R0, the swap is a no-op.) 522e010b58379f Konstantin Komarov 2021-08-13 513 */ 7495ce846bbe4f Thorsten Blum 2024-07-31 514 swap(recent_offsets[offset_slot], recent_offsets[0]); match_offset not set on this path 522e010b58379f Konstantin Komarov 2021-08-13 515 } else { 522e010b58379f Konstantin Komarov 2021-08-13 516 /* Explicit offset */ 522e010b58379f Konstantin Komarov 2021-08-13 517 522e010b58379f Konstantin Komarov 2021-08-13 518 /* Look up the number of extra bits that need to be read 522e010b58379f Konstantin Komarov 2021-08-13 519 * to decode offsets with this offset slot. 522e010b58379f Konstantin Komarov 2021-08-13 520 */ 522e010b58379f Konstantin Komarov 2021-08-13 521 num_extra_bits = lzx_extra_offset_bits[offset_slot]; 522e010b58379f Konstantin Komarov 2021-08-13 522 522e010b58379f Konstantin Komarov 2021-08-13 523 /* Start with the offset slot base value. */ 522e010b58379f Konstantin Komarov 2021-08-13 524 match_offset = lzx_offset_slot_base[offset_slot]; 522e010b58379f Konstantin Komarov 2021-08-13 525 522e010b58379f Konstantin Komarov 2021-08-13 526 /* In aligned offset blocks, the low-order 3 bits of 522e010b58379f Konstantin Komarov 2021-08-13 527 * each offset are encoded using the aligned offset 522e010b58379f Konstantin Komarov 2021-08-13 528 * code. Otherwise, all the extra bits are literal. 522e010b58379f Konstantin Komarov 2021-08-13 529 */ 522e010b58379f Konstantin Komarov 2021-08-13 530 522e010b58379f Konstantin Komarov 2021-08-13 531 if ((num_extra_bits & ones_if_aligned) >= LZX_NUM_ALIGNED_OFFSET_BITS) { 522e010b58379f Konstantin Komarov 2021-08-13 532 match_offset += 522e010b58379f Konstantin Komarov 2021-08-13 533 bitstream_read_bits(is, num_extra_bits - 522e010b58379f Konstantin Komarov 2021-08-13 534 LZX_NUM_ALIGNED_OFFSET_BITS) 522e010b58379f Konstantin Komarov 2021-08-13 535 << LZX_NUM_ALIGNED_OFFSET_BITS; 522e010b58379f Konstantin Komarov 2021-08-13 536 match_offset += read_alignedsym(d, is); 522e010b58379f Konstantin Komarov 2021-08-13 537 } else { 522e010b58379f Konstantin Komarov 2021-08-13 538 match_offset += bitstream_read_bits(is, num_extra_bits); 522e010b58379f Konstantin Komarov 2021-08-13 539 } 522e010b58379f Konstantin Komarov 2021-08-13 540 522e010b58379f Konstantin Komarov 2021-08-13 541 /* Adjust the offset. */ 522e010b58379f Konstantin Komarov 2021-08-13 542 match_offset -= (LZX_NUM_RECENT_OFFSETS - 1); 522e010b58379f Konstantin Komarov 2021-08-13 543 522e010b58379f Konstantin Komarov 2021-08-13 544 /* Update the recent offsets. */ 522e010b58379f Konstantin Komarov 2021-08-13 545 recent_offsets[2] = recent_offsets[1]; 522e010b58379f Konstantin Komarov 2021-08-13 546 recent_offsets[1] = recent_offsets[0]; 522e010b58379f Konstantin Komarov 2021-08-13 547 recent_offsets[0] = match_offset; 522e010b58379f Konstantin Komarov 2021-08-13 548 } 522e010b58379f Konstantin Komarov 2021-08-13 549 522e010b58379f Konstantin Komarov 2021-08-13 550 /* Validate the match, then copy it to the current position. */ 522e010b58379f Konstantin Komarov 2021-08-13 551 522e010b58379f Konstantin Komarov 2021-08-13 552 if (match_len > (size_t)(block_end - out_next)) 522e010b58379f Konstantin Komarov 2021-08-13 553 return -1; 522e010b58379f Konstantin Komarov 2021-08-13 554 522e010b58379f Konstantin Komarov 2021-08-13 @555 if (match_offset > (size_t)(out_next - out_begin)) ^^^^^^^^^^^^ Uninitialized. 522e010b58379f Konstantin Komarov 2021-08-13 556 return -1; 522e010b58379f Konstantin Komarov 2021-08-13 557 522e010b58379f Konstantin Komarov 2021-08-13 558 out_next = lz_copy(out_next, match_len, match_offset, 522e010b58379f Konstantin Komarov 2021-08-13 559 block_end, LZX_MIN_MATCH_LEN); 522e010b58379f Konstantin Komarov 2021-08-13 560 522e010b58379f Konstantin Komarov 2021-08-13 561 } while (out_next != block_end); 522e010b58379f Konstantin Komarov 2021-08-13 562 522e010b58379f Konstantin Komarov 2021-08-13 563 return 0; 522e010b58379f Konstantin Komarov 2021-08-13 564 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
