diff options
Diffstat (limited to 'third_party/libpng16/pngrutil.c')
| -rw-r--r-- | third_party/libpng16/pngrutil.c | 538 |
1 files changed, 335 insertions, 203 deletions
diff --git a/third_party/libpng16/pngrutil.c b/third_party/libpng16/pngrutil.c index c9747fc27d..2210ffc75b 100644 --- a/third_party/libpng16/pngrutil.c +++ b/third_party/libpng16/pngrutil.c @@ -1,8 +1,8 @@ /* pngrutil.c - utilities to read a PNG file * - * Last changed in libpng 1.6.20 [December 3, 2014] - * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson + * Last changed in libpng 1.6.33 [September 28, 2017] + * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) * @@ -86,11 +86,11 @@ png_get_int_32)(png_const_bytep buf) { png_uint_32 uval = png_get_uint_32(buf); if ((uval & 0x80000000) == 0) /* non-negative */ - return uval; + return (png_int_32)uval; uval = (uval ^ 0xffffffff) + 1; /* 2's complement: -x = ~x+1 */ if ((uval & 0x80000000) == 0) /* no overflow */ - return -(png_int_32)uval; + return -(png_int_32)uval; /* The following has to be safe; this function only gets called on PNG data * and if we get here that data is invalid. 0 is the most safe value and * if not then an attacker would surely just generate a PNG with 0 instead. @@ -181,6 +181,9 @@ png_read_chunk_header(png_structrp png_ptr) /* Check to see if chunk name is valid. */ png_check_chunk_name(png_ptr, png_ptr->chunk_name); + /* Check for too-large chunk length */ + png_check_chunk_length(png_ptr, length); + #ifdef PNG_IO_STATE_SUPPORTED png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_DATA; #endif @@ -311,6 +314,7 @@ png_read_buffer(png_structrp png_ptr, png_alloc_size_t new_size, int warn) if (buffer != NULL) { + memset(buffer, 0, new_size); /* just in case */ png_ptr->read_buffer = buffer; png_ptr->read_buffer_size = new_size; } @@ -370,11 +374,10 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner) */ { int ret; /* zlib return code */ -#if PNG_ZLIB_VERNUM >= 0x1240 +#if ZLIB_VERNUM >= 0x1240 + int window_bits = 0; # if defined(PNG_SET_OPTION_SUPPORTED) && defined(PNG_MAXIMUM_INFLATE_WINDOW) - int window_bits; - if (((png_ptr->options >> PNG_MAXIMUM_INFLATE_WINDOW) & 3) == PNG_OPTION_ON) { @@ -384,13 +387,11 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner) else { - window_bits = 0; png_ptr->zstream_start = 1; } -# else -# define window_bits 0 # endif -#endif + +#endif /* ZLIB_VERNUM >= 0x1240 */ /* Set this for safety, just in case the previous owner left pointers to * memory allocations. @@ -402,25 +403,32 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner) if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0) { -#if PNG_ZLIB_VERNUM < 0x1240 - ret = inflateReset(&png_ptr->zstream); -#else +#if ZLIB_VERNUM >= 0x1240 ret = inflateReset2(&png_ptr->zstream, window_bits); +#else + ret = inflateReset(&png_ptr->zstream); #endif } else { -#if PNG_ZLIB_VERNUM < 0x1240 - ret = inflateInit(&png_ptr->zstream); -#else +#if ZLIB_VERNUM >= 0x1240 ret = inflateInit2(&png_ptr->zstream, window_bits); +#else + ret = inflateInit(&png_ptr->zstream); #endif if (ret == Z_OK) png_ptr->flags |= PNG_FLAG_ZSTREAM_INITIALIZED; } +#if ZLIB_VERNUM >= 0x1290 && \ + defined(PNG_SET_OPTION_SUPPORTED) && defined(PNG_IGNORE_ADLER32) + if (((png_ptr->options >> PNG_IGNORE_ADLER32) & 3) == PNG_OPTION_ON) + /* Turn off validation of the ADLER32 checksum in IDAT chunks */ + ret = inflateValidate(&png_ptr->zstream, 0); +#endif + if (ret == Z_OK) png_ptr->zowner = owner; @@ -435,7 +443,7 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner) #endif } -#if PNG_ZLIB_VERNUM >= 0x1240 +#if ZLIB_VERNUM >= 0x1240 /* Handle the start of the inflate stream if we called inflateInit2(strm,0); * in this case some zlib versions skip validation of the CINFO field and, in * certain circumstances, libpng may end up displaying an invalid image, in @@ -461,6 +469,7 @@ png_zlib_inflate(png_structrp png_ptr, int flush) #endif /* Zlib >= 1.2.4 */ #ifdef PNG_READ_COMPRESSED_TEXT_SUPPORTED +#if defined(PNG_READ_zTXt_SUPPORTED) || defined (PNG_READ_iTXt_SUPPORTED) /* png_inflate now returns zlib error codes including Z_OK and Z_STREAM_END to * allow the caller to do multiple calls if required. If the 'finish' flag is * set Z_FINISH will be passed to the final inflate() call and Z_STREAM_END must @@ -599,9 +608,9 @@ png_inflate(png_structrp png_ptr, png_uint_32 owner, int finish, */ static int png_decompress_chunk(png_structrp png_ptr, - png_uint_32 chunklength, png_uint_32 prefix_size, - png_alloc_size_t *newlength /* must be initialized to the maximum! */, - int terminate /*add a '\0' to the end of the uncompressed data*/) + png_uint_32 chunklength, png_uint_32 prefix_size, + png_alloc_size_t *newlength /* must be initialized to the maximum! */, + int terminate /*add a '\0' to the end of the uncompressed data*/) { /* TODO: implement different limits for different types of chunk. * @@ -638,8 +647,8 @@ png_decompress_chunk(png_structrp png_ptr, png_uint_32 lzsize = chunklength - prefix_size; ret = png_inflate(png_ptr, png_ptr->chunk_name, 1/*finish*/, - /* input: */ png_ptr->read_buffer + prefix_size, &lzsize, - /* output: */ NULL, newlength); + /* input: */ png_ptr->read_buffer + prefix_size, &lzsize, + /* output: */ NULL, newlength); if (ret == Z_STREAM_END) { @@ -659,15 +668,17 @@ png_decompress_chunk(png_structrp png_ptr, */ png_alloc_size_t new_size = *newlength; png_alloc_size_t buffer_size = prefix_size + new_size + - (terminate != 0); + (terminate != 0); png_bytep text = png_voidcast(png_bytep, png_malloc_base(png_ptr, - buffer_size)); + buffer_size)); if (text != NULL) { + memset(text, 0, buffer_size); + ret = png_inflate(png_ptr, png_ptr->chunk_name, 1/*finish*/, - png_ptr->read_buffer + prefix_size, &lzsize, - text + prefix_size, newlength); + png_ptr->read_buffer + prefix_size, &lzsize, + text + prefix_size, newlength); if (ret == Z_STREAM_END) { @@ -712,7 +723,7 @@ png_decompress_chunk(png_structrp png_ptr, * the extra space may otherwise be used as a Trojan Horse. */ if (ret == Z_STREAM_END && - chunklength - prefix_size != lzsize) + chunklength - prefix_size != lzsize) png_chunk_benign_error(png_ptr, "extra compressed data"); } @@ -728,9 +739,7 @@ png_decompress_chunk(png_structrp png_ptr, { /* inflateReset failed, store the error message */ png_zstream_error(png_ptr, ret); - - if (ret == Z_STREAM_END) - ret = PNG_UNEXPECTED_ZLIB_RETURN; + ret = PNG_UNEXPECTED_ZLIB_RETURN; } } @@ -754,6 +763,7 @@ png_decompress_chunk(png_structrp png_ptr, return Z_MEM_ERROR; } } +#endif /* READ_zTXt || READ_iTXt */ #endif /* READ_COMPRESSED_TEXT */ #ifdef PNG_READ_iCCP_SUPPORTED @@ -762,8 +772,8 @@ png_decompress_chunk(png_structrp png_ptr, */ static int png_inflate_read(png_structrp png_ptr, png_bytep read_buffer, uInt read_size, - png_uint_32p chunk_bytes, png_bytep next_out, png_alloc_size_t *out_size, - int finish) + png_uint_32p chunk_bytes, png_bytep next_out, png_alloc_size_t *out_size, + int finish) { if (png_ptr->zowner == png_ptr->chunk_name) { @@ -802,8 +812,8 @@ png_inflate_read(png_structrp png_ptr, png_bytep read_buffer, uInt read_size, * the available output is produced; this allows reading of truncated * streams. */ - ret = PNG_INFLATE(png_ptr, - *chunk_bytes > 0 ? Z_NO_FLUSH : (finish ? Z_FINISH : Z_SYNC_FLUSH)); + ret = PNG_INFLATE(png_ptr, *chunk_bytes > 0 ? + Z_NO_FLUSH : (finish ? Z_FINISH : Z_SYNC_FLUSH)); } while (ret == Z_OK && (*out_size > 0 || png_ptr->zstream.avail_out > 0)); @@ -821,7 +831,7 @@ png_inflate_read(png_structrp png_ptr, png_bytep read_buffer, uInt read_size, return Z_STREAM_ERROR; } } -#endif +#endif /* READ_iCCP */ /* Read and check the IDHR chunk */ @@ -1009,7 +1019,7 @@ png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) #endif { - png_crc_finish(png_ptr, (int) length - num * 3); + png_crc_finish(png_ptr, (png_uint_32) (length - (unsigned int)num * 3)); } #ifndef PNG_READ_OPT_PLTE_SUPPORTED @@ -1292,7 +1302,7 @@ png_handle_cHRM(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) png_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM; (void)png_colorspace_set_chromaticities(png_ptr, &png_ptr->colorspace, &xy, - 1/*prefer cHRM values*/); + 1/*prefer cHRM values*/); png_colorspace_sync(png_ptr, info_ptr); } #endif @@ -1371,11 +1381,13 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) * chunk is just ignored, so does not invalidate the color space. An * alternative is to set the 'invalid' flags at the start of this routine * and only clear them in they were not set before and all the tests pass. - * The minimum 'deflate' stream is assumed to be just the 2 byte header and - * 4 byte checksum. The keyword must be at least one character and there is - * a terminator (0) byte and the compression method. */ - if (length < 9) + + /* The keyword must be at least one character and there is a + * terminator (0) byte and the compression method byte, and the + * 'zlib' datastream is at least 11 bytes. + */ + if (length < 14) { png_crc_finish(png_ptr, length); png_chunk_benign_error(png_ptr, "too short"); @@ -1407,6 +1419,16 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) png_crc_read(png_ptr, (png_bytep)keyword, read_length); length -= read_length; + /* The minimum 'zlib' stream is assumed to be just the 2 byte header, + * 5 bytes minimum 'deflate' stream, and the 4 byte checksum. + */ + if (length < 11) + { + png_crc_finish(png_ptr, length); + png_chunk_benign_error(png_ptr, "too short"); + return; + } + keyword_length = 0; while (keyword_length < 80 && keyword_length < read_length && keyword[keyword_length] != 0) @@ -1425,15 +1447,15 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) if (png_inflate_claim(png_ptr, png_iCCP) == Z_OK) { - Byte profile_header[132]; + Byte profile_header[132]={0}; Byte local_buffer[PNG_INFLATE_BUF_SIZE]; png_alloc_size_t size = (sizeof profile_header); png_ptr->zstream.next_in = (Bytef*)keyword + (keyword_length+2); png_ptr->zstream.avail_in = read_length; (void)png_inflate_read(png_ptr, local_buffer, - (sizeof local_buffer), &length, profile_header, &size, - 0/*finish: don't, because the output is too small*/); + (sizeof local_buffer), &length, profile_header, &size, + 0/*finish: don't, because the output is too small*/); if (size == 0) { @@ -1443,35 +1465,35 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) png_get_uint_32(profile_header); if (png_icc_check_length(png_ptr, &png_ptr->colorspace, - keyword, profile_length) != 0) + keyword, profile_length) != 0) { /* The length is apparently ok, so we can check the 132 * byte header. */ if (png_icc_check_header(png_ptr, &png_ptr->colorspace, - keyword, profile_length, profile_header, - png_ptr->color_type) != 0) + keyword, profile_length, profile_header, + png_ptr->color_type) != 0) { /* Now read the tag table; a variable size buffer is * needed at this point, allocate one for the whole * profile. The header check has already validated - * that none of these stuff will overflow. + * that none of this stuff will overflow. */ const png_uint_32 tag_count = png_get_uint_32( - profile_header+128); + profile_header+128); png_bytep profile = png_read_buffer(png_ptr, - profile_length, 2/*silent*/); + profile_length, 2/*silent*/); if (profile != NULL) { memcpy(profile, profile_header, - (sizeof profile_header)); + (sizeof profile_header)); size = 12 * tag_count; (void)png_inflate_read(png_ptr, local_buffer, - (sizeof local_buffer), &length, - profile + (sizeof profile_header), &size, 0); + (sizeof local_buffer), &length, + profile + (sizeof profile_header), &size, 0); /* Still expect a buffer error because we expect * there to be some tag data! @@ -1479,22 +1501,22 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) if (size == 0) { if (png_icc_check_tag_table(png_ptr, - &png_ptr->colorspace, keyword, profile_length, - profile) != 0) + &png_ptr->colorspace, keyword, profile_length, + profile) != 0) { /* The profile has been validated for basic * security issues, so read the whole thing in. */ size = profile_length - (sizeof profile_header) - - 12 * tag_count; + - 12 * tag_count; (void)png_inflate_read(png_ptr, local_buffer, - (sizeof local_buffer), &length, - profile + (sizeof profile_header) + - 12 * tag_count, &size, 1/*finish*/); + (sizeof local_buffer), &length, + profile + (sizeof profile_header) + + 12 * tag_count, &size, 1/*finish*/); if (length > 0 && !(png_ptr->flags & - PNG_FLAG_BENIGN_ERRORS_WARN)) + PNG_FLAG_BENIGN_ERRORS_WARN)) errmsg = "extra compressed data"; /* But otherwise allow extra data: */ @@ -1506,34 +1528,34 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) * keep going. */ png_chunk_warning(png_ptr, - "extra compressed data"); + "extra compressed data"); } png_crc_finish(png_ptr, length); finished = 1; -# ifdef PNG_sRGB_SUPPORTED +# if defined(PNG_sRGB_SUPPORTED) && PNG_sRGB_PROFILE_CHECKS >= 0 /* Check for a match against sRGB */ png_icc_set_sRGB(png_ptr, - &png_ptr->colorspace, profile, - png_ptr->zstream.adler); -# endif + &png_ptr->colorspace, profile, + png_ptr->zstream.adler); +# endif /* Steal the profile for info_ptr. */ if (info_ptr != NULL) { png_free_data(png_ptr, info_ptr, - PNG_FREE_ICCP, 0); + PNG_FREE_ICCP, 0); info_ptr->iccp_name = png_voidcast(char*, - png_malloc_base(png_ptr, - keyword_length+1)); + png_malloc_base(png_ptr, + keyword_length+1)); if (info_ptr->iccp_name != NULL) { memcpy(info_ptr->iccp_name, keyword, - keyword_length+1); + keyword_length+1); info_ptr->iccp_proflen = - profile_length; + profile_length; info_ptr->iccp_profile = profile; png_ptr->read_buffer = NULL; /*steal*/ info_ptr->free_me |= PNG_FREE_ICCP; @@ -1562,19 +1584,11 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) return; } } - - else if (size > 0) - errmsg = "truncated"; - -#ifndef __COVERITY__ - else + if (errmsg == NULL) errmsg = png_ptr->zstream.msg; -#endif } - /* else png_icc_check_tag_table output an error */ } - else /* profile truncated */ errmsg = png_ptr->zstream.msg; } @@ -1715,13 +1729,13 @@ png_handle_sPLT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) data_length = length - (png_uint_32)(entry_start - buffer); /* Integrity-check the data length */ - if ((data_length % entry_size) != 0) + if ((data_length % (unsigned int)entry_size) != 0) { png_warning(png_ptr, "sPLT chunk has bad length"); return; } - dl = (png_int_32)(data_length / entry_size); + dl = (png_uint_32)(data_length / (unsigned int)entry_size); max_dl = PNG_SIZE_MAX / (sizeof (png_sPLT_entry)); if (dl > max_dl) @@ -1730,10 +1744,10 @@ png_handle_sPLT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) return; } - new_palette.nentries = (png_int_32)(data_length / entry_size); + new_palette.nentries = (png_int_32)(data_length / (unsigned int)entry_size); - new_palette.entries = (png_sPLT_entryp)png_malloc_warn( - png_ptr, new_palette.nentries * (sizeof (png_sPLT_entry))); + new_palette.entries = (png_sPLT_entryp)png_malloc_warn(png_ptr, + (png_alloc_size_t) new_palette.nentries * (sizeof (png_sPLT_entry))); if (new_palette.entries == NULL) { @@ -2003,6 +2017,69 @@ png_handle_bKGD(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) } #endif +#ifdef PNG_READ_eXIf_SUPPORTED +void /* PRIVATE */ +png_handle_eXIf(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) +{ + unsigned int i; + + png_debug(1, "in png_handle_eXIf"); + + if ((png_ptr->mode & PNG_HAVE_IHDR) == 0) + png_chunk_error(png_ptr, "missing IHDR"); + + if (length < 2) + { + png_crc_finish(png_ptr, length); + png_chunk_benign_error(png_ptr, "too short"); + return; + } + + else if (info_ptr == NULL || (info_ptr->valid & PNG_INFO_eXIf) != 0) + { + png_crc_finish(png_ptr, length); + png_chunk_benign_error(png_ptr, "duplicate"); + return; + } + + info_ptr->free_me |= PNG_FREE_EXIF; + + info_ptr->eXIf_buf = png_voidcast(png_bytep, + png_malloc_warn(png_ptr, length)); + + if (info_ptr->eXIf_buf == NULL) + { + png_crc_finish(png_ptr, length); + png_chunk_benign_error(png_ptr, "out of memory"); + return; + } + + for (i = 0; i < length; i++) + { + png_byte buf[1]; + png_crc_read(png_ptr, buf, 1); + info_ptr->eXIf_buf[i] = buf[0]; + if (i == 1 && buf[0] != 'M' && buf[0] != 'I' + && info_ptr->eXIf_buf[0] != buf[0]) + { + png_crc_finish(png_ptr, length); + png_chunk_benign_error(png_ptr, "incorrect byte-order specifier"); + png_free(png_ptr, info_ptr->eXIf_buf); + info_ptr->eXIf_buf = NULL; + return; + } + } + + if (png_crc_finish(png_ptr, 0) != 0) + return; + + png_set_eXIf_1(png_ptr, info_ptr, length, info_ptr->eXIf_buf); + + png_free(png_ptr, info_ptr->eXIf_buf); + info_ptr->eXIf_buf = NULL; +} +#endif + #ifdef PNG_READ_hIST_SUPPORTED void /* PRIVATE */ png_handle_hIST(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) @@ -2270,7 +2347,7 @@ png_handle_pCAL(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) } png_set_pCAL(png_ptr, info_ptr, (png_charp)buffer, X0, X1, type, nparams, - (png_charp)units, params); + (png_charp)units, params); png_free(png_ptr, params); } @@ -2313,7 +2390,7 @@ png_handle_sCAL(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) } png_debug1(2, "Allocating and reading sCAL chunk data (%u bytes)", - length + 1); + length + 1); buffer = png_read_buffer(png_ptr, length+1, 2/*silent*/); @@ -2365,7 +2442,7 @@ png_handle_sCAL(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) else /* This is the (only) success case. */ png_set_sCAL_s(png_ptr, info_ptr, buffer[0], - (png_charp)buffer+1, (png_charp)buffer+heighti); + (png_charp)buffer+1, (png_charp)buffer+heighti); } } #endif @@ -2465,8 +2542,8 @@ png_handle_tEXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) if (buffer == NULL) { - png_chunk_benign_error(png_ptr, "out of memory"); - return; + png_chunk_benign_error(png_ptr, "out of memory"); + return; } png_crc_read(png_ptr, buffer, length); @@ -2531,6 +2608,9 @@ png_handle_zTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) if ((png_ptr->mode & PNG_HAVE_IDAT) != 0) png_ptr->mode |= PNG_AFTER_IDAT; + /* Note, "length" is sufficient here; we won't be adding + * a null terminator later. + */ buffer = png_read_buffer(png_ptr, length, 2/*silent*/); if (buffer == NULL) @@ -2573,27 +2653,32 @@ png_handle_zTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) * and text chunks. */ if (png_decompress_chunk(png_ptr, length, keyword_length+2, - &uncompressed_length, 1/*terminate*/) == Z_STREAM_END) + &uncompressed_length, 1/*terminate*/) == Z_STREAM_END) { png_text text; - /* It worked; png_ptr->read_buffer now looks like a tEXt chunk except - * for the extra compression type byte and the fact that it isn't - * necessarily '\0' terminated. - */ - buffer = png_ptr->read_buffer; - buffer[uncompressed_length+(keyword_length+2)] = 0; - - text.compression = PNG_TEXT_COMPRESSION_zTXt; - text.key = (png_charp)buffer; - text.text = (png_charp)(buffer + keyword_length+2); - text.text_length = uncompressed_length; - text.itxt_length = 0; - text.lang = NULL; - text.lang_key = NULL; - - if (png_set_text_2(png_ptr, info_ptr, &text, 1) != 0) - errmsg = "insufficient memory"; + if (png_ptr->read_buffer == NULL) + errmsg="Read failure in png_handle_zTXt"; + else + { + /* It worked; png_ptr->read_buffer now looks like a tEXt chunk + * except for the extra compression type byte and the fact that + * it isn't necessarily '\0' terminated. + */ + buffer = png_ptr->read_buffer; + buffer[uncompressed_length+(keyword_length+2)] = 0; + + text.compression = PNG_TEXT_COMPRESSION_zTXt; + text.key = (png_charp)buffer; + text.text = (png_charp)(buffer + keyword_length+2); + text.text_length = uncompressed_length; + text.itxt_length = 0; + text.lang = NULL; + text.lang_key = NULL; + + if (png_set_text_2(png_ptr, info_ptr, &text, 1) != 0) + errmsg = "insufficient memory"; + } } else @@ -2713,7 +2798,7 @@ png_handle_iTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) * iCCP and text chunks. */ if (png_decompress_chunk(png_ptr, length, prefix_length, - &uncompressed_length, 1/*terminate*/) == Z_STREAM_END) + &uncompressed_length, 1/*terminate*/) == Z_STREAM_END) buffer = png_ptr->read_buffer; else @@ -2793,7 +2878,7 @@ png_cache_unknown_chunk(png_structrp png_ptr, png_uint_32 length) { /* Do a 'warn' here - it is handled below. */ png_ptr->unknown_chunk.data = png_voidcast(png_bytep, - png_malloc_warn(png_ptr, length)); + png_malloc_warn(png_ptr, length)); } } @@ -2818,7 +2903,7 @@ png_cache_unknown_chunk(png_structrp png_ptr, png_uint_32 length) /* Handle an unknown, or known but disabled, chunk */ void /* PRIVATE */ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, - png_uint_32 length, int keep) + png_uint_32 length, int keep) { int handled = 0; /* the chunk was handled */ @@ -2856,7 +2941,7 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, { /* Callback to user unknown chunk handler */ int ret = (*(png_ptr->read_user_chunk_fn))(png_ptr, - &png_ptr->unknown_chunk); + &png_ptr->unknown_chunk); /* ret is: * negative: An error occurred; png_chunk_error will be called. @@ -2890,9 +2975,9 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, { png_chunk_warning(png_ptr, "Saving unknown chunk:"); png_app_warning(png_ptr, - "forcing save of an unhandled chunk;" - " please call png_set_keep_unknown_chunks"); - /* with keep = PNG_HANDLE_CHUNK_IF_SAFE */ + "forcing save of an unhandled chunk;" + " please call png_set_keep_unknown_chunks"); + /* with keep = PNG_HANDLE_CHUNK_IF_SAFE */ } # endif keep = PNG_HANDLE_CHUNK_IF_SAFE; @@ -2969,7 +3054,7 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, case 2: png_ptr->user_chunk_cache_max = 1; png_chunk_benign_error(png_ptr, "no space in chunk cache"); - /* FALL THROUGH */ + /* FALLTHROUGH */ case 1: /* NOTE: prior to 1.6.0 this case resulted in an unknown critical * chunk being skipped, now there will be a hard error below. @@ -2978,14 +3063,14 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, default: /* not at limit */ --(png_ptr->user_chunk_cache_max); - /* FALL THROUGH */ + /* FALLTHROUGH */ case 0: /* no limit */ # endif /* USER_LIMITS */ /* Here when the limit isn't reached or when limits are compiled * out; store the chunk. */ png_set_unknown_chunks(png_ptr, info_ptr, - &png_ptr->unknown_chunk, 1); + &png_ptr->unknown_chunk, 1); handled = 1; # ifdef PNG_USER_LIMITS_SUPPORTED break; @@ -3029,20 +3114,58 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, */ void /* PRIVATE */ -png_check_chunk_name(png_structrp png_ptr, png_uint_32 chunk_name) +png_check_chunk_name(png_const_structrp png_ptr, const png_uint_32 chunk_name) { int i; + png_uint_32 cn=chunk_name; png_debug(1, "in png_check_chunk_name"); for (i=1; i<=4; ++i) { - int c = chunk_name & 0xff; + int c = cn & 0xff; if (c < 65 || c > 122 || (c > 90 && c < 97)) png_chunk_error(png_ptr, "invalid chunk type"); - chunk_name >>= 8; + cn >>= 8; + } +} + +void /* PRIVATE */ +png_check_chunk_length(png_const_structrp png_ptr, const png_uint_32 length) +{ + png_alloc_size_t limit = PNG_UINT_31_MAX; + +# ifdef PNG_SET_USER_LIMITS_SUPPORTED + if (png_ptr->user_chunk_malloc_max > 0 && + png_ptr->user_chunk_malloc_max < limit) + limit = png_ptr->user_chunk_malloc_max; +# elif PNG_USER_CHUNK_MALLOC_MAX > 0 + if (PNG_USER_CHUNK_MALLOC_MAX < limit) + limit = PNG_USER_CHUNK_MALLOC_MAX; +# endif + if (png_ptr->chunk_name == png_IDAT) + { + png_alloc_size_t idat_limit = PNG_UINT_31_MAX; + size_t row_factor = + (png_ptr->width * png_ptr->channels * (png_ptr->bit_depth > 8? 2: 1) + + 1 + (png_ptr->interlaced? 6: 0)); + if (png_ptr->height > PNG_UINT_32_MAX/row_factor) + idat_limit=PNG_UINT_31_MAX; + else + idat_limit = png_ptr->height * row_factor; + row_factor = row_factor > 32566? 32566 : row_factor; + idat_limit += 6 + 5*(idat_limit/row_factor+1); /* zlib+deflate overhead */ + idat_limit=idat_limit < PNG_UINT_31_MAX? idat_limit : PNG_UINT_31_MAX; + limit = limit < idat_limit? idat_limit : limit; + } + + if (length > limit) + { + png_debug2(0," length = %lu, limit = %lu", + (unsigned long)length,(unsigned long)limit); + png_benign_error(png_ptr, "chunk data is too large"); } } @@ -3097,7 +3220,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display) # ifdef PNG_READ_PACKSWAP_SUPPORTED if ((png_ptr->transformations & PNG_PACKSWAP) != 0) /* little-endian byte */ - end_mask = 0xff << end_mask; + end_mask = (unsigned int)(0xff << end_mask); else /* big-endian byte */ # endif @@ -3371,7 +3494,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display) */ do { - dp[0] = sp[0], dp[1] = sp[1]; + dp[0] = sp[0]; dp[1] = sp[1]; if (row_width <= bytes_to_jump) return; @@ -3392,7 +3515,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display) */ for (;;) { - dp[0] = sp[0], dp[1] = sp[1], dp[2] = sp[2]; + dp[0] = sp[0]; dp[1] = sp[1]; dp[2] = sp[2]; if (row_width <= bytes_to_jump) return; @@ -3418,8 +3541,8 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display) /* Everything is aligned for png_uint_16 copies, but try for * png_uint_32 first. */ - if (png_isaligned(dp, png_uint_32) != 0 && - png_isaligned(sp, png_uint_32) != 0 && + if (png_isaligned(dp, png_uint_32) && + png_isaligned(sp, png_uint_32) && bytes_to_copy % (sizeof (png_uint_32)) == 0 && bytes_to_jump % (sizeof (png_uint_32)) == 0) { @@ -3539,11 +3662,11 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display) #ifdef PNG_READ_INTERLACING_SUPPORTED void /* PRIVATE */ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, - png_uint_32 transformations /* Because these may affect the byte layout */) + png_uint_32 transformations /* Because these may affect the byte layout */) { /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ /* Offset to next interlace block */ - static PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + static PNG_CONST unsigned int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; png_debug(1, "in png_do_read_interlace"); if (row != NULL && row_info != NULL) @@ -3558,9 +3681,10 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, { png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3); png_bytep dp = row + (png_size_t)((final_width - 1) >> 3); - int sshift, dshift; - int s_start, s_end, s_inc; - int jstop = png_pass_inc[pass]; + unsigned int sshift, dshift; + unsigned int s_start, s_end; + int s_inc; + int jstop = (int)png_pass_inc[pass]; png_byte v; png_uint_32 i; int j; @@ -3568,8 +3692,8 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, #ifdef PNG_READ_PACKSWAP_SUPPORTED if ((transformations & PNG_PACKSWAP) != 0) { - sshift = (int)((row_info->width + 7) & 0x07); - dshift = (int)((final_width + 7) & 0x07); + sshift = ((row_info->width + 7) & 0x07); + dshift = ((final_width + 7) & 0x07); s_start = 7; s_end = 0; s_inc = -1; @@ -3578,8 +3702,8 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, else #endif { - sshift = 7 - (int)((row_info->width + 7) & 0x07); - dshift = 7 - (int)((final_width + 7) & 0x07); + sshift = 7 - ((row_info->width + 7) & 0x07); + dshift = 7 - ((final_width + 7) & 0x07); s_start = 0; s_end = 7; s_inc = 1; @@ -3591,7 +3715,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, for (j = 0; j < jstop; j++) { unsigned int tmp = *dp & (0x7f7f >> (7 - dshift)); - tmp |= v << dshift; + tmp |= (unsigned int)(v << dshift); *dp = (png_byte)(tmp & 0xff); if (dshift == s_end) @@ -3601,7 +3725,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, } else - dshift += s_inc; + dshift = (unsigned int)((int)dshift + s_inc); } if (sshift == s_end) @@ -3611,7 +3735,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, } else - sshift += s_inc; + sshift = (unsigned int)((int)sshift + s_inc); } break; } @@ -3620,16 +3744,17 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, { png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2); png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2); - int sshift, dshift; - int s_start, s_end, s_inc; - int jstop = png_pass_inc[pass]; + unsigned int sshift, dshift; + unsigned int s_start, s_end; + int s_inc; + int jstop = (int)png_pass_inc[pass]; png_uint_32 i; #ifdef PNG_READ_PACKSWAP_SUPPORTED if ((transformations & PNG_PACKSWAP) != 0) { - sshift = (int)(((row_info->width + 3) & 0x03) << 1); - dshift = (int)(((final_width + 3) & 0x03) << 1); + sshift = (((row_info->width + 3) & 0x03) << 1); + dshift = (((final_width + 3) & 0x03) << 1); s_start = 6; s_end = 0; s_inc = -2; @@ -3638,8 +3763,8 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, else #endif { - sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1); - dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1); + sshift = ((3 - ((row_info->width + 3) & 0x03)) << 1); + dshift = ((3 - ((final_width + 3) & 0x03)) << 1); s_start = 0; s_end = 6; s_inc = 2; @@ -3654,7 +3779,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, for (j = 0; j < jstop; j++) { unsigned int tmp = *dp & (0x3f3f >> (6 - dshift)); - tmp |= v << dshift; + tmp |= (unsigned int)(v << dshift); *dp = (png_byte)(tmp & 0xff); if (dshift == s_end) @@ -3664,7 +3789,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, } else - dshift += s_inc; + dshift = (unsigned int)((int)dshift + s_inc); } if (sshift == s_end) @@ -3674,7 +3799,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, } else - sshift += s_inc; + sshift = (unsigned int)((int)sshift + s_inc); } break; } @@ -3683,16 +3808,17 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, { png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1); png_bytep dp = row + (png_size_t)((final_width - 1) >> 1); - int sshift, dshift; - int s_start, s_end, s_inc; + unsigned int sshift, dshift; + unsigned int s_start, s_end; + int s_inc; png_uint_32 i; - int jstop = png_pass_inc[pass]; + int jstop = (int)png_pass_inc[pass]; #ifdef PNG_READ_PACKSWAP_SUPPORTED if ((transformations & PNG_PACKSWAP) != 0) { - sshift = (int)(((row_info->width + 1) & 0x01) << 2); - dshift = (int)(((final_width + 1) & 0x01) << 2); + sshift = (((row_info->width + 1) & 0x01) << 2); + dshift = (((final_width + 1) & 0x01) << 2); s_start = 4; s_end = 0; s_inc = -4; @@ -3701,8 +3827,8 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, else #endif { - sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2); - dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2); + sshift = ((1 - ((row_info->width + 1) & 0x01)) << 2); + dshift = ((1 - ((final_width + 1) & 0x01)) << 2); s_start = 0; s_end = 4; s_inc = 4; @@ -3716,7 +3842,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, for (j = 0; j < jstop; j++) { unsigned int tmp = *dp & (0xf0f >> (4 - dshift)); - tmp |= v << dshift; + tmp |= (unsigned int)(v << dshift); *dp = (png_byte)(tmp & 0xff); if (dshift == s_end) @@ -3726,7 +3852,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, } else - dshift += s_inc; + dshift = (unsigned int)((int)dshift + s_inc); } if (sshift == s_end) @@ -3736,7 +3862,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, } else - sshift += s_inc; + sshift = (unsigned int)((int)sshift + s_inc); } break; } @@ -3750,7 +3876,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes; - int jstop = png_pass_inc[pass]; + int jstop = (int)png_pass_inc[pass]; png_uint_32 i; for (i = 0; i < row_info->width; i++) @@ -3783,7 +3909,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, static void png_read_filter_row_sub(png_row_infop row_info, png_bytep row, - png_const_bytep prev_row) + png_const_bytep prev_row) { png_size_t i; png_size_t istop = row_info->rowbytes; @@ -3801,7 +3927,7 @@ png_read_filter_row_sub(png_row_infop row_info, png_bytep row, static void png_read_filter_row_up(png_row_infop row_info, png_bytep row, - png_const_bytep prev_row) + png_const_bytep prev_row) { png_size_t i; png_size_t istop = row_info->rowbytes; @@ -3817,7 +3943,7 @@ png_read_filter_row_up(png_row_infop row_info, png_bytep row, static void png_read_filter_row_avg(png_row_infop row_info, png_bytep row, - png_const_bytep prev_row) + png_const_bytep prev_row) { png_size_t i; png_bytep rp = row; @@ -3844,7 +3970,7 @@ png_read_filter_row_avg(png_row_infop row_info, png_bytep row, static void png_read_filter_row_paeth_1byte_pixel(png_row_infop row_info, png_bytep row, - png_const_bytep prev_row) + png_const_bytep prev_row) { png_bytep rp_end = row + row_info->rowbytes; int a, c; @@ -3878,7 +4004,10 @@ png_read_filter_row_paeth_1byte_pixel(png_row_infop row_info, png_bytep row, /* Find the best predictor, the least of pa, pb, pc favoring the earlier * ones in the case of a tie. */ - if (pb < pa) pa = pb, a = b; + if (pb < pa) + { + pa = pb; a = b; + } if (pc < pa) a = c; /* Calculate the current pixel in a, and move the previous row pixel to c @@ -3892,9 +4021,9 @@ png_read_filter_row_paeth_1byte_pixel(png_row_infop row_info, png_bytep row, static void png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row, - png_const_bytep prev_row) + png_const_bytep prev_row) { - int bpp = (row_info->pixel_depth + 7) >> 3; + unsigned int bpp = (row_info->pixel_depth + 7) >> 3; png_bytep rp_end = row + bpp; /* Process the first pixel in the row completely (this is the same as 'up' @@ -3907,7 +4036,7 @@ png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row, } /* Remainder */ - rp_end += row_info->rowbytes - bpp; + rp_end = rp_end + (row_info->rowbytes - bpp); while (row < rp_end) { @@ -3930,7 +4059,10 @@ png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row, pc = (p + pc) < 0 ? -(p + pc) : p + pc; #endif - if (pb < pa) pa = pb, a = b; + if (pb < pa) + { + pa = pb; a = b; + } if (pc < pa) a = c; a += *row; @@ -3977,7 +4109,7 @@ png_init_filter_functions(png_structrp pp) void /* PRIVATE */ png_read_filter_row(png_structrp pp, png_row_infop row_info, png_bytep row, - png_const_bytep prev_row, int filter) + png_const_bytep prev_row, int filter) { /* OPTIMIZATION: DO NOT MODIFY THIS FUNCTION, instead #define * PNG_FILTER_OPTIMIZATIONS to a function that overrides the generic @@ -3995,7 +4127,7 @@ png_read_filter_row(png_structrp pp, png_row_infop row_info, png_bytep row, #ifdef PNG_SEQUENTIAL_READ_SUPPORTED void /* PRIVATE */ png_read_IDAT_data(png_structrp png_ptr, png_bytep output, - png_alloc_size_t avail_out) + png_alloc_size_t avail_out) { /* Loop reading IDATs and decompressing the result into output[avail_out] */ png_ptr->zstream.next_out = output; @@ -4252,7 +4384,7 @@ png_read_start_row(png_structrp png_ptr) /* Offset to next interlace block in the y direction */ static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; - int max_pixel_depth; + unsigned int max_pixel_depth; png_size_t row_bytes; png_debug(1, "in png_read_start_row"); @@ -4281,7 +4413,7 @@ png_read_start_row(png_structrp png_ptr) png_ptr->iwidth = png_ptr->width; } - max_pixel_depth = png_ptr->pixel_depth; + max_pixel_depth = (unsigned int)png_ptr->pixel_depth; /* WARNING: * png_read_transform_info (pngrtran.c) performs a simpler set of * calculations to calculate the final pixel depth, then @@ -4416,7 +4548,7 @@ png_read_start_row(png_structrp png_ptr) defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) if ((png_ptr->transformations & PNG_USER_TRANSFORM) != 0) { - int user_pixel_depth = png_ptr->user_transform_depth * + unsigned int user_pixel_depth = png_ptr->user_transform_depth * png_ptr->user_transform_channels; if (user_pixel_depth > max_pixel_depth) @@ -4438,7 +4570,7 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) * for safety's sake */ row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) + - 1 + ((max_pixel_depth + 7) >> 3); + 1 + ((max_pixel_depth + 7) >> 3U); #ifdef PNG_MAX_MALLOC_64K if (row_bytes > (png_uint_32)65536L) @@ -4447,42 +4579,42 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) if (row_bytes + 48 > png_ptr->old_big_row_buf_size) { - png_free(png_ptr, png_ptr->big_row_buf); - png_free(png_ptr, png_ptr->big_prev_row); + png_free(png_ptr, png_ptr->big_row_buf); + png_free(png_ptr, png_ptr->big_prev_row); - if (png_ptr->interlaced != 0) - png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr, - row_bytes + 48); + if (png_ptr->interlaced != 0) + png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr, + row_bytes + 48); - else - png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 48); + else + png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 48); - png_ptr->big_prev_row = (png_bytep)png_malloc(png_ptr, row_bytes + 48); + png_ptr->big_prev_row = (png_bytep)png_malloc(png_ptr, row_bytes + 48); #ifdef PNG_ALIGNED_MEMORY_SUPPORTED - /* Use 16-byte aligned memory for row_buf with at least 16 bytes - * of padding before and after row_buf; treat prev_row similarly. - * NOTE: the alignment is to the start of the pixels, one beyond the start - * of the buffer, because of the filter byte. Prior to libpng 1.5.6 this - * was incorrect; the filter byte was aligned, which had the exact - * opposite effect of that intended. - */ - { - png_bytep temp = png_ptr->big_row_buf + 32; - int extra = (int)((temp - (png_bytep)0) & 0x0f); - png_ptr->row_buf = temp - extra - 1/*filter byte*/; - - temp = png_ptr->big_prev_row + 32; - extra = (int)((temp - (png_bytep)0) & 0x0f); - png_ptr->prev_row = temp - extra - 1/*filter byte*/; - } + /* Use 16-byte aligned memory for row_buf with at least 16 bytes + * of padding before and after row_buf; treat prev_row similarly. + * NOTE: the alignment is to the start of the pixels, one beyond the start + * of the buffer, because of the filter byte. Prior to libpng 1.5.6 this + * was incorrect; the filter byte was aligned, which had the exact + * opposite effect of that intended. + */ + { + png_bytep temp = png_ptr->big_row_buf + 32; + int extra = (int)((temp - (png_bytep)0) & 0x0f); + png_ptr->row_buf = temp - extra - 1/*filter byte*/; + + temp = png_ptr->big_prev_row + 32; + extra = (int)((temp - (png_bytep)0) & 0x0f); + png_ptr->prev_row = temp - extra - 1/*filter byte*/; + } #else - /* Use 31 bytes of padding before and 17 bytes after row_buf. */ - png_ptr->row_buf = png_ptr->big_row_buf + 31; - png_ptr->prev_row = png_ptr->big_prev_row + 31; + /* Use 31 bytes of padding before and 17 bytes after row_buf. */ + png_ptr->row_buf = png_ptr->big_row_buf + 31; + png_ptr->prev_row = png_ptr->big_prev_row + 31; #endif - png_ptr->old_big_row_buf_size = row_bytes + 48; + png_ptr->old_big_row_buf_size = row_bytes + 48; } #ifdef PNG_MAX_MALLOC_64K @@ -4507,7 +4639,7 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) * does not, so free the read buffer now regardless; the sequential reader * reallocates it on demand. */ - if (png_ptr->read_buffer != 0) + if (png_ptr->read_buffer != NULL) { png_bytep buffer = png_ptr->read_buffer; |