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| author | Wan-Teh Chang <wtc@google.com> | 2023-06-15 11:34:22 -0700 |
|---|---|---|
| committer | Cosmin Truta <ctruta@gmail.com> | 2023-06-20 19:20:38 +0300 |
| commit | 8be5c147d567bf90553088305208e612abb16768 (patch) | |
| tree | bd6778500209cdcae339fb62b727dec8c5ba883c | |
| parent | f7abe3c4199a0fd98f62193ed2cb5337ae44959b (diff) | |
| download | libpng-8be5c147d567bf90553088305208e612abb16768.tar.gz | |
Don't report a valid tRNS chunk if it was canceled
Add special handling of the PNG_INFO_tRNS flag to png_get_valid() to
not report a canceled tRNS chunk as valid.
Fix https://github.com/glennrp/libpng/issues/482
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
| -rw-r--r-- | AUTHORS | 1 | ||||
| -rw-r--r-- | pngget.c | 13 |
2 files changed, 13 insertions, 1 deletions
@@ -41,6 +41,7 @@ Authors, for copyright and licensing purposes. - Matt Sarett - Mike Klein - Sami Boukortt + - Wan-Teh Chang The build projects, the build scripts, the test scripts, and other files in the "ci", "projects", "scripts" and "tests" directories, have @@ -1,7 +1,7 @@ /* pngget.c - retrieval of values from info struct * - * Copyright (c) 2018 Cosmin Truta + * Copyright (c) 2018-2023 Cosmin Truta * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson * Copyright (c) 1996-1997 Andreas Dilger * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. @@ -21,7 +21,18 @@ png_get_valid(png_const_structrp png_ptr, png_const_inforp info_ptr, png_uint_32 flag) { if (png_ptr != NULL && info_ptr != NULL) + { +#ifdef PNG_READ_tRNS_SUPPORTED + /* png_handle_PLTE() may have canceled a valid tRNS chunk but left the + * 'valid' flag for the detection of duplicate chunks. Do not report a + * valid tRNS chunk in this case. + */ + if (flag == PNG_INFO_tRNS && png_ptr->num_trans == 0) + return(0); +#endif + return(info_ptr->valid & flag); + } return(0); } |