| From 1044b43637fa7f70fb19b93593777b78bd20da86 Mon Sep 17 00:00:00 2001 |
| From: erouault <erouault> |
| Date: Fri, 2 Dec 2016 23:05:51 +0000 |
| Subject: [PATCH] * libtiff/tif_pixarlog.c, libtiff/tif_luv.c: fix heap-based |
| buffer overflow on generation of PixarLog / LUV compressed files, with |
| ColorMap, TransferFunction attached and nasty plays with bitspersample. The |
| fix for LUV has not been tested, but suffers from the same kind of issue of |
| PixarLog. Reported by Agostino Sarubbo. Fixes |
| http://bugzilla.maptools.org/show_bug.cgi?id=2604 |
| |
| Fixes CVE-2016-10269 |
| |
| Signed-off-by: Peter Korsgaard <peter@korsgaard.com> |
| --- |
| libtiff/tif_luv.c | 18 ++++++++++++++---- |
| libtiff/tif_pixarlog.c | 17 +++++++++++++++-- |
| 2 files changed, 39 insertions(+), 6 deletions(-) |
| |
| diff --git a/libtiff/tif_luv.c b/libtiff/tif_luv.c |
| index f68a9b13..e6783db5 100644 |
| --- a/libtiff/tif_luv.c |
| +++ b/libtiff/tif_luv.c |
| @@ -158,6 +158,7 @@ |
| typedef struct logLuvState LogLuvState; |
| |
| struct logLuvState { |
| + int encoder_state; /* 1 if encoder correctly initialized */ |
| int user_datafmt; /* user data format */ |
| int encode_meth; /* encoding method */ |
| int pixel_size; /* bytes per pixel */ |
| @@ -1552,6 +1553,7 @@ LogLuvSetupEncode(TIFF* tif) |
| td->td_photometric, "must be either LogLUV or LogL"); |
| break; |
| } |
| + sp->encoder_state = 1; |
| return (1); |
| notsupported: |
| TIFFErrorExt(tif->tif_clientdata, module, |
| @@ -1563,19 +1565,27 @@ notsupported: |
| static void |
| LogLuvClose(TIFF* tif) |
| { |
| + LogLuvState* sp = (LogLuvState*) tif->tif_data; |
| TIFFDirectory *td = &tif->tif_dir; |
| |
| + assert(sp != 0); |
| /* |
| * For consistency, we always want to write out the same |
| * bitspersample and sampleformat for our TIFF file, |
| * regardless of the data format being used by the application. |
| * Since this routine is called after tags have been set but |
| * before they have been recorded in the file, we reset them here. |
| + * Note: this is really a nasty approach. See PixarLogClose |
| */ |
| - td->td_samplesperpixel = |
| - (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3; |
| - td->td_bitspersample = 16; |
| - td->td_sampleformat = SAMPLEFORMAT_INT; |
| + if( sp->encoder_state ) |
| + { |
| + /* See PixarLogClose. Might avoid issues with tags whose size depends |
| + * on those below, but not completely sure this is enough. */ |
| + td->td_samplesperpixel = |
| + (td->td_photometric == PHOTOMETRIC_LOGL) ? 1 : 3; |
| + td->td_bitspersample = 16; |
| + td->td_sampleformat = SAMPLEFORMAT_INT; |
| + } |
| } |
| |
| static void |
| diff --git a/libtiff/tif_pixarlog.c b/libtiff/tif_pixarlog.c |
| index d1246c3d..aa99bc92 100644 |
| --- a/libtiff/tif_pixarlog.c |
| +++ b/libtiff/tif_pixarlog.c |
| @@ -1233,8 +1233,10 @@ PixarLogPostEncode(TIFF* tif) |
| static void |
| PixarLogClose(TIFF* tif) |
| { |
| + PixarLogState* sp = (PixarLogState*) tif->tif_data; |
| TIFFDirectory *td = &tif->tif_dir; |
| |
| + assert(sp != 0); |
| /* In a really sneaky (and really incorrect, and untruthful, and |
| * troublesome, and error-prone) maneuver that completely goes against |
| * the spirit of TIFF, and breaks TIFF, on close, we covertly |
| @@ -1243,8 +1245,19 @@ PixarLogClose(TIFF* tif) |
| * readers that don't know about PixarLog, or how to set |
| * the PIXARLOGDATFMT pseudo-tag. |
| */ |
| - td->td_bitspersample = 8; |
| - td->td_sampleformat = SAMPLEFORMAT_UINT; |
| + |
| + if (sp->state&PLSTATE_INIT) { |
| + /* We test the state to avoid an issue such as in |
| + * http://bugzilla.maptools.org/show_bug.cgi?id=2604 |
| + * What appends in that case is that the bitspersample is 1 and |
| + * a TransferFunction is set. The size of the TransferFunction |
| + * depends on 1<<bitspersample. So if we increase it, an access |
| + * out of the buffer will happen at directory flushing. |
| + * Another option would be to clear those targs. |
| + */ |
| + td->td_bitspersample = 8; |
| + td->td_sampleformat = SAMPLEFORMAT_UINT; |
| + } |
| } |
| |
| static void |
| -- |
| 2.11.0 |
| |
