Patrick Williams | 2390b1b | 2022-11-03 13:47:49 -0500 | [diff] [blame] | 1 | CVE: CVE-2022-3599 |
| 2 | Upstream-Status: Backport |
| 3 | Signed-off-by: Ross Burton <ross.burton@arm.com> |
| 4 | |
| 5 | From f00484b9519df933723deb38fff943dc291a793d Mon Sep 17 00:00:00 2001 |
| 6 | From: Su_Laus <sulau@freenet.de> |
| 7 | Date: Tue, 30 Aug 2022 16:56:48 +0200 |
| 8 | Subject: [PATCH] Revised handling of TIFFTAG_INKNAMES and related |
| 9 | TIFFTAG_NUMBEROFINKS value |
| 10 | |
| 11 | In order to solve the buffer overflow issues related to TIFFTAG_INKNAMES and related TIFFTAG_NUMBEROFINKS value, a revised handling of those tags within LibTiff is proposed: |
| 12 | |
| 13 | Behaviour for writing: |
| 14 | `NumberOfInks` MUST fit to the number of inks in the `InkNames` string. |
| 15 | `NumberOfInks` is automatically set when `InkNames` is set. |
| 16 | If `NumberOfInks` is different to the number of inks within `InkNames` string, that will be corrected and a warning is issued. |
| 17 | If `NumberOfInks` is not equal to samplesperpixel only a warning will be issued. |
| 18 | |
| 19 | Behaviour for reading: |
| 20 | When reading `InkNames` from a TIFF file, the `NumberOfInks` will be set automatically to the number of inks in `InkNames` string. |
| 21 | If `NumberOfInks` is different to the number of inks within `InkNames` string, that will be corrected and a warning is issued. |
| 22 | If `NumberOfInks` is not equal to samplesperpixel only a warning will be issued. |
| 23 | |
| 24 | This allows the safe use of the NumberOfInks value to read out the InkNames without buffer overflow |
| 25 | |
| 26 | This MR will close the following issues: #149, #150, #152, #168 (to be checked), #250, #269, #398 and #456. |
| 27 | |
| 28 | It also fixes the old bug at http://bugzilla.maptools.org/show_bug.cgi?id=2599, for which the limitation of `NumberOfInks = SPP` was introduced, which is in my opinion not necessary and does not solve the general issue. |
| 29 | --- |
| 30 | libtiff/tif_dir.c | 119 ++++++++++++++++++++++++----------------- |
| 31 | libtiff/tif_dir.h | 2 + |
| 32 | libtiff/tif_dirinfo.c | 2 +- |
| 33 | libtiff/tif_dirwrite.c | 5 ++ |
| 34 | libtiff/tif_print.c | 4 ++ |
| 35 | 5 files changed, 82 insertions(+), 50 deletions(-) |
| 36 | |
| 37 | diff --git a/libtiff/tif_dir.c b/libtiff/tif_dir.c |
| 38 | index 793e8a79..816f7756 100644 |
| 39 | --- a/libtiff/tif_dir.c |
| 40 | +++ b/libtiff/tif_dir.c |
| 41 | @@ -136,32 +136,30 @@ setExtraSamples(TIFF* tif, va_list ap, uint32_t* v) |
| 42 | } |
| 43 | |
| 44 | /* |
| 45 | - * Confirm we have "samplesperpixel" ink names separated by \0. Returns |
| 46 | + * Count ink names separated by \0. Returns |
| 47 | * zero if the ink names are not as expected. |
| 48 | */ |
| 49 | -static uint32_t |
| 50 | -checkInkNamesString(TIFF* tif, uint32_t slen, const char* s) |
| 51 | +static uint16_t |
| 52 | +countInkNamesString(TIFF *tif, uint32_t slen, const char *s) |
| 53 | { |
| 54 | - TIFFDirectory* td = &tif->tif_dir; |
| 55 | - uint16_t i = td->td_samplesperpixel; |
| 56 | + uint16_t i = 0; |
| 57 | + const char *ep = s + slen; |
| 58 | + const char *cp = s; |
| 59 | |
| 60 | if (slen > 0) { |
| 61 | - const char* ep = s+slen; |
| 62 | - const char* cp = s; |
| 63 | - for (; i > 0; i--) { |
| 64 | + do { |
| 65 | for (; cp < ep && *cp != '\0'; cp++) {} |
| 66 | if (cp >= ep) |
| 67 | goto bad; |
| 68 | cp++; /* skip \0 */ |
| 69 | - } |
| 70 | - return ((uint32_t)(cp - s)); |
| 71 | + i++; |
| 72 | + } while (cp < ep); |
| 73 | + return (i); |
| 74 | } |
| 75 | bad: |
| 76 | TIFFErrorExt(tif->tif_clientdata, "TIFFSetField", |
| 77 | - "%s: Invalid InkNames value; expecting %"PRIu16" names, found %"PRIu16, |
| 78 | - tif->tif_name, |
| 79 | - td->td_samplesperpixel, |
| 80 | - (uint16_t)(td->td_samplesperpixel-i)); |
| 81 | + "%s: Invalid InkNames value; no NUL at given buffer end location %"PRIu32", after %"PRIu16" ink", |
| 82 | + tif->tif_name, slen, i); |
| 83 | return (0); |
| 84 | } |
| 85 | |
| 86 | @@ -478,13 +476,61 @@ _TIFFVSetField(TIFF* tif, uint32_t tag, va_list ap) |
| 87 | _TIFFsetFloatArray(&td->td_refblackwhite, va_arg(ap, float*), 6); |
| 88 | break; |
| 89 | case TIFFTAG_INKNAMES: |
| 90 | - v = (uint16_t) va_arg(ap, uint16_vap); |
| 91 | - s = va_arg(ap, char*); |
| 92 | - v = checkInkNamesString(tif, v, s); |
| 93 | - status = v > 0; |
| 94 | - if( v > 0 ) { |
| 95 | - _TIFFsetNString(&td->td_inknames, s, v); |
| 96 | - td->td_inknameslen = v; |
| 97 | + { |
| 98 | + v = (uint16_t) va_arg(ap, uint16_vap); |
| 99 | + s = va_arg(ap, char*); |
| 100 | + uint16_t ninksinstring; |
| 101 | + ninksinstring = countInkNamesString(tif, v, s); |
| 102 | + status = ninksinstring > 0; |
| 103 | + if(ninksinstring > 0 ) { |
| 104 | + _TIFFsetNString(&td->td_inknames, s, v); |
| 105 | + td->td_inknameslen = v; |
| 106 | + /* Set NumberOfInks to the value ninksinstring */ |
| 107 | + if (TIFFFieldSet(tif, FIELD_NUMBEROFINKS)) |
| 108 | + { |
| 109 | + if (td->td_numberofinks != ninksinstring) { |
| 110 | + TIFFErrorExt(tif->tif_clientdata, module, |
| 111 | + "Warning %s; Tag %s:\n Value %"PRIu16" of NumberOfInks is different from the number of inks %"PRIu16".\n -> NumberOfInks value adapted to %"PRIu16"", |
| 112 | + tif->tif_name, fip->field_name, td->td_numberofinks, ninksinstring, ninksinstring); |
| 113 | + td->td_numberofinks = ninksinstring; |
| 114 | + } |
| 115 | + } else { |
| 116 | + td->td_numberofinks = ninksinstring; |
| 117 | + TIFFSetFieldBit(tif, FIELD_NUMBEROFINKS); |
| 118 | + } |
| 119 | + if (TIFFFieldSet(tif, FIELD_SAMPLESPERPIXEL)) |
| 120 | + { |
| 121 | + if (td->td_numberofinks != td->td_samplesperpixel) { |
| 122 | + TIFFErrorExt(tif->tif_clientdata, module, |
| 123 | + "Warning %s; Tag %s:\n Value %"PRIu16" of NumberOfInks is different from the SamplesPerPixel value %"PRIu16"", |
| 124 | + tif->tif_name, fip->field_name, td->td_numberofinks, td->td_samplesperpixel); |
| 125 | + } |
| 126 | + } |
| 127 | + } |
| 128 | + } |
| 129 | + break; |
| 130 | + case TIFFTAG_NUMBEROFINKS: |
| 131 | + v = (uint16_t)va_arg(ap, uint16_vap); |
| 132 | + /* If InkNames already set also NumberOfInks is set accordingly and should be equal */ |
| 133 | + if (TIFFFieldSet(tif, FIELD_INKNAMES)) |
| 134 | + { |
| 135 | + if (v != td->td_numberofinks) { |
| 136 | + TIFFErrorExt(tif->tif_clientdata, module, |
| 137 | + "Error %s; Tag %s:\n It is not possible to set the value %"PRIu32" for NumberOfInks\n which is different from the number of inks in the InkNames tag (%"PRIu16")", |
| 138 | + tif->tif_name, fip->field_name, v, td->td_numberofinks); |
| 139 | + /* Do not set / overwrite number of inks already set by InkNames case accordingly. */ |
| 140 | + status = 0; |
| 141 | + } |
| 142 | + } else { |
| 143 | + td->td_numberofinks = (uint16_t)v; |
| 144 | + if (TIFFFieldSet(tif, FIELD_SAMPLESPERPIXEL)) |
| 145 | + { |
| 146 | + if (td->td_numberofinks != td->td_samplesperpixel) { |
| 147 | + TIFFErrorExt(tif->tif_clientdata, module, |
| 148 | + "Warning %s; Tag %s:\n Value %"PRIu32" of NumberOfInks is different from the SamplesPerPixel value %"PRIu16"", |
| 149 | + tif->tif_name, fip->field_name, v, td->td_samplesperpixel); |
| 150 | + } |
| 151 | + } |
| 152 | } |
| 153 | break; |
| 154 | case TIFFTAG_PERSAMPLE: |
| 155 | @@ -986,34 +1032,6 @@ _TIFFVGetField(TIFF* tif, uint32_t tag, va_list ap) |
| 156 | if (fip->field_bit == FIELD_CUSTOM) { |
| 157 | standard_tag = 0; |
| 158 | } |
| 159 | - |
| 160 | - if( standard_tag == TIFFTAG_NUMBEROFINKS ) |
| 161 | - { |
| 162 | - int i; |
| 163 | - for (i = 0; i < td->td_customValueCount; i++) { |
| 164 | - uint16_t val; |
| 165 | - TIFFTagValue *tv = td->td_customValues + i; |
| 166 | - if (tv->info->field_tag != standard_tag) |
| 167 | - continue; |
| 168 | - if( tv->value == NULL ) |
| 169 | - return 0; |
| 170 | - val = *(uint16_t *)tv->value; |
| 171 | - /* Truncate to SamplesPerPixel, since the */ |
| 172 | - /* setting code for INKNAMES assume that there are SamplesPerPixel */ |
| 173 | - /* inknames. */ |
| 174 | - /* Fixes http://bugzilla.maptools.org/show_bug.cgi?id=2599 */ |
| 175 | - if( val > td->td_samplesperpixel ) |
| 176 | - { |
| 177 | - TIFFWarningExt(tif->tif_clientdata,"_TIFFVGetField", |
| 178 | - "Truncating NumberOfInks from %u to %"PRIu16, |
| 179 | - val, td->td_samplesperpixel); |
| 180 | - val = td->td_samplesperpixel; |
| 181 | - } |
| 182 | - *va_arg(ap, uint16_t*) = val; |
| 183 | - return 1; |
| 184 | - } |
| 185 | - return 0; |
| 186 | - } |
| 187 | |
| 188 | switch (standard_tag) { |
| 189 | case TIFFTAG_SUBFILETYPE: |
| 190 | @@ -1195,6 +1213,9 @@ _TIFFVGetField(TIFF* tif, uint32_t tag, va_list ap) |
| 191 | case TIFFTAG_INKNAMES: |
| 192 | *va_arg(ap, const char**) = td->td_inknames; |
| 193 | break; |
| 194 | + case TIFFTAG_NUMBEROFINKS: |
| 195 | + *va_arg(ap, uint16_t *) = td->td_numberofinks; |
| 196 | + break; |
| 197 | default: |
| 198 | { |
| 199 | int i; |
| 200 | diff --git a/libtiff/tif_dir.h b/libtiff/tif_dir.h |
| 201 | index 09065648..0c251c9e 100644 |
| 202 | --- a/libtiff/tif_dir.h |
| 203 | +++ b/libtiff/tif_dir.h |
| 204 | @@ -117,6 +117,7 @@ typedef struct { |
| 205 | /* CMYK parameters */ |
| 206 | int td_inknameslen; |
| 207 | char* td_inknames; |
| 208 | + uint16_t td_numberofinks; /* number of inks in InkNames string */ |
| 209 | |
| 210 | int td_customValueCount; |
| 211 | TIFFTagValue *td_customValues; |
| 212 | @@ -174,6 +175,7 @@ typedef struct { |
| 213 | #define FIELD_TRANSFERFUNCTION 44 |
| 214 | #define FIELD_INKNAMES 46 |
| 215 | #define FIELD_SUBIFD 49 |
| 216 | +#define FIELD_NUMBEROFINKS 50 |
| 217 | /* FIELD_CUSTOM (see tiffio.h) 65 */ |
| 218 | /* end of support for well-known tags; codec-private tags follow */ |
| 219 | #define FIELD_CODEC 66 /* base of codec-private tags */ |
| 220 | diff --git a/libtiff/tif_dirinfo.c b/libtiff/tif_dirinfo.c |
| 221 | index 3371cb5c..3b4bcd33 100644 |
| 222 | --- a/libtiff/tif_dirinfo.c |
| 223 | +++ b/libtiff/tif_dirinfo.c |
| 224 | @@ -114,7 +114,7 @@ tiffFields[] = { |
| 225 | { TIFFTAG_SUBIFD, -1, -1, TIFF_IFD8, 0, TIFF_SETGET_C16_IFD8, TIFF_SETGET_UNDEFINED, FIELD_SUBIFD, 1, 1, "SubIFD", (TIFFFieldArray*) &tiffFieldArray }, |
| 226 | { TIFFTAG_INKSET, 1, 1, TIFF_SHORT, 0, TIFF_SETGET_UINT16, TIFF_SETGET_UNDEFINED, FIELD_CUSTOM, 0, 0, "InkSet", NULL }, |
| 227 | { TIFFTAG_INKNAMES, -1, -1, TIFF_ASCII, 0, TIFF_SETGET_C16_ASCII, TIFF_SETGET_UNDEFINED, FIELD_INKNAMES, 1, 1, "InkNames", NULL }, |
| 228 | - { TIFFTAG_NUMBEROFINKS, 1, 1, TIFF_SHORT, 0, TIFF_SETGET_UINT16, TIFF_SETGET_UNDEFINED, FIELD_CUSTOM, 1, 0, "NumberOfInks", NULL }, |
| 229 | + { TIFFTAG_NUMBEROFINKS, 1, 1, TIFF_SHORT, 0, TIFF_SETGET_UINT16, TIFF_SETGET_UNDEFINED, FIELD_NUMBEROFINKS, 1, 0, "NumberOfInks", NULL }, |
| 230 | { TIFFTAG_DOTRANGE, 2, 2, TIFF_SHORT, 0, TIFF_SETGET_UINT16_PAIR, TIFF_SETGET_UNDEFINED, FIELD_CUSTOM, 0, 0, "DotRange", NULL }, |
| 231 | { TIFFTAG_TARGETPRINTER, -1, -1, TIFF_ASCII, 0, TIFF_SETGET_ASCII, TIFF_SETGET_UNDEFINED, FIELD_CUSTOM, 1, 0, "TargetPrinter", NULL }, |
| 232 | { TIFFTAG_EXTRASAMPLES, -1, -1, TIFF_SHORT, 0, TIFF_SETGET_C16_UINT16, TIFF_SETGET_UNDEFINED, FIELD_EXTRASAMPLES, 0, 1, "ExtraSamples", NULL }, |
| 233 | diff --git a/libtiff/tif_dirwrite.c b/libtiff/tif_dirwrite.c |
| 234 | index 6c86fdca..062e4610 100644 |
| 235 | --- a/libtiff/tif_dirwrite.c |
| 236 | +++ b/libtiff/tif_dirwrite.c |
| 237 | @@ -626,6 +626,11 @@ TIFFWriteDirectorySec(TIFF* tif, int isimage, int imagedone, uint64_t* pdiroff) |
| 238 | if (!TIFFWriteDirectoryTagAscii(tif,&ndir,dir,TIFFTAG_INKNAMES,tif->tif_dir.td_inknameslen,tif->tif_dir.td_inknames)) |
| 239 | goto bad; |
| 240 | } |
| 241 | + if (TIFFFieldSet(tif, FIELD_NUMBEROFINKS)) |
| 242 | + { |
| 243 | + if (!TIFFWriteDirectoryTagShort(tif, &ndir, dir, TIFFTAG_NUMBEROFINKS, tif->tif_dir.td_numberofinks)) |
| 244 | + goto bad; |
| 245 | + } |
| 246 | if (TIFFFieldSet(tif,FIELD_SUBIFD)) |
| 247 | { |
| 248 | if (!TIFFWriteDirectoryTagSubifd(tif,&ndir,dir)) |
| 249 | diff --git a/libtiff/tif_print.c b/libtiff/tif_print.c |
| 250 | index 16ce5780..a91b9e7b 100644 |
| 251 | --- a/libtiff/tif_print.c |
| 252 | +++ b/libtiff/tif_print.c |
| 253 | @@ -397,6 +397,10 @@ TIFFPrintDirectory(TIFF* tif, FILE* fd, long flags) |
| 254 | } |
| 255 | fputs("\n", fd); |
| 256 | } |
| 257 | + if (TIFFFieldSet(tif, FIELD_NUMBEROFINKS)) { |
| 258 | + fprintf(fd, " NumberOfInks: %d\n", |
| 259 | + td->td_numberofinks); |
| 260 | + } |
| 261 | if (TIFFFieldSet(tif,FIELD_THRESHHOLDING)) { |
| 262 | fprintf(fd, " Thresholding: "); |
| 263 | switch (td->td_threshholding) { |
| 264 | -- |
| 265 | 2.34.1 |
| 266 | |