avcodec/tiff: Fix handling of av_strdup() failures

For unknown geokey values, get_geokey_val() returns
"Unknown-%d" with val being used for %d. This string
is allocated and therefore all the known geokey values
(static strings) are strdup'ed. In case this fails
it is either ignored or treated as "Unknown-%d".
(Furthermore it is possible to call av_strdup(NULL),
although this is not documented to be legal.)

This commit changes this by only returning the static strings
in get_geokey_val(); the unknown handling and strdup'ing
is moved out of it.

Reviewed-by: Stefano Sabatini <stefasab@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit is contained in:
Andreas Rheinhardt 2024-03-09 13:40:19 +01:00
parent 4027c2e1d0
commit 9b9b574191

View File

@ -36,6 +36,7 @@
#include <float.h>
#include "libavutil/attributes.h"
#include "libavutil/avstring.h"
#include "libavutil/error.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/opt.h"
@ -179,19 +180,17 @@ static const char *search_keyval(const TiffGeoTagKeyName *keys, int n, int id)
return NULL;
}
static char *get_geokey_val(int key, int val)
static const char *get_geokey_val(int key, uint16_t val)
{
char *ap;
if (val == TIFF_GEO_KEY_UNDEFINED)
return av_strdup("undefined");
return "undefined";
if (val == TIFF_GEO_KEY_USER_DEFINED)
return av_strdup("User-Defined");
return "User-Defined";
#define RET_GEOKEY_VAL(TYPE, array)\
if (val >= TIFF_##TYPE##_OFFSET &&\
val - TIFF_##TYPE##_OFFSET < FF_ARRAY_ELEMS(tiff_##array##_codes))\
return av_strdup(tiff_##array##_codes[val - TIFF_##TYPE##_OFFSET]);
return tiff_##array##_codes[val - TIFF_##TYPE##_OFFSET];
switch (key) {
case TIFF_GT_MODEL_TYPE_GEOKEY:
@ -224,13 +223,9 @@ static char *get_geokey_val(int key, int val)
RET_GEOKEY_VAL(PRIME_MERIDIAN, prime_meridian);
break;
case TIFF_PROJECTED_CS_TYPE_GEOKEY:
ap = av_strdup(search_keyval(tiff_proj_cs_type_codes, FF_ARRAY_ELEMS(tiff_proj_cs_type_codes), val));
if(ap) return ap;
break;
return search_keyval(tiff_proj_cs_type_codes, FF_ARRAY_ELEMS(tiff_proj_cs_type_codes), val);
case TIFF_PROJECTION_GEOKEY:
ap = av_strdup(search_keyval(tiff_projection_codes, FF_ARRAY_ELEMS(tiff_projection_codes), val));
if(ap) return ap;
break;
return search_keyval(tiff_projection_codes, FF_ARRAY_ELEMS(tiff_projection_codes), val);
case TIFF_PROJ_COORD_TRANS_GEOKEY:
RET_GEOKEY_VAL(COORD_TRANS, coord_trans);
break;
@ -241,10 +236,7 @@ static char *get_geokey_val(int key, int val)
}
ap = av_malloc(14);
if (ap)
snprintf(ap, 14, "Unknown-%d", val);
return ap;
return NULL;
}
static char *doubles2str(double *dp, int count, const char *sep)
@ -1630,14 +1622,20 @@ static int tiff_decode_tag(TiffContext *s, AVFrame *frame)
goto end;
}
for (i = 0; i < s->geotag_count; i++) {
unsigned val;
s->geotags[i].key = ff_tget_short(&s->gb, s->le);
s->geotags[i].type = ff_tget_short(&s->gb, s->le);
s->geotags[i].count = ff_tget_short(&s->gb, s->le);
val = ff_tget_short(&s->gb, s->le);
if (!s->geotags[i].type)
s->geotags[i].val = get_geokey_val(s->geotags[i].key, ff_tget_short(&s->gb, s->le));
else
s->geotags[i].offset = ff_tget_short(&s->gb, s->le);
if (!s->geotags[i].type) {
const char *str = get_geokey_val(s->geotags[i].key, val);
s->geotags[i].val = str ? av_strdup(str) : av_asprintf("Unknown-%u", val);
if (!s->geotags[i].val)
return AVERROR(ENOMEM);
} else
s->geotags[i].offset = val;
}
break;
case TIFF_GEO_DOUBLE_PARAMS: