[dfont] Clean up sanitize()

I don't think I broke anything.  Fuzzers will let me know..
This commit is contained in:
Behdad Esfahbod 2018-09-13 16:49:26 +02:00
parent 361fc26861
commit dbb764dceb
2 changed files with 64 additions and 66 deletions

View File

@ -532,9 +532,17 @@ struct hb_bytes_t
inline hb_bytes_t (void) : bytes (nullptr), len (0) {}
inline hb_bytes_t (const char *bytes_, unsigned int len_) : bytes (bytes_), len (len_) {}
inline hb_bytes_t (const void *bytes_, unsigned int len_) : bytes ((const char *) bytes_), len (len_) {}
template <typename T>
inline hb_bytes_t (const T& array) : bytes ((const char *) array.arrayZ), len (array.len) {}
inline void free (void) { ::free ((void *) bytes); bytes = nullptr; len = 0; }
template <typename Type>
inline const Type* as (void) const
{
return unlikely (!bytes) ? &Null(Type) : reinterpret_cast<const Type *> (bytes);
}
inline int cmp (const hb_bytes_t &a) const
{
if (len != a.len)

View File

@ -293,18 +293,24 @@ struct TTCHeader
struct ResourceRecord
{
inline bool sanitize (hb_sanitize_context_t *c) const
inline const hb_bytes_t get_data (const void *data_base) const
{ return hb_bytes_t (data_base+offset); }
inline bool sanitize (hb_sanitize_context_t *c,
const void *data_base) const
{
TRACE_SANITIZE (this);
// actual data sanitization is done on ResourceForkHeader sanitizer
return_trace (likely (c->check_struct (this)));
return_trace (c->check_struct (this) &&
offset.sanitize (c, data_base));
}
protected:
HBUINT16 id; /* Resource ID, is really should be signed? */
HBINT16 nameOffset; /* Offset from beginning of resource name list
* to resource name, -1 means there is none. */
HBUINT8 attrs; /* Resource attributes */
HBUINT24 dataOffset; /* Offset from beginning of resource data to
OffsetTo<LArrayOf<HBUINT8>, HBUINT24>
offset; /* Offset from beginning of data block to
* data for this resource */
HBUINT32 reserved; /* Reserved for handle to resource */
public:
@ -313,28 +319,33 @@ struct ResourceRecord
struct ResourceTypeRecord
{
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
// RefList sanitization is done on ResourceMap sanitizer
return_trace (likely (c->check_struct (this)));
}
inline unsigned int get_resource_count () const { return resCountM1 + 1; }
inline bool is_sfnt () const { return tag == HB_TAG ('s','f','n','t'); }
inline const ResourceRecord& get_resource_record (const void *base,
unsigned int i) const
inline const ResourceRecord& get_resource_record (unsigned int i,
const void *type_base) const
{
return (base+refList)[i];
return hb_array_t<ResourceRecord> ((type_base+resourcesZ).arrayZ,
get_resource_count ()) [i];
}
inline bool sanitize (hb_sanitize_context_t *c,
const void *type_base,
const void *data_base) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
resourcesZ.sanitize (c, type_base,
get_resource_count (),
data_base));
}
protected:
Tag tag; /* Resource type. */
HBUINT16 resCountM1; /* Number of resources minus 1. */
OffsetTo<UnsizedArrayOf<ResourceRecord> >
refList; /* Offset from beginning of resource type list
resourcesZ; /* Offset from beginning of resource type list
* to reference item list for this type. */
public:
DEFINE_SIZE_STATIC (8);
@ -342,35 +353,30 @@ struct ResourceTypeRecord
struct ResourceMap
{
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!c->check_struct (this)))
return_trace (false);
for (unsigned int i = 0; i < get_types_count (); ++i)
{
const ResourceTypeRecord& type = get_type_record (i);
if (unlikely (!type.sanitize (c)))
return_trace (false);
for (unsigned int j = 0; j < type.get_resource_count (); ++j)
if (unlikely (!get_resource_record (type, j).sanitize (c)))
return_trace (false);
}
return_trace (true);
}
inline const ResourceTypeRecord& get_type_record (unsigned int i) const
{
// Why offset from the third byte of the object? I'm not sure
return (((const char *) this + 2)+typeListZ)[i];
return hb_array_t<ResourceTypeRecord> (((2 + (const char *) this )+typeListZ).arrayZ,
get_type_count ()) [i];
}
inline unsigned int get_types_count () const { return typeCountM1 + 1; }
inline unsigned int get_type_count () const { return typeCountM1 + 1; }
inline const ResourceRecord &get_resource_record (const ResourceTypeRecord &type,
unsigned int i) const
{
return type.get_resource_record (&(this+typeListZ), i);
return type.get_resource_record (i, &(this+typeListZ));
}
inline bool sanitize (hb_sanitize_context_t *c, const void *data_base) const
{
TRACE_SANITIZE (this);
const void *type_base = &(this+typeListZ);
return_trace (c->check_struct (this) &&
typeListZ.sanitize (c, 2 + (const char *) this,
get_type_count (),
type_base,
data_base));
}
protected:
@ -393,7 +399,8 @@ struct ResourceForkHeader
inline unsigned int get_face_count () const
{
const ResourceMap &resource_map = this+map;
for (unsigned int i = 0; i < resource_map.get_types_count (); ++i)
unsigned int count = resource_map.get_type_count ();
for (unsigned int i = 0; i < count; ++i)
{
const ResourceTypeRecord& type = resource_map.get_type_record (i);
if (type.is_sfnt ())
@ -402,23 +409,24 @@ struct ResourceForkHeader
return 0;
}
inline const LArrayOf<HBUINT8>& get_data (const ResourceTypeRecord& type,
unsigned int idx) const
inline const hb_bytes_t get_data (const ResourceTypeRecord& type,
unsigned int idx) const
{
const ResourceMap &resource_map = this+map;
unsigned int offset = dataOffset + resource_map.get_resource_record (type, idx).dataOffset;
return StructAtOffset<LArrayOf<HBUINT8> > (this, offset);
const void *data_base = &(this+data);
return resource_map.get_resource_record (type, idx).get_data (data_base);
}
inline const OpenTypeFontFace& get_face (unsigned int idx, unsigned int *base_offset = nullptr) const
inline const OpenTypeFontFace& get_face (unsigned int idx,
unsigned int *base_offset = nullptr) const
{
const ResourceMap &resource_map = this+map;
for (unsigned int i = 0; i < resource_map.get_types_count (); ++i)
for (unsigned int i = 0; i < resource_map.get_type_count (); ++i)
{
const ResourceTypeRecord& type = resource_map.get_type_record (i);
if (type.is_sfnt () && idx < type.get_resource_count ())
{
const OpenTypeFontFace &face = (OpenTypeFontFace&) get_data (type, idx).arrayZ;
const OpenTypeFontFace &face = *get_data (type, idx).as<OpenTypeFontFace> ();
if (base_offset)
*base_offset = (const char *) &face - (const char *) this;
return face;
@ -430,33 +438,15 @@ struct ResourceForkHeader
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!c->check_struct (this)))
return_trace (false);
return_trace (c->check_struct (this) &&
map.sanitize (c, this, &(this+data)));
const ResourceMap &resource_map = this+map;
if (unlikely (!resource_map.sanitize (c)))
return_trace (false);
for (unsigned int i = 0; i < resource_map.get_types_count (); ++i)
{
const ResourceTypeRecord& type = resource_map.get_type_record (i);
for (unsigned int j = 0; j < type.get_resource_count (); ++j)
{
const LArrayOf<HBUINT8>& data = get_data (type, j);
if (unlikely (!data.sanitize (c)))
return_trace (false);
if (unlikely (type.is_sfnt () &&
!((OpenTypeFontFace&) data.arrayZ).sanitize (c)))
return_trace (false);
}
}
return_trace (true);
// XXX Sanitize OpenTypeFontFace's
}
protected:
Offset32 dataOffset; /* Offset from beginning of resource fork
LOffsetTo<UnsizedArrayOf<HBUINT8> >
data; /* Offset from beginning of resource fork
* to resource data */
LOffsetTo<ResourceMap>
map; /* Offset from beginning of resource fork