ld: Handle extended-length data structures in PDB types
authorMark Harmstone <mark@harmstone.com>
Mon, 26 Dec 2022 20:47:49 +0000 (20:47 +0000)
committerAlan Modra <amodra@gmail.com>
Sat, 31 Dec 2022 08:56:23 +0000 (19:26 +1030)
A few fixes to minor issues I've discovered in my PDB patches.

* If sizes or offsets are greater than 0x8000, they get encoded as
extended values in the same way as for enum values - e.g. a LF_ULONG
.short followed by a .long.

* I've managed to coax MSVC to produce another type, LF_VFTABLE, which
is seen when dealing with COM. I don't think LLVM emits this. Note that
we can't just implement everything in Microsoft's header files, as most
of it is obsolete.

* Fixes a stupid bug in the test program, where I was adding an index to
a size. The index was hard-coded to 0, so this didn't cause any actual
issues.

ld/pdb.c
ld/pdb.h
ld/testsuite/ld-pe/pdb-types1-hashlist.d
ld/testsuite/ld-pe/pdb-types1-typelist.d
ld/testsuite/ld-pe/pdb-types1b.s
ld/testsuite/ld-pe/pdb.exp

index 6a5f737dcd4c97095d00ea6b63886798c0ee6c6b..60e9980407cc9127b19d1e50203ef5f732596554 100644 (file)
--- a/ld/pdb.c
+++ b/ld/pdb.c
@@ -2476,6 +2476,7 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
              case LF_MEMBER:
                {
                  struct lf_member *mem = (struct lf_member *) ptr;
+                 uint16_t offset;
                  size_t name_len, subtype_len;
 
                  if (left < offsetof (struct lf_member, name))
@@ -2488,9 +2489,34 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
                  if (!remap_type (&mem->type, map, type_num, num_types))
                    return false;
 
+                 subtype_len = offsetof (struct lf_member, name);
+
+                 offset = bfd_getl16 (&mem->offset);
+
+                 /* If offset >= 0x8000, actual value follows.  */
+                 if (offset >= 0x8000)
+                   {
+                     unsigned int param_len = extended_value_len (offset);
+
+                     if (param_len == 0)
+                       {
+                         einfo (_("%P: warning: unhandled type %v within"
+                                  " LF_MEMBER\n"), offset);
+                         return false;
+                       }
+
+                     subtype_len += param_len;
+
+                     if (left < subtype_len)
+                       {
+                         einfo (_("%P: warning: truncated CodeView type record"
+                                 " LF_MEMBER\n"));
+                         return false;
+                       }
+                   }
+
                  name_len =
-                   strnlen (mem->name,
-                            left - offsetof (struct lf_member, name));
+                   strnlen ((char *) mem + subtype_len, left - subtype_len);
 
                  if (name_len == left - offsetof (struct lf_member, name))
                    {
@@ -2501,7 +2527,7 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
 
                  name_len++;
 
-                 subtype_len = offsetof (struct lf_member, name) + name_len;
+                 subtype_len += name_len;
 
                  if (subtype_len % 4 != 0)
                    subtype_len += 4 - (subtype_len % 4);
@@ -2706,6 +2732,8 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
              case LF_BCLASS:
                {
                  struct lf_bclass *bc = (struct lf_bclass *) ptr;
+                 size_t subtype_len;
+                 uint16_t offset;
 
                  if (left < sizeof (struct lf_bclass))
                    {
@@ -2718,8 +2746,44 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
                                   num_types))
                    return false;
 
-                 ptr += sizeof (struct lf_bclass);
-                 left -= sizeof (struct lf_bclass);
+                 subtype_len = sizeof (struct lf_bclass);
+
+                 offset = bfd_getl16 (&bc->offset);
+
+                 /* If offset >= 0x8000, actual value follows.  */
+                 if (offset >= 0x8000)
+                   {
+                     unsigned int param_len = extended_value_len (offset);
+
+                     if (param_len == 0)
+                       {
+                         einfo (_("%P: warning: unhandled type %v within"
+                                  " LF_BCLASS\n"), offset);
+                         return false;
+                       }
+
+                     subtype_len += param_len;
+
+                     if (left < subtype_len)
+                       {
+                         einfo (_("%P: warning: truncated CodeView type record"
+                                  " LF_BCLASS\n"));
+                         return false;
+                       }
+                   }
+
+                 if (subtype_len % 4 != 0)
+                   subtype_len += 4 - (subtype_len % 4);
+
+                 if (left < subtype_len)
+                   {
+                     einfo (_("%P: warning: truncated CodeView type record"
+                              " LF_BCLASS\n"));
+                     return false;
+                   }
+
+                 ptr += subtype_len;
+                 left -= subtype_len;
 
                  break;
                }
@@ -2748,6 +2812,8 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
              case LF_IVBCLASS:
                {
                  struct lf_vbclass *vbc = (struct lf_vbclass *) ptr;
+                 size_t subtype_len;
+                 uint16_t offset;
 
                  if (left < sizeof (struct lf_vbclass))
                    {
@@ -2764,8 +2830,70 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
                                   type_num, num_types))
                    return false;
 
-                 ptr += sizeof (struct lf_vbclass);
-                 left -= sizeof (struct lf_vbclass);
+                 subtype_len = offsetof (struct lf_vbclass,
+                                         virtual_base_vbtable_offset);
+
+                 offset = bfd_getl16 (&vbc->virtual_base_pointer_offset);
+
+                 /* If offset >= 0x8000, actual value follows.  */
+                 if (offset >= 0x8000)
+                   {
+                     unsigned int param_len = extended_value_len (offset);
+
+                     if (param_len == 0)
+                       {
+                         einfo (_("%P: warning: unhandled type %v within"
+                                  " LF_VBCLASS/LF_IVBCLASS\n"), offset);
+                         return false;
+                       }
+
+                     subtype_len += param_len;
+
+                     if (left < subtype_len)
+                       {
+                         einfo (_("%P: warning: truncated CodeView type record"
+                                  " LF_VBCLASS/LF_IVBCLASS\n"));
+                         return false;
+                       }
+                   }
+
+                 offset = bfd_getl16 ((char *)vbc + subtype_len);
+                 subtype_len += sizeof (uint16_t);
+
+                 /* If offset >= 0x8000, actual value follows.  */
+                 if (offset >= 0x8000)
+                   {
+                     unsigned int param_len = extended_value_len (offset);
+
+                     if (param_len == 0)
+                       {
+                         einfo (_("%P: warning: unhandled type %v within"
+                                  " LF_VBCLASS/LF_IVBCLASS\n"), offset);
+                         return false;
+                       }
+
+                     subtype_len += param_len;
+
+                     if (left < subtype_len)
+                       {
+                         einfo (_("%P: warning: truncated CodeView type record"
+                                  " LF_VBCLASS/LF_IVBCLASS\n"));
+                         return false;
+                       }
+                   }
+
+                 if (subtype_len % 4 != 0)
+                   subtype_len += 4 - (subtype_len % 4);
+
+                 if (left < subtype_len)
+                   {
+                     einfo (_("%P: warning: truncated CodeView type record"
+                              " LF_VBCLASS/LF_IVBCLASS\n"));
+                     return false;
+                   }
+
+                 ptr += subtype_len;
+                 left -= subtype_len;
 
                  break;
                }
@@ -2950,8 +3078,8 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
     case LF_STRUCTURE:
       {
        struct lf_class *cl = (struct lf_class *) data;
-       uint16_t prop;
-       size_t name_len;
+       uint16_t prop, num_bytes;
+       size_t name_len, name_off;
 
        if (size < offsetof (struct lf_class, name))
          {
@@ -2969,9 +3097,35 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
        if (!remap_type (&cl->vshape, map, type_num, num_types))
          return false;
 
-       name_len = strnlen (cl->name, size - offsetof (struct lf_class, name));
+       name_off = offsetof (struct lf_class, name);
+
+       num_bytes = bfd_getl16 (&cl->length);
 
-       if (name_len == size - offsetof (struct lf_class, name))
+       /* If num_bytes >= 0x8000, actual value follows.  */
+       if (num_bytes >= 0x8000)
+         {
+           unsigned int param_len = extended_value_len (num_bytes);
+
+           if (param_len == 0)
+             {
+               einfo (_("%P: warning: unhandled type %v within"
+                        " LF_CLASS/LF_STRUCTURE\n"), num_bytes);
+               return false;
+             }
+
+           name_off += param_len;
+
+           if (size < name_off)
+             {
+               einfo (_("%P: warning: truncated CodeView type record"
+                        " LF_CLASS/LF_STRUCTURE\n"));
+               return false;
+             }
+         }
+
+       name_len = strnlen ((char *) cl + name_off, size - name_off);
+
+       if (name_len == size - name_off)
          {
            einfo (_("%P: warning: name for LF_CLASS/LF_STRUCTURE has no"
                     " terminating zero\n"));
@@ -2984,10 +3138,11 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
          {
            /* Structure has another name following first one.  */
 
-           size_t len = offsetof (struct lf_class, name) + name_len + 1;
+           size_t len = name_off + name_len + 1;
            size_t unique_name_len;
 
-           unique_name_len = strnlen (cl->name + name_len + 1, size - len);
+           unique_name_len = strnlen ((char *) cl + name_off + name_len + 1,
+                                      size - len);
 
            if (unique_name_len == size - len)
              {
@@ -2998,10 +3153,10 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
          }
 
        if (!(prop & (CV_PROP_FORWARD_REF | CV_PROP_SCOPED))
-           && !is_name_anonymous (cl->name, name_len))
+           && !is_name_anonymous ((char *) cl + name_off, name_len))
          {
            other_hash = true;
-           cv_hash = crc32 ((uint8_t *) cl->name, name_len);
+           cv_hash = crc32 ((uint8_t *) cl + name_off, name_len);
          }
 
        break;
@@ -3010,8 +3165,8 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
     case LF_UNION:
       {
        struct lf_union *un = (struct lf_union *) data;
-       uint16_t prop;
-       size_t name_len;
+       uint16_t prop, num_bytes;
+       size_t name_len, name_off;
 
        if (size < offsetof (struct lf_union, name))
          {
@@ -3023,9 +3178,35 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
        if (!remap_type (&un->field_list, map, type_num, num_types))
          return false;
 
-       name_len = strnlen (un->name, size - offsetof (struct lf_union, name));
+       name_off = offsetof (struct lf_union, name);
+
+       num_bytes = bfd_getl16 (&un->length);
+
+       /* If num_bytes >= 0x8000, actual value follows.  */
+       if (num_bytes >= 0x8000)
+         {
+           unsigned int param_len = extended_value_len (num_bytes);
+
+           if (param_len == 0)
+             {
+               einfo (_("%P: warning: unhandled type %v within"
+                        " LF_UNION\n"), num_bytes);
+               return false;
+             }
+
+           name_off += param_len;
+
+           if (size < name_off)
+             {
+               einfo (_("%P: warning: truncated CodeView type record"
+                        " LF_UNION\n"));
+               return false;
+             }
+         }
+
+       name_len = strnlen ((char *) un + name_off, size - name_off);
 
-       if (name_len == size - offsetof (struct lf_union, name))
+       if (name_len == size - name_off)
          {
            einfo (_("%P: warning: name for LF_UNION has no"
                     " terminating zero\n"));
@@ -3038,10 +3219,11 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
          {
            /* Structure has another name following first one.  */
 
-           size_t len = offsetof (struct lf_union, name) + name_len + 1;
+           size_t len = name_off + name_len + 1;
            size_t unique_name_len;
 
-           unique_name_len = strnlen (un->name + name_len + 1, size - len);
+           unique_name_len = strnlen ((char *) un + name_off + name_len + 1,
+                                      size - len);
 
            if (unique_name_len == size - len)
              {
@@ -3052,10 +3234,10 @@ handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
          }
 
        if (!(prop & (CV_PROP_FORWARD_REF | CV_PROP_SCOPED))
-           && !is_name_anonymous (un->name, name_len))
+           && !is_name_anonymous ((char *) un + name_off, name_len))
          {
            other_hash = true;
-           cv_hash = crc32 ((uint8_t *) un->name, name_len);
+           cv_hash = crc32 ((uint8_t *) un + name_off, name_len);
          }
 
        break;
index 749a60249df32bc6f4ce440f87e01b8b159a1448..ddf731b99c9ef50694321b1544a027c38ec46187 100644 (file)
--- a/ld/pdb.h
+++ b/ld/pdb.h
@@ -480,7 +480,6 @@ struct lf_bclass
   uint16_t attributes;
   uint32_t base_class_type;
   uint16_t offset;
-  uint16_t padding;
 } ATTRIBUTE_PACKED;
 
 /* lfVFuncTab in cvinfo.h */
index b75f08c1de754be557cc45778b4da895441579a3..aa00aaf75933dac9df132afa8ecb408ba0cfa5b0 100644 (file)
@@ -10,4 +10,6 @@ Contents of section .data:
  0050 ffd80200 b0260100 7c060200 e3240200  *
  0060 63ff0100 fb6b0300 0ad90100 523c0200  *
  0070 4d5e0200 8a940200 4b710300 6aa90300  *
- 0080 0a2c0300 67e10300 4a3d0300           *
\ No newline at end of file
+ 0080 0a2c0300 67e10300 4a3d0300 fa460300  *
+ 0090 db020200 ec4e0100 131e0300 fb120300  *
+ 00a0 aece0200 1db70100                    *
\ No newline at end of file
index ff2d91c311ea0eefd56cc62c014cdb8de0685780..df862c3f8376713c1627af9f9611fa364fbbc886 100644 (file)
@@ -57,4 +57,18 @@ Contents of section .data:
  0340 7200f2f1 10150000 20100000 6e657374  r....... ...nest
  0350 65645f65 6e756d00 1a000515 01000000  ed_enum.........
  0360 21100000 00000000 00000000 04007175  !.............qu
- 0370 757800f1                             ux..            
\ No newline at end of file
+ 0370 757800f1 12000315 10000000 74000000  ux..........t...
+ 0380 028060ea 00f3f2f1 2e000312 0d150300  ..`.............
+ 0390 23100000 00006100 0d150300 23100000  #.....a.....#...
+ 03a0 028060ea 6200f2f1 0d150300 23100000  ..`.b.......#...
+ 03b0 0480c0d4 01006300 26000515 03000000  ......c.&.......
+ 03c0 24100000 00000000 00000000 048020bf  $............. .
+ 03d0 02006c6f 6e677374 72756374 00f3f2f1  ..longstruct....
+ 03e0 1a000312 0d150300 23100000 00006100  ........#.....a.
+ 03f0 0d150300 23100000 00006200 1a000615  ....#.....b.....
+ 0400 02000000 26100000 028060ea 6c6f6e67  ....&.....`.long
+ 0410 756e696f 6e00f2f1 1e000312 00140000  union...........
+ 0420 25100000 0480c0d4 0100f2f1 0d150300  %...............
+ 0430 23100000 00006400 26000312 01140000  #.....d.&.......
+ 0440 25100000 00000000 028060ea 0480c0d4  %.........`.....
+ 0450 0100f2f1 0d150300 23100000 00006400  ........#.....d.
\ No newline at end of file
index 89ee6e3840fb08bb5def2ec35f6b29a608d4fd72..544b338c251d2fa7127014961769ca41534db544 100644 (file)
@@ -33,6 +33,7 @@
 
 .equ LF_USHORT, 0x8002
 .equ LF_LONG, 0x8003
+.equ LF_ULONG, 0x8004
 .equ LF_UQUADWORD, 0x800a
 
 .equ CV_PTR_NEAR32, 0xa
 
 # Type 1021, struct quux, field list 1020
 .struct4:
-.short .types_end - .struct4 - 2
+.short .arr2 - .struct4 - 2
 .short LF_STRUCTURE
 .short 1 # no. members
 .short 0 # property
 .asciz "quux" # name
 .byte 0xf1 # padding
 
+# Type 1022, array[60000] of char
+.arr2:
+.short .fieldlist8 - .arr2 - 2
+.short LF_ARRAY
+.long T_CHAR # element type
+.long T_INT4 # index type
+.short LF_USHORT
+.short 60000 # size in bytes
+.byte 0 # name
+.byte 0xf3 # padding
+.byte 0xf2 # padding
+.byte 0xf1 # padding
+
+# Type 1023, field list for struct longstruct
+.fieldlist8:
+.short .struct5 - .fieldlist8 - 2
+.short LF_FIELDLIST
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short 0 # offset
+.asciz "a"
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short LF_USHORT
+.short 60000 # offset
+.asciz "b"
+.byte 0xf2 # padding
+.byte 0xf1 # padding
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short LF_ULONG
+.long 120000 # offset
+.asciz "c"
+
+# Type 1024, struct longstruct
+.struct5:
+.short .fieldlist9 - .struct5 - 2
+.short LF_STRUCTURE
+.short 3 # no. members
+.short 0 # property
+.long 0x1023 # field list
+.long 0 # type derived from
+.long 0 # type of vshape table
+.short LF_ULONG
+.long 180000 # size
+.asciz "longstruct" # name
+.byte 0xf3 # padding
+.byte 0xf2 # padding
+.byte 0xf1 # padding
+
+# Type 1025, field list for union longunion
+.fieldlist9:
+.short .union4 - .fieldlist9 - 2
+.short LF_FIELDLIST
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short 0 # offset
+.asciz "a"
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short 0 # offset
+.asciz "b"
+
+# Type 1026, union longunion (field list 1025)
+.union4:
+.short .fieldlist10 - .union4 - 2
+.short LF_UNION
+.short 2 # no. members
+.short 0 # property
+.long 0x1025 # field list
+.short LF_USHORT
+.short 60000 # size
+.asciz "longunion"
+.byte 0xf2 # padding
+.byte 0xf1 # padding
+
+# Type 1027, field list with base class longstruct
+.fieldlist10:
+.short .fieldlist11 - .fieldlist10 - 2
+.short LF_FIELDLIST
+.short LF_BCLASS
+.short 0 # attributes
+.long 0x1024 # base class
+.short LF_ULONG
+.long 120000 # offset within class
+.byte 0xf2 # padding
+.byte 0xf1 # padding
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short 0 # offset
+.asciz "d"
+
+# Type 1028, field list with virtual base class longstruct
+.fieldlist11:
+.short .types_end - .fieldlist11 - 2
+.short LF_FIELDLIST
+.short LF_VBCLASS
+.short 0 # attributes
+.long 0x1024 # type index of direct virtual base class
+.long 0 # type index of virtual base pointer
+.short LF_USHORT
+.short 60000 # virtual base pointer offset
+.short LF_ULONG
+.long 120000 # virtual base offset from vbtable
+.byte 0xf2 # padding
+.byte 0xf1 # padding
+.short LF_MEMBER
+.short 3 # public
+.long 0x1022
+.short 0 # offset
+.asciz "d"
+
 .types_end:
index bd50b2fb076c79902f55c314b1f231f321dd09b2..fbc0cf949f193fc6342b33083d68437c92724733 100644 (file)
@@ -1029,7 +1029,7 @@ proc test5 { } {
     binary scan $data i end_type
 
     # end_type is one greater than the last type in the stream
-    if { $end_type != 0x1023 } {
+    if { $end_type != 0x102a } {
        fail "Incorrect end type value in TPI stream."
     } else {
        pass "Correct end type value in TPI stream."