* [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal
@ 2023-08-30 19:13 Tom de Vries
2023-08-30 19:13 ` [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields} Tom de Vries
` (5 more replies)
0 siblings, 6 replies; 14+ messages in thread
From: Tom de Vries @ 2023-08-30 19:13 UTC (permalink / raw)
To: gdb-patches
When running test-case gdb.dwarf2/per-bfd-sharing.exp with target board stabs,
gdb either segfaults or asserts due to reading uninitialized memory, allocated
here in buildsym_compunit::finish_block_internal:
...
ftype->set_fields
((struct field *)
TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
...
Fix this by using TYPE_ZALLOC instead.
Tested on x86_64-linux.
PR symtab/30810
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30810
---
gdb/buildsym.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gdb/buildsym.c b/gdb/buildsym.c
index 832b689cf03..65ce3a0f5a8 100644
--- a/gdb/buildsym.c
+++ b/gdb/buildsym.c
@@ -267,7 +267,7 @@ buildsym_compunit::finish_block_internal
ftype->set_num_fields (nparams);
ftype->set_fields
((struct field *)
- TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
+ TYPE_ZALLOC (ftype, nparams * sizeof (struct field)));
iparams = 0;
/* Here we want to directly access the dictionary, because
base-commit: 59487af3c8490bc5961d330bc0ef4d5f05ecdc59
--
2.35.3
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields}
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
@ 2023-08-30 19:13 ` Tom de Vries
2023-08-30 20:17 ` Tom Tromey
2023-08-30 19:13 ` [PATCH 3/6] [gdb/symtab] Do more zero-initialization of type::fields Tom de Vries
` (4 subsequent siblings)
5 siblings, 1 reply; 14+ messages in thread
From: Tom de Vries @ 2023-08-30 19:13 UTC (permalink / raw)
To: gdb-patches
After finding this code in buildsym_compunit::finish_block_internal:
...
ftype->set_fields
((struct field *)
TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
...
and fixing PR30810 by using TYPE_ZALLOC, I wondered if there were more
locations that needed fixing.
I decided to make things easier to spot by factoring out a new function
alloc_fields:
...
/* Allocate the fields array of this type, with NFIELDS elements. If INIT,
zero-initialize the allocated memory. */
void alloc_fields (unsigned int nfields, bool init = true);
...
where:
- a regular use would be "alloc_fields (nfields)", and
- an exceptional use that needed no initialization would be
"alloc_fields (nfields, false)".
Pretty soon I discovered that most of the latter cases are due to
initialization by memcpy, so I added two variants of copy_fields as well.
After this rewrite there are 8 uses of set_fields left:
...
gdb/coffread.c: type->set_fields (nullptr);
gdb/coffread.c: type->set_fields (nullptr);
gdb/coffread.c: type->set_fields (nullptr);
gdb/eval.c: type->set_fields
gdb/gdbtypes.c: type->set_fields (args);
gdb/gdbtypes.c: t->set_fields (XRESIZEVEC (struct field, t->fields (),
gdb/dwarf2/read.c: type->set_fields (new_fields);
gdb/dwarf2/read.c: sub_type->set_fields (sub_type->fields () + 1);
...
These fall into the following categories:
- set to nullptr (coffread.c),
- type not owned by objfile or gdbarch (eval.c), and
- modifying an existing fields array, like adding an element at the end or
dropping an element at the start (the rest).
Tested on x86_64-linux.
---
gdb/ada-lang.c | 19 ++------
gdb/amdgpu-tdep.c | 5 +--
gdb/buildsym.c | 5 +--
gdb/coffread.c | 15 ++-----
gdb/ctfread.c | 7 +--
gdb/dwarf2/read.c | 40 +++--------------
gdb/gdbtypes.c | 88 ++++++++++++++++++++++---------------
gdb/gdbtypes.h | 8 ++++
gdb/gnu-v3-abi.c | 106 ++++++++++++++++++++++++---------------------
gdb/mdebugread.c | 9 +---
gdb/rust-lang.c | 4 +-
gdb/stabsread.c | 21 ++-------
gdb/windows-tdep.c | 4 +-
13 files changed, 141 insertions(+), 190 deletions(-)
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 575568cffb5..5b856da3189 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -7772,9 +7772,7 @@ ada_template_to_fixed_record_type_1 (struct type *type,
rtype = type_allocator (type).new_type ();
rtype->set_code (TYPE_CODE_STRUCT);
INIT_NONE_SPECIFIC (rtype);
- rtype->set_num_fields (nfields);
- rtype->set_fields
- ((struct field *) TYPE_ZALLOC (rtype, nfields * sizeof (struct field)));
+ rtype->alloc_fields (nfields);
rtype->set_name (ada_type_name (type));
rtype->set_is_fixed_instance (true);
@@ -8024,14 +8022,8 @@ template_to_static_fixed_type (struct type *type0)
type0->set_target_type (type);
type->set_code (type0->code ());
INIT_NONE_SPECIFIC (type);
- type->set_num_fields (nfields);
- field *fields =
- ((struct field *)
- TYPE_ALLOC (type, nfields * sizeof (struct field)));
- memcpy (fields, type0->fields (),
- sizeof (struct field) * nfields);
- type->set_fields (fields);
+ type->copy_fields (type0);
type->set_name (ada_type_name (type0));
type->set_is_fixed_instance (true);
@@ -8077,12 +8069,7 @@ to_record_with_fixed_variant_part (struct type *type, const gdb_byte *valaddr,
rtype = type_allocator (type).new_type ();
rtype->set_code (TYPE_CODE_STRUCT);
INIT_NONE_SPECIFIC (rtype);
- rtype->set_num_fields (nfields);
-
- field *fields =
- (struct field *) TYPE_ALLOC (rtype, nfields * sizeof (struct field));
- memcpy (fields, type->fields (), sizeof (struct field) * nfields);
- rtype->set_fields (fields);
+ rtype->copy_fields (type);
rtype->set_name (ada_type_name (type));
rtype->set_is_fixed_instance (true);
diff --git a/gdb/amdgpu-tdep.c b/gdb/amdgpu-tdep.c
index 21a7a3ae1b7..3a521a43977 100644
--- a/gdb/amdgpu-tdep.c
+++ b/gdb/amdgpu-tdep.c
@@ -757,10 +757,7 @@ amd_dbgapi_register_type_to_gdb_type (const amd_dbgapi_register_type &type,
.new_type (TYPE_CODE_ENUM, enum_type.bit_size (),
enum_type.name ().c_str ()));
- gdb_type->set_num_fields (enum_type.size ());
- gdb_type->set_fields
- ((struct field *) TYPE_ZALLOC (gdb_type, (sizeof (struct field)
- * enum_type.size ())));
+ gdb_type->alloc_fields (enum_type.size ());
gdb_type->set_is_unsigned (true);
for (size_t i = 0; i < enum_type.size (); ++i)
diff --git a/gdb/buildsym.c b/gdb/buildsym.c
index 65ce3a0f5a8..3c1e9179411 100644
--- a/gdb/buildsym.c
+++ b/gdb/buildsym.c
@@ -264,10 +264,7 @@ buildsym_compunit::finish_block_internal
}
if (nparams > 0)
{
- ftype->set_num_fields (nparams);
- ftype->set_fields
- ((struct field *)
- TYPE_ZALLOC (ftype, nparams * sizeof (struct field)));
+ ftype->alloc_fields (nparams);
iparams = 0;
/* Here we want to directly access the dictionary, because
diff --git a/gdb/coffread.c b/gdb/coffread.c
index c2fe9fa1761..e132dd1a1f7 100644
--- a/gdb/coffread.c
+++ b/gdb/coffread.c
@@ -1462,14 +1462,9 @@ patch_type (struct type *type, struct type *real_type)
{
struct type *target = type->target_type ();
struct type *real_target = real_type->target_type ();
- int field_size = real_target->num_fields () * sizeof (struct field);
target->set_length (real_target->length ());
- target->set_num_fields (real_target->num_fields ());
-
- field *fields = (struct field *) TYPE_ALLOC (target, field_size);
- memcpy (fields, real_target->fields (), field_size);
- target->set_fields (fields);
+ target->copy_fields (real_target);
if (real_target->name ())
{
@@ -2037,9 +2032,7 @@ coff_read_struct_type (int index, int length, int lastsym,
}
/* Now create the vector of fields, and record how big it is. */
- type->set_num_fields (nfields);
- type->set_fields
- ((struct field *) TYPE_ALLOC (type, sizeof (struct field) * nfields));
+ type->alloc_fields (nfields, false);
/* Copy the saved-up fields into the field vector. */
@@ -2117,9 +2110,7 @@ coff_read_enum_type (int index, int length, int lastsym,
else /* Assume ints. */
type->set_length (gdbarch_int_bit (gdbarch) / TARGET_CHAR_BIT);
type->set_code (TYPE_CODE_ENUM);
- type->set_num_fields (nsyms);
- type->set_fields
- ((struct field *) TYPE_ALLOC (type, sizeof (struct field) * nsyms));
+ type->alloc_fields (nsyms, false);
/* Find the symbols for the values and put them into the type.
The symbols can be found in the symlist that we put them on
diff --git a/gdb/ctfread.c b/gdb/ctfread.c
index 16292c74b1a..859908923a4 100644
--- a/gdb/ctfread.c
+++ b/gdb/ctfread.c
@@ -346,9 +346,7 @@ attach_fields_to_type (struct ctf_field_info *fip, struct type *type)
return;
/* Record the field count, allocate space for the array of fields. */
- type->set_num_fields (nfields);
- type->set_fields
- ((struct field *) TYPE_ZALLOC (type, sizeof (struct field) * nfields));
+ type->alloc_fields (nfields);
/* Copy the saved-up fields into the field vector. */
for (int i = 0; i < nfields; ++i)
@@ -715,8 +713,7 @@ read_func_kind_type (struct ctf_context *ccp, ctf_id_t tid)
if (ctf_func_type_args (fp, tid, argc, argv.data ()) == CTF_ERR)
return nullptr;
- type->set_fields
- ((struct field *) TYPE_ZALLOC (type, argc * sizeof (struct field)));
+ type->alloc_fields (argc);
struct type *void_type = builtin_type (of)->builtin_void;
/* If failed to find the argument type, fill it with void_type. */
for (int iparam = 0; iparam < argc; iparam++)
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 5b32089094d..7fe0e84cdda 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -6054,11 +6054,9 @@ quirk_rust_enum (struct type *type, struct objfile *objfile)
/* Smash this type to be a structure type. We have to do this
because the type has already been recorded. */
type->set_code (TYPE_CODE_STRUCT);
- type->set_num_fields (3);
/* Save the field we care about. */
struct field saved_field = type->field (0);
- type->set_fields
- ((struct field *) TYPE_ZALLOC (type, 3 * sizeof (struct field)));
+ type->alloc_fields (3);
/* Put the discriminant at index 0. */
type->field (0).set_type (field_type);
@@ -12059,9 +12057,7 @@ dwarf2_attach_fields_to_type (struct field_info *fip, struct type *type,
/* Record the field count, allocate space for the array of fields,
and create blank accessibility bitfields if necessary. */
- type->set_num_fields (nfields);
- type->set_fields
- ((struct field *) TYPE_ZALLOC (type, sizeof (struct field) * nfields));
+ type->alloc_fields (nfields);
if (fip->non_public_fields && cu->lang () != language_ada)
{
@@ -12490,12 +12486,7 @@ rewrite_array_type (struct type *type)
updated. Either way we want to copy the type and update
everything. */
struct type *copy = copy_type (type);
- int nfields = copy->num_fields ();
- field *new_fields
- = ((struct field *) TYPE_ZALLOC (copy,
- nfields * sizeof (struct field)));
- memcpy (new_fields, copy->fields (), nfields * sizeof (struct field));
- copy->set_fields (new_fields);
+ copy->copy_fields (type);
if (new_target != nullptr)
copy->set_target_type (new_target);
@@ -13260,14 +13251,7 @@ update_enumeration_type_from_children (struct die_info *die,
}
if (!fields.empty ())
- {
- type->set_num_fields (fields.size ());
- type->set_fields
- ((struct field *)
- TYPE_ALLOC (type, sizeof (struct field) * fields.size ()));
- memcpy (type->fields (), fields.data (),
- sizeof (struct field) * fields.size ());
- }
+ type->copy_fields (fields);
else
flag_enum = 0;
@@ -13636,12 +13620,7 @@ quirk_ada_thick_pointer (struct die_info *die, struct dwarf2_cu *cu,
struct type *bounds = alloc.new_type ();
bounds->set_code (TYPE_CODE_STRUCT);
- bounds->set_num_fields (range_fields.size ());
- bounds->set_fields
- ((struct field *) TYPE_ALLOC (bounds, (bounds->num_fields ()
- * sizeof (struct field))));
- memcpy (bounds->fields (), range_fields.data (),
- bounds->num_fields () * sizeof (struct field));
+ bounds->copy_fields (range_fields);
int last_fieldno = range_fields.size () - 1;
int bounds_size = (bounds->field (last_fieldno).loc_bitpos () / 8
@@ -13664,10 +13643,7 @@ quirk_ada_thick_pointer (struct die_info *die, struct dwarf2_cu *cu,
struct type *result = type_allocator (objfile).new_type ();
result->set_code (TYPE_CODE_STRUCT);
- result->set_num_fields (2);
- result->set_fields
- ((struct field *) TYPE_ZALLOC (result, (result->num_fields ()
- * sizeof (struct field))));
+ result->alloc_fields (2);
/* The names are chosen to coincide with what the compiler does with
-fgnat-encodings=all, which the Ada code in gdb already
@@ -14709,9 +14685,7 @@ read_subroutine_type (struct die_info *die, struct dwarf2_cu *cu)
}
/* Allocate storage for parameters and fill them in. */
- ftype->set_num_fields (nparams);
- ftype->set_fields
- ((struct field *) TYPE_ZALLOC (ftype, nparams * sizeof (struct field)));
+ ftype->alloc_fields (nparams);
/* TYPE_FIELD_TYPE must never be NULL. Pre-fill the array to ensure it
even if we error out during the parameters reading below. */
diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c
index 939fcc23b82..766107a7013 100644
--- a/gdb/gdbtypes.c
+++ b/gdb/gdbtypes.c
@@ -597,9 +597,7 @@ lookup_function_type_with_arguments (struct type *type,
fn->set_is_prototyped (true);
}
- fn->set_num_fields (nparams);
- fn->set_fields
- ((struct field *) TYPE_ZALLOC (fn, nparams * sizeof (struct field)));
+ fn->alloc_fields (nparams);
for (i = 0; i < nparams; ++i)
fn->field (i).set_type (param_types[i]);
@@ -1356,9 +1354,7 @@ create_array_type_with_stride (type_allocator &alloc,
result_type->set_code (TYPE_CODE_ARRAY);
result_type->set_target_type (element_type);
- result_type->set_num_fields (1);
- result_type->set_fields
- ((struct field *) TYPE_ZALLOC (result_type, sizeof (struct field)));
+ result_type->alloc_fields (1);
result_type->set_index_type (range_type);
if (byte_stride_prop != NULL)
result_type->add_dyn_prop (DYN_PROP_BYTE_STRIDE, *byte_stride_prop);
@@ -1442,9 +1438,7 @@ create_set_type (type_allocator &alloc, struct type *domain_type)
struct type *result_type = alloc.new_type ();
result_type->set_code (TYPE_CODE_SET);
- result_type->set_num_fields (1);
- result_type->set_fields
- ((struct field *) TYPE_ZALLOC (result_type, sizeof (struct field)));
+ result_type->alloc_fields (1);
if (!domain_type->is_stub ())
{
@@ -2452,13 +2446,7 @@ resolve_dynamic_union (struct type *type,
gdb_assert (type->code () == TYPE_CODE_UNION);
resolved_type = copy_type (type);
- resolved_type->set_fields
- ((struct field *)
- TYPE_ALLOC (resolved_type,
- resolved_type->num_fields () * sizeof (struct field)));
- memcpy (resolved_type->fields (),
- type->fields (),
- resolved_type->num_fields () * sizeof (struct field));
+ resolved_type->copy_fields (type);
for (i = 0; i < resolved_type->num_fields (); ++i)
{
struct type *t;
@@ -2618,12 +2606,10 @@ compute_variant_fields (struct type *type,
for (const auto &part : parts)
compute_variant_fields_inner (type, addr_stack, part, flags);
- resolved_type->set_num_fields
- (std::count (flags.begin (), flags.end (), true));
- resolved_type->set_fields
- ((struct field *)
- TYPE_ALLOC (resolved_type,
- resolved_type->num_fields () * sizeof (struct field)));
+ unsigned int nfields = std::count (flags.begin (), flags.end (), true);
+ /* No need to zero-initialize the newly allocated fields, they'll be
+ initialized by the copy in the loop below. */
+ resolved_type->alloc_fields (nfields, false);
int out = 0;
for (int i = 0; i < type->num_fields (); ++i)
@@ -2664,14 +2650,7 @@ resolve_dynamic_struct (struct type *type,
}
else
{
- resolved_type->set_fields
- ((struct field *)
- TYPE_ALLOC (resolved_type,
- resolved_type->num_fields () * sizeof (struct field)));
- if (type->num_fields () > 0)
- memcpy (resolved_type->fields (),
- type->fields (),
- resolved_type->num_fields () * sizeof (struct field));
+ resolved_type->copy_fields (type);
}
for (i = 0; i < resolved_type->num_fields (); ++i)
@@ -5556,9 +5535,7 @@ copy_type_recursive (struct type *type, htab_t copied_types)
int i, nfields;
nfields = type->num_fields ();
- new_type->set_fields
- ((struct field *)
- TYPE_ZALLOC (new_type, nfields * sizeof (struct field)));
+ new_type->alloc_fields (type->num_fields ());
for (i = 0; i < nfields; i++)
{
@@ -5703,10 +5680,9 @@ arch_flags_type (struct gdbarch *gdbarch, const char *name, int bit)
type = type_allocator (gdbarch).new_type (TYPE_CODE_FLAGS, bit, name);
type->set_is_unsigned (true);
- type->set_num_fields (0);
/* Pre-allocate enough space assuming every field is one bit. */
- type->set_fields
- ((struct field *) TYPE_ZALLOC (type, bit * sizeof (struct field)));
+ type->alloc_fields (bit);
+ type->set_num_fields (0);
return type;
}
@@ -5912,6 +5888,46 @@ type::fixed_point_scaling_factor ()
return type->fixed_point_info ().scaling_factor;
}
+void type::alloc_fields (unsigned int nfields, bool init)
+{
+ this->set_num_fields (nfields);
+
+ if (nfields == 0)
+ {
+ this->main_type->flds_bnds.fields = nullptr;
+ return;
+ }
+
+ size_t size = nfields * sizeof (*this->fields ());
+ struct field *fields
+ = (struct field *) (init
+ ? TYPE_ZALLOC (this, size)
+ : TYPE_ALLOC (this, size));
+
+ this->main_type->flds_bnds.fields = fields;
+}
+
+void type::copy_fields (struct type *src)
+{
+ unsigned int nfields = src->num_fields ();
+ alloc_fields (nfields, false);
+ if (nfields == 0)
+ return;
+
+ size_t size = nfields * sizeof (*this->fields ());
+ memcpy (this->fields (), src->fields (), size);
+}
+
+void type::copy_fields (std::vector<struct field> &src)
+{
+ unsigned int nfields = src.size ();
+ alloc_fields (nfields, false);
+ if (nfields == 0)
+ return;
+
+ size_t size = nfields * sizeof (*this->fields ());
+ memcpy (this->fields (), src.data (), size);
+}
\f
static const registry<gdbarch>::key<struct builtin_type> gdbtypes_data;
diff --git a/gdb/gdbtypes.h b/gdb/gdbtypes.h
index aedaf53cd5d..8f592dbe1c0 100644
--- a/gdb/gdbtypes.h
+++ b/gdb/gdbtypes.h
@@ -992,6 +992,14 @@ struct type
this->main_type->flds_bnds.fields = fields;
}
+ /* Allocate the fields array of this type, with NFIELDS elements. If INIT,
+ zero-initialize the allocated memory. */
+ void alloc_fields (unsigned int nfields, bool init = true);
+
+ /* Allocate the fields array of this type, and copy the fields from SRC. */
+ void copy_fields (struct type *src);
+ void copy_fields (std::vector<struct field> &src);
+
type *index_type () const
{
return this->field (0).type ();
diff --git a/gdb/gnu-v3-abi.c b/gdb/gnu-v3-abi.c
index 2c7c83e67b1..73b69da21e5 100644
--- a/gdb/gnu-v3-abi.c
+++ b/gdb/gnu-v3-abi.c
@@ -113,7 +113,6 @@ static struct type *
get_gdb_vtable_type (struct gdbarch *arch)
{
struct type *t;
- struct field *field_list, *field;
int offset;
struct type *result = vtable_type_gdbarch_data.get (arch);
@@ -131,50 +130,56 @@ get_gdb_vtable_type (struct gdbarch *arch)
struct type *ptrdiff_type
= init_integer_type (alloc, gdbarch_ptr_bit (arch), 0, "ptrdiff_t");
+ t = alloc.new_type (TYPE_CODE_STRUCT, 0, nullptr);
+
/* We assume no padding is necessary, since GDB doesn't know
anything about alignment at the moment. If this assumption bites
us, we should add a gdbarch method which, given a type, returns
the alignment that type requires, and then use that here. */
/* Build the field list. */
- field_list = XCNEWVEC (struct field, 4);
- field = &field_list[0];
+ t->alloc_fields (4);
+
offset = 0;
/* ptrdiff_t vcall_and_vbase_offsets[0]; */
- field->set_name ("vcall_and_vbase_offsets");
- field->set_type (lookup_array_range_type (ptrdiff_type, 0, -1));
- field->set_loc_bitpos (offset * TARGET_CHAR_BIT);
- offset += field->type ()->length ();
- field++;
+ {
+ struct field &field0 = t->field (0);
+ field0.set_name ("vcall_and_vbase_offsets");
+ field0.set_type (lookup_array_range_type (ptrdiff_type, 0, -1));
+ field0.set_loc_bitpos (offset * TARGET_CHAR_BIT);
+ offset += field0.type ()->length ();
+ }
/* ptrdiff_t offset_to_top; */
- field->set_name ("offset_to_top");
- field->set_type (ptrdiff_type);
- field->set_loc_bitpos (offset * TARGET_CHAR_BIT);
- offset += field->type ()->length ();
- field++;
+ {
+ struct field &field1 = t->field (1);
+ field1.set_name ("offset_to_top");
+ field1.set_type (ptrdiff_type);
+ field1.set_loc_bitpos (offset * TARGET_CHAR_BIT);
+ offset += field1.type ()->length ();
+ }
/* void *type_info; */
- field->set_name ("type_info");
- field->set_type (void_ptr_type);
- field->set_loc_bitpos (offset * TARGET_CHAR_BIT);
- offset += field->type ()->length ();
- field++;
+ {
+ struct field &field2 = t->field (2);
+ field2.set_name ("type_info");
+ field2.set_type (void_ptr_type);
+ field2.set_loc_bitpos (offset * TARGET_CHAR_BIT);
+ offset += field2.type ()->length ();
+ }
/* void (*virtual_functions[0]) (); */
- field->set_name ("virtual_functions");
- field->set_type (lookup_array_range_type (ptr_to_void_fn_type, 0, -1));
- field->set_loc_bitpos (offset * TARGET_CHAR_BIT);
- offset += field->type ()->length ();
- field++;
-
- /* We assumed in the allocation above that there were four fields. */
- gdb_assert (field == (field_list + 4));
-
- t = alloc.new_type (TYPE_CODE_STRUCT, offset * TARGET_CHAR_BIT, NULL);
- t->set_num_fields (field - field_list);
- t->set_fields (field_list);
+ {
+ struct field &field3 = t->field (3);
+ field3.set_name ("virtual_functions");
+ field3.set_type (lookup_array_range_type (ptr_to_void_fn_type, 0, -1));
+ field3.set_loc_bitpos (offset * TARGET_CHAR_BIT);
+ offset += field3.type ()->length ();
+ }
+
+ t->set_length (offset);
+
t->set_name ("gdb_gnu_v3_abi_vtable");
INIT_CPLUS_SPECIFIC (t);
@@ -1026,7 +1031,6 @@ static struct type *
build_std_type_info_type (struct gdbarch *arch)
{
struct type *t;
- struct field *field_list, *field;
int offset;
struct type *void_ptr_type
= builtin_type (arch)->builtin_data_ptr;
@@ -1035,30 +1039,32 @@ build_std_type_info_type (struct gdbarch *arch)
struct type *char_ptr_type
= make_pointer_type (make_cv_type (1, 0, char_type, NULL), NULL);
- field_list = XCNEWVEC (struct field, 2);
- field = &field_list[0];
+ t = type_allocator (arch).new_type (TYPE_CODE_STRUCT, 0, nullptr);
+
+ t->alloc_fields (2);
+
offset = 0;
/* The vtable. */
- field->set_name ("_vptr.type_info");
- field->set_type (void_ptr_type);
- field->set_loc_bitpos (offset * TARGET_CHAR_BIT);
- offset += field->type ()->length ();
- field++;
+ {
+ struct field &field0 = t->field (0);
+ field0.set_name ("_vptr.type_info");
+ field0.set_type (void_ptr_type);
+ field0.set_loc_bitpos (offset * TARGET_CHAR_BIT);
+ offset += field0.type ()->length ();
+ }
/* The name. */
- field->set_name ("__name");
- field->set_type (char_ptr_type);
- field->set_loc_bitpos (offset * TARGET_CHAR_BIT);
- offset += field->type ()->length ();
- field++;
-
- gdb_assert (field == (field_list + 2));
-
- t = type_allocator (arch).new_type (TYPE_CODE_STRUCT,
- offset * TARGET_CHAR_BIT, nullptr);
- t->set_num_fields (field - field_list);
- t->set_fields (field_list);
+ {
+ struct field &field1 = t->field (1);
+ field1.set_name ("__name");
+ field1.set_type (char_ptr_type);
+ field1.set_loc_bitpos (offset * TARGET_CHAR_BIT);
+ offset += field1.type ()->length ();
+ }
+
+ t->set_length (offset);
+
t->set_name ("gdb_gnu_v3_type_info");
INIT_CPLUS_SPECIFIC (t);
diff --git a/gdb/mdebugread.c b/gdb/mdebugread.c
index 40ebe6ae9c5..688501e157a 100644
--- a/gdb/mdebugread.c
+++ b/gdb/mdebugread.c
@@ -1034,9 +1034,7 @@ parse_symbol (SYMR *sh, union aux_ext *ax, char *ext_sh, int bigend,
t->set_code (type_code);
t->set_length (sh->value);
- t->set_num_fields (nfields);
- f = ((struct field *) TYPE_ALLOC (t, nfields * sizeof (struct field)));
- t->set_fields (f);
+ t->alloc_fields (nfields, false);
if (type_code == TYPE_CODE_ENUM)
{
@@ -1197,10 +1195,7 @@ parse_symbol (SYMR *sh, union aux_ext *ax, char *ext_sh, int bigend,
if (nparams > 0)
{
- ftype->set_num_fields (nparams);
- ftype->set_fields
- ((struct field *)
- TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
+ ftype->alloc_fields (nparams, false);
iparams = 0;
for (struct symbol *sym : block_iterator_range (cblock))
diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c
index 0e2ca090ba8..cacfea86ab1 100644
--- a/gdb/rust-lang.c
+++ b/gdb/rust-lang.c
@@ -950,9 +950,7 @@ rust_composite_type (struct type *original,
result->set_code (TYPE_CODE_STRUCT);
result->set_name (name);
- result->set_num_fields (nfields);
- result->set_fields
- ((struct field *) TYPE_ZALLOC (result, nfields * sizeof (struct field)));
+ result->alloc_fields (nfields);
i = 0;
bitpos = 0;
diff --git a/gdb/stabsread.c b/gdb/stabsread.c
index c3d87033f4f..c29d1c0d397 100644
--- a/gdb/stabsread.c
+++ b/gdb/stabsread.c
@@ -982,9 +982,7 @@ define_symbol (CORE_ADDR valu, const char *string, int desc, int type,
}
/* Allocate parameter information fields and fill them in. */
- ftype->set_fields
- ((struct field *)
- TYPE_ALLOC (ftype, nsemi * sizeof (struct field)));
+ ftype->alloc_fields (nsemi, false);
while (*p++ == ';')
{
struct type *ptype;
@@ -1826,10 +1824,7 @@ read_type (const char **pp, struct objfile *objfile)
&& arg_types->type->code () == TYPE_CODE_VOID)
num_args = 0;
- func_type->set_fields
- ((struct field *) TYPE_ALLOC (func_type,
- num_args * sizeof (struct field)));
- memset (func_type->fields (), 0, num_args * sizeof (struct field));
+ func_type->alloc_fields (num_args);
{
int i;
struct type_list *t;
@@ -3295,11 +3290,7 @@ attach_fields_to_type (struct stab_field_info *fip, struct type *type,
non-public fields. Record the field count, allocate space for the
array of fields, and create blank visibility bitfields if necessary. */
- type->set_num_fields (nfields);
- type->set_fields
- ((struct field *)
- TYPE_ALLOC (type, sizeof (struct field) * nfields));
- memset (type->fields (), 0, sizeof (struct field) * nfields);
+ type->alloc_fields (nfields);
if (non_public_fields)
{
@@ -3644,11 +3635,7 @@ read_enum_type (const char **pp, struct type *type,
type->set_is_stub (false);
if (unsigned_enum)
type->set_is_unsigned (true);
- type->set_num_fields (nsyms);
- type->set_fields
- ((struct field *)
- TYPE_ALLOC (type, sizeof (struct field) * nsyms));
- memset (type->fields (), 0, sizeof (struct field) * nsyms);
+ type->alloc_fields (nsyms);
/* Find the symbols for the values and put them into the type.
The symbols can be found in the symlist that we put them on
diff --git a/gdb/windows-tdep.c b/gdb/windows-tdep.c
index bc1927049d8..0414aea6f1a 100644
--- a/gdb/windows-tdep.c
+++ b/gdb/windows-tdep.c
@@ -745,9 +745,7 @@ create_enum (struct gdbarch *gdbarch, int bit, const char *name,
int i;
type = type_allocator (gdbarch).new_type (TYPE_CODE_ENUM, bit, name);
- type->set_num_fields (count);
- type->set_fields
- ((struct field *) TYPE_ZALLOC (type, sizeof (struct field) * count));
+ type->alloc_fields (count);
type->set_is_unsigned (true);
for (i = 0; i < count; i++)
--
2.35.3
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 3/6] [gdb/symtab] Do more zero-initialization of type::fields
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
2023-08-30 19:13 ` [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields} Tom de Vries
@ 2023-08-30 19:13 ` Tom de Vries
2023-08-30 20:19 ` Tom Tromey
2023-08-30 19:13 ` [PATCH 4/6] [gdb/symtab] Replace TYPE_ALLOC + memset with TYPE_ZALLOC Tom de Vries
` (3 subsequent siblings)
5 siblings, 1 reply; 14+ messages in thread
From: Tom de Vries @ 2023-08-30 19:13 UTC (permalink / raw)
To: gdb-patches
Now that we've introduced type::{alloc_fields,copy_fields}, the places where
no zero-initialization of allocated fields is done are easy to spot:
...
$ find gdb* -type f | grep -v ChangeLog | xargs grep alloc_fields | grep false
gdb/coffread.c: type->alloc_fields (nfields, false);
gdb/coffread.c: type->alloc_fields (nsyms, false);
gdb/stabsread.c: ftype->alloc_fields (nsemi, false);
gdb/gdbtypes.c: resolved_type->alloc_fields (nfields, false);
gdb/gdbtypes.c: alloc_fields (nfields, false);
gdb/gdbtypes.c: alloc_fields (nfields, false);
gdb/mdebugread.c: t->alloc_fields (nfields, false);
gdb/mdebugread.c: ftype->alloc_fields (nparams, false);
...
All hits in gdbtypes.c are ok. There are two hits in the two variants of
copy_fields, and there's already a comment for the third.
AFAICT, the other ones are not, so fix those by dropping the "false" argument.
Tested on x86_64-linux.
---
gdb/coffread.c | 4 ++--
gdb/mdebugread.c | 4 ++--
gdb/stabsread.c | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/gdb/coffread.c b/gdb/coffread.c
index e132dd1a1f7..e251f110ff8 100644
--- a/gdb/coffread.c
+++ b/gdb/coffread.c
@@ -2032,7 +2032,7 @@ coff_read_struct_type (int index, int length, int lastsym,
}
/* Now create the vector of fields, and record how big it is. */
- type->alloc_fields (nfields, false);
+ type->alloc_fields (nfields);
/* Copy the saved-up fields into the field vector. */
@@ -2110,7 +2110,7 @@ coff_read_enum_type (int index, int length, int lastsym,
else /* Assume ints. */
type->set_length (gdbarch_int_bit (gdbarch) / TARGET_CHAR_BIT);
type->set_code (TYPE_CODE_ENUM);
- type->alloc_fields (nsyms, false);
+ type->alloc_fields (nsyms);
/* Find the symbols for the values and put them into the type.
The symbols can be found in the symlist that we put them on
diff --git a/gdb/mdebugread.c b/gdb/mdebugread.c
index 688501e157a..ad9967b75fa 100644
--- a/gdb/mdebugread.c
+++ b/gdb/mdebugread.c
@@ -1034,7 +1034,7 @@ parse_symbol (SYMR *sh, union aux_ext *ax, char *ext_sh, int bigend,
t->set_code (type_code);
t->set_length (sh->value);
- t->alloc_fields (nfields, false);
+ t->alloc_fields (nfields);
if (type_code == TYPE_CODE_ENUM)
{
@@ -1195,7 +1195,7 @@ parse_symbol (SYMR *sh, union aux_ext *ax, char *ext_sh, int bigend,
if (nparams > 0)
{
- ftype->alloc_fields (nparams, false);
+ ftype->alloc_fields (nparams);
iparams = 0;
for (struct symbol *sym : block_iterator_range (cblock))
diff --git a/gdb/stabsread.c b/gdb/stabsread.c
index c29d1c0d397..ad9258a9f20 100644
--- a/gdb/stabsread.c
+++ b/gdb/stabsread.c
@@ -982,7 +982,7 @@ define_symbol (CORE_ADDR valu, const char *string, int desc, int type,
}
/* Allocate parameter information fields and fill them in. */
- ftype->alloc_fields (nsemi, false);
+ ftype->alloc_fields (nsemi);
while (*p++ == ';')
{
struct type *ptype;
--
2.35.3
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 4/6] [gdb/symtab] Replace TYPE_ALLOC + memset with TYPE_ZALLOC
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
2023-08-30 19:13 ` [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields} Tom de Vries
2023-08-30 19:13 ` [PATCH 3/6] [gdb/symtab] Do more zero-initialization of type::fields Tom de Vries
@ 2023-08-30 19:13 ` Tom de Vries
2023-08-30 20:20 ` Tom Tromey
2023-08-30 19:13 ` [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL " Tom de Vries
` (2 subsequent siblings)
5 siblings, 1 reply; 14+ messages in thread
From: Tom de Vries @ 2023-08-30 19:13 UTC (permalink / raw)
To: gdb-patches
I noticed a case or TYPE_ALLOC followed by memset.
Replace this with TYPE_ZALLOC.
Tested on x86_64-linux.
---
gdb/stabsread.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/gdb/stabsread.c b/gdb/stabsread.c
index ad9258a9f20..18fefd6929c 100644
--- a/gdb/stabsread.c
+++ b/gdb/stabsread.c
@@ -2693,9 +2693,7 @@ read_member_functions (struct stab_field_info *fip, const char **pp,
{
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_FN_FIELDLISTS (type) = (struct fn_fieldlist *)
- TYPE_ALLOC (type, sizeof (struct fn_fieldlist) * nfn_fields);
- memset (TYPE_FN_FIELDLISTS (type), 0,
- sizeof (struct fn_fieldlist) * nfn_fields);
+ TYPE_ZALLOC (type, sizeof (struct fn_fieldlist) * nfn_fields);
TYPE_NFN_FIELDS (type) = nfn_fields;
}
--
2.35.3
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL with TYPE_ZALLOC
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
` (2 preceding siblings ...)
2023-08-30 19:13 ` [PATCH 4/6] [gdb/symtab] Replace TYPE_ALLOC + memset with TYPE_ZALLOC Tom de Vries
@ 2023-08-30 19:13 ` Tom de Vries
2023-08-30 20:21 ` Tom Tromey
2023-08-30 19:13 ` [PATCH 6/6] [gdb/symtab] Replace TYPE_ALLOC with TYPE_ZALLOC where required Tom de Vries
2023-08-30 20:15 ` [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom Tromey
5 siblings, 1 reply; 14+ messages in thread
From: Tom de Vries @ 2023-08-30 19:13 UTC (permalink / raw)
To: gdb-patches
I noticed some cases of TYPE_ALLOC followed by B_CLRALL.
Replace these with TYPE_ZALLOC.
Tested on x86_64-linux.
---
gdb/dwarf2/read.c | 12 ++++--------
gdb/stabsread.c | 15 +++++----------
2 files changed, 9 insertions(+), 18 deletions(-)
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 7fe0e84cdda..bc68c290289 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -12064,16 +12064,13 @@ dwarf2_attach_fields_to_type (struct field_info *fip, struct type *type,
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_FIELD_PRIVATE_BITS (type) =
- (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
- B_CLRALL (TYPE_FIELD_PRIVATE_BITS (type), nfields);
+ (B_TYPE *) TYPE_ZALLOC (type, B_BYTES (nfields));
TYPE_FIELD_PROTECTED_BITS (type) =
- (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
- B_CLRALL (TYPE_FIELD_PROTECTED_BITS (type), nfields);
+ (B_TYPE *) TYPE_ZALLOC (type, B_BYTES (nfields));
TYPE_FIELD_IGNORE_BITS (type) =
- (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
- B_CLRALL (TYPE_FIELD_IGNORE_BITS (type), nfields);
+ (B_TYPE *) TYPE_ZALLOC (type, B_BYTES (nfields));
}
/* If the type has baseclasses, allocate and clear a bit vector for
@@ -12084,9 +12081,8 @@ dwarf2_attach_fields_to_type (struct field_info *fip, struct type *type,
unsigned char *pointer;
ALLOCATE_CPLUS_STRUCT_TYPE (type);
- pointer = (unsigned char *) TYPE_ALLOC (type, num_bytes);
+ pointer = (unsigned char *) TYPE_ZALLOC (type, num_bytes);
TYPE_FIELD_VIRTUAL_BITS (type) = pointer;
- B_CLRALL (TYPE_FIELD_VIRTUAL_BITS (type), fip->baseclasses.size ());
TYPE_N_BASECLASSES (type) = fip->baseclasses.size ();
}
diff --git a/gdb/stabsread.c b/gdb/stabsread.c
index 18fefd6929c..1269fc02d72 100644
--- a/gdb/stabsread.c
+++ b/gdb/stabsread.c
@@ -3067,19 +3067,17 @@ read_baseclasses (struct stab_field_info *fip, const char **pp,
/* Some stupid compilers have trouble with the following, so break
it up into simpler expressions. */
TYPE_FIELD_VIRTUAL_BITS (type) = (B_TYPE *)
- TYPE_ALLOC (type, B_BYTES (TYPE_N_BASECLASSES (type)));
+ TYPE_ZALLOC (type, B_BYTES (TYPE_N_BASECLASSES (type)));
#else
{
int num_bytes = B_BYTES (TYPE_N_BASECLASSES (type));
char *pointer;
- pointer = (char *) TYPE_ALLOC (type, num_bytes);
+ pointer = (char *) TYPE_ZALLOC (type, num_bytes);
TYPE_FIELD_VIRTUAL_BITS (type) = (B_TYPE *) pointer;
}
#endif /* 0 */
- B_CLRALL (TYPE_FIELD_VIRTUAL_BITS (type), TYPE_N_BASECLASSES (type));
-
for (i = 0; i < TYPE_N_BASECLASSES (type); i++)
{
newobj = OBSTACK_ZALLOC (&fip->obstack, struct stabs_nextfield);
@@ -3295,16 +3293,13 @@ attach_fields_to_type (struct stab_field_info *fip, struct type *type,
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_FIELD_PRIVATE_BITS (type) =
- (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
- B_CLRALL (TYPE_FIELD_PRIVATE_BITS (type), nfields);
+ (B_TYPE *) TYPE_ZALLOC (type, B_BYTES (nfields));
TYPE_FIELD_PROTECTED_BITS (type) =
- (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
- B_CLRALL (TYPE_FIELD_PROTECTED_BITS (type), nfields);
+ (B_TYPE *) TYPE_ZALLOC (type, B_BYTES (nfields));
TYPE_FIELD_IGNORE_BITS (type) =
- (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
- B_CLRALL (TYPE_FIELD_IGNORE_BITS (type), nfields);
+ (B_TYPE *) TYPE_ZALLOC (type, B_BYTES (nfields));
}
/* Copy the saved-up fields into the field vector. Start from the
--
2.35.3
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 6/6] [gdb/symtab] Replace TYPE_ALLOC with TYPE_ZALLOC where required
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
` (3 preceding siblings ...)
2023-08-30 19:13 ` [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL " Tom de Vries
@ 2023-08-30 19:13 ` Tom de Vries
2023-08-30 20:26 ` Tom Tromey
2023-08-30 20:15 ` [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom Tromey
5 siblings, 1 reply; 14+ messages in thread
From: Tom de Vries @ 2023-08-30 19:13 UTC (permalink / raw)
To: gdb-patches
Handle the remaining uses of TYPE_ALLOC, either by:
- replacing with TYPE_ZALLOC, or
- adding a comment explaining why zero-initialization is not necessary.
Tested on x86_64-linux.
---
gdb/dwarf2/read.c | 10 ++++++++--
gdb/gdbtypes.c | 8 +++++---
2 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index bc68c290289..527e0770502 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -12376,8 +12376,8 @@ dwarf2_attach_fn_fields_to_type (struct field_info *fip, struct type *type,
ALLOCATE_CPLUS_STRUCT_TYPE (type);
TYPE_FN_FIELDLISTS (type) = (struct fn_fieldlist *)
- TYPE_ALLOC (type,
- sizeof (struct fn_fieldlist) * fip->fnfieldlists.size ());
+ TYPE_ZALLOC (type,
+ sizeof (struct fn_fieldlist) * fip->fnfieldlists.size ());
for (int i = 0; i < fip->fnfieldlists.size (); i++)
{
@@ -12386,6 +12386,8 @@ dwarf2_attach_fn_fields_to_type (struct field_info *fip, struct type *type,
TYPE_FN_FIELDLIST_NAME (type, i) = nf.name;
TYPE_FN_FIELDLIST_LENGTH (type, i) = nf.fnfields.size ();
+ /* No need to zero-initialize, initialization is done by the copy in
+ the loop below. */
fn_flp->fn_fields = (struct fn_field *)
TYPE_ALLOC (type, sizeof (struct fn_field) * nf.fnfields.size ());
@@ -13088,6 +13090,8 @@ process_structure_scope (struct die_info *die, struct dwarf2_cu *cu)
int count = fi.typedef_field_list.size ();
ALLOCATE_CPLUS_STRUCT_TYPE (type);
+ /* No zero-initialization is need, the elements are initialized by
+ the copy in the loop below. */
TYPE_TYPEDEF_FIELD_ARRAY (type)
= ((struct decl_field *)
TYPE_ALLOC (type,
@@ -13106,6 +13110,8 @@ process_structure_scope (struct die_info *die, struct dwarf2_cu *cu)
int count = fi.nested_types_list.size ();
ALLOCATE_CPLUS_STRUCT_TYPE (type);
+ /* No zero-initialization is need, the elements are initialized by
+ the copy in the loop below. */
TYPE_NESTED_TYPES_ARRAY (type)
= ((struct decl_field *)
TYPE_ALLOC (type, sizeof (struct decl_field) * count));
diff --git a/gdb/gdbtypes.c b/gdb/gdbtypes.c
index 766107a7013..fd67c4bafdb 100644
--- a/gdb/gdbtypes.c
+++ b/gdb/gdbtypes.c
@@ -3207,7 +3207,7 @@ check_stub_method (struct type *type, int method_id, int signature_id)
/* We need one extra slot, for the THIS pointer. */
argtypes = (struct field *)
- TYPE_ALLOC (type, (argcount + 1) * sizeof (struct field));
+ TYPE_ZALLOC (type, (argcount + 1) * sizeof (struct field));
p = argtypetext;
/* Add THIS pointer for non-static methods. */
@@ -3297,7 +3297,7 @@ allocate_cplus_struct_type (struct type *type)
TYPE_SPECIFIC_FIELD (type) = TYPE_SPECIFIC_CPLUS_STUFF;
TYPE_RAW_CPLUS_SPECIFIC (type) = (struct cplus_struct_type *)
- TYPE_ALLOC (type, sizeof (struct cplus_struct_type));
+ TYPE_ZALLOC (type, sizeof (struct cplus_struct_type));
*(TYPE_RAW_CPLUS_SPECIFIC (type)) = cplus_struct_default;
set_type_vptr_fieldno (type, -1);
}
@@ -3314,7 +3314,7 @@ allocate_gnat_aux_type (struct type *type)
{
TYPE_SPECIFIC_FIELD (type) = TYPE_SPECIFIC_GNAT_STUFF;
TYPE_GNAT_SPECIFIC (type) = (struct gnat_aux_type *)
- TYPE_ALLOC (type, sizeof (struct gnat_aux_type));
+ TYPE_ZALLOC (type, sizeof (struct gnat_aux_type));
*(TYPE_GNAT_SPECIFIC (type)) = gnat_aux_default;
}
@@ -3454,6 +3454,8 @@ init_complex_type (const char *name, struct type *target_type)
{
if (name == nullptr && target_type->name () != nullptr)
{
+ /* No zero-initialization required, initialized by strcpy/strcat
+ below. */
char *new_name
= (char *) TYPE_ALLOC (target_type,
strlen (target_type->name ())
--
2.35.3
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
` (4 preceding siblings ...)
2023-08-30 19:13 ` [PATCH 6/6] [gdb/symtab] Replace TYPE_ALLOC with TYPE_ZALLOC where required Tom de Vries
@ 2023-08-30 20:15 ` Tom Tromey
5 siblings, 0 replies; 14+ messages in thread
From: Tom Tromey @ 2023-08-30 20:15 UTC (permalink / raw)
To: Tom de Vries via Gdb-patches; +Cc: Tom de Vries
>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> When running test-case gdb.dwarf2/per-bfd-sharing.exp with target board stabs,
Tom> gdb either segfaults or asserts due to reading uninitialized memory, allocated
Tom> here in buildsym_compunit::finish_block_internal:
Tom> ...
Tom> ftype-> set_fields
Tom> ((struct field *)
Tom> TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
Tom> ...
Tom> Fix this by using TYPE_ZALLOC instead.
At first I was curious about the history of what changed here, but now I
see that dwarf2_attach_fields_to_type is doing the zalloc thing, so I
think it's just the usual thing where nobody uses or tests non-DWARF
stuff (and why would they) so it wasn't caught in some earlier change.
Approved-By: Tom Tromey <tom@tromey.com>
Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields}
2023-08-30 19:13 ` [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields} Tom de Vries
@ 2023-08-30 20:17 ` Tom Tromey
2023-08-31 7:57 ` Tom de Vries
0 siblings, 1 reply; 14+ messages in thread
From: Tom Tromey @ 2023-08-30 20:17 UTC (permalink / raw)
To: Tom de Vries via Gdb-patches; +Cc: Tom de Vries
>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> After finding this code in buildsym_compunit::finish_block_internal:
Tom> ...
ftype-> set_fields
Tom> ((struct field *)
Tom> TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
Tom> ...
Tom> and fixing PR30810 by using TYPE_ZALLOC, I wondered if there were more
Tom> locations that needed fixing.
Tom> I decided to make things easier to spot by factoring out a new function
Tom> alloc_fields:
Thanks. Seems like a good idea to me.
Tom> +void type::alloc_fields (unsigned int nfields, bool init)
gdb style is a newline after the return type.
There's a few cases of this.
Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 3/6] [gdb/symtab] Do more zero-initialization of type::fields
2023-08-30 19:13 ` [PATCH 3/6] [gdb/symtab] Do more zero-initialization of type::fields Tom de Vries
@ 2023-08-30 20:19 ` Tom Tromey
0 siblings, 0 replies; 14+ messages in thread
From: Tom Tromey @ 2023-08-30 20:19 UTC (permalink / raw)
To: Tom de Vries via Gdb-patches; +Cc: Tom de Vries
>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> Now that we've introduced type::{alloc_fields,copy_fields}, the places where
Tom> no zero-initialization of allocated fields is done are easy to spot:
Tom> ...
Tom> $ find gdb* -type f | grep -v ChangeLog | xargs grep alloc_fields | grep false
Tom> gdb/coffread.c: type->alloc_fields (nfields, false);
Tom> gdb/coffread.c: type->alloc_fields (nsyms, false);
Tom> gdb/stabsread.c: ftype->alloc_fields (nsemi, false);
Tom> gdb/gdbtypes.c: resolved_type->alloc_fields (nfields, false);
Tom> gdb/gdbtypes.c: alloc_fields (nfields, false);
Tom> gdb/gdbtypes.c: alloc_fields (nfields, false);
Tom> gdb/mdebugread.c: t->alloc_fields (nfields, false);
Tom> gdb/mdebugread.c: ftype->alloc_fields (nparams, false);
Tom> ...
Tom> All hits in gdbtypes.c are ok. There are two hits in the two variants of
Tom> copy_fields, and there's already a comment for the third.
Tom> AFAICT, the other ones are not, so fix those by dropping the "false" argument.
Looks good.
Approved-By: Tom Tromey <tom@tromey.com>
Honestly it probably wouldn't hurt to just always zero-init these.
If type allocation is ever a performance problem, then I suspect
something's gone pretty wrong.
Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 4/6] [gdb/symtab] Replace TYPE_ALLOC + memset with TYPE_ZALLOC
2023-08-30 19:13 ` [PATCH 4/6] [gdb/symtab] Replace TYPE_ALLOC + memset with TYPE_ZALLOC Tom de Vries
@ 2023-08-30 20:20 ` Tom Tromey
0 siblings, 0 replies; 14+ messages in thread
From: Tom Tromey @ 2023-08-30 20:20 UTC (permalink / raw)
To: Tom de Vries via Gdb-patches; +Cc: Tom de Vries
>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> I noticed a case or TYPE_ALLOC followed by memset.
Tom> Replace this with TYPE_ZALLOC.
Tom> Tested on x86_64-linux.
Obvious IMO.
Approved-By: Tom Tromey <tom@tromey.com>
Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL with TYPE_ZALLOC
2023-08-30 19:13 ` [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL " Tom de Vries
@ 2023-08-30 20:21 ` Tom Tromey
2023-08-31 8:00 ` Tom de Vries
0 siblings, 1 reply; 14+ messages in thread
From: Tom Tromey @ 2023-08-30 20:21 UTC (permalink / raw)
To: Tom de Vries via Gdb-patches; +Cc: Tom de Vries
>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> I noticed some cases of TYPE_ALLOC followed by B_CLRALL.
Tom> Replace these with TYPE_ZALLOC.
Looks good.
I wonder if B_CLRALL is still used anywhere after this.
Approved-By: Tom Tromey <tom@tromey.com>
Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 6/6] [gdb/symtab] Replace TYPE_ALLOC with TYPE_ZALLOC where required
2023-08-30 19:13 ` [PATCH 6/6] [gdb/symtab] Replace TYPE_ALLOC with TYPE_ZALLOC where required Tom de Vries
@ 2023-08-30 20:26 ` Tom Tromey
0 siblings, 0 replies; 14+ messages in thread
From: Tom Tromey @ 2023-08-30 20:26 UTC (permalink / raw)
To: Tom de Vries via Gdb-patches; +Cc: Tom de Vries
>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
Tom> Handle the remaining uses of TYPE_ALLOC, either by:
Tom> - replacing with TYPE_ZALLOC, or
Tom> - adding a comment explaining why zero-initialization is not necessary.
Seems fine.
Approved-By: Tom Tromey <tom@tromey.com>
Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields}
2023-08-30 20:17 ` Tom Tromey
@ 2023-08-31 7:57 ` Tom de Vries
0 siblings, 0 replies; 14+ messages in thread
From: Tom de Vries @ 2023-08-31 7:57 UTC (permalink / raw)
To: Tom Tromey, Tom de Vries via Gdb-patches
On 8/30/23 22:17, Tom Tromey wrote:
>>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
>
> Tom> After finding this code in buildsym_compunit::finish_block_internal:
> Tom> ...
> ftype-> set_fields
> Tom> ((struct field *)
> Tom> TYPE_ALLOC (ftype, nparams * sizeof (struct field)));
> Tom> ...
> Tom> and fixing PR30810 by using TYPE_ZALLOC, I wondered if there were more
> Tom> locations that needed fixing.
>
> Tom> I decided to make things easier to spot by factoring out a new function
> Tom> alloc_fields:
>
> Thanks. Seems like a good idea to me.
>
> Tom> +void type::alloc_fields (unsigned int nfields, bool init)
>
> gdb style is a newline after the return type.
> There's a few cases of this.
Ack, fixed and pushed the series.
Thanks for the reviews.
- Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL with TYPE_ZALLOC
2023-08-30 20:21 ` Tom Tromey
@ 2023-08-31 8:00 ` Tom de Vries
0 siblings, 0 replies; 14+ messages in thread
From: Tom de Vries @ 2023-08-31 8:00 UTC (permalink / raw)
To: Tom Tromey, Tom de Vries via Gdb-patches
On 8/30/23 22:21, Tom Tromey wrote:
>>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:
>
> Tom> I noticed some cases of TYPE_ALLOC followed by B_CLRALL.
> Tom> Replace these with TYPE_ZALLOC.
>
> Looks good.
> I wonder if B_CLRALL is still used anywhere after this.
I guess not:
...
$ find gdb* -type f | egrep -v ChangeLog | xargs grep B_CLR
gdb/gdbtypes.h:#define B_CLR(a,x) ((a)[(x)>>3] &= ~(1 << ((x)&7)))
gdb/gdbtypes.h:#define B_CLRALL(a,x) memset ((a), 0, B_BYTES(x))
...
Thanks,
- Tom
^ permalink raw reply [flat|nested] 14+ messages in thread
end of thread, other threads:[~2023-08-31 8:00 UTC | newest]
Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-08-30 19:13 [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom de Vries
2023-08-30 19:13 ` [PATCH 2/6] [gdb/symtab] Factor out type::{alloc_fields,copy_fields} Tom de Vries
2023-08-30 20:17 ` Tom Tromey
2023-08-31 7:57 ` Tom de Vries
2023-08-30 19:13 ` [PATCH 3/6] [gdb/symtab] Do more zero-initialization of type::fields Tom de Vries
2023-08-30 20:19 ` Tom Tromey
2023-08-30 19:13 ` [PATCH 4/6] [gdb/symtab] Replace TYPE_ALLOC + memset with TYPE_ZALLOC Tom de Vries
2023-08-30 20:20 ` Tom Tromey
2023-08-30 19:13 ` [PATCH 5/6] [gdb/symtab] Replace TYPE_ALLOC + B_CLRALL " Tom de Vries
2023-08-30 20:21 ` Tom Tromey
2023-08-31 8:00 ` Tom de Vries
2023-08-30 19:13 ` [PATCH 6/6] [gdb/symtab] Replace TYPE_ALLOC with TYPE_ZALLOC where required Tom de Vries
2023-08-30 20:26 ` Tom Tromey
2023-08-30 20:15 ` [PATCH 1/6] [gdb/symtab] Fix uninitialized memory in buildsym_compunit::finish_block_internal Tom Tromey
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