fake_{loc,loclists,addr}_cu are Dwarf_CUs that are created separate from
all the others, so their contents are minimal and mostly initialized by
a calloc. On dwarf_end however, they are freed through the same code path
as all the others, so they call DAH_free like all the others. This changes
that so that these three are exempt from DAH and split-DWARF matters, and
swaps the calloc for a malloc so Memcheck will catch any others.
---
Sorry to keep adding patches, but ran across this while tinkering about.
Its not a current issue, but when the concurrent hash table is integrated this
could cause some issues (on some system somewhere, maybe). In that case there
are enough moving internals that a calloc may not initialize it properly.
Its also an error waiting to happen, so this is this just cleans it up with
some semblance of logical correctness.
(In other news, I finally figured out why git send-email wasn't working for me!
Thanks for everyone's patience, especially Wielaard's :) )
libdw/dwarf_begin_elf.c | 15 ++++++++++++---
libdw/dwarf_end.c | 22 +++++++++++++---------
2 files changed, 25 insertions(+), 12 deletions(-)
diff --git a/libdw/dwarf_begin_elf.c b/libdw/dwarf_begin_elf.c
index 8d137414..1b2c5a45 100644
--- a/libdw/dwarf_begin_elf.c
+++ b/libdw/dwarf_begin_elf.c
@@ -223,7 +223,7 @@ valid_p (Dwarf *result)
inside the .debug_loc or .debug_loclists section. */
if (result != NULL && result->sectiondata[IDX_debug_loc] != NULL)
{
- result->fake_loc_cu = (Dwarf_CU *) calloc (1, sizeof (Dwarf_CU));
+ result->fake_loc_cu = (Dwarf_CU *) malloc (sizeof (Dwarf_CU));
if (unlikely (result->fake_loc_cu == NULL))
{
Dwarf_Sig8_Hash_free (&result->sig8_hash);
@@ -240,12 +240,15 @@ valid_p (Dwarf *result)
result->fake_loc_cu->endp
= (result->sectiondata[IDX_debug_loc]->d_buf
+ result->sectiondata[IDX_debug_loc]->d_size);
+ result->fake_loc_cu->locs = NULL;
+ result->fake_loc_cu->address_size = 0;
+ result->fake_loc_cu->version = 0;
}
}
if (result != NULL && result->sectiondata[IDX_debug_loclists] != NULL)
{
- result->fake_loclists_cu = (Dwarf_CU *) calloc (1, sizeof (Dwarf_CU));
+ result->fake_loclists_cu = (Dwarf_CU *) malloc (sizeof (Dwarf_CU));
if (unlikely (result->fake_loclists_cu == NULL))
{
Dwarf_Sig8_Hash_free (&result->sig8_hash);
@@ -263,6 +266,9 @@ valid_p (Dwarf *result)
result->fake_loclists_cu->endp
= (result->sectiondata[IDX_debug_loclists]->d_buf
+ result->sectiondata[IDX_debug_loclists]->d_size);
+ result->fake_loclists_cu->locs = NULL;
+ result->fake_loclists_cu->address_size = 0;
+ result->fake_loclists_cu->version = 0;
}
}
@@ -272,7 +278,7 @@ valid_p (Dwarf *result)
inside the .debug_addr section, if it exists. */
if (result != NULL && result->sectiondata[IDX_debug_addr] != NULL)
{
- result->fake_addr_cu = (Dwarf_CU *) calloc (1, sizeof (Dwarf_CU));
+ result->fake_addr_cu = (Dwarf_CU *) malloc (sizeof (Dwarf_CU));
if (unlikely (result->fake_addr_cu == NULL))
{
Dwarf_Sig8_Hash_free (&result->sig8_hash);
@@ -291,6 +297,9 @@ valid_p (Dwarf *result)
result->fake_addr_cu->endp
= (result->sectiondata[IDX_debug_addr]->d_buf
+ result->sectiondata[IDX_debug_addr]->d_size);
+ result->fake_addr_cu->locs = NULL;
+ result->fake_addr_cu->address_size = 0;
+ result->fake_addr_cu->version = 0;
}
}
diff --git a/libdw/dwarf_end.c b/libdw/dwarf_end.c
index a2e94436..a32a149e 100644
--- a/libdw/dwarf_end.c
+++ b/libdw/dwarf_end.c
@@ -52,18 +52,22 @@ cu_free (void *arg)
{
struct Dwarf_CU *p = (struct Dwarf_CU *) arg;
- Dwarf_Abbrev_Hash_free (&p->abbrev_hash);
-
tdestroy (p->locs, noop_free);
- /* Free split dwarf one way (from skeleton to split). */
- if (p->unit_type == DW_UT_skeleton
- && p->split != NULL && p->split != (void *)-1)
+ if(p != p->dbg->fake_loc_cu && p != p->dbg->fake_loclists_cu
+ && p != p->dbg->fake_addr_cu)
{
- /* The fake_addr_cu might be shared, only release one. */
- if (p->dbg->fake_addr_cu == p->split->dbg->fake_addr_cu)
- p->split->dbg->fake_addr_cu = NULL;
- INTUSE(dwarf_end) (p->split->dbg);
+ Dwarf_Abbrev_Hash_free (&p->abbrev_hash);
+
+ /* Free split dwarf one way (from skeleton to split). */
+ if (p->unit_type == DW_UT_skeleton
+ && p->split != NULL && p->split != (void *)-1)
+ {
+ /* The fake_addr_cu might be shared, only release one. */
+ if (p->dbg->fake_addr_cu == p->split->dbg->fake_addr_cu)
+ p->split->dbg->fake_addr_cu = NULL;
+ INTUSE(dwarf_end) (p->split->dbg);
+ }
}
}
--
2.24.0.rc1
