[gdb/f20] Fix memory errors with demangled name hash (Tom Tromey).
Jan Kratochvil
jankratochvil at fedoraproject.org
Mon Jun 30 22:14:57 UTC 2014
commit 01d3c9fc039e11d1ca4bd0a29e4b1600abf5e9c8
Author: Jan Kratochvil <jan.kratochvil at redhat.com>
Date: Tue Jul 1 00:15:01 2014 +0200
Fix memory errors with demangled name hash (Tom Tromey).
gdb-upstream.patch | 211 ++++++++++++++++++++++++++++++++++++++++++++++++++++
gdb.spec | 5 +-
2 files changed, 215 insertions(+), 1 deletions(-)
---
diff --git a/gdb-upstream.patch b/gdb-upstream.patch
index 6d82704..fcaf74c 100644
--- a/gdb-upstream.patch
+++ b/gdb-upstream.patch
@@ -102,3 +102,214 @@ Date: Tue May 13 14:55:53 2014 +0200
}
}
+
+
+
+http://sourceware.org/ml/gdb-patches/2014-06/msg00550.html
+Subject: Re: ASAN crash regression [Re: [PATCH 2/2] move the demangled_names_hash into the per-BFD]
+
+Jan> ./configure ... -fsanitize=address
+Jan> echo 'void f(){}main(){}'|gcc -x c++ - -g;ASAN_OPTIONS=symbolize=1 ASAN_SYMBOLIZER_PATH=/usr/bin/llvm-symbolizer ./gdb -batch a.out -ex 'file a.out'
+
+Readily seen with valgrind as well.
+
+Here's my proposed fix.
+
+Tom
+
+commit 3a93a67ad0ea3495f67c9708673345b73de2d806
+Author: Tom Tromey <tromey at redhat.com>
+Date: Mon Jun 16 03:17:19 2014 -0600
+
+ fix memory errors with demangled name hash
+
+ This fixes a regression that Jan pointed out.
+
+ The bug is that some names were allocated by dwarf2read on the objfile
+ obstack, but then passed to SYMBOL_SET_NAMES with copy_name=0. This
+ violates the invariant that the names must have a lifetime tied to the
+ lifetime of the BFD.
+
+ The fix is to allocate names on the per-BFD obstack.
+
+ I looked at all callers, direct or indirect, of SYMBOL_SET_NAMES that
+ pass copy_name=0. Note that only the ELF and DWARF readers do this;
+ other symbol readers were never updated (and perhaps cannot be,
+ depending on the details of the formats). This is why the patch is
+ relatively small.
+
+ Built and regtested on x86-64 Fedora 20.
+
+ 2014-06-16 Tom Tromey <tromey at redhat.com>
+
+ * dwarf2read.c (fixup_go_packaging, dwarf2_compute_name)
+ (dwarf2_physname, read_partial_die)
+ (guess_partial_die_structure_name, fixup_partial_die)
+ (guess_full_die_structure_name, anonymous_struct_prefix)
+ (dwarf2_name): Use per-BFD obstack.
+
+### a/gdb/ChangeLog
+### b/gdb/ChangeLog
+## -1,5 +1,13 @@
+ 2014-06-16 Tom Tromey <tromey at redhat.com>
+
++ * dwarf2read.c (fixup_go_packaging, dwarf2_compute_name)
++ (dwarf2_physname, read_partial_die)
++ (guess_partial_die_structure_name, fixup_partial_die)
++ (guess_full_die_structure_name, anonymous_struct_prefix)
++ (dwarf2_name): Use per-BFD obstack.
++
++2014-06-16 Tom Tromey <tromey at redhat.com>
++
+ * minsyms.h (prim_record_minimal_symbol)
+ (prim_record_minimal_symbol_and_info): Update comments.
+
+--- a/gdb/dwarf2read.c
++++ b/gdb/dwarf2read.c
+@@ -7745,9 +7745,10 @@ fixup_go_packaging (struct dwarf2_cu *cu)
+ if (package_name != NULL)
+ {
+ struct objfile *objfile = cu->objfile;
+- const char *saved_package_name = obstack_copy0 (&objfile->objfile_obstack,
+- package_name,
+- strlen (package_name));
++ const char *saved_package_name
++ = obstack_copy0 (&objfile->per_bfd->storage_obstack,
++ package_name,
++ strlen (package_name));
+ struct type *type = init_type (TYPE_CODE_MODULE, 0, 0,
+ saved_package_name, objfile);
+ struct symbol *sym;
+@@ -8365,6 +8366,8 @@ dwarf2_compute_name (const char *name,
+ long length;
+ const char *prefix;
+ struct ui_file *buf;
++ char *intermediate_name;
++ const char *canonical_name = NULL;
+
+ prefix = determine_prefix (die, cu);
+ buf = mem_fileopen ();
+@@ -8541,19 +8544,25 @@ dwarf2_compute_name (const char *name,
+ }
+ }
+
+- name = ui_file_obsavestring (buf, &objfile->objfile_obstack,
+- &length);
++ intermediate_name = ui_file_xstrdup (buf, &length);
+ ui_file_delete (buf);
+
+ if (cu->language == language_cplus)
+- {
+- const char *cname
+- = dwarf2_canonicalize_name (name, cu,
+- &objfile->objfile_obstack);
++ canonical_name
++ = dwarf2_canonicalize_name (intermediate_name, cu,
++ &objfile->per_bfd->storage_obstack);
++
++ /* If we only computed INTERMEDIATE_NAME, or if
++ INTERMEDIATE_NAME is already canonical, then we need to
++ copy it to the appropriate obstack. */
++ if (canonical_name == NULL || canonical_name == intermediate_name)
++ name = obstack_copy0 (&objfile->per_bfd->storage_obstack,
++ intermediate_name,
++ strlen (intermediate_name));
++ else
++ name = canonical_name;
+
+- if (cname != NULL)
+- name = cname;
+- }
++ xfree (intermediate_name);
+ }
+ }
+
+@@ -8562,7 +8571,7 @@ dwarf2_compute_name (const char *name,
+
+ /* Return the fully qualified name of DIE, based on its DW_AT_name.
+ If scope qualifiers are appropriate they will be added. The result
+- will be allocated on the objfile_obstack, or NULL if the DIE does
++ will be allocated on the storage_obstack, or NULL if the DIE does
+ not have a name. NAME may either be from a previous call to
+ dwarf2_name or NULL.
+
+@@ -8677,7 +8686,8 @@ dwarf2_physname (const char *name, struct die_info *die, struct dwarf2_cu *cu)
+ retval = canon;
+
+ if (need_copy)
+- retval = obstack_copy0 (&objfile->objfile_obstack, retval, strlen (retval));
++ retval = obstack_copy0 (&objfile->per_bfd->storage_obstack,
++ retval, strlen (retval));
+
+ do_cleanups (back_to);
+ return retval;
+@@ -15508,7 +15518,7 @@ read_partial_die (const struct die_reader_specs *reader,
+ default:
+ part_die->name
+ = dwarf2_canonicalize_name (DW_STRING (&attr), cu,
+- &objfile->objfile_obstack);
++ &objfile->per_bfd->storage_obstack);
+ break;
+ }
+ break;
+@@ -15793,7 +15803,7 @@ guess_partial_die_structure_name (struct partial_die_info *struct_pdi,
+ if (actual_class_name != NULL)
+ {
+ struct_pdi->name
+- = obstack_copy0 (&cu->objfile->objfile_obstack,
++ = obstack_copy0 (&cu->objfile->per_bfd->storage_obstack,
+ actual_class_name,
+ strlen (actual_class_name));
+ xfree (actual_class_name);
+@@ -15879,8 +15889,9 @@ fixup_partial_die (struct partial_die_info *part_die,
+ else
+ base = demangled;
+
+- part_die->name = obstack_copy0 (&cu->objfile->objfile_obstack,
+- base, strlen (base));
++ part_die->name
++ = obstack_copy0 (&cu->objfile->per_bfd->storage_obstack,
++ base, strlen (base));
+ xfree (demangled);
+ }
+ }
+@@ -18557,7 +18568,7 @@ guess_full_die_structure_name (struct die_info *die, struct dwarf2_cu *cu)
+ && actual_name[actual_name_len
+ - die_name_len - 1] == ':')
+ name =
+- obstack_copy0 (&cu->objfile->objfile_obstack,
++ obstack_copy0 (&cu->objfile->per_bfd->storage_obstack,
+ actual_name,
+ actual_name_len - die_name_len - 2);
+ }
+@@ -18603,7 +18614,7 @@ anonymous_struct_prefix (struct die_info *die, struct dwarf2_cu *cu)
+ if (base == NULL || base == DW_STRING (attr) || base[-1] != ':')
+ return "";
+
+- return obstack_copy0 (&cu->objfile->objfile_obstack,
++ return obstack_copy0 (&cu->objfile->per_bfd->storage_obstack,
+ DW_STRING (attr), &base[-1] - DW_STRING (attr));
+ }
+
+@@ -18943,8 +18954,9 @@ dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
+ char *base;
+
+ /* FIXME: we already did this for the partial symbol... */
+- DW_STRING (attr) = obstack_copy0 (&cu->objfile->objfile_obstack,
+- demangled, strlen (demangled));
++ DW_STRING (attr)
++ = obstack_copy0 (&cu->objfile->per_bfd->storage_obstack,
++ demangled, strlen (demangled));
+ DW_STRING_IS_CANONICAL (attr) = 1;
+ xfree (demangled);
+
+@@ -18967,7 +18979,7 @@ dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
+ {
+ DW_STRING (attr)
+ = dwarf2_canonicalize_name (DW_STRING (attr), cu,
+- &cu->objfile->objfile_obstack);
++ &cu->objfile->per_bfd->storage_obstack);
+ DW_STRING_IS_CANONICAL (attr) = 1;
+ }
+ return DW_STRING (attr);
+
diff --git a/gdb.spec b/gdb.spec
index 0d871b4..d66f3ed 100644
--- a/gdb.spec
+++ b/gdb.spec
@@ -39,7 +39,7 @@ Version: 7.7.1
# The release always contains a leading reserved number, start it at 1.
# `upstream' is not a part of `name' to stay fully rpm dependencies compatible for the testing.
-Release: 14%{?dist}
+Release: 15%{?dist}
License: GPLv3+ and GPLv3+ with exceptions and GPLv2+ and GPLv2+ with exceptions and GPL+ and LGPLv2+ and BSD and Public Domain and GFDL
Group: Development/Debuggers
@@ -1408,6 +1408,9 @@ fi
%endif # 0%{!?el5:1} || "%{_target_cpu}" == "noarch"
%changelog
+* Tue Jul 1 2014 Jan Kratochvil <jan.kratochvil at redhat.com> - 7.7.1-15.fc21
+- Fix memory errors with demangled name hash (Tom Tromey).
+
* Mon Jun 30 2014 Jan Kratochvil <jan.kratochvil at redhat.com> - 7.7.1-14.fc21
- Fix crash on optimized-out entry data values (BZ 1111910).
More information about the scm-commits
mailing list