merge revision(s) b8a3f1bd45:

Fix crash in tracing object allocations

	ObjectSpace.trace_object_allocations_start could crash since it adds a
	TracePoint for when objects are freed. However, TracePoint could crash
	since it modifies st tables while inside the GC that is trying to free
	the object. This could cause a memory allocation to happen which would
	crash if it triggers another GC.

	See a crash log: http://ci.rvm.jp/results/trunk@ruby-sp1/4373707
	---
	 ext/objspace/depend           | 1 +
	 ext/objspace/object_tracing.c | 7 +++++++
	 gc.h                          | 4 ++--
	 3 files changed, 10 insertions(+), 2 deletions(-)
This commit is contained in:
nagachika 2024-01-18 12:57:01 +09:00
parent 3302e251dc
commit 99c9aeef4b
4 changed files with 11 additions and 3 deletions

View file

@ -158,6 +158,7 @@ object_tracing.o: $(hdrdir)/ruby/missing.h
object_tracing.o: $(hdrdir)/ruby/ruby.h
object_tracing.o: $(hdrdir)/ruby/st.h
object_tracing.o: $(hdrdir)/ruby/subst.h
object_tracing.o: $(top_srcdir)/gc.h
object_tracing.o: $(top_srcdir)/internal.h
object_tracing.o: object_tracing.c
object_tracing.o: objspace.h

View file

@ -13,6 +13,7 @@
**********************************************************************/
#include "gc.h"
#include "internal.h"
#include "ruby/debug.h"
#include "objspace.h"
@ -121,6 +122,10 @@ freeobj_i(VALUE tpval, void *data)
st_data_t v;
struct allocation_info *info;
/* Modifying the st table can cause allocations, which can trigger GC.
* Since freeobj_i is called during GC, it must not trigger another GC. */
VALUE gc_disabled = rb_gc_disable_no_rest();
if (arg->keep_remains) {
if (st_lookup(arg->object_table, obj, &v)) {
info = (struct allocation_info *)v;
@ -135,6 +140,8 @@ freeobj_i(VALUE tpval, void *data)
ruby_xfree(info);
}
}
if (gc_disabled == Qfalse) rb_gc_enable();
}
static int

4
gc.h
View file

@ -116,8 +116,6 @@ int ruby_get_stack_grow_direction(volatile VALUE *addr);
const char *rb_obj_info(VALUE obj);
const char *rb_raw_obj_info(char *const buff, const size_t buff_size, VALUE obj);
VALUE rb_gc_disable_no_rest(void);
struct rb_thread_struct;
size_t rb_size_pool_slot_size(unsigned char pool_id);
@ -142,6 +140,8 @@ void rb_objspace_each_objects_without_setup(
size_t rb_gc_obj_slot_size(VALUE obj);
VALUE rb_gc_disable_no_rest(void);
RUBY_SYMBOL_EXPORT_END
#endif /* RUBY_GC_H */

View file

@ -11,7 +11,7 @@
# define RUBY_VERSION_MINOR RUBY_API_VERSION_MINOR
#define RUBY_VERSION_TEENY 2
#define RUBY_RELEASE_DATE RUBY_RELEASE_YEAR_STR"-"RUBY_RELEASE_MONTH_STR"-"RUBY_RELEASE_DAY_STR
#define RUBY_PATCHLEVEL 155
#define RUBY_PATCHLEVEL 156
#include "ruby/version.h"
#include "ruby/internal/abi.h"