From 4ba8f0dc993953d3ddda6328e3ef17a2fc2cbde5 Mon Sep 17 00:00:00 2001 From: KJ Tsanaktsidis Date: Sun, 12 Nov 2023 13:24:55 +1100 Subject: Pass down "stack start" variables from closer to the top of the stack The implementation of `native_thread_init_stack` for the various threading models can use the address of a local variable as part of the calculation of the machine stack extents: * pthreads uses it as a lower-bound on the start of the stack, because glibc (and maybe other libcs) can store its own data on the stack before calling into user code on thread creation. * win32 uses it as an argument to VirtualQuery, which gets the extent of the memory mapping which contains the variable However, the local being used for this is actually allocated _inside_ the `native_thread_init_stack` frame; that means the caller might allocate a VALUE on the stack that actually lies outside the bounds stored in machine.stack_{start,end}. A local variable from one level above the topmost frame that stores VALUEs on the stack must be drilled down into the call to `native_thread_init_stack` to be used in the calculation. This probably doesn't _really_ matter for the win32 case (they'll be in the same memory mapping so VirtualQuery should return the same thing), but definitely could matter for the pthreads case. [Bug #20001] --- vm_core.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'vm_core.h') diff --git a/vm_core.h b/vm_core.h index 354603514e..91cfae77e9 100644 --- a/vm_core.h +++ b/vm_core.h @@ -1842,7 +1842,7 @@ rb_control_frame_t *rb_vm_get_binding_creatable_next_cfp(const rb_execution_cont VALUE *rb_vm_svar_lep(const rb_execution_context_t *ec, const rb_control_frame_t *cfp); int rb_vm_get_sourceline(const rb_control_frame_t *); void rb_vm_stack_to_heap(rb_execution_context_t *ec); -void ruby_thread_init_stack(rb_thread_t *th); +void ruby_thread_init_stack(rb_thread_t *th, void *local_in_parent_frame); rb_thread_t * ruby_thread_from_native(void); int ruby_thread_set_native(rb_thread_t *th); int rb_vm_control_frame_id_and_class(const rb_control_frame_t *cfp, ID *idp, ID *called_idp, VALUE *klassp); -- cgit v1.2.3