From 032e56fbd66d3dd1aa144a86f4a90b667dcff649 Mon Sep 17 00:00:00 2001 From: kosaki Date: Wed, 6 Jul 2011 12:29:09 +0000 Subject: [PATCH] * cont.c (fiber_machine_stack_alloc): fix mprotect misuse. A stack guard page should have PROT_NONE. * cont.c (fiber_initialize_machine_stack_context): th->machine_stack_maxsize shouldn't be included guard pages size. [Bug #4983][ruby-dev:44043] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@32421 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- ChangeLog | 8 ++++++++ cont.c | 9 ++++++--- 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/ChangeLog b/ChangeLog index 3f0f4f3bc8..2370e92d7b 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +Wed Jul 6 21:24:53 2011 KOSAKI Motohiro + + * cont.c (fiber_machine_stack_alloc): fix mprotect misuse. A stack + guard page should have PROT_NONE. + * cont.c (fiber_initialize_machine_stack_context): + th->machine_stack_maxsize shouldn't be included guard pages size. + [Bug #4983][ruby-dev:44043] + Wed Jul 6 21:23:38 2011 KOSAKI Motohiro * cont.c (fiber_machine_stack_alloc): use MAP_STACK if it's provided. diff --git a/cont.c b/cont.c index e46f52ccf0..beaa5c8e5f 100644 --- a/cont.c +++ b/cont.c @@ -543,12 +543,15 @@ fiber_machine_stack_alloc(size_t size) else { void *page; STACK_GROW_DIR_DETECTION; + ptr = mmap(NULL, size, PROT_READ | PROT_WRITE, FIBER_STACK_FLAGS, -1, 0); if (ptr == MAP_FAILED) { rb_raise(rb_eFiberError, "can't alloc machine stack to fiber"); } + + /* guard page setup */ page = ptr + STACK_DIR_UPPER((size - RB_PAGE_SIZE) / sizeof(VALUE), 0); - if (mprotect(page, RB_PAGE_SIZE, PROT_READ | PROT_WRITE) < 0) { + if (mprotect(page, RB_PAGE_SIZE, PROT_NONE) < 0) { rb_raise(rb_eFiberError, "mprotect failed"); } } @@ -572,6 +575,7 @@ fiber_initialize_machine_stack_context(rb_fiber_t *fib, size_t size) rb_raise(rb_eFiberError, "can't create fiber"); } } + sth->machine_stack_maxsize = size; #else /* not WIN32 */ ucontext_t *context = &fib->context; VALUE *ptr; @@ -584,9 +588,8 @@ fiber_initialize_machine_stack_context(rb_fiber_t *fib, size_t size) context->uc_stack.ss_size = size; makecontext(context, rb_fiber_start, 0); sth->machine_stack_start = ptr + STACK_DIR_UPPER(0, size / sizeof(VALUE)); + sth->machine_stack_maxsize = size - RB_PAGE_SIZE; #endif - - sth->machine_stack_maxsize = size; #ifdef __ia64 sth->machine_register_stack_maxsize = sth->machine_stack_maxsize; #endif