1berry/ruby
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

cont.c: handle errors for getcontext()

Browse Source 
It may raise an error in a certain security configuration.
It is very likely to trigger a segmentation fault if `getcontext()` failed silently
and we just let it keep going.

Related to https://bugs.ruby-lang.org/issues/14883
[Fix GH-1903]

Based on the patch from Lion Yang <lion@aosc.io>

From: Lion Yang <lion@aosc.io>

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63835 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
nobu 2018-07-03 05:12:52 +00:00
parent b03c1d087b
commit 8fc203ba5f
1 changed files with 12 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
cont.c
View File

@ -142,14 +142,21 @@ enum fiber_status {
#define FIBER_RUNNABLE_P(fib) (FIBER_CREATED_P(fib) || FIBER_SUSPENDED_P(fib)) #define FIBER_RUNNABLE_P(fib) (FIBER_CREATED_P(fib) || FIBER_SUSPENDED_P(fib))
#if FIBER_USE_NATIVE && !defined(_WIN32) #if FIBER_USE_NATIVE && !defined(_WIN32)
static inline void static inline int
fiber_context_create(ucontext_t *context, void (*func)(), void *arg, void *ptr, size_t size) fiber_context_create(ucontext_t *context, void (*func)(), void *arg, void *ptr, size_t size)
{ {
getcontext(context); if (getcontext(context) < 0) return -1;
/*
* getcontext() may fail by some reasons:
* 1. SELinux policy banned one of "rt_sigprocmask",
* "sigprocmask" or "swapcontext";
* 2. libseccomp (aka. syscall filter) banned one of them.
*/
context->uc_link = NULL; context->uc_link = NULL;
context->uc_stack.ss_sp = ptr; context->uc_stack.ss_sp = ptr;
context->uc_stack.ss_size = size; context->uc_stack.ss_size = size;
makecontext(context, func, 0); makecontext(context, func, 0);
return 0;
} }
#endif #endif
@ -856,7 +863,9 @@ fiber_initialize_machine_stack_context(rb_fiber_t *fib, size_t size)
ptr = fiber_machine_stack_alloc(size); ptr = fiber_machine_stack_alloc(size);
fib->ss_sp = ptr; fib->ss_sp = ptr;
fib->ss_size = size; fib->ss_size = size;
fiber_context_create(&fib->context, fiber_entry, NULL, fib->ss_sp, fib->ss_size); if (fiber_context_create(&fib->context, fiber_entry, NULL, fib->ss_sp, fib->ss_size)) {
rb_raise(rb_eFiberError, "can't get context for creating fiber: %s", ERRNOMSG);
}
sec->machine.stack_start = (VALUE*)(ptr + STACK_DIR_UPPER(0, size)); sec->machine.stack_start = (VALUE*)(ptr + STACK_DIR_UPPER(0, size));
sec->machine.stack_maxsize = size - RB_PAGE_SIZE; sec->machine.stack_maxsize = size - RB_PAGE_SIZE;
#endif #endif