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ASAN: Support coroutine context switching and stack tracing (#4153)

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For coroutine, we should use `__sanitizer_start_switch_fiber` which
similar to`VALGRIND_STACK_REGISTER`, see
https://github.com/google/sanitizers/issues/189#issuecomment-1346243598
for details. If not fix this, asan will output warning:

```
==72269==WARNING: ASan is ignoring requested __asan_handle_no_return: stack type: default top: 0x00016f638000; bottom 0x000106bec000; size: 0x000068a4c000 (1755627520)
False positive error reports may follow
For details see https://github.com/google/sanitizers/issues/189
```

It will cause asan failed to get the stack, see
`research/st/asan-switch.cpp` for example:

```
==71611==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x000103600733 at pc 0x0001009d3d7c bp 0x000100b4bd40 sp 0x000100b4bd38
WRITE of size 1 at 0x000103600733 thread T0
    #0 0x1009d3d78 in foo(void*) asan-switch.cpp:13
```

After fix this issue, it should provide the full stack when crashing:

```
==73437==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x000103300733 at pc 0x000100693d7c bp 0x00016f76f550 sp 0x00016f76f548
WRITE of size 1 at 0x000103300733 thread T0
    #0 0x100693d78 in foo(void*) asan-switch.cpp:13
    #1 0x100693df4 in main asan-switch.cpp:23
    #2 0x195aa20dc  (<unknown module>)
```

For primordial coroutine, if not set the stack by
`st_set_primordial_stack`, then the stack is NULL and asan can't get the
stack tracing. Note that it's optional and only make it fail to display
the stack information, no other errors.

---

Co-authored-by: john <hondaxiao@tencent.com>
This commit is contained in:
Winlin 2024-08-22 17:12:39 +08:00 • committed by GitHub
parent 55610cf689
commit 8f48a0e2d1
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15 changed files with 236 additions and 15 deletions
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76
trunk/3rdparty/st-srs/common.h vendored
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@ -162,6 +162,10 @@ struct _st_thread {
_st_clist_t tlink; /* For putting on thread queue */
#endif
#ifdef MD_ASAN
void *fake_stack; /* Fake stack for ASAN */
#endif
st_utime_t due; /* Wakeup time when thread is sleeping */
_st_thread_t *left; /* For putting in timeout heap */
_st_thread_t *right; /* -- see docs/timeout_heap.txt for details */
@ -314,7 +318,7 @@ extern __thread _st_eventsys_t *_st_eventsys;
* Forward declarations
*/
void _st_vp_schedule(void);
void _st_vp_schedule(_st_thread_t *from);
void _st_vp_check_clock(void);
void *_st_idle_thread_start(void *arg);
void _st_thread_main(void);
@ -365,6 +369,64 @@ _st_thread_t *st_thread_create(void *(*start)(void *arg), void *arg, int joinabl
#define ST_SWITCH_IN_CB(_thread)
#endif
#ifdef MD_ASAN
/*
* Fiber annotation interface.
*
* Before switching to a different stack, one must call
* __sanitizer_start_switch_fiber with a pointer to the bottom of the
* destination stack and its size. When code starts running on the new stack,
* it must call __sanitizer_finish_switch_fiber to finalize the switch.
* The start_switch function takes a void** to store the current fake stack if
* there is one (it is needed when detect_stack_use_after_return is enabled).
* When restoring a stack, this pointer must be given to the finish_switch
* function. In most cases, this void* can be stored on the stack just before
* switching. When leaving a fiber definitely, null must be passed as first
* argument to the start_switch function so that the fake stack is destroyed.
* If you do not want support for stack use-after-return detection, you can
* always pass null to these two functions.
* Note that the fake stack mechanism is disabled during fiber switch, so if a
* signal callback runs during the switch, it will not benefit from the stack
* use-after-return detection.
*
* See https://github.com/google/sanitizers/issues/189#issuecomment-1346243598
*/
extern void __sanitizer_start_switch_fiber(void **fake_stack_save,
const void *bottom, size_t size);
extern void __sanitizer_finish_switch_fiber(void *fake_stack_save,
const void **bottom_old,
size_t *size_old);
/* The stack for primoridal thread. */
extern void *_st_primordial_stack_bottom;
extern size_t _st_primordial_stack_size;
static inline void _st_asan_start_switch(_st_thread_t *from, _st_thread_t *thread)
{
/* For primordial thread, the stack is NULL, so asan can not capture it. */
const void *stk_bottom = thread->stack ? thread->stack->stk_bottom : NULL;
size_t stk_size = thread->stack ? thread->stack->stk_size : 0;
/* For primordial thread, user should setup the stack information. */
if (!stk_bottom && (thread->flags & _ST_FL_PRIMORDIAL)) {
stk_bottom = _st_primordial_stack_bottom;
stk_size = _st_primordial_stack_size;
}
/*
* Save the current stack to fake_stack of from, tell asan the target stack
* we are targeting to switch to.
*/
__sanitizer_start_switch_fiber(&from->fake_stack, stk_bottom, stk_size);
}
static inline void _st_asan_finish_switch(_st_thread_t *thread)
{
__sanitizer_finish_switch_fiber(thread->fake_stack, NULL, NULL);
}
#endif
/*
* Switch away from the current thread context by saving its state and
* calling the thread scheduler
@ -374,9 +436,14 @@ static inline void _st_switch_context(_st_thread_t *thread)
ST_SWITCH_OUT_CB(thread);
if (!_st_md_cxt_save(thread->context)) {
_st_vp_schedule();
_st_vp_schedule(thread);
}
#ifdef MD_ASAN
/* Switch from other thread to this running thread. */
_st_asan_finish_switch(thread);
#endif
ST_DEBUG_ITERATE_THREADS();
ST_SWITCH_IN_CB(thread);
}
@ -385,8 +452,11 @@ static inline void _st_switch_context(_st_thread_t *thread)
* Restore a thread context that was saved by _st_switch_context or
* initialized by _ST_INIT_CONTEXT
*/
static inline void _st_restore_context(_st_thread_t *thread)
static inline void _st_restore_context(_st_thread_t *from, _st_thread_t *thread)
{
#ifdef MD_ASAN
_st_asan_start_switch(from, thread);
#endif
_st_this_thread = thread;
_st_md_cxt_restore(thread->context, 1);
}