Re: [PATCH 1/2] util/main-loop: Fix maximum number of wait objects for win32

[Bin Meng]

On Tue, Aug 9, 2022 at 9:15 PM Marc-André Lureau
 wrote:
>
> Hi
>
> On Fri, Aug 5, 2022 at 6:57 PM Bin Meng  wrote:
>>
>> From: Bin Meng 
>>
>> The maximum number of wait objects for win32 should be
>> MAXIMUM_WAIT_OBJECTS, not MAXIMUM_WAIT_OBJECTS + 1.
>>
>> Signed-off-by: Bin Meng 
>
>
> Nack,
>
> if wait_objects.num reaches MAXIMUM_WAIT_OBJECTS,
>
> then qemu_del_wait_object() will iterate up to it, and then the branch "if 
> (found)" will access the arrays at position i+1 == MAXIMUM_WAIT_OBJECTS.
>
> Note that the add functions should probably learn to avoid adding the same 
> HANDLE twice, otherwise del is a bit broken.
>

Thanks for the review. Will fix in v2.

Regards,
Bin

Re: [PATCH 1/2] util/main-loop: Fix maximum number of wait objects for win32

[Marc-André Lureau]

Hi

On Fri, Aug 5, 2022 at 6:57 PM Bin Meng  wrote:

> From: Bin Meng 
>
> The maximum number of wait objects for win32 should be
> MAXIMUM_WAIT_OBJECTS, not MAXIMUM_WAIT_OBJECTS + 1.
>
> Signed-off-by: Bin Meng 
>

Nack,

if wait_objects.num reaches MAXIMUM_WAIT_OBJECTS,

then qemu_del_wait_object() will iterate up to it, and then the branch "if
(found)" will access the arrays at position i+1 == MAXIMUM_WAIT_OBJECTS.

Note that the add functions should probably learn to avoid adding the same
HANDLE twice, otherwise del is a bit broken.

---
>
>  util/main-loop.c | 8 
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/util/main-loop.c b/util/main-loop.c
> index f00a25451b..f15d8e7d12 100644
> --- a/util/main-loop.c
> +++ b/util/main-loop.c
> @@ -363,10 +363,10 @@ void qemu_del_polling_cb(PollingFunc *func, void
> *opaque)
>  /* Wait objects support */
>  typedef struct WaitObjects {
>  int num;
> -int revents[MAXIMUM_WAIT_OBJECTS + 1];
> -HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
> -WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
> -void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
> +int revents[MAXIMUM_WAIT_OBJECTS];
> +HANDLE events[MAXIMUM_WAIT_OBJECTS];
> +WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS];
> +void *opaque[MAXIMUM_WAIT_OBJECTS];
>  } WaitObjects;
>
>  static WaitObjects wait_objects = {0};
> --
> 2.34.1
>
>
>

-- 
Marc-André Lureau

Re: [PATCH 1/2] util/main-loop: Fix maximum number of wait objects for win32

[Philippe Mathieu-Daudé via]

On Mon, Aug 8, 2022 at 5:56 PM Bin Meng  wrote:
> On Fri, Aug 5, 2022 at 10:56 PM Bin Meng  wrote:
> >
> > From: Bin Meng 
> >
> > The maximum number of wait objects for win32 should be
> > MAXIMUM_WAIT_OBJECTS, not MAXIMUM_WAIT_OBJECTS + 1.
> >
> > Signed-off-by: Bin Meng 
> > ---
> >
> >  util/main-loop.c | 8 
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> >
>
> Ping?

Reviewed-by: Philippe Mathieu-Daudé 

NB: qemu_del_wait_object() seems dubious in case the same handle is
added more than once with qemu_add_wait_object().

Re: [PATCH 1/2] util/main-loop: Fix maximum number of wait objects for win32

[Bin Meng]

On Fri, Aug 5, 2022 at 10:56 PM Bin Meng  wrote:
>
> From: Bin Meng 
>
> The maximum number of wait objects for win32 should be
> MAXIMUM_WAIT_OBJECTS, not MAXIMUM_WAIT_OBJECTS + 1.
>
> Signed-off-by: Bin Meng 
> ---
>
>  util/main-loop.c | 8 
>  1 file changed, 4 insertions(+), 4 deletions(-)
>

Ping?

[PATCH 1/2] util/main-loop: Fix maximum number of wait objects for win32

[Bin Meng]

From: Bin Meng 

The maximum number of wait objects for win32 should be
MAXIMUM_WAIT_OBJECTS, not MAXIMUM_WAIT_OBJECTS + 1.

Signed-off-by: Bin Meng 
---

 util/main-loop.c | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/util/main-loop.c b/util/main-loop.c
index f00a25451b..f15d8e7d12 100644
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -363,10 +363,10 @@ void qemu_del_polling_cb(PollingFunc *func, void *opaque)
 /* Wait objects support */
 typedef struct WaitObjects {
 int num;
-int revents[MAXIMUM_WAIT_OBJECTS + 1];
-HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
-WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
-void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
+int revents[MAXIMUM_WAIT_OBJECTS];
+HANDLE events[MAXIMUM_WAIT_OBJECTS];
+WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS];
+void *opaque[MAXIMUM_WAIT_OBJECTS];
 } WaitObjects;
 
 static WaitObjects wait_objects = {0};
-- 
2.34.1