| Message ID | 20220824085231.1630804-3-bmeng.cn@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/3] util/main-loop: Fix maximum number of wait objects for win32 | expand |
On 24/8/22 10:52, Bin Meng wrote: > From: Bin Meng <bin.meng@windriver.com> > > WaitForMultipleObjects() can only wait for MAXIMUM_WAIT_OBJECTS > object handles. Correct the event array size in aio_poll() and > add a assert() to ensure it does not cause out of bound access. > > Signed-off-by: Bin Meng <bin.meng@windriver.com> > Reviewed-by: Stefan Weil <sw@weilnetz.de> > Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > > (no changes since v2) > > Changes in v2: > - change 'count' to unsigned > > util/aio-win32.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
On Wed, Aug 24, 2022 at 04:52:31PM +0800, Bin Meng wrote: > From: Bin Meng <bin.meng@windriver.com> > > WaitForMultipleObjects() can only wait for MAXIMUM_WAIT_OBJECTS > object handles. Correct the event array size in aio_poll() and > add a assert() to ensure it does not cause out of bound access. > > Signed-off-by: Bin Meng <bin.meng@windriver.com> > Reviewed-by: Stefan Weil <sw@weilnetz.de> > Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > > (no changes since v2) > > Changes in v2: > - change 'count' to unsigned > > util/aio-win32.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/util/aio-win32.c b/util/aio-win32.c > index 44003d645e..80cfe012ad 100644 > --- a/util/aio-win32.c > +++ b/util/aio-win32.c > @@ -326,9 +326,9 @@ void aio_dispatch(AioContext *ctx) > bool aio_poll(AioContext *ctx, bool blocking) > { > AioHandler *node; > - HANDLE events[MAXIMUM_WAIT_OBJECTS + 1]; > + HANDLE events[MAXIMUM_WAIT_OBJECTS]; Interestingly, the orignial + 1 was entirely pointless, since the aio_poll impl has no bounds checking at all, until your new assert. > bool progress, have_select_revents, first; > - int count; > + unsigned count; > int timeout; > > /* > @@ -369,6 +369,7 @@ bool aio_poll(AioContext *ctx, bool blocking) > QLIST_FOREACH_RCU(node, &ctx->aio_handlers, node) { > if (!node->deleted && node->io_notify > && aio_node_check(ctx, node->is_external)) { > + assert(count < MAXIMUM_WAIT_OBJECTS); > events[count++] = event_notifier_get_handle(node->e); > } > } Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> With regards, Daniel
diff --git a/util/aio-win32.c b/util/aio-win32.c index 44003d645e..80cfe012ad 100644 --- a/util/aio-win32.c +++ b/util/aio-win32.c @@ -326,9 +326,9 @@ void aio_dispatch(AioContext *ctx) bool aio_poll(AioContext *ctx, bool blocking) { AioHandler *node; - HANDLE events[MAXIMUM_WAIT_OBJECTS + 1]; + HANDLE events[MAXIMUM_WAIT_OBJECTS]; bool progress, have_select_revents, first; - int count; + unsigned count; int timeout; /* @@ -369,6 +369,7 @@ bool aio_poll(AioContext *ctx, bool blocking) QLIST_FOREACH_RCU(node, &ctx->aio_handlers, node) { if (!node->deleted && node->io_notify && aio_node_check(ctx, node->is_external)) { + assert(count < MAXIMUM_WAIT_OBJECTS); events[count++] = event_notifier_get_handle(node->e); } }