diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2014-09-15 14:52:58 +0200 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2014-09-22 11:39:21 +0100 |
| commit | a90d411e63ef29bb99b984e0fdb7796aeee1c724 (patch) | |
| tree | d581f7df415e00711bb29d65438c6e76e849d941 | |
| parent | 0722eba9450cb8be9713fec1caa0772330739586 (diff) | |
aio-win32: avoid out-of-bounds access to the events array
If ret is WAIT_TIMEOUT and there was an event returned by select(),
we can write to a location after the end of the array. But in
that case we can retry the WaitForMultipleObjects call with the
same set of events, so just move the event[ret - WAIT_OBJECT_0]
assignment inside the existin conditional.
Reported-by: TeLeMan <geleman@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: TeLeMan <geleman@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
| -rw-r--r-- | aio-win32.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/aio-win32.c b/aio-win32.c index 7daeae18f1..d81313b00b 100644 --- a/aio-win32.c +++ b/aio-win32.c @@ -335,6 +335,7 @@ bool aio_poll(AioContext *ctx, bool blocking) event = NULL; if ((DWORD) (ret - WAIT_OBJECT_0) < count) { event = events[ret - WAIT_OBJECT_0]; + events[ret - WAIT_OBJECT_0] = events[--count]; } else if (!have_select_revents) { break; } @@ -343,9 +344,6 @@ bool aio_poll(AioContext *ctx, bool blocking) blocking = false; progress |= aio_dispatch_handlers(ctx, event); - - /* Try again, but only call each handler once. */ - events[ret - WAIT_OBJECT_0] = events[--count]; } progress |= timerlistgroup_run_timers(&ctx->tlg); |