From cf885b19579646d6a085470658bc83432d6786d2 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Fri, 7 Apr 2023 17:12:00 +0200 Subject: [PATCH] hw/xen: fix off-by-one in xen_evtchn_set_gsi() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Coverity points out (CID 1508128) a bounds checking error. We need to check for gsi >= IOAPIC_NUM_PINS, not just greater-than. Also fix up an assert() that has the same problem, that Coverity didn't see. Fixes: 4f81baa33ed6 ("hw/xen: Support GSI mapping to PIRQ") Signed-off-by: David Woodhouse Reviewed-by: Peter Maydell Reviewed-by: Philippe Mathieu-Daudé Message-Id: <20230801175747.145906-2-dwmw2@infradead.org> Signed-off-by: Philippe Mathieu-Daudé --- hw/i386/kvm/xen_evtchn.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/i386/kvm/xen_evtchn.c b/hw/i386/kvm/xen_evtchn.c index 3d810dbd59..0e9c108614 100644 --- a/hw/i386/kvm/xen_evtchn.c +++ b/hw/i386/kvm/xen_evtchn.c @@ -1587,7 +1587,7 @@ static int allocate_pirq(XenEvtchnState *s, int type, int gsi) found: pirq_inuse_word(s, pirq) |= pirq_inuse_bit(pirq); if (gsi >= 0) { - assert(gsi <= IOAPIC_NUM_PINS); + assert(gsi < IOAPIC_NUM_PINS); s->gsi_pirq[gsi] = pirq; } s->pirq[pirq].gsi = gsi; @@ -1601,7 +1601,7 @@ bool xen_evtchn_set_gsi(int gsi, int level) assert(qemu_mutex_iothread_locked()); - if (!s || gsi < 0 || gsi > IOAPIC_NUM_PINS) { + if (!s || gsi < 0 || gsi >= IOAPIC_NUM_PINS) { return false; }