From: Marcelo Tosatti <mtosatti@redhat.com>
Date: Sun, 18 Oct 2009 01:47:23 +0000 (-0300)
Subject: KVM: fix irq_source_id size verification
X-Git-Tag: firefly_0821_release~11625^2~603
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=310c1a04807321c666445292db4b9147f1174c08;p=firefly-linux-kernel-4.4.55.git

KVM: fix irq_source_id size verification

commit cd5a2685de4a642fd0bd763e8c19711ef08dbe27 upstream.

find_first_zero_bit works with bit numbers, not bytes.

Fixes

https://sourceforge.net/tracker/?func=detail&aid=2847560&group_id=180599&atid=893831

Reported-by: "Xu, Jiajun" <jiajun.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index 001663ff401a..03e5b217e88b 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -205,10 +205,9 @@ int kvm_request_irq_source_id(struct kvm *kvm)
 	int irq_source_id;
 
 	mutex_lock(&kvm->irq_lock);
-	irq_source_id = find_first_zero_bit(bitmap,
-				sizeof(kvm->arch.irq_sources_bitmap));
+	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
 
-	if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
+	if (irq_source_id >= BITS_PER_LONG) {
 		printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
 		return -EFAULT;
 	}
@@ -228,7 +227,7 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 
 	mutex_lock(&kvm->irq_lock);
 	if (irq_source_id < 0 ||
-	    irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
+	    irq_source_id >= BITS_PER_LONG) {
 		printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
 		return;
 	}