| Message ID | 20210716102239.96-2-xieyongji@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] vhost-vdpa: Fix integer overflow in vhost_vdpa_process_iotlb_update() | expand |
在 2021/7/16 下午6:22, Xie Yongji 写道: > This fixes the incorrect calculation for integer overflow > when the last address of iova range is 0xffffffff. > > Fixes: ec33d031a14b ("vhost: detect 32 bit integer wrap around“) > Reported-by: Jason Wang <jasowang@redhat.com> > Signed-off-by: Xie Yongji <xieyongji@bytedance.com> > --- > drivers/vhost/vhost.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index b9e853e6094d..a9fd1b311d2f 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -738,7 +738,8 @@ static bool log_access_ok(void __user *log_base, u64 addr, unsigned long sz) > static bool vhost_overflow(u64 uaddr, u64 size) > { > /* Make sure 64 bit math will not overflow. */ > - return uaddr > ULONG_MAX || size > ULONG_MAX || uaddr > ULONG_MAX - size; > + return uaddr > ULONG_MAX || size > ULONG_MAX || > + uaddr - 1 > ULONG_MAX - size; > } Acked-by: Jason Wang <jasowang@redhat.com> > > /* Caller should have vq mutex and device mutex. */
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index b9e853e6094d..a9fd1b311d2f 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -738,7 +738,8 @@ static bool log_access_ok(void __user *log_base, u64 addr, unsigned long sz) static bool vhost_overflow(u64 uaddr, u64 size) { /* Make sure 64 bit math will not overflow. */ - return uaddr > ULONG_MAX || size > ULONG_MAX || uaddr > ULONG_MAX - size; + return uaddr > ULONG_MAX || size > ULONG_MAX || + uaddr - 1 > ULONG_MAX - size; } /* Caller should have vq mutex and device mutex. */
This fixes the incorrect calculation for integer overflow when the last address of iova range is 0xffffffff. Fixes: ec33d031a14b ("vhost: detect 32 bit integer wrap around“) Reported-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Xie Yongji <xieyongji@bytedance.com> --- drivers/vhost/vhost.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)