Re: [PATCH] hw/char/exynos4210_uart: Fix memleaks in exynos4210_uart_init

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 2/12/20 4:36 AM, kuhn.chenqun@huawei.com wrote:
> From: Chen Qun <kuhn.chenqun@huawei.com>
> 
> It's easy to reproduce as follow:
> virsh qemu-monitor-command vm1 --pretty '{"execute": "device-list-properties",
> "arguments":{"typename":"exynos4210.uart"}}'
> 
> ASAN shows memory leak stack:
>    #1 0xfffd896d71cb in g_malloc0 (/lib64/libglib-2.0.so.0+0x571cb)
>    #2 0xaaad270beee3 in timer_new_full /qemu/include/qemu/timer.h:530
>    #3 0xaaad270beee3 in timer_new /qemu/include/qemu/timer.h:551
>    #4 0xaaad270beee3 in timer_new_ns /qemu/include/qemu/timer.h:569
>    #5 0xaaad270beee3 in exynos4210_uart_init /qemu/hw/char/exynos4210_uart.c:677
>    #6 0xaaad275c8f4f in object_initialize_with_type /qemu/qom/object.c:516
>    #7 0xaaad275c91bb in object_new_with_type /qemu/qom/object.c:684
>    #8 0xaaad2755df2f in qmp_device_list_properties /qemu/qom/qom-qmp-cmds.c:152
> 
> Reported-by: Euler Robot <euler.robot@huawei.com>
> Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
> ---
>   hw/char/exynos4210_uart.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/char/exynos4210_uart.c b/hw/char/exynos4210_uart.c
> index 25d6588e41..5048db5410 100644
> --- a/hw/char/exynos4210_uart.c
> +++ b/hw/char/exynos4210_uart.c
> @@ -674,10 +674,6 @@ static void exynos4210_uart_init(Object *obj)
>       SysBusDevice *dev = SYS_BUS_DEVICE(obj);
>       Exynos4210UartState *s = EXYNOS4210_UART(dev);
>   
> -    s->fifo_timeout_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
> -                                         exynos4210_uart_timeout_int, s);
> -    s->wordtime = NANOSECONDS_PER_SECOND * 10 / 9600;

Why are you moving s->wordtime from init() to realize()?

> -
>       /* memory mapping */
>       memory_region_init_io(&s->iomem, obj, &exynos4210_uart_ops, s,
>                             "exynos4210.uart", EXYNOS4210_UART_REGS_MEM_SIZE);
> @@ -691,6 +687,10 @@ static void exynos4210_uart_realize(DeviceState *dev, Error **errp)
>   {
>       Exynos4210UartState *s = EXYNOS4210_UART(dev);
>   
> +    s->fifo_timeout_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
> +                                         exynos4210_uart_timeout_int, s);
> +    s->wordtime = NANOSECONDS_PER_SECOND * 10 / 9600;
> +
>       qemu_chr_fe_set_handlers(&s->chr, exynos4210_uart_can_receive,
>                                exynos4210_uart_receive, exynos4210_uart_event,
>                                NULL, s, NULL, true);
>