The address of a packed member is not packed, which may cause accesses
to unaligned pointers.  Avoid this by reading the packed value before
passing it to another function.

Cc: Jason Wang <jasowang@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
        Resubmission of the patch at https://patchwork.kernel.org/patch/10160229/
        The vhost part has since been fixed independently (commit
        69aff03064, "vhost-user: fix misaligned access to payload",
        2018-01-18).

 hw/char/virtio-serial-bus.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
index d2dd8ab502..04e3ebe352 100644
--- a/hw/char/virtio-serial-bus.c
+++ b/hw/char/virtio-serial-bus.c
@@ -667,9 +667,9 @@ static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f)
 
     /* The config space (ignored on the far end in current versions) */
     get_config(vdev, (uint8_t *)&config);
-    qemu_put_be16s(f, &config.cols);
-    qemu_put_be16s(f, &config.rows);
-    qemu_put_be32s(f, &config.max_nr_ports);
+    qemu_put_be16(f, config.cols);
+    qemu_put_be16(f, config.rows);
+    qemu_put_be32(f, config.max_nr_ports);
 
     /* The ports map */
     max_nr_ports = s->serial.max_virtserial_ports;
-- 
2.17.1

On 9/26/18 11:20 PM, Paolo Bonzini wrote:
> The address of a packed member is not packed, which may cause accesses
> to unaligned pointers.  Avoid this by reading the packed value before
> passing it to another function.
> 
> Cc: Jason Wang <jasowang@redhat.com>
> Cc: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>         Resubmission of the patch at https://patchwork.kernel.org/patch/10160229/
>         The vhost part has since been fixed independently (commit
>         69aff03064, "vhost-user: fix misaligned access to payload",
>         2018-01-18).
> 
>  hw/char/virtio-serial-bus.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
> index d2dd8ab502..04e3ebe352 100644
> --- a/hw/char/virtio-serial-bus.c
> +++ b/hw/char/virtio-serial-bus.c
> @@ -667,9 +667,9 @@ static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f)
>  
>      /* The config space (ignored on the far end in current versions) */
>      get_config(vdev, (uint8_t *)&config);
> -    qemu_put_be16s(f, &config.cols);
> -    qemu_put_be16s(f, &config.rows);
> -    qemu_put_be32s(f, &config.max_nr_ports);
> +    qemu_put_be16(f, config.cols);
> +    qemu_put_be16(f, config.rows);
> +    qemu_put_be32(f, config.max_nr_ports);

Clever.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

>  
>      /* The ports map */
>      max_nr_ports = s->serial.max_virtserial_ports;
> 

On 2018年09月27日 05:20, Paolo Bonzini wrote:
> The address of a packed member is not packed, which may cause accesses
> to unaligned pointers.  Avoid this by reading the packed value before
> passing it to another function.
>
> Cc: Jason Wang <jasowang@redhat.com>
> Cc: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>          Resubmission of the patch at https://patchwork.kernel.org/patch/10160229/
>          The vhost part has since been fixed independently (commit
>          69aff03064, "vhost-user: fix misaligned access to payload",
>          2018-01-18).
>
>   hw/char/virtio-serial-bus.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
> index d2dd8ab502..04e3ebe352 100644
> --- a/hw/char/virtio-serial-bus.c
> +++ b/hw/char/virtio-serial-bus.c
> @@ -667,9 +667,9 @@ static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f)
>   
>       /* The config space (ignored on the far end in current versions) */
>       get_config(vdev, (uint8_t *)&config);
> -    qemu_put_be16s(f, &config.cols);
> -    qemu_put_be16s(f, &config.rows);
> -    qemu_put_be32s(f, &config.max_nr_ports);
> +    qemu_put_be16(f, config.cols);
> +    qemu_put_be16(f, config.rows);
> +    qemu_put_be32(f, config.max_nr_ports);
>   
>       /* The ports map */
>       max_nr_ports = s->serial.max_virtserial_ports;

Acked-by: Jason Wang <jasowang@redhat.com>