Re: [Qemu-devel] [PATCH 1/2] qga-win: prevent crash when executing fsinfo command

[Philippe Mathieu-Daudé]

On 06/26/2018 12:10 PM, Sameeh Jubran wrote:
> From: Sameeh Jubran <address@hidden>
> 
> The fsinfo command is currently implemented for Windows only and it's disk
> parameter can be enabled by adding the define "CONFIG_QGA_NTDDSCSI" to the qga
> code. When enabled and executed the qemu-ga crashed with the following 
> message:
> 
> ------------------------------------------------
> File qapi/qapi-visit-core.c, Line 49
> 
> Expression: !(v->type & VISITOR_OUTPUT) || *obj)
> ------------------------------------------------

Due to these multiple lines starting with '---', this patch confuses
Thunderbird + colorediffs extension in a funny way...

> 
> After some digging, turns out that the GuestPCIAddress is null and the
> qapi visitor doesn't like that, so we can always allocate it instead and
> initiate all it's members to -1.
> 
> Signed-off-by: Sameeh Jubran <address@hidden>

Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

> ---
>  qga/commands-win32.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/qga/commands-win32.c b/qga/commands-win32.c
> index 2d48394748..c5f1c884e1 100644
> --- a/qga/commands-win32.c
> +++ b/qga/commands-win32.c
> @@ -485,6 +485,11 @@ static GuestPCIAddress *get_pci_info(char *guid, Error 
> **errp)
>      char *buffer = NULL;
>      GuestPCIAddress *pci = NULL;
>      char *name = g_strdup(&guid[4]);
> +    pci = g_malloc0(sizeof(*pci));
> +    pci->domain = -1;
> +    pci->slot = -1;
> +    pci->function = -1;
> +    pci->bus = -1;
>  
>      if (!QueryDosDevice(name, dev_name, ARRAY_SIZE(dev_name))) {
>          error_setg_win32(errp, GetLastError(), "failed to get dos device 
> name");
> @@ -556,7 +561,6 @@ static GuestPCIAddress *get_pci_info(char *guid, Error 
> **errp)
>  
>          func = addr & 0x0000FFFF;
>          dev = (addr >> 16) & 0x0000FFFF;
> -        pci = g_malloc0(sizeof(*pci));
>          pci->domain = dev;
>          pci->slot = slot;
>          pci->function = func;
>