RE: [PATCH] Make sure fixed size CHAR arrays can fit MAX_ULONGs

[Paul Durrant <xadimgnik@xxxxxxxxx>]

> -----Original Message-----
> From: win-pv-devel <win-pv-devel-bounces@xxxxxxxxxxxxxxxxxxxx> On Behalf Of 
> Owen Smith
> Sent: 27 April 2020 11:39
> To: win-pv-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: Owen Smith <owen.smith@xxxxxxxxxx>
> Subject: [PATCH] Make sure fixed size CHAR arrays can fit MAX_ULONGs
> 
> When formatting strings with %u, make sure the target buffer is large
> enough to contain MAX_ULONG.
> 
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>

Acked-by: Paul Durrant <paul@xxxxxxx>

> ---
>  src/xenvif/fdo.c      | 4 +++-
>  src/xenvif/frontend.c | 8 ++++++--
>  src/xenvif/mac.c      | 4 +++-
>  3 files changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/src/xenvif/fdo.c b/src/xenvif/fdo.c
> index 00e0c8a..896107c 100644
> --- a/src/xenvif/fdo.c
> +++ b/src/xenvif/fdo.c
> @@ -801,7 +801,7 @@ __FdoEnumerate(
> 
>          if (Device->Length != 0) {
>              ULONG   Number;
> -            CHAR    Prefix[sizeof ("device/vif/XX")];
> +            CHAR    Prefix[sizeof ("device/vif/XXXXXXXXXX")];
>              PCHAR   Address;
> 
>              Number = strtol(Device->Buffer, NULL, 10);
> @@ -811,6 +811,8 @@ __FdoEnumerate(
>                                          "device/vif/%u",
>                                          Number);
>              ASSERT(NT_SUCCESS(status));
> +            if (!NT_SUCCESS(status))
> +                continue;
> 
>              status = XENBUS_STORE(Read,
>                                    &Fdo->StoreInterface,
> diff --git a/src/xenvif/frontend.c b/src/xenvif/frontend.c
> index 0ed68df..ffd6111 100644
> --- a/src/xenvif/frontend.c
> +++ b/src/xenvif/frontend.c
> @@ -706,7 +706,7 @@ FrontendDumpAddressTable(
>          switch (Frontend->AddressTable[Index].si_family) {
>          case AF_INET: {
>              IPV4_ADDRESS    Address;
> -            CHAR            Node[sizeof ("ipv4/XXXXXXXX")];
> +            CHAR            Node[sizeof ("ipv4/XXXXXXXXXX")];
> 
>              RtlCopyMemory(Address.Byte,
>                            
> &Frontend->AddressTable[Index].Ipv4.sin_addr.s_addr,
> @@ -717,6 +717,8 @@ FrontendDumpAddressTable(
>                                          "ipv4/%u",
>                                          IpVersion4Count);
>              ASSERT(NT_SUCCESS(status));
> +            if (!NT_SUCCESS(status))
> +                continue;
> 
>              status = XENBUS_STORE(Printf,
>                                    &Frontend->StoreInterface,
> @@ -736,7 +738,7 @@ FrontendDumpAddressTable(
>          }
>          case AF_INET6: {
>              IPV6_ADDRESS    Address;
> -            CHAR            Node[sizeof ("ipv6/XXXXXXXX")];
> +            CHAR            Node[sizeof ("ipv6/XXXXXXXXXX")];
> 
>              RtlCopyMemory(Address.Byte,
>                            
> &Frontend->AddressTable[Index].Ipv6.sin6_addr.s6_addr,
> @@ -747,6 +749,8 @@ FrontendDumpAddressTable(
>                                          "ipv6/%u",
>                                          IpVersion6Count);
>              ASSERT(NT_SUCCESS(status));
> +            if (!NT_SUCCESS(status))
> +                continue;
> 
>              status = XENBUS_STORE(Printf,
>                                    &Frontend->StoreInterface,
> diff --git a/src/xenvif/mac.c b/src/xenvif/mac.c
> index 19666fe..3301ef9 100644
> --- a/src/xenvif/mac.c
> +++ b/src/xenvif/mac.c
> @@ -357,13 +357,15 @@ MacDumpAddressTable(
>                          "mac");
> 
>      for (Index = 0; Index < Count; Index++) {
> -        CHAR    Node[sizeof ("mac/XX")];
> +        CHAR    Node[sizeof ("mac/XXXXXXXXXX")];
> 
>          status = RtlStringCbPrintfA(Node,
>                                      sizeof (Node),
>                                      "mac/%u",
>                                      Index);
>          ASSERT(NT_SUCCESS(status));
> +        if (!NT_SUCCESS(status))
> +            continue;
> 
>          (VOID) XENBUS_STORE(Printf,
>                              &Mac->StoreInterface,
> --
> 2.16.2.windows.1
>