Re: [PATCH v2 3/3] hw/smbios: add an assertion to ensure tables 19 and 32 do not collide

[Igor Mammedov]

On Mon,  7 Feb 2022 17:01:29 +0530
Ani Sinha <ani@anisinha.ca> wrote:

> Since change b3cddba9c14b034 ("hw/smbios: fix table memory corruption with 
> large memory vms")
> we reserve additional memory space between tables 17 and 19 for large VMs.
> This may cause table 19 to collide with table 32 for those VMs. This change
> adds an assertion to make sure table 19 does not extend into the memory used
> by table 32.
> 
> Signed-off-by: Ani Sinha <ani@anisinha.ca>
> ---
>  hw/smbios/smbios.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/hw/smbios/smbios.c b/hw/smbios/smbios.c
> index d7de740363..800a35e9a5 100644
> --- a/hw/smbios/smbios.c
> +++ b/hw/smbios/smbios.c
> @@ -1048,6 +1048,9 @@ void smbios_get_tables(MachineState *ms,
>                                         mem_array[i].length);
>          }
>  
> +        /* we need to make sure table 19 and table 32 do not overlap */
same as in 2/3 (here and commit message), tables do not overlap

> +        assert((mem_array_size + offset) < (T32_BASE - T19_BASE));
> +
>          smbios_build_type_32_table();
>          smbios_build_type_38_table();
>          smbios_build_type_41_table(errp);