Re: [Qemu-devel] [PATCH 2/3] nvram: at24c: prevent segfault by checking "rom-size"

[Philippe Mathieu-Daudé <f4bug@xxxxxxxxx>]

On 03/12/2018 10:42 PM, Wolfram Sang wrote:
> The value for "rom-size" is used as a divisor, so it must not be 0 or it
> will segfault. A size of 0 wouldn't make sense as well.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
>  hw/nvram/eeprom_at24c.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c
> index 8507516b7e..d82710e1df 100644
> --- a/hw/nvram/eeprom_at24c.c
> +++ b/hw/nvram/eeprom_at24c.c
> @@ -120,6 +120,11 @@ int at24c_eeprom_init(I2CSlave *i2c)
>  {
>      EEPROMState *ee = AT24C_EE(i2c);
>  
> +    if (!ee->rsize) {
> +        ERR("rom-size not allowed to be 0\n");

This might be more useful:

           error_report("Minimum rom-size is %u", AT24C_ROMSIZE_MIN);

> +        exit(1);
> +    }
> +
>      ee->mem = g_malloc0(ee->rsize);
>  
>      if (ee->blk) {
>