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 anyhow.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 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 22183f5360..ccf78b25e4 100644
--- a/hw/nvram/eeprom_at24c.c
+++ b/hw/nvram/eeprom_at24c.c
@@ -121,6 +121,11 @@ int at24c_eeprom_init(I2CSlave *i2c)
 {
     EEPROMState *ee = AT24C_EE(i2c);
 
+    if (!ee->rsize) {
+        ERR("rom-size not allowed to be 0\n");
+        exit(1);
+    }
+
     ee->mem = g_malloc0(ee->rsize);
 
     if (ee->blk) {
-- 
2.11.0

On 03/19/2018 10:30 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 anyhow.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  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 22183f5360..ccf78b25e4 100644
> --- a/hw/nvram/eeprom_at24c.c
> +++ b/hw/nvram/eeprom_at24c.c
> @@ -121,6 +121,11 @@ int at24c_eeprom_init(I2CSlave *i2c)
>  {
>      EEPROMState *ee = AT24C_EE(i2c);
>  
> +    if (!ee->rsize) {
> +        ERR("rom-size not allowed to be 0\n");

You can directly use error_report() in this patch.

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

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

> > +    if (!ee->rsize) {
> > +        ERR("rom-size not allowed to be 0\n");
> 
> You can directly use error_report() in this patch.

My reasoning was that this patch is suitable for stable while the
error_report() stuff is not. I neither wanted to mix those two here nor
did I want to make the stable-patch depend on the non-stable patch. So,
I chose to use ERR here and fix all of ERR later. OK?