[PATCH] Fixed integer overflow in e1000e

[PATCH] Fixed integer overflow in e1000e

[andrew]

From: Andrew Melnychenko <andrew@daynix.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1737400
Fixed setting max_queue_num if there are no peers in NICConf. qemu_new_nic() creates NICState with 1 NetClientState(index 0) without peers, set max_queue_num to 0 - It prevents undefined behavior and possible crashes, especially during pcie hotplug.

Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
 hw/net/e1000e.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/net/e1000e.c b/hw/net/e1000e.c
index a91dbdca3c..f2cc1552c5 100644
--- a/hw/net/e1000e.c
+++ b/hw/net/e1000e.c
@@ -328,7 +328,7 @@ e1000e_init_net_peer(E1000EState *s, PCIDevice *pci_dev, uint8_t *macaddr)
     s->nic = qemu_new_nic(&net_e1000e_info, &s->conf,
         object_get_typename(OBJECT(s)), dev->id, s);
 
-    s->core.max_queue_num = s->conf.peers.queues - 1;
+    s->core.max_queue_num = s->conf.peers.queues ? s->conf.peers.queues - 1 : 0;
 
     trace_e1000e_mac_set_permanent(MAC_ARG(macaddr));
     memcpy(s->core.permanent_mac, macaddr, sizeof(s->core.permanent_mac));
-- 
2.24.1

Re: [PATCH] Fixed integer overflow in e1000e

[Philippe Mathieu-Daudé]

Hi Andrew,

Please Cc all the maintainers:

   ./scripts/get_maintainer.pl -f hw/net/e1000e.c
   Dmitry Fleytman <dmitry.fleytman@gmail.com> (maintainer:e1000e)
   Jason Wang <jasowang@redhat.com> (odd fixer:Network devices)
   qemu-devel@nongnu.org (open list:All patches CC here)

On 3/3/20 7:29 PM, andrew@daynix.com wrote:
> From: Andrew Melnychenko <andrew@daynix.com>
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1737400

The BZ backtrace lists e1000e_tx_pkt_send() which you fixes,
but you also fixes e1000e_start_recv(). Good.

Please include the BZ backtrace.

> Fixed setting max_queue_num if there are no peers in NICConf. qemu_new_nic() creates NICState with 1 NetClientState(index 0) without peers, set max_queue_num to 0 - It prevents undefined behavior and possible crashes, especially during pcie hotplug.
> 

Please add:

Cc: qemu-stable@nongnu.org
Fixes: 6f3fbe4ed06
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1737400

> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> ---
>   hw/net/e1000e.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/net/e1000e.c b/hw/net/e1000e.c
> index a91dbdca3c..f2cc1552c5 100644
> --- a/hw/net/e1000e.c
> +++ b/hw/net/e1000e.c
> @@ -328,7 +328,7 @@ e1000e_init_net_peer(E1000EState *s, PCIDevice *pci_dev, uint8_t *macaddr)
>       s->nic = qemu_new_nic(&net_e1000e_info, &s->conf,
>           object_get_typename(OBJECT(s)), dev->id, s);
>   
> -    s->core.max_queue_num = s->conf.peers.queues - 1;
> +    s->core.max_queue_num = s->conf.peers.queues ? s->conf.peers.queues - 1 : 0;
>   
>       trace_e1000e_mac_set_permanent(MAC_ARG(macaddr));
>       memcpy(s->core.permanent_mac, macaddr, sizeof(s->core.permanent_mac));
>