net: hsr: prevent NULL pointer dereference in hsr_proxy_announce()

In the function hsr_proxy_annouance() added in the previous commit
5f703ce5c9 ("net: hsr: Send supervisory frames to HSR network
with ProxyNodeTable data"), the return value of the hsr_port_get_hsr()
function is not checked to be a NULL pointer, which causes a NULL
pointer dereference.

To solve this, we need to add code to check whether the return value
of hsr_port_get_hsr() is NULL.

Reported-by: syzbot+02a42d9b1bd395cbcab4@syzkaller.appspotmail.com
Fixes: 5f703ce5c9 ("net: hsr: Send supervisory frames to HSR network with ProxyNodeTable data")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Lukasz Majewski <lukma@denx.de>
Link: https://patch.msgid.link/20240907190341.162289-1-aha310510@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jeongjun Park 2024-09-08 04:03:41 +09:00 committed by Jakub Kicinski
parent 6254031777
commit a7789fd4ca

View File

@ -414,6 +414,9 @@ static void hsr_proxy_announce(struct timer_list *t)
* of SAN nodes stored in ProxyNodeTable.
*/
interlink = hsr_port_get_hsr(hsr, HSR_PT_INTERLINK);
if (!interlink)
goto done;
list_for_each_entry_rcu(node, &hsr->proxy_node_db, mac_list) {
if (hsr_addr_is_redbox(hsr, node->macaddress_A))
continue;
@ -428,6 +431,7 @@ static void hsr_proxy_announce(struct timer_list *t)
mod_timer(&hsr->announce_proxy_timer, jiffies + interval);
}
done:
rcu_read_unlock();
}