From 99b40610956a8a8755653a67392e2a8b772453be Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Mon, 27 Dec 2021 19:21:15 +0200 Subject: net: bridge: mcast: add and enforce query interval minimum As reported[1] if query interval is set too low and we have multiple bridges or even a single bridge with multiple querier vlans configured we can crash the machine. Add a 1 second minimum which must be enforced by overwriting the value if set lower (i.e. without returning an error) to avoid breaking user-space. If that happens a log message is emitted to let the administrator know that the interval has been set to the minimum. The issue has been present since these intervals could be user-controlled. [1] https://lore.kernel.org/netdev/e8b9ce41-57b9-b6e2-a46a-ff9c791cf0ba@gmail.com/ Fixes: d902eee43f19 ("bridge: Add multicast count/interval sysfs entries") Reported-by: Eric Dumazet Signed-off-by: Nikolay Aleksandrov Signed-off-by: Jakub Kicinski --- net/bridge/br_private.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net/bridge/br_private.h') diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index c0efd697865a..4ed7f11042e8 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -28,6 +28,7 @@ #define BR_MAX_PORTS (1<