From c62e7ac395641a764639b1c6635955f02b8d9d16 Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Wed, 15 Jul 2020 09:41:18 +0200 Subject: [PATCH] net: genetlink: Move initialization to core_initcall The generic netlink is initialized far after the netlink protocol itself at subsys_initcall. The devlink is initialized at the same level, but after, as shown by a disassembly of the vmlinux: [ ... ] 374 ffff8000115f22c0 <__initcall_devlink_init4>: 375 ffff8000115f22c4 <__initcall_genl_init4>: [ ... ] The function devlink_init() calls genl_register_family() before the generic netlink subsystem is initialized. As the generic netlink initcall level is set since 2005, it seems that was not a problem, but now we have the thermal framework initialized at the core_initcall level which creates the generic netlink family and sends a notification which leads to a subtle memory corruption only detectable when the CONFIG_INIT_ON_ALLOC_DEFAULT_ON option is set with the earlycon at init time. The thermal framework needs to be initialized early in order to begin the mitigation as soon as possible. Moving it to postcore_initcall is acceptable. This patch changes the initialization level for the generic netlink family to the core_initcall and comes after the netlink protocol initialization. Signed-off-by: Daniel Lezcano Acked-by: David S. Miller Tested-by: Marek Szyprowski Reviewed-by: Amit Kucheria Link: https://lore.kernel.org/r/20200715074120.8768-1-daniel.lezcano@linaro.org --- net/netlink/genetlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 55ee680e9db1..36b8a1909826 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1263,7 +1263,7 @@ static int __init genl_init(void) panic("GENL: Cannot register controller: %d\n", err); } -subsys_initcall(genl_init); +core_initcall(genl_init); static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, gfp_t flags)