From: Masahiro Yamada masahiroy@kernel.org
[ Upstream commit 5801f064e35181c71857a80ff18af4dbec3c5f5c ]
EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic.
modpost used to detect it, but it has been broken for a decade.
Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds.
There are two ways to fix it:
- Remove __init - Remove EXPORT_SYMBOL
I chose the latter for this case because the caller (net/ipv6/seg6.c) and the callee (net/ipv6/seg6_hmac.c) belong to the same module. It seems an internal function call in ipv6.ko.
Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support") Reported-by: Stephen Rothwell sfr@canb.auug.org.au Signed-off-by: Masahiro Yamada masahiroy@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv6/seg6_hmac.c | 1 - 1 file changed, 1 deletion(-)
diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c index ffcfcd2b128f..a4cad71c4204 100644 --- a/net/ipv6/seg6_hmac.c +++ b/net/ipv6/seg6_hmac.c @@ -401,7 +401,6 @@ int __init seg6_hmac_init(void) { return seg6_hmac_init_algo(); } -EXPORT_SYMBOL(seg6_hmac_init);
int __net_init seg6_hmac_net_init(struct net *net) {