diff options
| author | Sabrina Dubroca <sd@queasysnail.net> | 2018-08-28 13:40:53 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-08-29 19:28:55 -0700 |
| commit | f707ef61e17261f2bb18c3e4871c6f135ab3aba9 (patch) | |
| tree | 45c00ac0e6e8a7daaf4f47761d6f6f355271d815 | |
| parent | a03dc36bdca6b614651fedfcd8559cf914d2d21d (diff) | |
net: rtnl: return early from rtnl_unregister_all when protocol isn't registered
rtnl_unregister_all(PF_INET6) gets called from inet6_init in cases when
no handler has been registered for PF_INET6 yet, for example if
ip6_mr_init() fails. Abort and avoid a NULL pointer deref in that case.
Example of panic (triggered by faking a failure of
register_pernet_subsys):
general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI
[...]
RIP: 0010:rtnl_unregister_all+0x17e/0x2a0
[...]
Call Trace:
? rtnetlink_net_init+0x250/0x250
? sock_unregister+0x103/0x160
? kernel_getsockopt+0x200/0x200
inet6_init+0x197/0x20d
Fixes: e2fddf5e96df ("[IPV6]: Make af_inet6 to check ip6_route_init return value.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/rtnetlink.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 24431e578310..60c928894a78 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -324,6 +324,10 @@ void rtnl_unregister_all(int protocol) rtnl_lock(); tab = rtnl_msg_handlers[protocol]; + if (!tab) { + rtnl_unlock(); + return; + } RCU_INIT_POINTER(rtnl_msg_handlers[protocol], NULL); for (msgindex = 0; msgindex < RTM_NR_MSGTYPES; msgindex++) { link = tab[msgindex]; |