Commit d333503d authored Aug 01, 2021 by Xin Long Committed by Greg Kroah-Hartman Aug 12, 2021

sctp: move the active_key update after sh_keys is added



[ Upstream commit ae954bbc451d267f7d60d7b49db811d5a68ebd7b ]

In commit 58acd1009226 ("sctp: update active_key for asoc when old key is
being replaced"), sctp_auth_asoc_init_active_key() is called to update
the active_key right after the old key is deleted and before the new key
is added, and it caused that the active_key could be found with the key_id.

In Ying Xu's testing, the BUG_ON in sctp_auth_asoc_init_active_key() was
triggered:

  [ ] kernel BUG at net/sctp/auth.c:416!
  [ ] RIP: 0010:sctp_auth_asoc_init_active_key.part.8+0xe7/0xf0 [sctp]
  [ ] Call Trace:
  [ ]  sctp_auth_set_key+0x16d/0x1b0 [sctp]
  [ ]  sctp_setsockopt.part.33+0x1ba9/0x2bd0 [sctp]
  [ ]  __sys_setsockopt+0xd6/0x1d0
  [ ]  __x64_sys_setsockopt+0x20/0x30
  [ ]  do_syscall_64+0x5b/0x1a0

So fix it by moving the active_key update after sh_keys is added.

Fixes: 58acd1009226 ("sctp: update active_key for asoc when old key is being replaced")
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent de30346d

net/sctp/auth.c

+9 −5

Original line number	Diff line number	Diff line
		@@ -863,13 +863,17 @@ int sctp_auth_set_key(struct sctp_endpoint *ep,
		memcpy(key->data, &auth_key->sca_key[0], auth_key->sca_keylength);
		cur_key->key = key;

		if (replace) {
		if (!replace) {
		list_add(&cur_key->key_list, sh_keys);
		return 0;
		}

		list_del_init(&shkey->key_list);
		sctp_auth_shkey_release(shkey);
		list_add(&cur_key->key_list, sh_keys);

		if (asoc && asoc->active_key_id == auth_key->sca_keynumber)
		sctp_auth_asoc_init_active_key(asoc, GFP_KERNEL);
		}
		list_add(&cur_key->key_list, sh_keys);

		return 0;
		}