diff options
| author | Guillaume Nault <g.nault@alphalink.fr> | 2020-05-22 00:57:28 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-05-27 16:40:31 +0200 |
| commit | df9fdbc23b7facbbaab468e7f3d8b7e6a10aaee1 (patch) | |
| tree | 8b4d529c8f750b8efd68663cb2ac9cc2d5ea289e /net/l2tp | |
| parent | f15f181bb2436fccca20c1034f0b9e71c729c62b (diff) | |
l2tp: initialise session's refcount before making it reachable
commit 9ee369a405c57613d7c83a3967780c3e30c52ecc upstream.
Sessions must be fully initialised before calling
l2tp_session_add_to_tunnel(). Otherwise, there's a short time frame
where partially initialised sessions can be accessed by external users.
Backporting Notes
l2tp_core.c: moving code that had been converted from atomic to
refcount_t by an earlier change (which isn't being included in this
patch series).
Fixes: dbdbc73b4478 ("l2tp: fix duplicate session creation")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/l2tp')
| -rw-r--r-- | net/l2tp/l2tp_core.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 7e593e399774..c0abd5efd824 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -1853,6 +1853,8 @@ struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunn l2tp_session_set_header_len(session, tunnel->version); + l2tp_session_inc_refcount(session); + err = l2tp_session_add_to_tunnel(tunnel, session); if (err) { kfree(session); @@ -1860,10 +1862,6 @@ struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunn return ERR_PTR(err); } - /* Bump the reference count. The session context is deleted - * only when this drops to zero. - */ - l2tp_session_inc_refcount(session); l2tp_tunnel_inc_refcount(tunnel); /* Ensure tunnel socket isn't deleted */ |