| From foo@baz Sun Nov 22 12:00:04 PM CET 2020 |
| From: Xie He <xie.he.0141@gmail.com> |
| Date: Thu, 12 Nov 2020 02:35:06 -0800 |
| Subject: net: x25: Increase refcnt of "struct x25_neigh" in x25_rx_call_request |
| |
| From: Xie He <xie.he.0141@gmail.com> |
| |
| [ Upstream commit 4ee18c179e5e815fa5575e0d2db0c05795a804ee ] |
| |
| The x25_disconnect function in x25_subr.c would decrease the refcount of |
| "x25->neighbour" (struct x25_neigh) and reset this pointer to NULL. |
| |
| However, the x25_rx_call_request function in af_x25.c, which is called |
| when we receive a connection request, does not increase the refcount when |
| it assigns the pointer. |
| |
| Fix this issue by increasing the refcount of "struct x25_neigh" in |
| x25_rx_call_request. |
| |
| This patch fixes frequent kernel crashes when using AF_X25 sockets. |
| |
| Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect") |
| Cc: Martin Schiller <ms@dev.tdt.de> |
| Signed-off-by: Xie He <xie.he.0141@gmail.com> |
| Link: https://lore.kernel.org/r/20201112103506.5875-1-xie.he.0141@gmail.com |
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/x25/af_x25.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| --- a/net/x25/af_x25.c |
| +++ b/net/x25/af_x25.c |
| @@ -1049,6 +1049,7 @@ int x25_rx_call_request(struct sk_buff * |
| makex25->lci = lci; |
| makex25->dest_addr = dest_addr; |
| makex25->source_addr = source_addr; |
| + x25_neigh_hold(nb); |
| makex25->neighbour = nb; |
| makex25->facilities = facilities; |
| makex25->dte_facilities= dte_facilities; |
