aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorXin Long <lucien.xin@gmail.com>2019-03-03 17:54:55 +0800
committerDavid S. Miller <davem@davemloft.net>2019-03-08 11:42:49 -0800
commitc6f33e05225696fee3c901b7526b80f31848454e (patch)
tree9a26e6e05b1d2d57672843e37418ff0d17c9fd0d
parentsctp: move up sctp_auth_init_hmacs() in sctp_endpoint_init() (diff)
downloadlinux-dev-c6f33e05225696fee3c901b7526b80f31848454e.tar.xz
linux-dev-c6f33e05225696fee3c901b7526b80f31848454e.zip
sctp: call sctp_auth_init_hmacs() in sctp_sock_migrate()
New ep's auth_hmacs should be set if old ep's is set, in case that net->sctp.auth_enable has been changed to 0 by users and new ep's auth_hmacs couldn't be set in sctp_endpoint_init(). It can even crash kernel by doing: 1. on server: sysctl -w net.sctp.auth_enable=1, sysctl -w net.sctp.addip_enable=1, sysctl -w net.sctp.addip_noauth_enable=0, listen() on server, sysctl -w net.sctp.auth_enable=0. 2. on client: connect() to server. 3. on server: accept() the asoc, sysctl -w net.sctp.auth_enable=1. 4. on client: send() asconf packet to server. The call trace: [ 245.280251] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 245.286872] RIP: 0010:sctp_auth_calculate_hmac+0xa3/0x140 [sctp] [ 245.304572] Call Trace: [ 245.305091] <IRQ> [ 245.311287] sctp_sf_authenticate+0x110/0x160 [sctp] [ 245.312311] sctp_sf_eat_auth+0xf2/0x230 [sctp] [ 245.313249] sctp_do_sm+0x9a/0x2d0 [sctp] [ 245.321483] sctp_assoc_bh_rcv+0xed/0x1a0 [sctp] [ 245.322495] sctp_rcv+0xa66/0xc70 [sctp] It's because the old ep->auth_hmacs wasn't copied to the new ep while ep->auth_hmacs is used in sctp_auth_calculate_hmac() when processing the incoming auth chunks, and it should have been done when migrating sock. Reported-by: Ying Xu <yinxu@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
-rw-r--r--net/sctp/socket.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 44f2acb3d433..6140471efd4b 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -9225,6 +9225,16 @@ static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
if (err)
return err;
+ /* New ep's auth_hmacs should be set if old ep's is set, in case
+ * that net->sctp.auth_enable has been changed to 0 by users and
+ * new ep's auth_hmacs couldn't be set in sctp_endpoint_init().
+ */
+ if (oldsp->ep->auth_hmacs) {
+ err = sctp_auth_init_hmacs(newsp->ep, GFP_KERNEL);
+ if (err)
+ return err;
+ }
+
/* Move any messages in the old socket's receive queue that are for the
* peeled off association to the new socket's receive queue.
*/