From 9ddbcfa098bae757d3760dd1dbf2847a0bd5a525 Mon Sep 17 00:00:00 2001 From: Andy Grover Date: Fri, 17 Jul 2009 13:13:23 +0000 Subject: [PATCH] RDS/IB: Improve RDS protocol version checking RDS on IB uses privdata to do protocol version negotiation. Apparently the IB stack will return a larger privdata buffer than the struct we were expecting. Just to be extra-sure, this patch adds some checks in this area. Signed-off-by: Andy Grover Signed-off-by: David S. Miller --- net/rds/ib_cm.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/net/rds/ib_cm.c b/net/rds/ib_cm.c index 605c032ed5d5..0964ac533ec8 100644 --- a/net/rds/ib_cm.c +++ b/net/rds/ib_cm.c @@ -98,7 +98,7 @@ void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_even struct ib_qp_attr qp_attr; int err; - if (event->param.conn.private_data_len) { + if (event->param.conn.private_data_len >= sizeof(*dp)) { dp = event->param.conn.private_data; rds_ib_set_protocol(conn, @@ -344,19 +344,32 @@ out: return ret; } -static u32 rds_ib_protocol_compatible(const struct rds_ib_connect_private *dp) +static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event) { + const struct rds_ib_connect_private *dp = event->param.conn.private_data; u16 common; u32 version = 0; - /* rdma_cm private data is odd - when there is any private data in the + /* + * rdma_cm private data is odd - when there is any private data in the * request, we will be given a pretty large buffer without telling us the * original size. The only way to tell the difference is by looking at * the contents, which are initialized to zero. * If the protocol version fields aren't set, this is a connection attempt * from an older version. This could could be 3.0 or 2.0 - we can't tell. - * We really should have changed this for OFED 1.3 :-( */ - if (dp->dp_protocol_major == 0) + * We really should have changed this for OFED 1.3 :-( + */ + + /* Be paranoid. RDS always has privdata */ + if (!event->param.conn.private_data_len) { + printk(KERN_NOTICE "RDS incoming connection has no private data, " + "rejecting\n"); + return 0; + } + + /* Even if len is crap *now* I still want to check it. -ASG */ + if (event->param.conn.private_data_len < sizeof (*dp) + || dp->dp_protocol_major == 0) return RDS_PROTOCOL_3_0; common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS; @@ -388,7 +401,7 @@ int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id, int err, destroy = 1; /* Check whether the remote protocol version matches ours. */ - version = rds_ib_protocol_compatible(dp); + version = rds_ib_protocol_compatible(event); if (!version) goto out; -- 2.20.1