From 04ded1672402577cd3f390c764f3046cc704a42a Mon Sep 17 00:00:00 2001 From: Sean Hefty Date: Tue, 6 Dec 2011 21:17:11 +0000 Subject: [PATCH] RDMA/cma: Verify private data length private_data_len is defined as a u8. If the user specifies a large private_data size (> 220 bytes), we will calculate a total length that exceeds 255, resulting in private_data_len wrapping back to 0. This can lead to overwriting random kernel memory. Avoid this by verifying that the resulting size fits into a u8. Reported-by: B. Thery Addresses: Signed-off-by: Sean Hefty Signed-off-by: Roland Dreier --- drivers/infiniband/core/cma.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index 75ff821c0af0..d0d4aa9f4802 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -2513,6 +2513,9 @@ static int cma_resolve_ib_udp(struct rdma_id_private *id_priv, req.private_data_len = sizeof(struct cma_hdr) + conn_param->private_data_len; + if (req.private_data_len < conn_param->private_data_len) + return -EINVAL; + req.private_data = kzalloc(req.private_data_len, GFP_ATOMIC); if (!req.private_data) return -ENOMEM; @@ -2562,6 +2565,9 @@ static int cma_connect_ib(struct rdma_id_private *id_priv, memset(&req, 0, sizeof req); offset = cma_user_data_offset(id_priv->id.ps); req.private_data_len = offset + conn_param->private_data_len; + if (req.private_data_len < conn_param->private_data_len) + return -EINVAL; + private_data = kzalloc(req.private_data_len, GFP_ATOMIC); if (!private_data) return -ENOMEM; -- 2.20.1