[PATCH v2 net] net: qrtr: make checks in qrtr_endpoint_post() stricter
From: Dan Carpenter <hidden>
Date: 2021-08-30 08:37:51
Also in:
linux-arm-msm
Subsystem:
networking [general], qualcomm ipc router (qrtr) driver, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Manivannan Sadhasivam, Linus Torvalds
These checks are still not strict enough. The main problem is that if
"cb->type == QRTR_TYPE_NEW_SERVER" is true then "len - hdrlen" is
guaranteed to be 4 but we need to be at least 16 bytes. In fact, we
can reject everything smaller than sizeof(*pkt) which is 20 bytes.
Also I don't like the ALIGN(size, 4). It's better to just insist that
data is needs to be aligned at the start.
Fixes: 0baa99ee353c ("net: qrtr: Allow non-immediate node routing")
Signed-off-by: Dan Carpenter <redacted>
---
v2: Fix a % vs & bug. Thanks, butt3rflyh4ck!
net/qrtr/qrtr.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
index b8508e35d20e..dbb647f5481b 100644
--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c@@ -493,7 +493,7 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len) goto err; } - if (!size || len != ALIGN(size, 4) + hdrlen) + if (!size || size & 3 || len != size + hdrlen) goto err; if (cb->dst_port != QRTR_PORT_CTRL && cb->type != QRTR_TYPE_DATA &&
@@ -506,8 +506,12 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len) if (cb->type == QRTR_TYPE_NEW_SERVER) { /* Remote node endpoint can bridge other distant nodes */ - const struct qrtr_ctrl_pkt *pkt = data + hdrlen; + const struct qrtr_ctrl_pkt *pkt; + if (size < sizeof(*pkt)) + goto err; + + pkt = data + hdrlen; qrtr_node_assign(node, le32_to_cpu(pkt->server.node)); }
--
2.20.1