From: Xiaolong Huang
stable inclusion
from linux-4.19.206
commit ce7d8be2eaa4cab3032e256d154d1c33843d2367
category: bugfix
issue: #I4CC5E
CVE: CVE-2021-3743
--------------------------------
commit 7e78c597c3ebfd0cb329aa09a838734147e4f117 upstream.
This check was incomplete, did not consider size is 0:
if (len != ALIGN(size, 4) + hdrlen)
goto err;
if size from qrtr_hdr is 0, the result of ALIGN(size, 4)
will be 0, In case of len == hdrlen and size == 0
in header this check won't fail and
if (cb->type == QRTR_TYPE_NEW_SERVER) {
/* Remote node endpoint can bridge other distant nodes */
const struct qrtr_ctrl_pkt *pkt = data + hdrlen;
qrtr_node_assign(node, le32_to_cpu(pkt->server.node));
}
will also read out of bound from data, which is hdrlen allocated block.
Fixes: 194ccc88297a ("net: qrtr: Support decoding incoming v2 packets")
Fixes: ad9d24c9429e ("net: qrtr: fix OOB Read in qrtr_endpoint_post")
Signed-off-by: Xiaolong Huang
Signed-off-by: David S. Miller
Signed-off-by: Greg Kroah-Hartman
Signed-off-by: Yang Yingliang
Reviewed-by: Xiu Jianfeng
Reviewed-by: Yue Haibing
Signed-off-by: Yang Yingliang
Signed-off-by: Yu Changchun
---
net/qrtr/qrtr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
index 4c7ae7155078..05e7414438c9 100644
--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c
@@ -321,7 +321,7 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
goto err;
}
- if (len != ALIGN(size, 4) + hdrlen)
+ if (!size || len != ALIGN(size, 4) + hdrlen)
goto err;
if (cb->dst_port != QRTR_PORT_CTRL && cb->type != QRTR_TYPE_DATA)
--
2.22.0
