From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 30 Jun 2020 14:46:15 +0300
Subject: net: qrtr: Fix an out of bounds read qrtr_endpoint_post()
Git-commit: 8ff41cc21714704ef0158a546c3c4d07fae2c952
Patch-mainline: 5.8-rc5
References: networking-stable-20_07_17
This code assumes that the user passed in enough data for a
qrtr_hdr_v1 or qrtr_hdr_v2 struct, but it's not necessarily true. If
the buffer is too small then it will read beyond the end.
Reported-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reported-by: syzbot+b8fe393f999a291a9ea6@syzkaller.appspotmail.com
Fixes: 194ccc88297a ("net: qrtr: Support decoding incoming v2 packets")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
net/qrtr/qrtr.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c
@@ -259,7 +259,7 @@ int qrtr_endpoint_post(struct qrtr_endpo
unsigned int ver;
size_t hdrlen;
- if (len & 3)
+ if (len == 0 || len & 3)
return -EINVAL;
skb = netdev_alloc_skb(NULL, len);
@@ -273,6 +273,8 @@ int qrtr_endpoint_post(struct qrtr_endpo
switch (ver) {
case QRTR_PROTO_VER_1:
+ if (len < sizeof(*v1))
+ goto err;
v1 = data;
hdrlen = sizeof(*v1);
@@ -286,6 +288,8 @@ int qrtr_endpoint_post(struct qrtr_endpo
size = le32_to_cpu(v1->size);
break;
case QRTR_PROTO_VER_2:
+ if (len < sizeof(*v2))
+ goto err;
v2 = data;
hdrlen = sizeof(*v2) + v2->optlen;