[PATCH 6.0 0510/1073] net: vmw_vsock: vmci: Check memcpy_from_msg()

Greg Kroah-Hartman
2022-12-28T16:02:29Z

From: Artem Chernyshev <artem.chernyshev@red-soft.ru>

[ Upstream commit 44aa5a6dba8283bfda28b1517af4de711c5652a4 ]

vmci_transport_dgram_enqueue() does not check the return value
of memcpy_from_msg(). If memcpy_from_msg() fails, it is possible that
uninitialized memory contents are sent unintentionally instead of user's
message in the datagram to the destination. Return with an error if
memcpy_from_msg() fails.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 0f7db23a07af ("vmci_transport: switch ->enqeue_dgram, ->enqueue_stream and ->dequeue_stream to msghdr")
Signed-off-by: Artem Chernyshev <artem.chernyshev@red-soft.ru>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/vmw_vsock/vmci_transport.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
index b14f0ed7427b..a794e8b01136 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c
@@ -1711,7 +1711,11 @@ static int vmci_transport_dgram_enqueue(
if (!dg)
return -ENOMEM;

- memcpy_from_msg(VMCI_DG_PAYLOAD(dg), msg, len);
+ err = memcpy_from_msg(VMCI_DG_PAYLOAD(dg), msg, len);
+ if (err) {
+ kfree(dg);
+ return err;
+ }

dg->dst = vmci_make_handle(remote_addr->svm_cid,
remote_addr->svm_port);
--
2.35.1