[PATCH 5.15 025/247] rpmsg: virtio: Fix possible double free in rpmsg_probe()

From: Greg Kroah-Hartman
Date: Mon Jun 13 2022 - 09:00:40 EST


From: Hangyu Hua <hbh25y@xxxxxxxxx>

[ Upstream commit c2eecefec5df1306eafce28ccdf1ca159a552ecc ]

vch will be free in virtio_rpmsg_release_device() when
rpmsg_ns_register_device() fails. There is no need to call kfree() again.

Fix this by changing error path from free_vch to free_ctrldev.

Fixes: c486682ae1e2 ("rpmsg: virtio: Register the rpmsg_char device")
Signed-off-by: Hangyu Hua <hbh25y@xxxxxxxxx>
Tested-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220426060536.15594-2-hbh25y@xxxxxxxxx
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/rpmsg/virtio_rpmsg_bus.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 8e49a3bacfc7..834a0811e371 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -964,7 +964,8 @@ static int rpmsg_probe(struct virtio_device *vdev)

err = rpmsg_ns_register_device(rpdev_ns);
if (err)
- goto free_vch;
+ /* vch will be free in virtio_rpmsg_release_device() */
+ goto free_ctrldev;
}

/*
@@ -988,8 +989,6 @@ static int rpmsg_probe(struct virtio_device *vdev)

return 0;

-free_vch:
- kfree(vch);
free_ctrldev:
rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
free_coherent:
--
2.35.1