[PATCH AUTOSEL 4.19 1/3] tty: vcc: Add check for kstrdup() in vcc_probe()

From: Sasha Levin
Date: Tue Nov 07 2023 - 18:29:11 EST


From: Yi Yang <yiyang13@xxxxxxxxxx>

[ Upstream commit d81ffb87aaa75f842cd7aa57091810353755b3e6 ]

Add check for the return value of kstrdup() and return the error, if it
fails in order to avoid NULL pointer dereference.

Signed-off-by: Yi Yang <yiyang13@xxxxxxxxxx>
Reviewed-by: Jiri Slaby <jirislaby@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230904035220.48164-1-yiyang13@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/tty/vcc.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/vcc.c b/drivers/tty/vcc.c
index 10a832a2135e2..31ecba1133159 100644
--- a/drivers/tty/vcc.c
+++ b/drivers/tty/vcc.c
@@ -586,18 +586,22 @@ static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
return -ENOMEM;

name = kstrdup(dev_name(&vdev->dev), GFP_KERNEL);
+ if (!name) {
+ rv = -ENOMEM;
+ goto free_port;
+ }

rv = vio_driver_init(&port->vio, vdev, VDEV_CONSOLE_CON, vcc_versions,
ARRAY_SIZE(vcc_versions), NULL, name);
if (rv)
- goto free_port;
+ goto free_name;

port->vio.debug = vcc_dbg_vio;
vcc_ldc_cfg.debug = vcc_dbg_ldc;

rv = vio_ldc_alloc(&port->vio, &vcc_ldc_cfg, port);
if (rv)
- goto free_port;
+ goto free_name;

spin_lock_init(&port->lock);

@@ -631,6 +635,11 @@ static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
goto unreg_tty;
}
port->domain = kstrdup(domain, GFP_KERNEL);
+ if (!port->domain) {
+ rv = -ENOMEM;
+ goto unreg_tty;
+ }
+

mdesc_release(hp);

@@ -660,8 +669,9 @@ static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
vcc_table_remove(port->index);
free_ldc:
vio_ldc_free(&port->vio);
-free_port:
+free_name:
kfree(name);
+free_port:
kfree(port);

return rv;
--
2.42.0