dev->config and dev->hs_config and dev->dev need to be cleaned if
dev_config fails to avoid UAF.
Acked-by: Alan Stern <[email protected]>
Signed-off-by: Hangyu Hua <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Cc: [email protected] #4.4+
---
drivers/usb/gadget/legacy/inode.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
index eaad03c0252f..25c8809e0a38 100644
--- a/drivers/usb/gadget/legacy/inode.c
+++ b/drivers/usb/gadget/legacy/inode.c
@@ -1875,8 +1875,8 @@ dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
value = usb_gadget_probe_driver(&gadgetfs_driver);
if (value != 0) {
- kfree (dev->buf);
- dev->buf = NULL;
+ spin_lock_irq(&dev->lock);
+ goto fail;
} else {
/* at this point "good" hardware has for the first time
* let the USB the host see us. alternatively, if users
@@ -1893,6 +1893,9 @@ dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
return value;
fail:
+ dev->config = NULL;
+ dev->hs_config = NULL;
+ dev->dev = NULL;
spin_unlock_irq (&dev->lock);
pr_debug ("%s: %s fail %zd, %p\n", shortname, __func__, value, dev);
kfree (dev->buf);
--
2.25.1