From: Hangyu Hua Date: Fri, 31 Dec 2021 17:21:38 +0000 (+0800) Subject: usb: gadget: clear related members when goto fail X-Git-Tag: block-5.17-2022-01-21~30^2~14 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=501e38a5531efbd77d5c73c0ba838a889bfc1d74;p=linux-block.git usb: gadget: clear related members when goto fail dev->config and dev->hs_config and dev->dev need to be cleaned if dev_config fails to avoid UAF. Acked-by: Alan Stern Signed-off-by: Hangyu Hua Link: https://lore.kernel.org/r/20211231172138.7993-3-hbh25y@gmail.com Signed-off-by: Greg Kroah-Hartman --- 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);