diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2018-09-10 14:00:53 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2018-12-16 22:09:23 +0000 |
| commit | 9d3a6c69c2e083f731f11a3849938a57c826c3f1 (patch) | |
| tree | e9956c603f6f1122b8a08b46db725f77be2671b2 | |
| parent | b8a864e3f5e949c0f36f6b60297fd620623f53e5 (diff) | |
USB: handle NULL config in usb_find_alt_setting()
commit c9a4cb204e9eb7fa7dfbe3f7d3a674fa530aa193 upstream.
usb_find_alt_setting() takes a pointer to a struct usb_host_config as
an argument; it searches for an interface with specified interface and
alternate setting numbers in that config. However, it crashes if the
usb_host_config pointer argument is NULL.
Since this is a general-purpose routine, available for use in many
places, we want to to be more robust. This patch makes it return NULL
whenever the config argument is NULL.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: syzbot+19c3aaef85a89d451eac@syzkaller.appspotmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | drivers/usb/core/usb.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index a92273026ecc..d885a07be4df 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -79,6 +79,8 @@ struct usb_host_interface *usb_find_alt_setting( struct usb_interface_cache *intf_cache = NULL; int i; + if (!config) + return NULL; for (i = 0; i < config->desc.bNumInterfaces; i++) { if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber == iface_num) { |