From: Michal Nazarewicz <m.nazarewicz@xxxxxxxxxxx> During __gfs_do_config() some invalid pointers may be left in usb_configuration::interfaces array from previous calls to the __gfs_do_config() for the same configuration. This will always happen if an user space function which has a fewer then the last user space function registers itself. Composite's set_config() function that a pointer after the last interface in usb_configuration::interface is NULL unless the array is full. This patch makes the __gfs_do_config() make sure that if the usb_configuration::interface is not full then a pointer after the last interface is NULL. Signed-off-by: Michal Nazarewicz <m.nazarewicz@xxxxxxxxxxx> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx> --- drivers/usb/gadget/g_ffs.c | 11 +++++++++++ 1 files changed, 11 insertions(+), 0 deletions(-) diff --git a/drivers/usb/gadget/g_ffs.c b/drivers/usb/gadget/g_ffs.c index 4b0e4a0..d1af253 100644 --- a/drivers/usb/gadget/g_ffs.c +++ b/drivers/usb/gadget/g_ffs.c @@ -392,6 +392,17 @@ static int __gfs_do_config(struct usb_configuration *c, if (unlikely(ret < 0)) return ret; + /* After previous do_configs there may be some invalid + * pointers in c->interface array. This happens every time + * a user space function with fewer interfaces than a user + * space function that was run before the new one is run. The + * compasit's set_config() assumes that if there is no more + * then MAX_CONFIG_INTERFACES interfaces in a configuration + * then there is a NULL pointer after the last interface in + * c->interface array. We need to make sure this is true. */ + if (c->next_interface_id < ARRAY_SIZE(c->interface)) + c->interface[c->next_interface_id] = NULL; + return 0; } -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
