From 7fa24a821af13e4cf468e9c9e2cfeae6b71832d3 Mon Sep 17 00:00:00 2001 From: Rui Miguel Silva Date: Wed, 20 May 2015 14:52:40 +0100 Subject: [PATCH] usb: gadget: f_fs: add extra check before unregister_gadget_item commit f14e9ad17f46051b02bffffac2036486097de19e upstream. ffs_closed can race with configfs_rmdir which will call config_item_release, so add an extra check to avoid calling the unregister_gadget_item with an null gadget item. Signed-off-by: Rui Miguel Silva Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_fs.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 3e53df4ab1eb..ce3b40734a86 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -3433,6 +3433,7 @@ static int ffs_ready(struct ffs_data *ffs) static void ffs_closed(struct ffs_data *ffs) { struct ffs_dev *ffs_obj; + struct f_fs_opts *opts; ENTER(); ffs_dev_lock(); @@ -3446,8 +3447,13 @@ static void ffs_closed(struct ffs_data *ffs) if (ffs_obj->ffs_closed_callback) ffs_obj->ffs_closed_callback(ffs); - if (!ffs_obj->opts || ffs_obj->opts->no_configfs - || !ffs_obj->opts->func_inst.group.cg_item.ci_parent) + if (ffs_obj->opts) + opts = ffs_obj->opts; + else + goto done; + + if (opts->no_configfs || !opts->func_inst.group.cg_item.ci_parent + || !atomic_read(&opts->func_inst.group.cg_item.ci_kref.refcount)) goto done; unregister_gadget_item(ffs_obj->opts-> -- 2.43.0