From: Clay McClure Date: Fri, 22 Sep 2017 02:01:34 +0000 (-0700) Subject: ubi: Fix race condition between ubi volume creation and udev X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=7adc87b34aaf5df502f45e41f02089717b6f51c8;hp=bdd119a94b74acb4cc720695eac50f01173b7496 ubi: Fix race condition between ubi volume creation and udev commit a51a0c8d213594bc094cb8e54aad0cb6d7f7b9a6 upstream. Similar to commit 714fb87e8bc0 ("ubi: Fix race condition between ubi device creation and udev"), we should make the volume active before registering it. Signed-off-by: Clay McClure Signed-off-by: Richard Weinberger [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index 863835f4aefe..83ac8b43c4bd 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -312,6 +312,12 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) vol->last_eb_bytes = vol->usable_leb_size; } + /* Make volume "available" before it becomes accessible via sysfs */ + spin_lock(&ubi->volumes_lock); + ubi->volumes[vol_id] = vol; + ubi->vol_count += 1; + spin_unlock(&ubi->volumes_lock); + /* Register character device for the volume */ cdev_init(&vol->cdev, &ubi_vol_cdev_operations); vol->cdev.owner = THIS_MODULE; @@ -354,11 +360,6 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) if (err) goto out_sysfs; - spin_lock(&ubi->volumes_lock); - ubi->volumes[vol_id] = vol; - ubi->vol_count += 1; - spin_unlock(&ubi->volumes_lock); - ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED); if (paranoid_check_volumes(ubi)) dbg_err("check failed while creating volume %d", vol_id); @@ -379,6 +380,10 @@ out_sysfs: out_cdev: cdev_del(&vol->cdev); out_mapping: + spin_lock(&ubi->volumes_lock); + ubi->volumes[vol_id] = NULL; + ubi->vol_count -= 1; + spin_unlock(&ubi->volumes_lock); if (do_free) kfree(vol->eba_tbl); out_acc: