memstick: avert possible race condition between idr_pre_get and idr_get_new

[pandora-kernel.git] / drivers / memstick / core / mspro_block.c

diff --git a/drivers/memstick/core/mspro_block.c b/drivers/memstick/core/mspro_block.c
index 02362ec..a167938 100644 (file)
--- a/drivers/memstick/core/mspro_block.c
+++ b/drivers/memstick/core/mspro_block.c
@@ -1206,10 +1206,12 @@ static int mspro_block_init_disk(struct memstick_dev *card)
 
        msb->page_size = be16_to_cpu(sys_info->unit_size);
 
-       if (!idr_pre_get(&mspro_block_disk_idr, GFP_KERNEL))
+       mutex_lock(&mspro_block_disk_lock);
+       if (!idr_pre_get(&mspro_block_disk_idr, GFP_KERNEL)) {
+               mutex_unlock(&mspro_block_disk_lock);
                return -ENOMEM;
+       }
 
-       mutex_lock(&mspro_block_disk_lock);
        rc = idr_get_new(&mspro_block_disk_idr, card, &disk_id);
        mutex_unlock(&mspro_block_disk_lock);