Messages in this thread | | | Subject | Re: [PATCH] scsi: bsg: Fix device unregistration | From | Zenghui Yu <> | Date | Sat, 11 Sep 2021 09:41:03 +0800 |
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On 2021/9/10 20:45, Johan Hovold wrote: > On Thu, Sep 09, 2021 at 11:46:08AM +0800, Zenghui Yu wrote:
>> @@ -218,6 +226,7 @@ struct bsg_device *bsg_register_queue(struct request_queue *q, >> out_device_del: >> cdev_device_del(&bd->cdev, &bd->device); >> out_ida_remove: >> + put_device(&bd->device); >> ida_simple_remove(&bsg_minor_ida, MINOR(bd->device.devt)); >> out_kfree: >> kfree(bd); > > Ehh, what about the blatant use-after-free and double-free you just > added here?
Yeah, whoops. That's definitely wrong. I'm squash the following fix in this patch.
Thanks for the heads up!
|diff --git a/block/bsg.c b/block/bsg.c |index c3bb92b9af7e..882f56bff14f 100644 |--- a/block/bsg.c |+++ b/block/bsg.c |@@ -200,7 +200,8 @@ struct bsg_device *bsg_register_queue(struct request_queue *q, | if (ret < 0) { | if (ret == -ENOSPC) | dev_err(parent, "bsg: too many bsg devices\n"); |- goto out_kfree; |+ kfree(bd); |+ return ERR_PTR(ret); | } | bd->device.devt = MKDEV(bsg_major, ret); | bd->device.class = bsg_class; |@@ -213,7 +214,7 @@ struct bsg_device *bsg_register_queue(struct request_queue *q, | bd->cdev.owner = THIS_MODULE; | ret = cdev_device_add(&bd->cdev, &bd->device); | if (ret) |- goto out_ida_remove; |+ goto out_put_device; | | if (q->kobj.sd) { | ret = sysfs_create_link(&q->kobj, &bd->device.kobj, "bsg"); |@@ -225,11 +226,8 @@ struct bsg_device *bsg_register_queue(struct request_queue *q, | | out_device_del: | cdev_device_del(&bd->cdev, &bd->device); |-out_ida_remove: |+out_put_device: | put_device(&bd->device); |- ida_simple_remove(&bsg_minor_ida, MINOR(bd->device.devt)); |-out_kfree: |- kfree(bd); | return ERR_PTR(ret); | } | EXPORT_SYMBOL_GPL(bsg_register_queue);
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