| Message ID | 20231208071317.1268465-1-linan666@huaweicloud.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ubi: block: fix null-pointer-dereference in ubiblock_create() | expand |
在 2023/12/8 15:13, linan666@huaweicloud.com 写道: > From: Li Nan <linan122@huawei.com> > > If idr_alloc() fails, dev->gd will be put after goto out_cleanup_disk in > ubiblock_create(), but dev->gd has not been assigned yet at this time, and > accessing it will trigger a null-pointer-dereference issue. Fix it by put > gd directly. Function 'put_disk()' checks disk whether is NULL, so I think it's a 'memleak' problem, not a null-ptr-deref problem. > > Signed-off-by: Li Nan <linan122@huawei.com> > --- > drivers/mtd/ubi/block.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c > index 309a42aeaa4c..654bd7372cd8 100644 > --- a/drivers/mtd/ubi/block.c > +++ b/drivers/mtd/ubi/block.c > @@ -434,7 +434,7 @@ int ubiblock_create(struct ubi_volume_info *vi) > list_del(&dev->list); > idr_remove(&ubiblock_minor_idr, gd->first_minor); > out_cleanup_disk: > - put_disk(dev->gd); > + put_disk(gd); For memleak solution: Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com> > out_free_tags: > blk_mq_free_tag_set(&dev->tag_set); > out_free_dev:
在 2023/12/8 15:29, Zhihao Cheng 写道: > 在 2023/12/8 15:13, linan666@huaweicloud.com 写道: >> From: Li Nan <linan122@huawei.com> >> >> If idr_alloc() fails, dev->gd will be put after goto out_cleanup_disk in >> ubiblock_create(), but dev->gd has not been assigned yet at this time, >> and >> accessing it will trigger a null-pointer-dereference issue. Fix it by put >> gd directly. > Function 'put_disk()' checks disk whether is NULL, so I think it's a > 'memleak' problem, not a null-ptr-deref problem. >> Damn, I overlooked it here. Thanks for your review, I will fix the log in v2. >> Signed-off-by: Li Nan <linan122@huawei.com> >> --- >> drivers/mtd/ubi/block.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c >> index 309a42aeaa4c..654bd7372cd8 100644 >> --- a/drivers/mtd/ubi/block.c >> +++ b/drivers/mtd/ubi/block.c >> @@ -434,7 +434,7 @@ int ubiblock_create(struct ubi_volume_info *vi) >> list_del(&dev->list); >> idr_remove(&ubiblock_minor_idr, gd->first_minor); >> out_cleanup_disk: >> - put_disk(dev->gd); >> + put_disk(gd); > > For memleak solution: > > Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com> > >> out_free_tags: >> blk_mq_free_tag_set(&dev->tag_set); >> out_free_dev: > > > .
diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c index 309a42aeaa4c..654bd7372cd8 100644 --- a/drivers/mtd/ubi/block.c +++ b/drivers/mtd/ubi/block.c @@ -434,7 +434,7 @@ int ubiblock_create(struct ubi_volume_info *vi) list_del(&dev->list); idr_remove(&ubiblock_minor_idr, gd->first_minor); out_cleanup_disk: - put_disk(dev->gd); + put_disk(gd); out_free_tags: blk_mq_free_tag_set(&dev->tag_set); out_free_dev: