diff options
| author | Ming Lei <ming.lei@canonical.com> | 2016-03-30 08:46:31 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2016-03-29 19:18:14 -0600 |
| commit | b30a337ca27c4f40439e4bfb290cba5f88d73bb7 (patch) | |
| tree | 07da263067ec36686177990a48000beb0ceb2eae /block | |
| parent | 1993b176a8224e371e0732ffada7ab9eb3b0912b (diff) | |
| download | linux-b30a337ca27c4f40439e4bfb290cba5f88d73bb7.tar.gz | |
block: partition: initialize percpuref before sending out KOBJ_ADD
The initialization of partition's percpu_ref should have been done before sending out KOBJ_ADD uevent, which may cause userspace to read partition table. So the uninitialized percpu_ref may be accessed in data path. This patch fixes this issue reported by Naveen. Reported-by: Naveen Kaje <nkaje@codeaurora.org> Tested-by: Naveen Kaje <nkaje@codeaurora.org> Fixes: 6c71013ecb7e2(block: partition: convert percpu ref) Cc: <stable@vger.kernel.org> # v4.3+ Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/partition-generic.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/block/partition-generic.c b/block/partition-generic.c index 5d8701941054..84c53f04777a 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -361,15 +361,20 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno, goto out_del; } + err = hd_ref_init(p); + if (err) { + if (flags & ADDPART_FLAG_WHOLEDISK) + goto out_remove_file; + goto out_del; + } + /* everything is up and running, commence */ rcu_assign_pointer(ptbl->part[partno], p); /* suppress uevent if the disk suppresses it */ if (!dev_get_uevent_suppress(ddev)) kobject_uevent(&pdev->kobj, KOBJ_ADD); - - if (!hd_ref_init(p)) - return p; + return p; out_free_info: free_part_info(p); @@ -378,6 +383,8 @@ out_free_stats: out_free: kfree(p); return ERR_PTR(err); +out_remove_file: + device_remove_file(pdev, &dev_attr_whole_disk); out_del: kobject_put(p->holder_dir); device_del(pdev); |