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| author | Ming Lei <ming.lei@canonical.com> | 2016-03-30 03:46:31 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-05-05 00:48:39 +0300 |
| commit | 5b616a05de88d4be0136156a26fae9da855939f6 (patch) | |
| tree | b492763830b8b85c49bb7a50534f4a1d5a9447c3 /block/partition-generic.c | |
| parent | 8c9aef03d3b540b6885e7534a885ea25f62dd9ed (diff) | |
| download | linux-5b616a05de88d4be0136156a26fae9da855939f6.tar.xz | |
block: partition: initialize percpuref before sending out KOBJ_ADD
commit b30a337ca27c4f40439e4bfb290cba5f88d73bb7 upstream.
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)
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'block/partition-generic.c')
| -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 746935a5973c..a241e3900bc9 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -349,15 +349,20 @@ 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); @@ -366,6 +371,8 @@ 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); |