diff options
author | Josef Bacik <josef@redhat.com> | 2012-06-04 14:03:51 -0400 |
---|---|---|
committer | Chris Mason <chris.mason@oracle.com> | 2012-06-14 21:29:16 -0400 |
commit | 606686eeac4550d2212bf3d621a810407ef5e9bf (patch) | |
tree | 50adade3a750137b68304dc280d7a75436417b12 /fs/btrfs/volumes.h | |
parent | 17ca04aff7e6171df684b7b65804df8830eb8c15 (diff) |
Btrfs: use rcu to protect device->name
Al pointed out that we can just toss out the old name on a device and add a
new one arbitrarily, so anybody who uses device->name in printk could
possibly use free'd memory. Instead of adding locking around all of this he
suggested doing it with RCU, so I've introduced a struct rcu_string that
does just that and have gone through and protected all accesses to
device->name that aren't under the uuid_mutex with rcu_read_lock(). This
protects us and I will use it for dealing with removing the device that we
used to mount the file system in a later patch. Thanks,
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Diffstat (limited to 'fs/btrfs/volumes.h')
-rw-r--r-- | fs/btrfs/volumes.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 3406a88ca83e..74366f27a76b 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h | |||
@@ -58,7 +58,7 @@ struct btrfs_device { | |||
58 | /* the mode sent to blkdev_get */ | 58 | /* the mode sent to blkdev_get */ |
59 | fmode_t mode; | 59 | fmode_t mode; |
60 | 60 | ||
61 | char *name; | 61 | struct rcu_string *name; |
62 | 62 | ||
63 | /* the internal btrfs device id */ | 63 | /* the internal btrfs device id */ |
64 | u64 devid; | 64 | u64 devid; |