linux/block
Li Zefan 65dff759d2 cgroup: fix cgroup_path() vs rename() race
rename() will change dentry->d_name. The result of this race can
be worse than seeing partially rewritten name, but we might access
a stale pointer because rename() will re-allocate memory to hold
a longer name.

As accessing dentry->name must be protected by dentry->d_lock or
parent inode's i_mutex, while on the other hand cgroup-path() can
be called with some irq-safe spinlocks held, we can't generate
cgroup path using dentry->d_name.

Alternatively we make a copy of dentry->d_name and save it in
cgrp->name when a cgroup is created, and update cgrp->name at
rename().

v5: use flexible array instead of zero-size array.
v4: - allocate root_cgroup_name and all root_cgroup->name points to it.
    - add cgroup_name() wrapper.
v3: use kfree_rcu() instead of synchronize_rcu() in user-visible path.
v2: make cgrp->name RCU safe.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-03-04 09:50:08 -08:00
..
partitions block/partitions: optimize memory allocation in check_partition() 2013-02-27 19:10:21 -08:00
blk-cgroup.c Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block 2013-02-28 12:52:24 -08:00
blk-cgroup.h cgroup: fix cgroup_path() vs rename() race 2013-03-04 09:50:08 -08:00
blk-core.c Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block 2013-02-28 12:52:24 -08:00
blk-exec.c Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block 2013-02-28 12:52:24 -08:00
blk-flush.c block: account iowait time when waiting for completion of IO request 2013-02-15 16:45:07 +01:00
blk-integrity.c bdi: allow block devices to say that they require stable page writes 2013-02-21 17:22:19 -08:00
blk-ioc.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
blk-iopoll.c tree-wide: fix assorted typos all over the place 2009-12-04 15:39:55 +01:00
blk-lib.c block: account iowait time when waiting for completion of IO request 2013-02-15 16:45:07 +01:00
blk-map.c block: re-use existing 'reading' variable instead of checking direction again 2011-12-21 15:27:24 +01:00
blk-merge.c block: Implement support for WRITE SAME 2012-09-20 14:31:45 +02:00
blk-settings.c block: discard granularity might not be power of 2 2012-12-14 20:46:04 +01:00
blk-softirq.c sched, block: Unify cache detection 2012-01-27 13:28:48 +01:00
blk-sysfs.c block: RCU free request_queue 2013-01-09 08:05:13 -08:00
blk-tag.c block/blk-tag.c: Remove useless kfree 2012-09-12 22:25:12 +02:00
blk-throttle.c block: Rename queue dead flag 2012-12-06 14:30:58 +01:00
blk-timeout.c block: Drop dead function blk_abort_queue() 2012-06-15 08:46:23 +02:00
blk.h block,elevator: use new hashtable implementation 2013-01-11 14:43:13 +01:00
bsg-lib.c bsg: Remove unused function bsg_goose_queue() 2012-12-06 14:33:02 +01:00
bsg.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
cfq-iosched.c Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block 2013-02-28 12:52:24 -08:00
compat_ioctl.c block: Add BLKROTATIONAL ioctl 2012-01-11 16:29:31 +01:00
deadline-iosched.c deadline: Allow 0ms deadline latency, increase the read speed 2012-12-09 19:19:23 +01:00
elevator.c Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block 2013-02-28 12:52:24 -08:00
genhd.c block: convert to idr_alloc() 2013-02-27 19:10:15 -08:00
ioctl.c Merge branch 'for-3.7/core' of git://git.kernel.dk/linux-block 2012-10-11 09:04:23 +09:00
Kconfig block: don't select PERCPU_RWSEM 2013-02-22 10:42:45 +01:00
Kconfig.iosched blkcg: make CONFIG_BLK_CGROUP bool 2012-03-06 21:27:21 +01:00
Makefile separate partition format handling from generic code 2012-01-03 22:54:06 -05:00
noop-iosched.c elevator: make elevator_init_fn() return 0/-errno 2012-03-06 21:27:21 +01:00
partition-generic.c block/partitions: optimize memory allocation in check_partition() 2013-02-27 19:10:21 -08:00
scsi_ioctl.c scsi: Silence unnecessary warnings about ioctl to partition 2012-06-15 12:52:46 +02:00