linux/fs
Tejun Heo 412a19b64a v9fs: fix error handling in v9fs_session_init()
On failure, v9fs_session_init() returns with the v9fs_session_info
struct partially initialized and expects the caller to invoke
v9fs_session_close() to clean it up; however, it doesn't track whether
the bdi is initialized or not and curiously invokes bdi_destroy() in
both vfs_session_init() failure path too.

A. If v9fs_session_init() fails before the bdi is initialized, the
   follow-up v9fs_session_close() will invoke bdi_destroy() on an
   uninitialized bdi.

B. If v9fs_session_init() fails after the bdi is initialized,
   bdi_destroy() will be called twice on the same bdi - once in the
   failure path of v9fs_session_init() and then by
   v9fs_session_close().

A is broken no matter what.  B used to be okay because bdi_destroy()
allowed being invoked multiple times on the same bdi, which BTW was
broken in its own way - if bdi_destroy() was invoked on an initialiezd
but !registered bdi, it'd fail to free percpu counters.  Since
f0054bb1e1 ("writeback: move backing_dev_info->wb_lock and
->worklist into bdi_writeback"), this no longer work - bdi_destroy()
on an initialized but not registered bdi works correctly but multiple
invocations of bdi_destroy() is no longer allowed.

The obvious culprit here is v9fs_session_init()'s odd and broken error
behavior.  It should simply clean up after itself on failures.  This
patch makes the following updates to v9fs_session_init().

* @rc -> @retval error return propagation removed.  It didn't serve
  any purpose.  Just use @rc.

* Move addition to v9fs_sessionlist to the end of the function so that
  incomplete sessions are not put on the list or iterated and error
  path doesn't have to worry about it.

* Update error handling so that it cleans up after itself.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-08 09:05:06 -06:00
..
9p v9fs: fix error handling in v9fs_session_init() 2015-06-08 09:05:06 -06:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
afs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
autofs4 VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
bfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
btrfs block: remove management of bi_remaining when restoring original bi_end_io 2015-05-22 08:58:55 -06:00
cachefiles VFS: fs/cachefiles: d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
cifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
coda VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
configfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
cramfs
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
devpts VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
dlm netlink: make nlmsg_end() and genlmsg_end() void 2015-01-18 01:03:45 -05:00
ecryptfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
efivarfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
efs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
exofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
exportfs VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry) 2015-02-22 11:38:41 -05:00
ext2 ext2: enable cgroup writeback support 2015-06-02 08:38:04 -06:00
ext3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ext4 writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
f2fs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
fat writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
freevxfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
fscache
fuse writeback: move backing_dev_info->bdi_stat[] into bdi_writeback 2015-06-02 08:33:34 -06:00
gfs2 writeback: move bandwidth related fields from backing_dev_info into bdi_writeback 2015-06-02 08:33:34 -06:00
hfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
hfsplus writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
hostfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
hpfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
hppfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
hugetlbfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
isofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
jbd
jbd2 jbd2: complain about descriptor block checksum errors 2015-01-19 15:59:58 -05:00
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
kernfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
lockd nfsd: eliminate NFSD_DEBUG 2015-04-21 16:16:02 -04:00
logfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
minix VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
ncpfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
nfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
nfs_common
nfsd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
nilfs2 block: remove BIO_EOPNOTSUPP 2015-05-19 09:17:03 -06:00
nls
notify fanotify: fix event filtering with FAN_ONDIR set 2015-03-12 18:46:08 -07:00
ntfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
ocfs2 writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
omfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
openpromfs
overlayfs ovl: upper fs should not be R/O 2015-03-18 10:29:48 +01:00
proc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
pstore Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
qnx4
qnx6 VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
quota Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ramfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
reiserfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
romfs make new_sync_{read,write}() static 2015-04-11 22:29:40 -04:00
squashfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
sysfs sysfs: Only accept read/write permissions for file attributes 2015-03-25 13:27:57 +01:00
sysv VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
tracefs tracing: Have mkdir and rmdir be part of tracefs 2015-02-03 12:48:43 -05:00
ubifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
udf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ufs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
xfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
aio.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-16 23:27:56 -04:00
anon_inodes.c
attr.c
bad_inode.c don't bother with most of the bad_file_ops methods 2015-02-20 04:03:58 -05:00
binfmt_aout.c
binfmt_elf_fdpic.c
binfmt_elf.c mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE 2015-04-14 16:49:05 -07:00
binfmt_em86.c syscalls: implement execveat() system call 2014-12-13 12:42:51 -08:00
binfmt_flat.c
binfmt_misc.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
binfmt_script.c syscalls: implement execveat() system call 2014-12-13 12:42:51 -08:00
block_dev.c bdi: make inode_to_bdi() inline 2015-06-02 08:33:34 -06:00
buffer.c buffer: remove unusued 'ret' variable 2015-06-02 09:22:34 -06:00
char_dev.c fs: introduce f_op->mmap_capabilities for nommu mmap support 2015-01-20 14:02:58 -07:00
compat_binfmt_elf.c
compat_ioctl.c Bluetooth: bnep: Add support for get bnep features via ioctl 2015-04-03 23:21:34 +02:00
compat.c
coredump.c coredump: accept any write method 2015-04-11 22:29:39 -04:00
dax.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
dcache.c VFS: Impose ordering on accesses of d_inode and d_flags 2015-04-15 15:05:28 -04:00
dcookies.c
direct-io.c direct-io: only inc/dec inode->i_dio_count for file systems 2015-04-24 15:45:28 -04:00
drop_caches.c vmscan: per memory cgroup slab shrinkers 2015-02-12 18:54:09 -08:00
eventfd.c eventfd: don't take the spinlock in eventfd_poll 2015-02-17 14:34:52 -08:00
eventpoll.c epoll: optimize setting task running after blocking 2015-02-13 21:21:40 -08:00
exec.c fs: take i_mutex during prepare_binprm for set[ug]id executables 2015-04-19 13:46:21 -07:00
fcntl.c vfs: renumber FMODE_NONOTIFY and add to uniqueness check 2015-01-08 15:10:52 -08:00
fhandle.c
file_table.c ->aio_read and ->aio_write removed 2015-04-11 22:29:43 -04:00
file.c mm: rcu-protected get_mm_exe_file() 2015-04-17 09:04:07 -04:00
filesystems.c
fs_pin.c fs_pin: Allow for the possibility that m_list or s_list go unused. 2015-04-09 11:39:55 -05:00
fs_struct.c
fs-writeback.c writeback: disassociate inodes from dying bdi_writebacks 2015-06-02 08:40:20 -06:00
inode.c writeback: make backing_dev_info host cgroup-specific bdi_writebacks 2015-06-02 08:33:35 -06:00
internal.h trylock_super(): replacement for grab_super_passive() 2015-02-22 11:38:42 -05:00
ioctl.c fsioctl.c: make generic_block_fiemap() signal-tolerant 2015-02-10 14:30:30 -08:00
Kconfig f2fs: relocate Kconfig from misc filesystems 2015-04-10 15:08:35 -07:00
Kconfig.binfmt mm: split ET_DYN ASLR from mmap ASLR 2015-04-14 16:49:05 -07:00
libfs.c VFS: fs library helpers: d_inode() annotations 2015-04-15 15:06:58 -04:00
locks.c proc: show locks in /proc/pid/fdinfo/X 2015-04-17 09:04:12 -04:00
Makefile This adds the new tracefs file system. This has been in linux-next for 2015-04-14 10:22:29 -07:00
mbcache.c
mount.h switch the IO-triggering parts of umount to fs_pin 2015-01-25 23:17:29 -05:00
mpage.c writeback: implement foreign cgroup inode detection 2015-06-02 08:40:20 -06:00
namei.c RCU pathwalk breakage when running into a symlink overmounting something 2015-04-24 15:52:14 -04:00
namespace.c mnt: Update detach_mounts to leave mounts connected 2015-04-09 11:39:57 -05:00
no-block.c
nsfs.c VFS: assorted weird filesystems: d_inode() annotations 2015-04-15 15:06:58 -04:00
open.c xfs: update for 4.1-rc1 2015-04-24 07:08:41 -07:00
pipe.c VFS: assorted weird filesystems: d_inode() annotations 2015-04-15 15:06:58 -04:00
pnode.c mnt: Don't propagate unmounts to locked mounts 2015-04-02 20:34:20 -05:00
pnode.h mnt: Honor MNT_LOCKED when detaching mounts 2015-04-09 11:39:55 -05:00
posix_acl.c VFS: assorted d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
proc_namespace.c vfs: add support for a lazytime mount option 2015-02-05 02:45:00 -05:00
read_write.c new_sync_write(): discard ->ki_pos unless the return value is positive 2015-04-11 22:29:46 -04:00
readdir.c
select.c all arches, signal: move restart_block to struct task_struct 2015-02-12 18:54:12 -08:00
seq_file.c bitmap, cpumask, nodemask: remove dedicated formatting functions 2015-02-13 21:21:39 -08:00
signalfd.c
splice.c dax: unify ext2/4_{dax,}_file_operations 2015-04-15 16:35:20 -07:00
stack.c
stat.c VFS: assorted d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
statfs.c
super.c cleancache: remove limit on the number of cleancache enabled filesystems 2015-04-14 16:49:03 -07:00
sync.c vfs: add support for a lazytime mount option 2015-02-05 02:45:00 -05:00
timerfd.c
utimes.c
xattr.c