linux/fs
Steven Rostedt 56a83cc929 debugfs: dont stop on first failed recursive delete
debugfs: dont stop on first failed recursive delete

While running a while loop of removing a module that removes a debugfs
directory with debugfs_remove_recursive, and at the same time doing a
while loop of cat of a file in that directory, I would hit a point where
somehow the cat of the file caused the remove to fail.

The result is that other files did not get removed when the module
was removed. I simple read of one of those file can oops the kernel
because the operations to the file no longer exist (removed by module).

The funny thing is that the file being cat'ed was removed. It was
the siblings that were not. I see in the code to debugfs_remove_recursive
there's a test that checks if the child fails to bail out of the loop
to prevent an infinite loop.

What this patch does is to still try any siblings in that directory.
If all the siblings fail, or there are no more siblings, then we exit
the loop.

This fixes the above symptom, but...

This is no full proof. It makes the debugfs_remove_recursive a bit more
robust, but it does not explain why the one file failed. There may
be some kind of delay deletion that makes the debugfs think it did
not succeed. So this patch is more of a fix for the symptom but not
the disease.

This patch still makes the debugfs_remove_recursive more robust and
until I can find out why the bug exists, this patch will keep
the kernel from oopsing in most cases.  Even after the cause is found
I think this change can stand on its own and should be kept.

[ Impact: prevent kernel oops on module unload and reading debugfs files ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:30:24 -07:00
..
9p Fix a leak in failure exit in 9p ->get_sb() 2009-05-09 10:49:40 -04:00
adfs Fix adfs GET_FRAG_ID() on big-endian 2009-06-11 21:36:14 -04:00
affs affs: add ->sync_fs 2009-06-11 21:36:14 -04:00
afs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
autofs switch follow_down() 2009-06-11 21:36:01 -04:00
autofs4 switch follow_down() 2009-06-11 21:36:01 -04:00
befs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
bfs bfs: add ->sync_fs 2009-06-11 21:36:14 -04:00
btrfs enforce ->sync_fs is only called for rw superblock 2009-06-11 21:36:06 -04:00
cachefiles enforce ->sync_fs is only called for rw superblock 2009-06-11 21:36:06 -04:00
cifs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
coda splice: implement default splice_read method 2009-05-11 14:13:10 +02:00
configfs configfs: Rework configfs_depend_item() locking and make lockdep happy 2009-04-30 10:48:26 -07:00
cramfs fs/cramfs: return f_fsid for statfs(2) 2009-04-02 19:05:08 -07:00
debugfs debugfs: dont stop on first failed recursive delete 2009-06-15 21:30:24 -07:00
devpts devpts: unregister the file system on error 2009-06-11 08:51:06 -07:00
dlm dlm: use more NOFS allocation 2009-05-15 11:24:59 -05:00
ecryptfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
efs fs/efs: return f_fsid for statfs(2) 2009-04-02 19:05:09 -07:00
exofs [SCSI] Merge branch 'linus' 2009-06-12 10:02:03 -05:00
exportfs
ext2 trivial: ext2: fix a typo in comment in ext2.h 2009-06-12 18:01:44 +02:00
ext3 Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
ext4 Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
fat fat: add ->sync_fs 2009-06-11 21:36:15 -04:00
freevxfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
fscache FS-Cache: Fixup renamed filenames in comments in internal.h 2009-05-27 10:20:13 -07:00
fuse Merge branch 'cuse' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse 2009-06-12 09:31:20 -07:00
gfs2 GFS2: Remove lock_kernel from gfs2_put_super() 2009-06-12 13:40:47 +01:00
hfs hfs: add ->sync_fs 2009-06-11 21:36:15 -04:00
hfsplus hfsplus: add ->sync_fs 2009-06-11 21:36:16 -04:00
hostfs constify dentry_operations: misc filesystems 2009-03-27 14:44:00 -04:00
hpfs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
hppfs hppfs: hppfs_read_file() may return -ERROR 2009-04-02 19:04:53 -07:00
hugetlbfs Merge branch 'master' into next 2009-05-22 18:40:59 +10:00
isofs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
jbd jbd: fix race in buffer processing in commit code 2009-06-09 16:59:03 -07:00
jbd2 jbd2: Fix minor typos in comments in fs/jbd2/journal.c 2009-06-09 00:06:20 -04:00
jffs2 jffs2: call jffs2_write_super from jffs2_sync_fs 2009-06-11 21:36:16 -04:00
jfs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
lockd lockd: fix list corruption on lockd restart 2009-05-06 17:19:36 -04:00
minix switch minix to simple_fsync() 2009-06-11 21:36:12 -04:00
ncpfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
nfs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
nfs_common
nfsd switch follow_down() 2009-06-11 21:36:01 -04:00
nilfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2 2009-06-15 09:13:49 -07:00
nls
notify fsnotify: allow groups to set freeing_mark to null 2009-06-11 14:57:55 -04:00
ntfs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
ocfs2 Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
omfs switch omfs to simple_fsync() 2009-06-11 21:36:13 -04:00
openpromfs
partitions Merge branch 'for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6 2009-06-12 09:29:42 -07:00
proc Move junk from proc_fs.h to fs/proc/internal.h 2009-06-11 21:36:01 -04:00
qnx4 fs/qnx4: sanitize includes 2009-06-11 21:36:12 -04:00
quota quota: cleanup dquota sync functions (version 4) 2009-06-11 21:36:04 -04:00
ramfs ramfs: ignore unknown mount options 2009-06-14 17:58:25 -07:00
reiserfs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
romfs ROMFS: romfs_dev_read() error ignored 2009-05-09 10:49:41 -04:00
smbfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
squashfs push BKL down into ->put_super 2009-06-11 21:36:07 -04:00
sysfs Sysfs: fix possible memleak in sysfs_follow_link 2009-06-15 21:30:23 -07:00
sysv sysv: add ->sync_fs 2009-06-11 21:36:16 -04:00
ubifs Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
udf switch udf to simple_fsync() 2009-06-11 21:36:13 -04:00
ufs ufs: add ->sync_fs 2009-06-11 21:36:16 -04:00
xfs Merge branch 'master' of git://oss.sgi.com/xfs/xfs into for-linus 2009-06-12 21:28:59 -05:00
aio.c aio: lookup_ioctx can return the wrong value when looking up a bogus context 2009-03-19 15:57:18 -07:00
anon_inodes.c constify dentry_operations: rest 2009-03-27 14:44:03 -04:00
attr.c vfs: Use lowercase names of quota functions 2009-03-26 02:18:35 +01:00
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c ptrace: s/parent/real_parent/ in binfmt_elf_fdpic.c 2009-05-02 15:36:10 -07:00
binfmt_elf.c Trim includes in binfmt_elf 2009-03-31 23:00:27 -04:00
binfmt_em86.c
binfmt_flat.c flat: fix data sections alignment 2009-05-29 08:40:02 -07:00
binfmt_misc.c
binfmt_script.c
binfmt_som.c Don't crap into descriptor table in binfmt_som 2009-03-31 23:00:28 -04:00
bio-integrity.c block: add private bio_set for bio integrity allocations 2009-03-24 12:35:17 +01:00
bio.c trivial: fix typo in bio_alloc kernel doc 2009-06-12 18:01:47 +02:00
block_dev.c vfs: Rename fsync_super() to sync_filesystem() (version 4) 2009-06-11 21:36:04 -04:00
buffer.c Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block 2009-06-11 11:10:35 -07:00
char_dev.c fs: Remove i_cindex from struct inode 2009-06-11 21:36:09 -04:00
compat_binfmt_elf.c
compat_ioctl.c trivial: fix typo compatiable/compatiability has extra 'a'. 2009-06-12 18:01:46 +02:00
compat.c trivial: fix comment typo in fs/compat.c 2009-06-12 18:01:44 +02:00
dcache.c dcache: extrace and use d_unlinked() 2009-06-11 21:36:06 -04:00
dcookies.c [CVE-2009-0029] System call wrapper special cases 2009-01-14 14:15:18 +01:00
direct-io.c block: Do away with the notion of hardsect_size 2009-05-22 23:22:54 +02:00
drop_caches.c vfs: skip I_CLEAR state inodes 2009-04-02 19:04:48 -07:00
eventfd.c eventfd: export eventfd_signal and eventfd_fget for lguest 2009-06-12 22:27:09 +09:30
eventpoll.c epoll: fix size check in epoll_create() 2009-05-12 14:11:35 -07:00
exec.c Merge branch 'perfcounters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-06-11 14:01:07 -07:00
fcntl.c dup2: Fix return value with oldfd == newfd and invalid fd 2009-05-11 12:18:06 -07:00
fifo.c
file_table.c fs: move mark_files_ro into file_table.c 2009-06-11 21:36:02 -04:00
file.c
filesystems.c fs: Mark get_filesystem_list() as __init function. 2009-04-20 23:02:52 -04:00
fs_struct.c Get rid of indirect include of fs_struct.h 2009-03-31 23:00:27 -04:00
fs-writeback.c fs: block_dump missing dentry locking 2009-06-11 21:36:10 -04:00
generic_acl.c New helper - current_umask() 2009-03-31 23:00:26 -04:00
inode.c trivial: fs/inode: Fix typo in file_update_time nanodoc 2009-06-12 18:01:45 +02:00
internal.h Trim a bit of crap from fs.h 2009-06-11 21:36:07 -04:00
ioctl.c fiemap: fix problem with setting FIEMAP_EXTENT_LAST 2009-05-06 16:36:09 -07:00
ioprio.c [CVE-2009-0029] System call wrappers part 28 2009-01-14 14:15:30 +01:00
Kconfig CUSE: implement CUSE - Character device in Userspace 2009-06-09 11:24:11 +02:00
Kconfig.binfmt CORE_DUMP_DEFAULT_ELF_HEADERS depends on ELF_CORE 2009-01-09 16:54:41 -08:00
libfs.c New helper - simple_fsync() 2009-06-11 21:36:11 -04:00
locks.c [CVE-2009-0029] System call wrappers part 16 2009-01-14 14:15:25 +01:00
Makefile nilfs2: update makefile and Kconfig 2009-04-07 08:31:16 -07:00
mbcache.c
mpage.c ext4: Properly initialize the buffer_head state 2009-05-13 15:13:42 -04:00
namei.c switch lookup_mnt() 2009-06-11 21:36:01 -04:00
namespace.c Push BKL down into do_remount_sb() 2009-06-11 21:36:08 -04:00
nfsctl.c [CVE-2009-0029] System call wrappers part 27 2009-01-14 14:15:29 +01:00
no-block.c
open.c fs: introduce mnt_clone_write 2009-06-11 21:36:02 -04:00
pipe.c splice: implement default splice_read method 2009-05-11 14:13:10 +02:00
pnode.c
pnode.h
posix_acl.c
read_write.c splice: implement default splice_read method 2009-05-11 14:13:10 +02:00
read_write.h
readdir.c [CVE-2009-0029] System call wrappers part 32 2009-01-14 14:15:31 +01:00
select.c [CVE-2009-0029] System call wrappers part 32 2009-01-14 14:15:31 +01:00
seq_file.c cpumask: fix seq_bitmap_*() functions. 2009-03-30 22:05:11 +10:30
signalfd.c [CVE-2009-0029] System call wrappers part 31 2009-01-14 14:15:31 +01:00
splice.c splice: fix kmaps in default_file_splice_write() 2009-05-19 11:37:46 +02:00
stack.c
stat.c kill vfs_stat_fd / vfs_lstat_fd 2009-04-20 23:02:52 -04:00
super.c Push BKL down into ->remount_fs() 2009-06-11 21:36:11 -04:00
sync.c remove the call to ->write_super in __sync_filesystem 2009-06-11 21:36:17 -04:00
timerfd.c timerfd: add flags check 2009-02-18 15:37:53 -08:00
utimes.c [CVE-2009-0029] System call wrappers part 30 2009-01-14 14:15:30 +01:00
xattr_acl.c
xattr.c fs: introduce mnt_clone_write 2009-06-11 21:36:02 -04:00