linux/fs
Jouni Roivas c3187cf322 hfsplus: prevent corruption in shrinking truncate
I believe there are some issues introduced by commit 31651c6071
("hfsplus: avoid deadlock on file truncation")

HFS+ has extent records which always contains 8 extents.  In case the
first extent record in catalog file gets full, new ones are allocated from
extents overflow file.

In case shrinking truncate happens to middle of an extent record which
locates in extents overflow file, the logic in hfsplus_file_truncate() was
changed so that call to hfs_brec_remove() is not guarded any more.

Right action would be just freeing the extents that exceed the new size
inside extent record by calling hfsplus_free_extents(), and then check if
the whole extent record should be removed.  However since the guard
(blk_cnt > start) is now after the call to hfs_brec_remove(), this has
unfortunate effect that the last matching extent record is removed
unconditionally.

To reproduce this issue, create a file which has at least 10 extents, and
then perform shrinking truncate into middle of the last extent record, so
that the number of remaining extents is not under or divisible by 8.  This
causes the last extent record (8 extents) to be removed totally instead of
truncating into middle of it.  Thus this causes corruption, and lost data.

Fix for this is simply checking if the new truncated end is below the
start of this extent record, making it safe to remove the full extent
record.  However call to hfs_brec_remove() can't be moved to it's previous
place since we're dropping ->tree_lock and it can cause a race condition
and the cached info being invalidated possibly corrupting the node data.

Another issue is related to this one.  When entering into the block
(blk_cnt > start) we are not holding the ->tree_lock.  We break out from
the loop not holding the lock, but hfs_find_exit() does unlock it.  Not
sure if it's possible for someone else to take the lock under our feet,
but it can cause hard to debug errors and premature unlocking.  Even if
there's no real risk of it, the locking should still always be kept in
balance.  Thus taking the lock now just before the check.

Link: https://lkml.kernel.org/r/20210429165139.3082828-1-jouni.roivas@tuxera.com
Fixes: 31651c6071 ("hfsplus: avoid deadlock on file truncation")
Signed-off-by: Jouni Roivas <jouni.roivas@tuxera.com>
Reviewed-by: Anton Altaparmakov <anton@tuxera.com>
Cc: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Cc: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-14 19:41:32 -07:00
..
9p 9p for 5.13-rc1 2021-05-07 11:18:52 -07:00
adfs fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
affs idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
afs afs: Fix speculative status fetches 2021-05-01 11:55:36 -07:00
autofs autofs: should_expire() argument is guaranteed to be positive 2021-03-24 14:14:27 -04:00
befs fs/befs: Delete obsolete TODO file 2021-03-30 16:54:49 -07:00
bfs fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
btrfs for-5.13-rc1-part2-tag 2021-05-11 09:43:16 -07:00
cachefiles fscache, cachefiles: Add alternate API to use kiocb for read/write to cache 2021-04-23 10:14:32 +01:00
ceph Notable items here are a series to take advantage of David Howells' 2021-05-06 10:27:02 -07:00
cifs smb3: if max_channels set to more than one channel request multichannel 2021-05-08 10:51:06 -05:00
coda coda: fix reference counting in coda_file_mmap error path 2021-04-23 14:42:39 -07:00
configfs treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
cramfs cramfs: use %pD instead of messing with file_dentry()->d_name 2021-01-05 23:02:47 -05:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-04-26 08:51:23 -07:00
debugfs Scheduler updates for this cycle are: 2021-04-28 13:33:57 -07:00
devpts
dlm fs: dlm: fix missing unlock on error in accept_from_sock() 2021-03-29 13:28:18 -05:00
ecryptfs Code cleanups and a bug fix 2021-05-06 10:06:39 -07:00
efivarfs efivars: convert to fileattr 2021-04-12 15:04:29 +02:00
efs
erofs erofs: enable big pcluster feature 2021-04-10 03:20:19 +08:00
exfat exfat: speed up iterate/lookup by fixing start point of traversing cluster chain 2021-04-27 20:45:07 +09:00
exportfs exportfs: Add a function to return the raw output from fh_to_dentry() 2020-12-09 09:39:38 -05:00
ext2 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-02 09:14:01 -07:00
ext4 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-02 09:14:01 -07:00
f2fs f2fs: return EINVAL for hole cases in swap file 2021-05-12 07:38:00 -07:00
fat fs: fat: fix spelling typo of values 2021-05-07 00:26:34 -07:00
freevxfs
fscache fscache, cachefiles: Add alternate API to use kiocb for read/write to cache 2021-04-23 10:14:32 +01:00
fuse Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-02 09:14:01 -07:00
gfs2 mm: introduce and use mapping_empty() 2021-05-05 11:27:19 -07:00
hfs fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
hfsplus hfsplus: prevent corruption in shrinking truncate 2021-05-14 19:41:32 -07:00
hostfs Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-02 09:14:01 -07:00
hpfs hpfs: replace one-element array with flexible-array member 2021-05-06 19:24:13 -07:00
hugetlbfs mm/hugetlb: fix F_SEAL_FUTURE_WRITE 2021-05-14 19:41:32 -07:00
iomap mm/filemap: fix readahead return types 2021-05-14 19:41:32 -07:00
isofs isofs: fix fall-through warnings for Clang 2021-05-06 19:24:13 -07:00
jbd2 ext4: fix debug format string warning 2021-04-09 23:32:16 -04:00
jffs2 This pull request contains changes for JFFS2, UBI and UBIFS 2021-05-04 18:08:40 -07:00
jfs jfs: convert to fileattr 2021-04-12 15:04:29 +02:00
kernfs idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
lockd SUNRPC: Make trace_svc_process() display the RPC procedure symbolically 2021-01-25 09:36:23 -05:00
minix fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
netfs netfs: Miscellaneous fixes 2021-04-26 23:23:41 +01:00
nfs NFS client updates for Linux 5.13 2021-05-07 11:23:41 -07:00
nfs_common NFSD: Add an xdr_stream-based encoder for NFSv2/3 ACLs 2021-03-22 10:19:00 -04:00
nfsd NFS client updates for Linux 5.13 2021-05-07 11:23:41 -07:00
nilfs2 Merge branch 'akpm' (patches from Andrew) 2021-05-07 00:34:51 -07:00
nls
notify fanotify_user: use upper_32_bits() to verify mask 2021-03-25 15:33:45 +01:00
ntfs ntfs: check for valid standard information attribute 2021-02-24 13:38:26 -08:00
ocfs2 treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
omfs fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
openpromfs openpromfs: don't do unlock_new_inode() until the new inode is set up 2021-03-12 22:15:22 -05:00
orangefs orangefs: leave files in the page cache for a few micro seconds at least 2021-04-29 08:06:05 -04:00
overlayfs overlayfs update for 5.13 2021-04-30 15:17:08 -07:00
proc proc/sysctl: fix function name error in comments 2021-05-06 19:24:11 -07:00
pstore printk changes for 5.13 2021-04-27 18:09:44 -07:00
qnx4
qnx6
quota quota: report warning limits for realtime space quotas 2021-03-18 17:03:54 +01:00
ramfs ramfs: support O_TMPFILE 2021-02-24 13:38:26 -08:00
reiserfs treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
romfs Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-24 12:26:05 -07:00
squashfs squashfs: fix divide error in calculate_skip() 2021-05-14 19:41:32 -07:00
sysfs sysfs: Support zapping of binary attr mmaps 2021-01-12 14:26:31 +01:00
sysv fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
tracefs tracing: Fix various typos in comments 2021-03-23 14:08:18 -04:00
ubifs This pull request contains changes for JFFS2, UBI and UBIFS 2021-05-04 18:08:40 -07:00
udf useful constants: struct qstr for ".." 2021-04-15 22:36:45 -04:00
ufs useful constants: struct qstr for ".." 2021-04-15 22:36:45 -04:00
unicode .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
vboxsf vboxsf: don't allow to change the inode type 2021-03-12 22:15:00 -05:00
verity fsverity: relax build time dependency on CRYPTO_SHA256 2021-04-22 17:31:32 +10:00
xfs More new code for 5.13-rc1: 2021-05-06 23:54:12 -07:00
zonefs \n 2021-04-29 11:06:13 -07:00
aio.c Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio" 2021-04-30 11:20:39 -07:00
anon_inodes.c fs: anon_inodes: rephrase to appropriate kernel-doc 2021-01-15 12:17:25 -05:00
attr.c ima: handle idmapped mounts 2021-01-24 14:27:20 +01:00
bad_inode.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
binfmt_aout.c
binfmt_elf_fdpic.c coredump: don't bother with do_truncate() 2021-03-08 10:21:11 -05:00
binfmt_elf.c coredump: don't bother with do_truncate() 2021-03-08 10:21:11 -05:00
binfmt_em86.c
binfmt_flat.c binfmt_flat: allow not offsetting data start 2021-04-19 09:56:37 +10:00
binfmt_misc.c binfmt_misc: fix possible deadlock in bm_register_write 2021-03-13 11:27:30 -08:00
binfmt_script.c
block_dev.c block-5.13-2021-05-07 2021-05-07 11:35:12 -07:00
buffer.c Merge branch 'akpm' (patches from Andrew) 2021-05-05 13:50:15 -07:00
char_dev.c
compat_binfmt_elf.c get rid of COMPAT_ELF_EXEC_PAGESIZE 2021-01-06 08:42:51 -05:00
coredump.c coredump: don't bother with do_truncate() 2021-03-08 10:21:11 -05:00
d_path.c constify dentry argument of dentry_path()/dentry_path_raw() 2021-03-21 11:43:58 -04:00
dax.c dax: account DAX entries as nrpages 2021-05-05 11:27:19 -07:00
dcache.c useful constants: struct qstr for ".." 2021-04-15 22:36:45 -04:00
direct-io.c fs: direct-io: fix missing sdio->boundary 2021-04-09 14:54:23 -07:00
drop_caches.c
eventfd.c eventfd: Export eventfd_ctx_do_read() 2020-11-15 09:49:10 -05:00
eventpoll.c fs/epoll: restore waking from ep_done_scan() 2021-05-06 19:24:13 -07:00
exec.c fs: delete repeated words in comments 2021-02-24 13:38:26 -08:00
fcntl.c idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
fhandle.c fs: delete repeated words in comments 2021-02-24 13:38:26 -08:00
file_table.c epoll: take epitem list out of struct file 2020-10-25 20:02:08 -04:00
file.c Merge branch 'work.file' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-03 11:05:28 -07:00
filesystems.c
fs_context.c
fs_parser.c vfs: fs_parser: clean up kernel-doc warnings 2021-04-30 11:20:35 -07:00
fs_pin.c
fs_struct.c
fs_types.c
fs-writeback.c fs: improve comments for writeback_single_inode() 2021-01-13 17:26:50 +01:00
fsopen.c
init.c init: handle idmapped mounts 2021-01-24 14:27:19 +01:00
inode.c mm: remove nrexceptional from inode: remove BUG_ON 2021-05-05 11:27:20 -07:00
internal.h idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
io_uring.c io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers 2021-05-05 15:17:35 -06:00
io-wq.c io-wq: remove unused io_wqe_need_worker() function 2021-04-20 11:24:22 -06:00
io-wq.h io-wq: eliminate the need for a manager thread 2021-04-11 17:42:00 -06:00
ioctl.c vfs: add fileattr ops 2021-04-12 15:04:23 +02:00
Kconfig NFS client updates for Linux 5.13 2021-05-07 11:23:41 -07:00
Kconfig.binfmt binfmt_flat: allow not offsetting data start 2021-04-19 09:56:37 +10:00
kernel_read_file.c fs/kernel_file_read: Add "offset" arg for partial reads 2020-10-05 13:37:04 +02:00
libfs.c libfs: fix kernel-doc for mnt_userns 2021-03-23 11:20:25 +01:00
locks.c Additional fixes and clean-ups for NFSD since tags/nfsd-5.13, 2021-05-05 13:44:19 -07:00
Makefile netfs: Provide readahead and readpage netfs helpers 2021-04-23 10:14:32 +01:00
mbcache.c
mount.h mount: make {lock,unlock}_mount_hash() static 2021-01-24 14:29:34 +01:00
mpage.c block: rename BIO_MAX_PAGES to BIO_MAX_VECS 2021-03-11 07:47:48 -07:00
namei.c fs.idmapped.helpers.v5.13 2021-04-27 12:49:42 -07:00
namespace.c fs/namespace: correct/improve kernel-doc notation 2021-03-31 14:22:55 -06:00
no-block.c
nsfs.c
open.c idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
pipe.c fs: delete repeated words in comments 2021-02-24 13:38:26 -08:00
pnode.c
pnode.h mount: fix mounting of detached mounts onto targets that reside on shared mounts 2021-03-08 15:18:43 +01:00
posix_acl.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
proc_namespace.c fs: introduce MOUNT_ATTR_IDMAP 2021-01-24 14:43:45 +01:00
read_write.c teach sendfile(2) to handle send-to-pipe directly 2021-01-25 23:29:36 -05:00
readdir.c readdir: make sure to verify directory entry for legacy interfaces too 2021-04-17 11:39:49 -07:00
remap_range.c ioctl: handle idmapped mounts 2021-01-24 14:27:19 +01:00
select.c kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data() 2021-03-16 22:13:10 +01:00
seq_file.c seq_file: Add a seq_bprintf function 2021-04-27 15:50:15 -07:00
signalfd.c signal: Introduce TRAP_PERF si_code and si_perf to siginfo 2021-04-16 16:32:41 +02:00
splice.c for-5.12/block-2021-02-17 2021-02-21 11:02:48 -08:00
stack.c
stat.c fs: fix reporting supported extra file attributes for statx() 2021-04-17 23:03:50 -04:00
statfs.c s390,alpha: switch to 64-bit ino_t 2021-02-13 17:17:53 +01:00
super.c fs,security: Add sb_delete hook 2021-04-22 12:22:11 -07:00
sync.c
timerfd.c
userfaultfd.c userfaultfd: add UFFDIO_CONTINUE ioctl 2021-05-05 11:27:22 -07:00
utimes.c utimes: handle idmapped mounts 2021-01-24 14:27:18 +01:00
xattr.c xattr: fix kernel-doc for mnt_userns and vfs xattr helpers 2021-03-23 11:20:26 +01:00