Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-03 17:41:22 +00:00
Code Issues Packages Projects Releases Wiki Activity
6623d9a0b0
linux/fs
History
Christian Brauner 6623d9a0b0 btrfs: allow idmapped INO_LOOKUP_USER ioctl 
The INO_LOOKUP_USER is an unprivileged version of the INO_LOOKUP ioctl
and has the following restrictions. The main difference between the two
is that INO_LOOKUP is filesystem wide operation wheres INO_LOOKUP_USER
is scoped beneath the file descriptor passed with the ioctl.
Specifically, INO_LOOKUP_USER must adhere to the following restrictions:

- The caller must be privileged over each inode of each path component
  for the path they are trying to lookup.

- The path for the subvolume the caller is trying to lookup must be reachable
  from the inode associated with the file descriptor passed with the ioctl.

The second condition makes it possible to scope the lookup of the path
to the mount identified by the file descriptor passed with the ioctl.
This allows us to enable this ioctl on idmapped mounts.

Specifically, this is possible because all child subvolumes of a parent
subvolume are reachable when the parent subvolume is mounted. So if the
user had access to open the parent subvolume or has been given the fd
then they can lookup the path if they had access to it provided they
were privileged over each path component.

Note, the INO_LOOKUP_USER ioctl allows a user to learn the path and name
of a subvolume even though they would otherwise be restricted from doing
so via regular VFS-based lookup.

So think about a parent subvolume with multiple child subvolumes.
Someone could mount he parent subvolume and restrict access to the child
subvolumes by overmounting them with empty directories. At this point
the user can't traverse the child subvolumes and they can't open files
in the child subvolumes.  However, they can still learn the path of
child subvolumes as long as they have access to the parent subvolume by
using the INO_LOOKUP_USER ioctl.

The underlying assumption here is that it's ok that the lookup ioctls
can't really take mounts into account other than the original mount the
fd belongs to during lookup. Since this assumption is baked into the
original INO_LOOKUP_USER ioctl we can extend it to idmapped mounts.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:15 +02:00
..
9p 9p: migrate from sync_inode to filemap_fdatawrite_wbc 2021-08-23 13:19:07 +02:00
adfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
affs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
afs afs: Remove redundant assignment to ret 2021-07-21 15:11:22 +01:00
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 mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
btrfs btrfs: allow idmapped INO_LOOKUP_USER ioctl 2021-08-23 13:19:15 +02:00
cachefiles fscache, cachefiles: Add alternate API to use kiocb for read/write to cache 2021-04-23 10:14:32 +01:00
ceph ceph: take snap_empty_lock atomically with snaprealm refcount change 2021-08-04 19:20:29 +02:00
cifs cifs: Call close synchronously during unlink/rename/lease break. 2021-08-12 11:29:58 -05:00
coda coda: fix reference counting in coda_file_mmap error path 2021-04-23 14:42:39 -07:00
configfs configfs: restore the kernel v5.13 text attribute write behavior 2021-08-09 16:56:00 +02:00
cramfs cramfs: use %pD instead of messing with file_dentry()->d_name 2021-01-05 23:02:47 -05:00
crypto fscrypt: fix derivation of SipHash keys on big endian CPUs 2021-06-05 00:52:52 -07:00
debugfs Linux 5.13-rc6 2021-06-14 09:07:45 +02:00
devpts
dlm fs: dlm: invalid buffer access in lookup error 2021-06-11 12:44:47 -05:00
ecryptfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
efivarfs efivars: convert to fileattr 2021-04-12 15:04:29 +02:00
efs
erofs erofs: clean up file headers & footers 2021-06-08 00:41:24 +08:00
exfat Description for this pull request: 2021-07-06 11:06:04 -07:00
exportfs exportfs: Add a function to return the raw output from fh_to_dentry() 2020-12-09 09:39:38 -05:00
ext2 fs/ext2: Avoid page_address on pages returned by ext2_get_page 2021-07-16 12:36:51 +02:00
ext4 ext4: fix potential htree corruption when growing large_dir directories 2021-08-06 13:00:49 -04:00
f2fs f2fs: drop dirty node pages when cp is in error status 2021-07-06 22:05:06 -07:00
fat mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -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 'for-5.14/dax' into libnvdimm-fixes 2021-08-11 12:04:43 -07:00
gfs2 Various minor gfs2 cleanups and fixes 2021-06-29 20:23:08 -07:00
hfs hfs: add lock nesting notation to hfs_find_init 2021-07-15 10:13:49 -07:00
hfsplus hfsplus: report create_date to kstat.btime 2021-07-01 11:06:06 -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 mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
hugetlbfs hugetlbfs: fix mount mode command line processing 2021-07-23 17:43:28 -07:00
iomap iomap: Don't create iomap_page objects in iomap_page_mkwrite_actor 2021-07-15 09:58:06 -07:00
isofs isofs: remove redundant continue statement 2021-06-17 17:11:42 +02:00
jbd2 ext4: inline jbd2_journal_[un]register_shrinker() 2021-07-08 08:37:31 -04:00
jffs2 This pull request contains changes for JFFS2, UBI and UBIFS 2021-05-04 18:08:40 -07:00
jfs JFS fixes for 5.14 2021-07-02 14:25:17 -07:00
kernfs Driver core changes for 5.14-rc1 2021-07-05 13:51:41 -07:00
lockd lockd: Update the NLMv4 SHARE results encoder to use struct xdr_stream 2021-07-06 20:14:44 -04:00
minix mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
netfs netfs: fix test for whether we can skip read when writing beyond EOF 2021-06-21 21:24:07 +01:00
nfs NFS client updates for Linux 5.14 2021-07-09 09:43:57 -07:00
nfs_common nfs_common: fix doc warning 2021-07-06 20:14:41 -04:00
nfsd block-5.14-2021-07-08 2021-07-09 12:05:33 -07:00
nilfs2 Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
nls
notify ucounts: add missing data type changes 2021-08-09 15:45:02 -05:00
ntfs Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:30:04 -07:00
ocfs2 ocfs2: issue zeroout to EOF blocks 2021-07-30 10:14:39 -07:00
omfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
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: fix orangefs df output. 2021-06-28 08:40:08 -04:00
overlayfs ovl: fix uninitialized pointer read in ovl_lookup_real_one() 2021-08-10 10:21:30 +02:00
proc Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
pstore for-5.14/drivers-2021-06-29 2021-06-30 12:21:16 -07:00
qnx4
qnx6
quota quota: remove unnecessary oom message 2021-06-22 10:40:52 +02:00
ramfs fs: move ramfs_aops to libfs 2021-06-29 10:53:48 -07:00
reiserfs reiserfs: check directory items on read from disk 2021-07-16 12:36:51 +02:00
romfs
squashfs squashfs: add option to panic on errors 2021-06-29 10:53:46 -07:00
sysfs sysfs: Support zapping of binary attr mmaps 2021-01-12 14:26:31 +01:00
sysv mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
tracefs tracing: Fix various typos in comments 2021-03-23 14:08:18 -04:00
ubifs ubifs: Set/Clear I_LINKABLE under i_lock for whiteout inode 2021-06-22 09:21:39 +02:00
udf \n 2021-07-01 12:06:39 -07:00
ufs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
unicode .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
vboxsf vboxsf: Add support for the atomic_open directory-inode op 2021-06-23 14:36:52 +02:00
verity fsverity: relax build time dependency on CRYPTO_SHA256 2021-04-22 17:31:32 +10:00
xfs Fixes for 5.14-rc4: 2021-08-01 12:07:23 -07:00
zonefs zonefs: remove redundant null bio check 2021-07-16 13:45:18 +09:00
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: remove in-tree usage of MAP_EXECUTABLE 2021-06-29 10:53:50 -07:00
binfmt_elf_fdpic.c Merge branch 'akpm' (patches from Andrew) 2021-06-29 17:29:11 -07:00
binfmt_elf.c Merge branch 'akpm' (patches from Andrew) 2021-06-29 17:29:11 -07:00
binfmt_flat.c binfmt: remove in-tree usage of MAP_EXECUTABLE 2021-06-29 10:53:50 -07:00
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-5.14-2021-07-30 2021-07-30 11:08:12 -07:00
buffer.c mm/writeback: move __set_page_dirty() to core mm 2021-06-29 10:53:48 -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 Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
d_path.c getcwd(2): clean up error handling 2021-05-18 20:15:58 -04:00
dax.c Merge branch 'for-5.14/dax' into libnvdimm-fixes 2021-08-11 12:04:43 -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
eventpoll.c fs/epoll: restore waking from ep_done_scan() 2021-05-06 19:24:13 -07:00
exec.c Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
fcntl.c fcntl: Fix unreachable code in do_fcntl() 2021-07-12 11:09:13 -05:00
fhandle.c switch file_open_root() to struct path 2021-04-07 13:56:43 -04:00
file_table.c
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: add vfs_parse_fs_param_source() helper 2021-07-14 09:19:06 -07:00
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: kill sync_inode 2021-08-23 13:19:07 +02:00
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 cgroup1: fix leaked context root causing sporadic NULL deref in LTP 2021-07-21 06:39:20 -10:00
io_uring.c io_uring: fix xa_alloc_cycle() error return value check 2021-08-20 14:59:58 -06:00
io-wq.c io-wq: fix IO_WORKER_F_FIXED issue in create_io_worker() 2021-08-09 19:59:06 -06:00
io-wq.h io_uring: move creds from io-wq work to io_kiocb 2021-06-18 09:22:02 -06:00
ioctl.c vfs: add fileattr ops 2021-04-12 15:04:23 +02:00
Kconfig mm: hugetlb: introduce CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON 2021-06-30 20:47:26 -07:00
Kconfig.binfmt binfmt: remove support for em86 (alpha only) 2021-07-25 22:33:03 -07:00
kernel_read_file.c switch file_open_root() to struct path 2021-04-07 13:56:43 -04:00
libfs.c fs: remove noop_set_page_dirty() 2021-06-29 10:53:48 -07:00
locks.c Additional fixes and clean-ups for NFSD since tags/nfsd-5.13, 2021-05-05 13:44:19 -07:00
Makefile binfmt: remove support for em86 (alpha only) 2021-07-25 22:33:03 -07:00
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 namei: add mapping aware lookup helper 2021-08-23 13:19:12 +02:00
namespace.c File locking change for v5.14 2021-08-21 10:50:22 -07:00
no-block.c
nsfs.c
open.c Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
pipe.c pipe: avoid unnecessary EPOLLET wakeups under normal loads 2021-08-18 11:39:46 -07:00
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: disallow extremely large seq buffer allocations 2021-07-19 17:18:48 -07:00
signalfd.c signalfd: Remove SIL_PERF_EVENT fields from signalfd_siginfo 2021-05-18 16:20:54 -05:00
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 block: move bd_mutex to struct gendisk 2021-06-01 07:44:32 -06:00
sync.c
timerfd.c
userfaultfd.c userfaultfd: do not untag user pointers 2021-07-23 17:43:28 -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