Граф коммитов

682 Коммитов

Автор SHA1 Сообщение Дата
Linus Torvalds 682a8e2b41 Code cleanups and a bug fix
- W=1 compiler warning cleanups
 - Mutex initialization simplification
 - Protect against NULL pointer exception during mount
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEKvuQkp28KvPJn/fVfL7QslYSS/0FAmCTTQoRHGNvZGVAdHlo
 aWNrcy5jb20ACgkQfL7QslYSS/3M4RAAlpWKtZlUd83gr2wS7jKX+WR6Bmc9yu2Q
 hH9eJRca1O3LQHzRfsh6Y4PQmQD10kPOZUD4Qfy5FgYebNu/yapjx+2O7VpXeiiu
 b+Ien7l5f2qyBUjjIypW7m0T52YHDV5vc2nWkGoxYl3g6ecla3THdCmzpMD7iAUa
 7tNdDd+zF+I2Lm0nVW2r/wLSUHoWs1d5u5GKOWkWgyEa80A4F6nHR6g+1GuUYhpE
 8jfo5NnGGYjM3M+uH2MUBGan7K99YH+bTTsCSeEOSx7MK1X7zeH9pKaHIpPIYI6n
 m7iymS0qAfkdlK8GEMLVTgjVPY3Jh6f7iLug2+js4y+j2sXsBZvJzQHRS6uKu4YP
 dW/Da/0qntnnIyE0gD/SnwRGjTfv3LBbnw2vJSv2d9z9N50gIHJB43ZFP4XYfK0n
 WWHce7W7O+lo+4ZPTDd4G6Nz96Fi9Bl6bMA71Pw6P/J9KWnl6LOyp95YHifDlZ+f
 asYkxOvHDJagA6mKos0lnc/GT8IPAe65p6Jsq0IE32hplS4Cq9ajrUZ+3+VHsADr
 ZvG84IWe2vK2fWgvcaSpxLx3BhJTh/qkN/ISOykzVMWbet114XeXCC4hOQOVqU/A
 fsJgq6TeMMlpBeUnHobRN0AihGpatgiaMq7GtlZyEmk4Rkotf65vw/gmnR301pDq
 tTVVPw1XTdQ=
 =aHZx
 -----END PGP SIGNATURE-----

Merge tag 'ecryptfs-5.13-rc1-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull ecryptfs updates from Tyler Hicks:
 "Code cleanups and a bug fix

   - W=1 compiler warning cleanups

   - Mutex initialization simplification

   - Protect against NULL pointer exception during mount"

* tag 'ecryptfs-5.13-rc1-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  ecryptfs: fix kernel panic with null dev_name
  ecryptfs: remove unused helpers
  ecryptfs: Fix typo in message
  eCryptfs: Use DEFINE_MUTEX() for mutex lock
  ecryptfs: keystore: Fix some kernel-doc issues and demote non-conformant headers
  ecryptfs: inode: Help out nearly-there header and demote non-conformant ones
  ecryptfs: mmap: Help out one function header and demote other abuses
  ecryptfs: crypto: Supply some missing param descriptions and demote abuses
  ecryptfs: miscdev: File headers are not good kernel-doc candidates
  ecryptfs: main: Demote a bunch of non-conformant kernel-doc headers
  ecryptfs: messaging: Add missing param descriptions and demote abuses
  ecryptfs: super: Fix formatting, naming and kernel-doc abuses
  ecryptfs: file: Demote kernel-doc abuses
  ecryptfs: kthread: Demote file header and provide description for 'cred'
  ecryptfs: dentry: File headers are not good candidates for kernel-doc
  ecryptfs: debug: Demote a couple of kernel-doc abuses
  ecryptfs: read_write: File headers do not make good candidates for kernel-doc
  ecryptfs: use DEFINE_MUTEX() for mutex lock
  eCryptfs: add a semicolon
2021-05-06 10:06:39 -07:00
Linus Torvalds b28866f4bb Merge branch 'work.ecryptfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull exryptfs updates from Al Viro:
 "The interesting part here is (ecryptfs) lock_parent() fixes - its
  treatment of ->d_parent had been very wrong.

  The rest is trivial cleanups"

* 'work.ecryptfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ecryptfs: ecryptfs_dentry_info->crypt_stat is never used
  ecryptfs: get rid of unused accessors
  ecryptfs: saner API for lock_parent()
  ecryptfs: get rid of pointless dget/dput in ->symlink() and ->link()
2021-05-02 09:05:54 -07:00
Jeffrey Mitchell 9046625511 ecryptfs: fix kernel panic with null dev_name
When mounting eCryptfs, a null "dev_name" argument to ecryptfs_mount()
causes a kernel panic if the parsed options are valid. The easiest way to
reproduce this is to call mount() from userspace with an existing
eCryptfs mount's options and a "source" argument of 0.

Error out if "dev_name" is null in ecryptfs_mount()

Fixes: 237fead619 ("[PATCH] ecryptfs: fs/Makefile and fs/Kconfig")
Cc: stable@vger.kernel.org
Signed-off-by: Jeffrey Mitchell <jeffrey.mitchell@starlab.io>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 05:50:32 +00:00
Christian Brauner 7f06ecd3af ecryptfs: remove unused helpers
Remove two helpers that are unused.

Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Tyler Hicks <code@tyhicks.com>
Cc: ecryptfs@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:44:25 +00:00
Sascha Hauer 1abbe1106d ecryptfs: Fix typo in message
ecryptfs_decrypt_page() issues a warning "Error encrypting extent". This
should be "Error decrypting extent" instead.

Fixes: 0216f7f792 ("eCryptfs: replace encrypt, decrypt, and inode size write")
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Ye Bin 724fa86291 eCryptfs: Use DEFINE_MUTEX() for mutex lock
mutex lock can be initialized automatically with DEFINE_MUTEX()
rather than explicitly calling mutex_init().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones ffbed072be ecryptfs: keystore: Fix some kernel-doc issues and demote non-conformant headers
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/keystore.c:25: warning: Incorrect use of kernel-doc format:  * request_key returned an error instead of a valid key address;
 fs/ecryptfs/keystore.c:30: warning: Function parameter or member 'err_code' not described in 'process_request_key_err'
 fs/ecryptfs/keystore.c:30: warning: expecting prototype for eCryptfs(). Prototype was for process_request_key_err() instead
 fs/ecryptfs/keystore.c:558: warning: Function parameter or member 'auth_tok_key' not described in 'ecryptfs_find_auth_tok_for_sig'
 fs/ecryptfs/keystore.c:558: warning: Function parameter or member 'mount_crypt_stat' not described in 'ecryptfs_find_auth_tok_for_sig'
 fs/ecryptfs/keystore.c:558: warning: Excess function parameter 'crypt_stat' description in 'ecryptfs_find_auth_tok_for_sig'
 fs/ecryptfs/keystore.c:584: warning: cannot understand function prototype: 'struct ecryptfs_write_tag_70_packet_silly_stack '
 fs/ecryptfs/keystore.c:622: warning: Function parameter or member 'dest' not described in 'ecryptfs_write_tag_70_packet'
 fs/ecryptfs/keystore.c:622: warning: Function parameter or member 'remaining_bytes' not described in 'ecryptfs_write_tag_70_packet'
 fs/ecryptfs/keystore.c:622: warning: Function parameter or member 'packet_size' not described in 'ecryptfs_write_tag_70_packet'
 fs/ecryptfs/keystore.c:622: warning: Function parameter or member 'mount_crypt_stat' not described in 'ecryptfs_write_tag_70_packet'
 fs/ecryptfs/keystore.c:622: warning: Function parameter or member 'filename_size' not described in 'ecryptfs_write_tag_70_packet'
 fs/ecryptfs/keystore.c:622: warning: expecting prototype for write_tag_70_packet(). Prototype was for ecryptfs_write_tag_70_packet() instead
 fs/ecryptfs/keystore.c:895: warning: expecting prototype for parse_tag_70_packet(). Prototype was for ecryptfs_parse_tag_70_packet() instead

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mhalcrow@us.ibm.com>
Cc: "Michael C. Thompson" <mcthomps@us.ibm.com>
Cc: "Trevor S. Highland" <trevor.highland@gmail.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones d17074ac9e ecryptfs: inode: Help out nearly-there header and demote non-conformant ones
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/inode.c:27: warning: Function parameter or member 'dentry' not described in 'lock_parent'
 fs/ecryptfs/inode.c:27: warning: Function parameter or member 'lower_dentry' not described in 'lock_parent'
 fs/ecryptfs/inode.c:27: warning: Function parameter or member 'lower_dir' not described in 'lock_parent'
 fs/ecryptfs/inode.c:27: warning: expecting prototype for eCryptfs(). Prototype was for lock_parent() instead
 fs/ecryptfs/inode.c:211: warning: Function parameter or member 'ecryptfs_dentry' not described in 'ecryptfs_initialize_file'
 fs/ecryptfs/inode.c:211: warning: Function parameter or member 'ecryptfs_inode' not described in 'ecryptfs_initialize_file'
 fs/ecryptfs/inode.c:258: warning: Function parameter or member 'mnt_userns' not described in 'ecryptfs_create'
 fs/ecryptfs/inode.c:258: warning: Function parameter or member 'directory_inode' not described in 'ecryptfs_create'
 fs/ecryptfs/inode.c:258: warning: Function parameter or member 'ecryptfs_dentry' not described in 'ecryptfs_create'
 fs/ecryptfs/inode.c:258: warning: Function parameter or member 'excl' not described in 'ecryptfs_create'
 fs/ecryptfs/inode.c:258: warning: Excess function parameter 'dir' description in 'ecryptfs_create'
 fs/ecryptfs/inode.c:258: warning: Excess function parameter 'dentry' description in 'ecryptfs_create'
 fs/ecryptfs/inode.c:320: warning: Function parameter or member 'dentry' not described in 'ecryptfs_lookup_interpose'
 fs/ecryptfs/inode.c:320: warning: Function parameter or member 'lower_dentry' not described in 'ecryptfs_lookup_interpose'
 fs/ecryptfs/inode.c:887: warning: Function parameter or member 'mnt_userns' not described in 'ecryptfs_setattr'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: "Michael C. Thompsion" <mcthomps@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 688a9f7cd8 ecryptfs: mmap: Help out one function header and demote other abuses
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/mmap.c:26: warning: Incorrect use of kernel-doc format:  * ecryptfs_get_locked_page
 fs/ecryptfs/mmap.c:34: warning: Function parameter or member 'inode' not described in 'ecryptfs_get_locked_page'
 fs/ecryptfs/mmap.c:34: warning: Function parameter or member 'index' not described in 'ecryptfs_get_locked_page'
 fs/ecryptfs/mmap.c:34: warning: expecting prototype for eCryptfs(). Prototype was for ecryptfs_get_locked_page() instead
 fs/ecryptfs/mmap.c:52: warning: Function parameter or member 'wbc' not described in 'ecryptfs_writepage'
 fs/ecryptfs/mmap.c:98: warning: Incorrect use of kernel-doc format:  * ecryptfs_copy_up_encrypted_with_header
 fs/ecryptfs/mmap.c:110: warning: Function parameter or member 'page' not described in 'ecryptfs_copy_up_encrypted_with_header'
 fs/ecryptfs/mmap.c:110: warning: Function parameter or member 'crypt_stat' not described in 'ecryptfs_copy_up_encrypted_with_header'
 fs/ecryptfs/mmap.c:110: warning: expecting prototype for Header Extent(). Prototype was for ecryptfs_copy_up_encrypted_with_header() instead
 fs/ecryptfs/mmap.c:233: warning: wrong kernel-doc identifier on line:
 fs/ecryptfs/mmap.c:379: warning: Function parameter or member 'ecryptfs_inode' not described in 'ecryptfs_write_inode_size_to_header'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: James Morris <jamorris@linux.microsoft.com>
Cc: Tycho Andersen <tycho@tycho.pizza>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 5da877eadf ecryptfs: crypto: Supply some missing param descriptions and demote abuses
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/crypto.c:29: warning: expecting prototype for eCryptfs(). Prototype was for DECRYPT() instead
 fs/ecryptfs/crypto.c:360: warning: Function parameter or member 'crypt_stat' not described in 'lower_offset_for_page'
 fs/ecryptfs/crypto.c:360: warning: Function parameter or member 'page' not described in 'lower_offset_for_page'
 fs/ecryptfs/crypto.c:637: warning: Function parameter or member 'crypt_stat' not described in 'ecryptfs_compute_root_iv'
 fs/ecryptfs/crypto.c:1386: warning: Function parameter or member 'ecryptfs_dentry' not described in 'ecryptfs_read_metadata'
 fs/ecryptfs/crypto.c:1463: warning: Function parameter or member 'filename' not described in 'ecryptfs_encrypt_filename'
 fs/ecryptfs/crypto.c:1463: warning: Function parameter or member 'mount_crypt_stat' not described in 'ecryptfs_encrypt_filename'
 fs/ecryptfs/crypto.c:1897: warning: Function parameter or member 'encoded_name_size' not described in 'ecryptfs_encrypt_and_encode_filename'
 fs/ecryptfs/crypto.c:1897: warning: Function parameter or member 'mount_crypt_stat' not described in 'ecryptfs_encrypt_and_encode_filename'
 fs/ecryptfs/crypto.c:1897: warning: Function parameter or member 'name_size' not described in 'ecryptfs_encrypt_and_encode_filename'
 fs/ecryptfs/crypto.c:1897: warning: Excess function parameter 'crypt_stat' description in 'ecryptfs_encrypt_and_encode_filename'
 fs/ecryptfs/crypto.c:1897: warning: Excess function parameter 'length' description in 'ecryptfs_encrypt_and_encode_filename'
 fs/ecryptfs/crypto.c:2006: warning: Function parameter or member 'sb' not described in 'ecryptfs_decode_and_decrypt_filename'
 fs/ecryptfs/crypto.c:2006: warning: Excess function parameter 'ecryptfs_dir_dentry' description in 'ecryptfs_decode_and_decrypt_filename'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: "Michael C. Thompson" <mcthomps@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[tyhicks: Fix typo in ecryptfs_encrypt_and_encode_filename() func docs]
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 65bbb7b846 ecryptfs: miscdev: File headers are not good kernel-doc candidates
Supply description for the 'daemon' param too.

Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/miscdev.c:19: warning: cannot understand function prototype: 'atomic_t ecryptfs_num_miscdev_opens; '
 fs/ecryptfs/miscdev.c:323: warning: Function parameter or member 'daemon' not described in 'ecryptfs_miscdev_response'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mhalcrow@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones e24012062e ecryptfs: main: Demote a bunch of non-conformant kernel-doc headers
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/main.c:28: warning: Incorrect use of kernel-doc format:  * Module parameter that defines the ecryptfs_verbosity level.
 fs/ecryptfs/main.c:30: warning: cannot understand function prototype: 'int ecryptfs_verbosity = 0; '
 fs/ecryptfs/main.c:40: warning: cannot understand function prototype: 'unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS; '
 fs/ecryptfs/main.c:52: warning: cannot understand function prototype: 'signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ; '
 fs/ecryptfs/main.c:65: warning: cannot understand function prototype: 'unsigned int ecryptfs_number_of_users = ECRYPTFS_DEFAULT_NUM_USERS; '
 fs/ecryptfs/main.c:106: warning: Function parameter or member 'dentry' not described in 'ecryptfs_init_lower_file'
 fs/ecryptfs/main.c:106: warning: Function parameter or member 'lower_file' not described in 'ecryptfs_init_lower_file'
 fs/ecryptfs/main.c:106: warning: Excess function parameter 'ecryptfs_dentry' description in 'ecryptfs_init_lower_file'
 fs/ecryptfs/main.c:244: warning: Function parameter or member 'sbi' not described in 'ecryptfs_parse_options'
 fs/ecryptfs/main.c:244: warning: Excess function parameter 'sb' description in 'ecryptfs_parse_options'
 fs/ecryptfs/main.c:478: warning: Function parameter or member 'fs_type' not described in 'ecryptfs_mount'
 fs/ecryptfs/main.c:478: warning: Function parameter or member 'flags' not described in 'ecryptfs_mount'
 fs/ecryptfs/main.c:478: warning: expecting prototype for ecryptfs_get_sb(). Prototype was for ecryptfs_mount() instead
 fs/ecryptfs/main.c:645: warning: Function parameter or member 'vptr' not described in 'inode_info_init_once'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: James Morris <jamorris@linux.microsoft.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: "Michael C. Thompson" <mcthomps@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[tyhicks: Correct the function documentation for ecryptfs_mount()]
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 1ab8e268ea ecryptfs: messaging: Add missing param descriptions and demote abuses
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/messaging.c:15: warning: Function parameter or member 'ecryptfs_msg_ctx_free_list' not described in 'LIST_HEAD'
 fs/ecryptfs/messaging.c:15: warning: expecting prototype for eCryptfs(). Prototype was for LIST_HEAD() instead
 fs/ecryptfs/messaging.c:157: warning: Function parameter or member 'daemon' not described in 'ecryptfs_exorcise_daemon'
 fs/ecryptfs/messaging.c:207: warning: Function parameter or member 'daemon' not described in 'ecryptfs_process_response'
 fs/ecryptfs/messaging.c:207: warning: expecting prototype for ecryptfs_process_reponse(). Prototype was for ecryptfs_process_response() instead
 fs/ecryptfs/messaging.c:262: warning: Function parameter or member 'msg_type' not described in 'ecryptfs_send_message_locked'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Michael A. Halcrow" <mhalcrow@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 1c6675cafc ecryptfs: super: Fix formatting, naming and kernel-doc abuses
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/super.c:22: warning: cannot understand function prototype: 'struct kmem_cache *ecryptfs_inode_info_cache; '
 fs/ecryptfs/super.c:91: warning: Function parameter or member 'dentry' not described in 'ecryptfs_statfs'
 fs/ecryptfs/super.c:91: warning: Excess function parameter 'sb' description in 'ecryptfs_statfs'
 fs/ecryptfs/super.c:120: warning: Function parameter or member 'inode' not described in 'ecryptfs_evict_inode'
 fs/ecryptfs/super.c:133: warning: Function parameter or member 'm' not described in 'ecryptfs_show_options'
 fs/ecryptfs/super.c:133: warning: Function parameter or member 'root' not described in 'ecryptfs_show_options'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: "Michael C. Thompson" <mcthomps@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones a62187eb1f ecryptfs: file: Demote kernel-doc abuses
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/file.c:23: warning: Incorrect use of kernel-doc format:  * ecryptfs_read_update_atime
 fs/ecryptfs/file.c:34: warning: Function parameter or member 'iocb' not described in 'ecryptfs_read_update_atime'
 fs/ecryptfs/file.c:34: warning: Function parameter or member 'to' not described in 'ecryptfs_read_update_atime'
 fs/ecryptfs/file.c:34: warning: expecting prototype for eCryptfs(). Prototype was for ecryptfs_read_update_atime() instead

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mhalcrow@us.ibm.com>
Cc: "Michael C. Thompson" <mcthomps@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 446b5836af ecryptfs: kthread: Demote file header and provide description for 'cred'
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/kthread.c:16: warning: cannot understand function prototype: 'struct ecryptfs_open_req '
 fs/ecryptfs/kthread.c:120: warning: Function parameter or member 'cred' not described in 'ecryptfs_privileged_open'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 64cbb654ed ecryptfs: dentry: File headers are not good candidates for kernel-doc
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/dentry.c:19: warning: Incorrect use of kernel-doc format:  * ecryptfs_d_revalidate - revalidate an ecryptfs dentry
 fs/ecryptfs/dentry.c:32: warning: Function parameter or member 'dentry' not described in 'ecryptfs_d_revalidate'
 fs/ecryptfs/dentry.c:32: warning: Function parameter or member 'flags' not described in 'ecryptfs_d_revalidate'
 fs/ecryptfs/dentry.c:32: warning: expecting prototype for eCryptfs(). Prototype was for ecryptfs_d_revalidate() instead

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones b0cfbeff12 ecryptfs: debug: Demote a couple of kernel-doc abuses
Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/debug.c:13: warning: Incorrect use of kernel-doc format:  * ecryptfs_dump_auth_tok - debug function to print auth toks
 fs/ecryptfs/debug.c:19: warning: Function parameter or member 'auth_tok' not described in 'ecryptfs_dump_auth_tok'
 fs/ecryptfs/debug.c:19: warning: expecting prototype for eCryptfs(). Prototype was for ecryptfs_dump_auth_tok() instead

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Lee Jones 09d02efaaf ecryptfs: read_write: File headers do not make good candidates for kernel-doc
Provide missing param description for 'page_index' too.

Fixes the following W=1 kernel build warning(s):

 fs/ecryptfs/read_write.c:16: warning: Incorrect use of kernel-doc format:  * ecryptfs_write_lower
 fs/ecryptfs/read_write.c:29: warning: Function parameter or member 'ecryptfs_inode' not described in 'ecryptfs_write_lower'
 fs/ecryptfs/read_write.c:29: warning: Function parameter or member 'data' not described in 'ecryptfs_write_lower'
 fs/ecryptfs/read_write.c:29: warning: Function parameter or member 'offset' not described in 'ecryptfs_write_lower'
 fs/ecryptfs/read_write.c:29: warning: Function parameter or member 'size' not described in 'ecryptfs_write_lower'
 fs/ecryptfs/read_write.c:29: warning: expecting prototype for eCryptfs(). Prototype was for ecryptfs_write_lower() instead
 fs/ecryptfs/read_write.c:248: warning: Function parameter or member 'page_index' not described in 'ecryptfs_read_lower_page_segment'

Cc: Tyler Hicks <code@tyhicks.com>
Cc: "Michael A. Halcrow" <mahalcro@us.ibm.com>
Cc: ecryptfs@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-04-19 04:42:13 +00:00
Tyler Hicks b7f8f25989 Linux 5.12-rc7
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmBzdS0eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGDdAIAIpKH/tAHhH7s7QH
 m5ewgE8foP7M5Ue9fp3+JmbtaYSzhCAMcKhqGtat/zk5PvA9AoYCDXrTetfYtBHh
 LUOmhL9hcKItNobfkYBok6BiFjGUEL3HMqz5w+MUsMwnXIc4RXqfJmsQ932z9Kxf
 yDwe6ehIzJVrQLI/C0mTamYRHu2aiZ1VWzhKuT493rLeg0R2odCCIClPN+/QvCwb
 8/sk6l1c8eOUYYMUzKFZifaZGb12qDjRt4pZmk51aMTzg0WCpElJG+7Uqr4QQhZP
 p6xeNuUQq6WwxtlDkmo79Uzkrurb5tN2/hZ1RcJhs3EdHfpR0MjIyH3Znnb31gnu
 39VjHhg=
 =4KP/
 -----END PGP SIGNATURE-----

Merge tag 'v5.12-rc7' into ecryptfs/next

Required to pick up idmapped mount changes which changed some function
parameters.
2021-04-19 04:39:17 +00:00
Miklos Szeredi 97e2dee975 ecryptfs: stack fileattr ops
Add stacking for the fileattr operations.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Tyler Hicks <code@tyhicks.com>
2021-04-12 15:04:29 +02:00
Al Viro 9d786beb6f ecryptfs: ecryptfs_dentry_info->crypt_stat is never used
... and never had anything non-NULL stored into it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-20 17:46:44 -04:00
Al Viro 483bc7e82c ecryptfs: get rid of unused accessors
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-20 17:46:42 -04:00
Al Viro b2648d512e ecryptfs: saner API for lock_parent()
Switch all users of lock_parent() to the approach used by ->unlink()
and ->rmdir() - instead of playing with dget_parent() of underlying
dentry of child,
	* start with ecryptfs dentry of child.
	* find underlying dentries for that dentry and its parent
(which is stable, since the parent directory in upper layer is
held at least shared).  No need to pin them, they are already pinned
by ecryptfs dentries.
	* lock the inode of undelying directory of parent
	* check if it's the parent of underlying dentry of child.
->d_parent of underlying dentry of child might be unstable.  However,
result of its comparison with underlying dentry of parent *is* stable now.

Turn that into replacement of lock_parent(), convert the existing callers
of lock_parent() to that, along with ecryptfs_unlink() and ecryptfs_rmdir().

Callers need only the underlying dentry of child and inode of underlying
dentry of parent, so lock_parent() passes those to the caller now.
Note that underlying directory is locked in any case, success or failure.

That approach does not need a primitive for unlocking - we hadn't grabbed
any dentry references, so all we need is to unlock the underlying directory
inode.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-20 17:46:37 -04:00
Al Viro 4313e35233 ecryptfs: get rid of pointless dget/dput in ->symlink() and ->link()
calls in ->unlink(), ->rmdir() and ->rename() make sense - we want
to prevent the underlying dentries going negative there.  In
->symlink() and ->link() they are absolutely pointless.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:24:10 -05:00
Linus Torvalds 7d6beb71da idmapped-mounts-v5.12
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCYCegywAKCRCRxhvAZXjc
 ouJ6AQDlf+7jCQlQdeKKoN9QDFfMzG1ooemat36EpRRTONaGuAD8D9A4sUsG4+5f
 4IU5Lj9oY4DEmF8HenbWK2ZHsesL2Qg=
 =yPaw
 -----END PGP SIGNATURE-----

Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull idmapped mounts from Christian Brauner:
 "This introduces idmapped mounts which has been in the making for some
  time. Simply put, different mounts can expose the same file or
  directory with different ownership. This initial implementation comes
  with ports for fat, ext4 and with Christoph's port for xfs with more
  filesystems being actively worked on by independent people and
  maintainers.

  Idmapping mounts handle a wide range of long standing use-cases. Here
  are just a few:

   - Idmapped mounts make it possible to easily share files between
     multiple users or multiple machines especially in complex
     scenarios. For example, idmapped mounts will be used in the
     implementation of portable home directories in
     systemd-homed.service(8) where they allow users to move their home
     directory to an external storage device and use it on multiple
     computers where they are assigned different uids and gids. This
     effectively makes it possible to assign random uids and gids at
     login time.

   - It is possible to share files from the host with unprivileged
     containers without having to change ownership permanently through
     chown(2).

   - It is possible to idmap a container's rootfs and without having to
     mangle every file. For example, Chromebooks use it to share the
     user's Download folder with their unprivileged containers in their
     Linux subsystem.

   - It is possible to share files between containers with
     non-overlapping idmappings.

   - Filesystem that lack a proper concept of ownership such as fat can
     use idmapped mounts to implement discretionary access (DAC)
     permission checking.

   - They allow users to efficiently changing ownership on a per-mount
     basis without having to (recursively) chown(2) all files. In
     contrast to chown (2) changing ownership of large sets of files is
     instantenous with idmapped mounts. This is especially useful when
     ownership of a whole root filesystem of a virtual machine or
     container is changed. With idmapped mounts a single syscall
     mount_setattr syscall will be sufficient to change the ownership of
     all files.

   - Idmapped mounts always take the current ownership into account as
     idmappings specify what a given uid or gid is supposed to be mapped
     to. This contrasts with the chown(2) syscall which cannot by itself
     take the current ownership of the files it changes into account. It
     simply changes the ownership to the specified uid and gid. This is
     especially problematic when recursively chown(2)ing a large set of
     files which is commong with the aforementioned portable home
     directory and container and vm scenario.

   - Idmapped mounts allow to change ownership locally, restricting it
     to specific mounts, and temporarily as the ownership changes only
     apply as long as the mount exists.

  Several userspace projects have either already put up patches and
  pull-requests for this feature or will do so should you decide to pull
  this:

   - systemd: In a wide variety of scenarios but especially right away
     in their implementation of portable home directories.

         https://systemd.io/HOME_DIRECTORY/

   - container runtimes: containerd, runC, LXD:To share data between
     host and unprivileged containers, unprivileged and privileged
     containers, etc. The pull request for idmapped mounts support in
     containerd, the default Kubernetes runtime is already up for quite
     a while now: https://github.com/containerd/containerd/pull/4734

   - The virtio-fs developers and several users have expressed interest
     in using this feature with virtual machines once virtio-fs is
     ported.

   - ChromeOS: Sharing host-directories with unprivileged containers.

  I've tightly synced with all those projects and all of those listed
  here have also expressed their need/desire for this feature on the
  mailing list. For more info on how people use this there's a bunch of
  talks about this too. Here's just two recent ones:

      https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf
      https://fosdem.org/2021/schedule/event/containers_idmap/

  This comes with an extensive xfstests suite covering both ext4 and
  xfs:

      https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts

  It covers truncation, creation, opening, xattrs, vfscaps, setid
  execution, setgid inheritance and more both with idmapped and
  non-idmapped mounts. It already helped to discover an unrelated xfs
  setgid inheritance bug which has since been fixed in mainline. It will
  be sent for inclusion with the xfstests project should you decide to
  merge this.

  In order to support per-mount idmappings vfsmounts are marked with
  user namespaces. The idmapping of the user namespace will be used to
  map the ids of vfs objects when they are accessed through that mount.
  By default all vfsmounts are marked with the initial user namespace.
  The initial user namespace is used to indicate that a mount is not
  idmapped. All operations behave as before and this is verified in the
  testsuite.

  Based on prior discussions we want to attach the whole user namespace
  and not just a dedicated idmapping struct. This allows us to reuse all
  the helpers that already exist for dealing with idmappings instead of
  introducing a whole new range of helpers. In addition, if we decide in
  the future that we are confident enough to enable unprivileged users
  to setup idmapped mounts the permission checking can take into account
  whether the caller is privileged in the user namespace the mount is
  currently marked with.

  The user namespace the mount will be marked with can be specified by
  passing a file descriptor refering to the user namespace as an
  argument to the new mount_setattr() syscall together with the new
  MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
  of extensibility.

  The following conditions must be met in order to create an idmapped
  mount:

   - The caller must currently have the CAP_SYS_ADMIN capability in the
     user namespace the underlying filesystem has been mounted in.

   - The underlying filesystem must support idmapped mounts.

   - The mount must not already be idmapped. This also implies that the
     idmapping of a mount cannot be altered once it has been idmapped.

   - The mount must be a detached/anonymous mount, i.e. it must have
     been created by calling open_tree() with the OPEN_TREE_CLONE flag
     and it must not already have been visible in the filesystem.

  The last two points guarantee easier semantics for userspace and the
  kernel and make the implementation significantly simpler.

  By default vfsmounts are marked with the initial user namespace and no
  behavioral or performance changes are observed.

  The manpage with a detailed description can be found here:

      1d7b902e28

  In order to support idmapped mounts, filesystems need to be changed
  and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
  patches to convert individual filesystem are not very large or
  complicated overall as can be seen from the included fat, ext4, and
  xfs ports. Patches for other filesystems are actively worked on and
  will be sent out separately. The xfstestsuite can be used to verify
  that port has been done correctly.

  The mount_setattr() syscall is motivated independent of the idmapped
  mounts patches and it's been around since July 2019. One of the most
  valuable features of the new mount api is the ability to perform
  mounts based on file descriptors only.

  Together with the lookup restrictions available in the openat2()
  RESOLVE_* flag namespace which we added in v5.6 this is the first time
  we are close to hardened and race-free (e.g. symlinks) mounting and
  path resolution.

  While userspace has started porting to the new mount api to mount
  proper filesystems and create new bind-mounts it is currently not
  possible to change mount options of an already existing bind mount in
  the new mount api since the mount_setattr() syscall is missing.

  With the addition of the mount_setattr() syscall we remove this last
  restriction and userspace can now fully port to the new mount api,
  covering every use-case the old mount api could. We also add the
  crucial ability to recursively change mount options for a whole mount
  tree, both removing and adding mount options at the same time. This
  syscall has been requested multiple times by various people and
  projects.

  There is a simple tool available at

      https://github.com/brauner/mount-idmapped

  that allows to create idmapped mounts so people can play with this
  patch series. I'll add support for the regular mount binary should you
  decide to pull this in the following weeks:

  Here's an example to a simple idmapped mount of another user's home
  directory:

	u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt

	u1001@f2-vm:/$ ls -al /home/ubuntu/
	total 28
	drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
	drwxr-xr-x 4 root   root   4096 Oct 28 04:00 ..
	-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
	-rw-r--r-- 1 ubuntu ubuntu  220 Feb 25  2020 .bash_logout
	-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25  2020 .bashrc
	-rw-r--r-- 1 ubuntu ubuntu  807 Feb 25  2020 .profile
	-rw-r--r-- 1 ubuntu ubuntu    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ ls -al /mnt/
	total 28
	drwxr-xr-x  2 u1001 u1001 4096 Oct 28 22:07 .
	drwxr-xr-x 29 root  root  4096 Oct 28 22:01 ..
	-rw-------  1 u1001 u1001 3154 Oct 28 22:12 .bash_history
	-rw-r--r--  1 u1001 u1001  220 Feb 25  2020 .bash_logout
	-rw-r--r--  1 u1001 u1001 3771 Feb 25  2020 .bashrc
	-rw-r--r--  1 u1001 u1001  807 Feb 25  2020 .profile
	-rw-r--r--  1 u1001 u1001    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw-------  1 u1001 u1001 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ touch /mnt/my-file

	u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file

	u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file

	u1001@f2-vm:/$ ls -al /mnt/my-file
	-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file

	u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
	-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file

	u1001@f2-vm:/$ getfacl /mnt/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: mnt/my-file
	# owner: u1001
	# group: u1001
	user::rw-
	user:u1001:rwx
	group::rw-
	mask::rwx
	other::r--

	u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: home/ubuntu/my-file
	# owner: ubuntu
	# group: ubuntu
	user::rw-
	user:ubuntu:rwx
	group::rw-
	mask::rwx
	other::r--"

* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
  xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
  xfs: support idmapped mounts
  ext4: support idmapped mounts
  fat: handle idmapped mounts
  tests: add mount_setattr() selftests
  fs: introduce MOUNT_ATTR_IDMAP
  fs: add mount_setattr()
  fs: add attr_flags_to_mnt_flags helper
  fs: split out functions to hold writers
  namespace: only take read lock in do_reconfigure_mnt()
  mount: make {lock,unlock}_mount_hash() static
  namespace: take lock_mount_hash() directly when changing flags
  nfs: do not export idmapped mounts
  overlayfs: do not mount on top of idmapped mounts
  ecryptfs: do not mount on top of idmapped mounts
  ima: handle idmapped mounts
  apparmor: handle idmapped mounts
  fs: make helpers idmap mount aware
  exec: handle idmapped mounts
  would_dump: handle idmapped mounts
  ...
2021-02-23 13:39:45 -08:00
Zheng Yongjun 902af36994 ecryptfs: use DEFINE_MUTEX() for mutex lock
mutex lock can be initialized automatically with DEFINE_MUTEX()
rather than explicitly calling mutex_init().

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-01-30 17:09:05 +00:00
Tom Rix d0eb2d867c eCryptfs: add a semicolon
Function like macros should have a semicolon.

Signed-off-by: Tom Rix <trix@redhat.com>
[tyhicks: Remove the trailing semicolin from the macro's definition, as
          suggested by Joe Perches]
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-01-30 17:09:05 +00:00
Miklos Szeredi 0b964446c6 ecryptfs: fix uid translation for setxattr on security.capability
Prior to commit 7c03e2cda4 ("vfs: move cap_convert_nscap() call into
vfs_setxattr()") the translation of nscap->rootid did not take stacked
filesystems (overlayfs and ecryptfs) into account.

That patch fixed the overlay case, but made the ecryptfs case worse.

Restore old the behavior for ecryptfs that existed before the overlayfs
fix.  This does not fix ecryptfs's handling of complex user namespace
setups, but it does make sure existing setups don't regress.

Reported-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tyler Hicks <code@tyhicks.com>
Fixes: 7c03e2cda4 ("vfs: move cap_convert_nscap() call into vfs_setxattr()")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2021-01-26 01:47:14 +00:00
Christian Brauner 0f16ff0f54
ecryptfs: do not mount on top of idmapped mounts
Prevent ecryptfs from being mounted on top of idmapped mounts.
Stacking filesystems need to be prevented from being mounted on top of
idmapped mounts until they have have been converted to handle this.

Link: https://lore.kernel.org/r/20210121131959.646623-28-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner 549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner 6521f89170
namei: prepare for idmapped mounts
The various vfs_*() helpers are called by filesystems or by the vfs
itself to perform core operations such as create, link, mkdir, mknod, rename,
rmdir, tmpfile and unlink. Enable them to handle idmapped mounts. If the
inode is accessed through an idmapped mount map it into the
mount's user namespace and pass it down. Afterwards the checks and
operations are identical to non-idmapped mounts. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-15-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:18 +01:00
Christian Brauner 9fe6145097
namei: introduce struct renamedata
In order to handle idmapped mounts we will extend the vfs rename helper
to take two new arguments in follow up patches. Since this operations
already takes a bunch of arguments add a simple struct renamedata and
make the current helper use it before we extend it.

Link: https://lore.kernel.org/r/20210121131959.646623-14-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:18 +01:00
Christian Brauner 0d56a4518d
stat: handle idmapped mounts
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Tycho Andersen c7c7a1a18a
xattr: handle idmapped mounts
When interacting with extended attributes the vfs verifies that the
caller is privileged over the inode with which the extended attribute is
associated. For posix access and posix default extended attributes a uid
or gid can be stored on-disk. Let the functions handle posix extended
attributes on idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user
namespace. Afterwards the checks are identical to non-idmapped mounts.
This has no effect for e.g. security xattrs since they don't store uids
or gids and don't perform permission checks on them like posix acls do.

Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner e65ce2a50c
acl: handle idmapped mounts
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.

The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.

In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.

Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner 2f221d6f7b
attr: handle idmapped mounts
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.

Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Christian Brauner 47291baa8d
namei: make permission helpers idmapped mount aware
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Waiman Long 453431a549 mm, treewide: rename kzfree() to kfree_sensitive()
As said by Linus:

  A symmetric naming is only helpful if it implies symmetries in use.
  Otherwise it's actively misleading.

  In "kzalloc()", the z is meaningful and an important part of what the
  caller wants.

  In "kzfree()", the z is actively detrimental, because maybe in the
  future we really _might_ want to use that "memfill(0xdeadbeef)" or
  something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

  git grep -w --name-only kzfree |\
  xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
Linus Torvalds b23c4771ff A fair amount of stuff this time around, dominated by yet another massive
set from Mauro toward the completion of the RST conversion.  I *really*
 hope we are getting close to the end of this.  Meanwhile, those patches
 reach pretty far afield to update document references around the tree;
 there should be no actual code changes there.  There will be, alas, more of
 the usual trivial merge conflicts.
 
 Beyond that we have more translations, improvements to the sphinx
 scripting, a number of additions to the sysctl documentation, and lots of
 fixes.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl7VId8PHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5Yq/gH/iaDgirQZV6UZ2v9sfwQNYolNpf2sKAuOZjd
 bPFB7WJoMQbKwQEvYrAUL2+5zPOcLYuIfzyOfo1BV1py+EyKbACcKjI4AedxfJF7
 +NchmOBhlEqmEhzx2U08HRc4/8J223WG17fJRVsV3p+opJySexSFeQucfOciX5NR
 RUCxweWWyg/FgyqjkyMMTtsePqZPmcT5dWTlVXISlbWzcv5NFhuJXnSrw8Sfzcmm
 SJMzqItv3O+CabnKQ8kMLV2PozXTMfjeWH47ZUK0Y8/8PP9+cvqwFzZ0UDQJ1Xaz
 oyW/TqmunaXhfMsMFeFGSwtfgwRHvXdxkQdtwNHvo1dV4dzTvDw=
 =fDC/
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.8' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
Eric Biggers 1979811388 ecryptfs: use crypto_shash_tfm_digest()
Instead of manually allocating a 'struct shash_desc' on the stack and
calling crypto_shash_digest(), switch to using the new helper function
crypto_shash_tfm_digest() which does this for us.

Cc: ecryptfs@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-05-08 15:32:15 +10:00
Mauro Carvalho Chehab 0c1bc6b845 docs: filesystems: fix renamed references
Some filesystem references got broken by a previous patch
series I submitted. Address those.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig
Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:22 -06:00
Linus Torvalds b1da3acc78 eCryptfs fixes for 5.6-rc3
- Downgrade the eCryptfs maintenance status to "Odd Fixes"
 - Change my email address
 - Fix a couple memory leaks in error paths
 - Stability improvement to avoid a needless BUG_ON()
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEKvuQkp28KvPJn/fVfL7QslYSS/0FAl5K+wkACgkQfL7QslYS
 S/1vrA//TIaQWadfWeXbdd8Kj+zEsd6BDZEiGq56w5WtuYe+XcAKdXITBLXXVZR1
 /MHR4h16BpkmyRbKojvGjqECLf8W8XeZC30gEXJEM7PVbFvLvM92ZKUT/K3ax7Tt
 HBQs8L0MM2BDWFDyfQ9vWnPakIvy1pHS4iHQeJgtcBfqcMS+u6fYmpoCIbWZ9UfA
 7ilS931CjFxgRvKdwMRp4C08fUs7awqYcZxkDMjp3uAOSp0YFtp3/EiPrNAe1+ot
 /PuwzV69a7raqRurdBUApj9QMY1VmKheY80Wgl4C0aS5lc+JUiOpclKDRW174W51
 UFI9CanRcqNig7KY+eTenJWDS8l9nEK40nQWKHQZ5JT+kitWMyvjrXh6MwIRFvKE
 N+7gSWZWumQknKSg3y1AVkEZK+mHw7lRJ8ziLCxrR28EkS3TTvw2mpp80ed0jC/v
 SCUwj4rqP1l7wR7xa4vlYSXOLznK/DRBSrud7bbQlZOTjVXZAeNv2LOe8qLu8C0b
 j+/Mhf6OKUd5c7Pjl+7YD1/DcKsUlayyVn0k2HX/V17QK1a5Kp5R+6mbvyFclq1T
 nQTgu5prq7BiS49GGY/JePO0wKCi2+A3T87rj2Y1yfGjYNgcR/zsQa2LuPtP92Tt
 5aAHpP+lC9CoJohYjM/cRncq1rsOnBchQRz+i/VgVtUqJ9vfgXM=
 =kXnY
 -----END PGP SIGNATURE-----

Merge tag 'ecryptfs-5.6-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull eCryptfs fixes from Tyler Hicks:

 - downgrade the eCryptfs maintenance status to "Odd Fixes"

 - change my email address

 - fix a couple memory leaks in error paths

 - stability improvement to avoid a needless BUG_ON()

* tag 'ecryptfs-5.6-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  ecryptfs: replace BUG_ON with error handling code
  eCryptfs: Replace deactivated email address
  MAINTAINERS: eCryptfs: Update maintainer address and downgrade status
  ecryptfs: fix a memory leak bug in ecryptfs_init_messaging()
  ecryptfs: fix a memory leak bug in parse_tag_1_packet()
2020-02-17 21:08:37 -08:00
Aditya Pakki 2c2a7552dd ecryptfs: replace BUG_ON with error handling code
In crypt_scatterlist, if the crypt_stat argument is not set up
correctly, the kernel crashes. Instead, by returning an error code
upstream, the error is handled safely.

The issue is detected via a static analysis tool written by us.

Fixes: 237fead619 (ecryptfs: fs/Makefile and fs/Kconfig)
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2020-02-14 20:07:46 +00:00
Tyler Hicks f8e48a8408 eCryptfs: Replace deactivated email address
Replace a recently deactived email address with one that I'll be able to
personally control and keep alive.

Signed-off-by: Tyler Hicks <code@tyhicks.com>
2020-02-14 20:07:31 +00:00
Linus Torvalds 236f453294 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:

 - bmap series from cmaiolino

 - getting rid of convolutions in copy_mount_options() (use a couple of
   copy_from_user() instead of the __get_user() crap)

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  saner copy_mount_options()
  fibmap: Reject negative block numbers
  fibmap: Use bmap instead of ->bmap method in ioctl_fibmap
  ecryptfs: drop direct calls to ->bmap
  cachefiles: drop direct usage of ->bmap method.
  fs: Enable bmap() function to properly return errors
2020-02-08 13:04:49 -08:00
Carlos Maiolino 569d2056de ecryptfs: drop direct calls to ->bmap
Replace direct ->bmap calls by bmap() method.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-03 08:05:57 -05:00
Eric Biggers 9ac0d13693 crypto: skcipher - remove crypto_skcipher::keysize
Due to the removal of the blkcipher and ablkcipher algorithm types,
crypto_skcipher::keysize is now redundant since it always equals
crypto_skcipher_alg(tfm)->max_keysize.

Remove it and update crypto_skcipher_default_keysize() accordingly.

Also rename crypto_skcipher_default_keysize() to
crypto_skcipher_max_keysize() to clarify that it specifically returns
the maximum key size, not some unspecified "default".

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11 16:36:56 +08:00
Linus Torvalds 0da522107e compat_ioctl: remove most of fs/compat_ioctl.c
As part of the cleanup of some remaining y2038 issues, I came to
 fs/compat_ioctl.c, which still has a couple of commands that need support
 for time64_t.
 
 In completely unrelated work, I spent time on cleaning up parts of this
 file in the past, moving things out into drivers instead.
 
 After Al Viro reviewed an earlier version of this series and did a lot
 more of that cleanup, I decided to try to completely eliminate the rest
 of it and move it all into drivers.
 
 This series incorporates some of Al's work and many patches of my own,
 but in the end stops short of actually removing the last part, which is
 the scsi ioctl handlers. I have patches for those as well, but they need
 more testing or possibly a rewrite.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJdsHCdAAoJEJpsee/mABjZtYkP/1JGl3jFv3Iq/5BCdPkaePP1
 RtMJRNfURgK3GeuHUui330PvVjI/pLWXU/VXMK2MPTASpJLzYz3uCaZrpVWEMpDZ
 +ImzGmgJkITlW1uWU3zOcQhOxTyb1hCZ0Ci+2xn9QAmyOL7prXoXCXDWv3h6iyiF
 lwG+nW+HNtyx41YG+9bRfKNoG0ZJ+nkJ70BV6u0acQHXWn7Xuupa9YUmBL87hxAL
 6dlJfLTJg6q8QSv/Q6LxslfWk2Ti8OOJZOwtFM5R8Bgl0iUcvshiRCKfv/3t9jXD
 dJNvF1uq8z+gracWK49Qsfq5dnZ2ZxHFUo9u0NjbCrxNvWH/sdvhbaUBuJI75seH
 VIznCkdxFhrqitJJ8KmxANxG08u+9zSKjSlxG2SmlA4qFx/AoStoHwQXcogJscNb
 YIXYKmWBvwPzYu09QFAXdHFPmZvp/3HhMWU6o92lvDhsDwzkSGt3XKhCJea4DCaT
 m+oCcoACqSWhMwdbJOEFofSub4bY43s5iaYuKes+c8O261/Dwg6v/pgIVez9mxXm
 TBnvCsotq5m8wbwzv99eFqGeJH8zpDHrXxEtRR5KQqMqjLq/OQVaEzmpHZTEuK7n
 e/V/PAKo2/V63g4k6GApQXDxnjwT+m0aWToWoeEzPYXS6KmtWC91r4bWtslu3rdl
 bN65armTm7bFFR32Avnu
 =lgCl
 -----END PGP SIGNATURE-----

Merge tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
 "As part of the cleanup of some remaining y2038 issues, I came to
  fs/compat_ioctl.c, which still has a couple of commands that need
  support for time64_t.

  In completely unrelated work, I spent time on cleaning up parts of
  this file in the past, moving things out into drivers instead.

  After Al Viro reviewed an earlier version of this series and did a lot
  more of that cleanup, I decided to try to completely eliminate the
  rest of it and move it all into drivers.

  This series incorporates some of Al's work and many patches of my own,
  but in the end stops short of actually removing the last part, which
  is the scsi ioctl handlers. I have patches for those as well, but they
  need more testing or possibly a rewrite"

* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
  scsi: sd: enable compat ioctls for sed-opal
  pktcdvd: add compat_ioctl handler
  compat_ioctl: move SG_GET_REQUEST_TABLE handling
  compat_ioctl: ppp: move simple commands into ppp_generic.c
  compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
  compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
  compat_ioctl: unify copy-in of ppp filters
  tty: handle compat PPP ioctls
  compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
  compat_ioctl: handle SIOCOUTQNSD
  af_unix: add compat_ioctl support
  compat_ioctl: reimplement SG_IO handling
  compat_ioctl: move WDIOC handling into wdt drivers
  fs: compat_ioctl: move FITRIM emulation into file systems
  gfs2: add compat_ioctl support
  compat_ioctl: remove unused convert_in_user macro
  compat_ioctl: remove last RAID handling code
  compat_ioctl: remove /dev/raw ioctl translation
  compat_ioctl: remove PCI ioctl translation
  compat_ioctl: remove joystick ioctl translation
  ...
2019-12-01 13:46:15 -08:00
Al Viro 762c69685f ecryptfs_lookup_interpose(): lower_dentry->d_parent is not stable either
We need to get the underlying dentry of parent; sure, absent the races
it is the parent of underlying dentry, but there's nothing to prevent
losing a timeslice to preemtion in the middle of evaluation of
lower_dentry->d_parent->d_inode, having another process move lower_dentry
around and have its (ex)parent not pinned anymore and freed on memory
pressure.  Then we regain CPU and try to fetch ->d_inode from memory
that is freed by that point.

dentry->d_parent *is* stable here - it's an argument of ->lookup() and
we are guaranteed that it won't be moved anywhere until we feed it
to d_add/d_splice_alias.  So we safely go that way to get to its
underlying dentry.

Cc: stable@vger.kernel.org # since 2009 or so
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-11-10 11:57:45 -05:00