kernel/git/stable/linux.git/fs/f2fs/dir.c, branch linux-4.9.y

f2fs: check if file namelen exceeds max value

2020-08-21T09:01:48+00:00

[ Upstream commit 720db068634c91553a8e1d9a0fcd8c7050e06d2b ] Dentry bitmap is not enough to detect incorrect dentries. So this patch also checks the namelen value of a dentry. Signed-off-by: Gong Chen Signed-off-by: Sheng Yong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: check memory boundary by insane namelen

2020-08-21T09:01:48+00:00

[ Upstream commit 4e240d1bab1ead280ddf5eb05058dba6bbd57d10 ] If namelen is corrupted to have very long value, fill_dentries can copy wrong memory area. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to spread clear_cold_data()

2019-11-28T17:28:35+00:00

[ Upstream commit 2baf07818549c8bb8d7b3437e889b86eab56d38e ] We need to drop PG_checked flag on page as well when we clear PG_uptodate flag, in order to avoid treating the page as GCing one later. Signed-off-by: Weichao Guo Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix multiple f2fs_add_link() having same name for inline dentry

2018-11-10T15:42:45+00:00

[ Upstream commit d3bb910c15d75ee3340311c64a1c05985bb663a3 ] Commit 88c5c13a5027 (f2fs: fix multiple f2fs_add_link() calls having same name) does not cover the scenario where inline dentry is enabled. In that case, F2FS_I(dir)->task will be NULL, and __f2fs_add_link will lookup dentries one more time. This patch fixes it by moving the assigment of current task to a upper level to cover both normal and inline dentry. Cc: Fixes: 88c5c13a5027 (f2fs: fix multiple f2fs_add_link() calls having same name) Signed-off-by: Sheng Yong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

fscrypt: use ENOKEY when file cannot be created w/o key

2017-11-30T08:39:11+00:00

[ Upstream commit 54475f531bb8d7078f63c159e5e0615d486c498c ] As part of an effort to clean up fscrypt-related error codes, make attempting to create a file in an encrypted directory that hasn't been "unlocked" fail with ENOKEY. Previously, several error codes were used for this case, including ENOENT, EACCES, and EPERM, and they were not consistent between and within filesystems. ENOKEY is a better choice because it expresses that the failure is due to lacking the encryption key. It also matches the error code returned when trying to open an encrypted regular file without the key. I am not aware of any users who might be relying on the previous inconsistent error codes, which were never documented anywhere. This failure case will be exercised by an xfstest. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

fscrypt: avoid collisions when presenting long encrypted filenames

2017-05-25T13:44:38+00:00

commit 6b06cdee81d68a8a829ad8e8d0f31d6836744af9 upstream. When accessing an encrypted directory without the key, userspace must operate on filenames derived from the ciphertext names, which contain arbitrary bytes. Since we must support filenames as long as NAME_MAX, we can't always just base64-encode the ciphertext, since that may make it too long. Currently, this is solved by presenting long names in an abbreviated form containing any needed filesystem-specific hashes (e.g. to identify a directory block), then the last 16 bytes of ciphertext. This needs to be sufficient to identify the actual name on lookup. However, there is a bug. It seems to have been assumed that due to the use of a CBC (ciphertext block chaining)-based encryption mode, the last 16 bytes (i.e. the AES block size) of ciphertext would depend on the full plaintext, preventing collisions. However, we actually use CBC with ciphertext stealing (CTS), which handles the last two blocks specially, causing them to appear "flipped". Thus, it's actually the second-to-last block which depends on the full plaintext. This caused long filenames that differ only near the end of their plaintexts to, when observed without the key, point to the wrong inode and be undeletable. For example, with ext4: # echo pass | e4crypt add_key -p 16 edir/ # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l 100000 # sync # echo 3 > /proc/sys/vm/drop_caches # keyctl new_session # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l 2004 # rm -rf edir/ rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning ... To fix this, when presenting long encrypted filenames, encode the second-to-last block of ciphertext rather than the last 16 bytes. Although it would be nice to solve this without depending on a specific encryption mode, that would mean doing a cryptographic hash like SHA-256 which would be much less efficient. This way is sufficient for now, and it's still compatible with encryption modes like HEH which are strong pseudorandom permutations. Also, changing the presented names is still allowed at any time because they are only provided to allow applications to do things like delete encrypted directories. They're not designed to be used to persistently identify files --- which would be hard to do anyway, given that they're encrypted after all. For ease of backports, this patch only makes the minimal fix to both ext4 and f2fs. It leaves ubifs as-is, since ubifs doesn't compare the ciphertext block yet. Follow-on patches will clean things up properly and make the filesystems use a shared helper function. Fixes: 5de0b4d0cd15 ("ext4 crypto: simplify and speed up filename encryption") Reported-by: Gwendal Grignou Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

f2fs: check entire encrypted bigname when finding a dentry

2017-05-25T13:44:38+00:00

commit 6332cd32c8290a80e929fc044dc5bdba77396e33 upstream. If user has no key under an encrypted dir, fscrypt gives digested dentries. Previously, when looking up a dentry, f2fs only checks its hash value with first 4 bytes of the digested dentry, which didn't handle hash collisions fully. This patch enhances to check entire dentry bytes likewise ext4. Eric reported how to reproduce this issue by: # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch # find edir -type f | xargs stat -c %i | sort | uniq | wc -l 100000 # sync # echo 3 > /proc/sys/vm/drop_caches # keyctl new_session # find edir -type f | xargs stat -c %i | sort | uniq | wc -l 99999 Cc: Reported-by: Eric Biggers Signed-off-by: Jaegeuk Kim (fixed f2fs_dentry_hash() to work even when the hash is 0) Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

f2fs: fix multiple f2fs_add_link() calls having same name

2017-03-12T05:41:51+00:00

commit 88c5c13a5027b36d914536fdba23f069d7067204 upstream. It turns out a stakable filesystem like sdcardfs in AOSP can trigger multiple vfs_create() to lower filesystem. In that case, f2fs will add multiple dentries having same name which breaks filesystem consistency. Until upper layer fixes, let's work around by f2fs, which shows actually not much performance regression. Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-10-11T03:16:43+00:00

Pull more vfs updates from Al Viro: ">rename2() work from Miklos + current_time() from Deepa" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Replace current_fs_time() with current_time() fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps fs: Replace CURRENT_TIME with current_time() for inode timestamps fs: proc: Delete inode time initializations in proc_alloc_inode() vfs: Add current_time() api vfs: add note about i_op->rename changes to porting fs: rename "rename2" i_op to "rename" vfs: remove unused i_op->rename fs: make remaining filesystems use .rename2 libfs: support RENAME_NOREPLACE in simple_rename() fs: support RENAME_NOREPLACE for local filesystems ncpfs: fix unused variable warning

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2016-10-07T22:15:33+00:00

Pull ext4 updates from Ted Ts'o: "Lots of bug fixes and cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (40 commits) ext4: remove unused variable ext4: use journal inode to determine journal overhead ext4: create function to read journal inode ext4: unmap metadata when zeroing blocks ext4: remove plugging from ext4_file_write_iter() ext4: allow unlocked direct IO when pages are cached ext4: require encryption feature for EXT4_IOC_SET_ENCRYPTION_POLICY fscrypto: use standard macros to compute length of fname ciphertext ext4: do not unnecessarily null-terminate encrypted symlink data ext4: release bh in make_indexed_dir ext4: Allow parallel DIO reads ext4: allow DAX writeback for hole punch jbd2: fix lockdep annotation in add_transaction_credits() blockgroup_lock.h: simplify definition of NR_BG_LOCKS blockgroup_lock.h: remove debris from bgl_lock_ptr() conversion fscrypto: make filename crypto functions return 0 on success fscrypto: rename completion callbacks to reflect usage fscrypto: remove unnecessary includes fscrypto: improved validation when loading inode encryption metadata ext4: fix memory leak when symlink decryption fails ...