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* Merge tag 'fscrypt_for_linus' of ↵Linus Torvalds2018-02-041-43/+15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Refactor support for encrypted symlinks to move common code to fscrypt" Ted also points out about the merge: "This makes the f2fs symlink code use the fscrypt_encrypt_symlink() from the fscrypt tree. This will end up dropping the kzalloc() -> f2fs_kzalloc() change, which means the fscrypt-specific allocation won't get tested by f2fs's kmalloc error injection system; which is fine" * tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: (26 commits) fscrypt: fix build with pre-4.6 gcc versions fscrypt: remove 'ci' parameter from fscrypt_put_encryption_info() fscrypt: document symlink length restriction fscrypt: fix up fscrypt_fname_encrypted_size() for internal use fscrypt: define fscrypt_fname_alloc_buffer() to be for presented names fscrypt: calculate NUL-padding length in one place only fscrypt: move fscrypt_symlink_data to fscrypt_private.h fscrypt: remove fscrypt_fname_usr_to_disk() ubifs: switch to fscrypt_get_symlink() ubifs: switch to fscrypt ->symlink() helper functions ubifs: free the encrypted symlink target f2fs: switch to fscrypt_get_symlink() f2fs: switch to fscrypt ->symlink() helper functions ext4: switch to fscrypt_get_symlink() ext4: switch to fscrypt ->symlink() helper functions fscrypt: new helper function - fscrypt_get_symlink() fscrypt: new helper functions for ->symlink() fscrypt: trim down fscrypt.h includes fscrypt: move fscrypt_is_dot_dotdot() to fs/crypto/fname.c fscrypt: move fscrypt_valid_enc_modes() to fscrypt_private.h ...
| * ext4: switch to fscrypt ->symlink() helper functionsEric Biggers2018-01-111-43/+15
| | | | | | | | | | Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | Merge tag 'ext4_for_linus' of ↵Linus Torvalds2018-02-031-3/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Only miscellaneous cleanups and bug fixes for ext4 this cycle" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: create ext4_kset dynamically ext4: create ext4_feat kobject dynamically ext4: release kobject/kset even when init/register fail ext4: fix incorrect indentation of if statement ext4: correct documentation for grpid mount option ext4: use 'sbi' instead of 'EXT4_SB(sb)' ext4: save error to disk in __ext4_grp_locked_error() jbd2: fix sphinx kernel-doc build warnings ext4: fix a race in the ext4 shutdown path mbcache: make sure c_entry_count is not decremented past zero ext4: no need flush workqueue before destroying it ext4: fixed alignment and minor code cleanup in ext4.h ext4: fix ENOSPC handling in DAX page fault handler dax: pass detailed error code from dax_iomap_fault() mbcache: revert "fs/mbcache.c: make count_objects() more robust" mbcache: initialize entry->e_referenced in mb_cache_entry_create() ext4: fix up remaining files with SPDX cleanups
| * | ext4: fix incorrect indentation of if statementColin Ian King2018-01-111-3/+3
| |/ | | | | | | | | | | | | | | | | | | | | | | The indentation is incorrect and spaces need replacing with a tab on the if statement. Cleans up smatch warning: fs/ext4/namei.c:3220 ext4_link() warn: inconsistent indenting Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* | Merge tag 'iversion-v4.16-1' of ↵Linus Torvalds2018-01-291-2/+3
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux Pull inode->i_version rework from Jeff Layton: "This pile of patches is a rework of the inode->i_version field. We have traditionally incremented that field on every inode data or metadata change. Typically this increment needs to be logged on disk even when nothing else has changed, which is rather expensive. It turns out though that none of the consumers of that field actually require this behavior. The only real requirement for all of them is that it be different iff the inode has changed since the last time the field was checked. Given that, we can optimize away most of the i_version increments and avoid dirtying inode metadata when the only change is to the i_version and no one is querying it. Queries of the i_version field are rather rare, so we can help write performance under many common workloads. This patch series converts existing accesses of the i_version field to a new API, and then converts all of the in-kernel filesystems to use it. The last patch in the series then converts the backend implementation to a scheme that optimizes away a large portion of the metadata updates when no one is looking at it. In my own testing this series significantly helps performance with small I/O sizes. I also got this email for Christmas this year from the kernel test robot (a 244% r/w bandwidth improvement with XFS over DAX, with 4k writes): https://lkml.org/lkml/2017/12/25/8 A few of the earlier patches in this pile are also flowing to you via other trees (mm, integrity, and nfsd trees in particular)". * tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: (22 commits) fs: handle inode->i_version more efficiently btrfs: only dirty the inode in btrfs_update_time if something was changed xfs: avoid setting XFS_ILOG_CORE if i_version doesn't need incrementing fs: only set S_VERSION when updating times if necessary IMA: switch IMA over to new i_version API xfs: convert to new i_version API ufs: use new i_version API ocfs2: convert to new i_version API nfsd: convert to new i_version API nfs: convert to new i_version API ext4: convert to new i_version API ext2: convert to new i_version API exofs: switch to new i_version API btrfs: convert to new i_version API afs: convert to new i_version API affs: convert to new i_version API fat: convert to new i_version API fs: don't take the i_lock in inode_inc_iversion fs: new API for handling inode->i_version ntfs: remove i_version handling ...
| * ext4: convert to new i_version APIJeff Layton2018-01-291-2/+2
| | | | | | | | Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Theodore Ts'o <tytso@mit.edu>
| * fs: new API for handling inode->i_versionJeff Layton2018-01-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a documentation blob that explains what the i_version field is, how it is expected to work, and how it is currently implemented by various filesystems. We already have inode_inc_iversion. Add several other functions for manipulating and accessing the i_version counter. For now, the implementation is trivial and basically works the way that all of the open-coded i_version accesses work today. Future patches will convert existing users of i_version to use the new API, and then convert the backend implementation to do things more efficiently. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz>
* | ext4: fix crash when a directory's i_size is too smallChandan Rajendra2017-12-111-0/+4
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On a ppc64 machine, when mounting a fuzzed ext2 image (generated by fsfuzzer) the following call trace is seen, VFS: brelse: Trying to free free buffer WARNING: CPU: 1 PID: 6913 at /root/repos/linux/fs/buffer.c:1165 .__brelse.part.6+0x24/0x40 .__brelse.part.6+0x20/0x40 (unreliable) .ext4_find_entry+0x384/0x4f0 .ext4_lookup+0x84/0x250 .lookup_slow+0xdc/0x230 .walk_component+0x268/0x400 .path_lookupat+0xec/0x2d0 .filename_lookup+0x9c/0x1d0 .vfs_statx+0x98/0x140 .SyS_newfstatat+0x48/0x80 system_call+0x58/0x6c This happens because the directory that ext4_find_entry() looks up has inode->i_size that is less than the block size of the filesystem. This causes 'nblocks' to have a value of zero. ext4_bread_batch() ends up not reading any of the directory file's blocks. This renders the entries in bh_use[] array to continue to have garbage data. buffer_uptodate() on bh_use[0] can then return a zero value upon which brelse() function is invoked. This commit fixes the bug by returning -ENOENT when the directory file has no associated blocks. Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Cc: stable@vger.kernel.org
* Merge tag 'fscrypt-for-linus' of ↵Linus Torvalds2017-11-141-45/+17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Lots of cleanups, mostly courtesy by Eric Biggers" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: fscrypt: lock mutex before checking for bounce page pool fscrypt: add a documentation file for filesystem-level encryption ext4: switch to fscrypt_prepare_setattr() ext4: switch to fscrypt_prepare_lookup() ext4: switch to fscrypt_prepare_rename() ext4: switch to fscrypt_prepare_link() ext4: switch to fscrypt_file_open() fscrypt: new helper function - fscrypt_prepare_setattr() fscrypt: new helper function - fscrypt_prepare_lookup() fscrypt: new helper function - fscrypt_prepare_rename() fscrypt: new helper function - fscrypt_prepare_link() fscrypt: new helper function - fscrypt_file_open() fscrypt: new helper function - fscrypt_require_key() fscrypt: remove unneeded empty fscrypt_operations structs fscrypt: remove ->is_encrypted() fscrypt: switch from ->is_encrypted() to IS_ENCRYPTED() fs, fscrypt: add an S_ENCRYPTED inode flag fscrypt: clean up include file mess
| * ext4: switch to fscrypt_prepare_lookup()Eric Biggers2017-10-181-16/+6
| | | | | | | | | | Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: switch to fscrypt_prepare_rename()Eric Biggers2017-10-181-26/+7
| | | | | | | | | | Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: switch to fscrypt_prepare_link()Eric Biggers2017-10-181-3/+4
| | | | | | | | | | Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ext4: make xattr inode reads fasterTahsin Erdogan2017-08-061-29/+14
| | | | | | | | | | | | | ext4_xattr_inode_read() currently reads each block sequentially while waiting for io operation to complete before moving on to the next block. This prevents request merging in block layer. Add a ext4_bread_batch() function that starts reads for all blocks then optionally waits for them to complete. A similar logic is used in ext4_find_entry(), so update that code to use the new function. Signed-off-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix dir_nlink behaviourAndreas Dilger2017-08-051-9/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The dir_nlink feature has been enabled by default for new ext4 filesystems since e2fsprogs-1.41 in 2008, and was automatically enabled by the kernel for older ext4 filesystems since the dir_nlink feature was added with ext4 in kernel 2.6.28+ when the subdirectory count exceeded EXT4_LINK_MAX-1. Automatically adding the file system features such as dir_nlink is generally frowned upon, since it could cause the file system to not be mountable on older kernel, thus preventing the administrator from rolling back to an older kernel if necessary. In this case, the administrator might also want to disable the feature because glibc's fts_read() function does not correctly optimize directory traversal for directories that use st_nlinks field of 1 to indicate that the number of links in the directory are not tracked by the file system, and could fail to traverse the full directory hierarchy. Fortunately, in the past ten years very few users have complained about incomplete file system traversal by glibc's fts_read(). This commit also changes ext4_inc_count() to allow i_nlinks to reach the full EXT4_LINK_MAX links on the parent directory (including "." and "..") before changing i_links_count to be 1. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196405 Signed-off-by: Andreas Dilger <adilger@dilger.ca> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: return EFSBADCRC if a bad checksum error is found in ext4_find_entry()Theodore Ts'o2017-06-231-1/+2
| | | | | | | Previously a bad directory block with a bad checksum is skipped; we should be returning EFSBADCRC (aka EBADMSG). Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: return EIO on read error in ext4_find_entryKhazhismel Kumykov2017-06-231-2/+2
| | | | | | | | Previously, a read error would be ignored and we would eventually return NULL from ext4_find_entry, which signals "no such file or directory". We should be returning EIO. Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
* ext4: add largedir featureArtem Blagodarenko2017-06-211-39/+85
| | | | | | | | | | | | | | | | | | This INCOMPAT_LARGEDIR feature allows larger directories to be created in ldiskfs, both with directory sizes over 2GB and and a maximum htree depth of 3 instead of the current limit of 2. These features are needed in order to exceed the current limit of approximately 10M entries in a single directory. This patch was originally written by Yang Sheng to support the Lustre server. [ Bumped the credits needed to update an indexed directory -- tytso ] Signed-off-by: Liang Zhen <liang.zhen@intel.com> Signed-off-by: Yang Sheng <yang.sheng@intel.com> Signed-off-by: Artem Blagodarenko <artem.blagodarenko@seagate.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
* ext4: remove unused d_name argument from ext4_search_dir() et al.Eric Biggers2017-05-241-8/+5
| | | | | | | | | Now that we are passing a struct ext4_filename, we do not need to pass around the original struct qstr too. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
* Merge tag 'fscrypt_for_linus' of ↵Linus Torvalds2017-05-081-81/+31
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Only bug fixes and cleanups for this merge window" * tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: fscrypt: correct collision claim for digested names MAINTAINERS: fscrypt: update mailing list, patchwork, and git ext4: clean up ext4_match() and callers f2fs: switch to using fscrypt_match_name() ext4: switch to using fscrypt_match_name() fscrypt: introduce helper function for filename matching fscrypt: avoid collisions when presenting long encrypted filenames f2fs: check entire encrypted bigname when finding a dentry ubifs: check for consistent encryption contexts in ubifs_lookup() f2fs: sync f2fs_lookup() with ext4_lookup() ext4: remove "nokey" check from ext4_lookup() fscrypt: fix context consistency check when key(s) unavailable fscrypt: Remove __packed from fscrypt_policy fscrypt: Move key structure and constants to uapi fscrypt: remove fscrypt_symlink_data_len() fscrypt: remove unnecessary checks for NULL operations
| * ext4: clean up ext4_match() and callersEric Biggers2017-05-041-56/+25
| | | | | | | | | | | | | | | | | | | | | | | | When ext4 encryption was originally merged, we were encrypting the user-specified filename in ext4_match(), introducing a lot of additional complexity into ext4_match() and its callers. This has since been changed to encrypt the filename earlier, so we can remove the gunk that's no longer needed. This more or less reverts ext4_search_dir() and ext4_find_dest_de() to the way they were in the v4.0 kernel. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: switch to using fscrypt_match_name()Eric Biggers2017-05-041-17/+5
| | | | | | | | | | | | | | | | Switch ext4 directory searches to use the fscrypt_match_name() helper function. There should be no functional change. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * fscrypt: avoid collisions when presenting long encrypted filenamesEric Biggers2017-05-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <gwendal@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: remove "nokey" check from ext4_lookup()Eric Biggers2017-05-041-8/+1
| | | | | | | | | | | | | | | | | | Now that fscrypt_has_permitted_context() correctly handles the case where we have the key for the parent directory but not the child, we don't need to try to work around this in ext4_lookup(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | ext4: trim return value and 'dir' argument from ext4_insert_dentry()Eric Biggers2017-04-291-11/+6
|/ | | | | | | | | | | In the initial implementation of ext4 encryption, the filename was encrypted in ext4_insert_dentry(), which could fail and also required access to the 'dir' inode. Since then ext4 filename encryption has been changed to encrypt the filename earlier, so we can revert the additions to ext4_insert_dentry(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: Add statx supportDavid Howells2017-04-031-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Return enhanced file attributes from the Ext4 filesystem. This includes the following: (1) The inode creation time (i_crtime) as stx_btime, setting STATX_BTIME. (2) Certain FS_xxx_FL flags are mapped to stx_attribute flags. This requires that all ext4 inodes have a getattr call, not just some of them, so to this end, split the ext4_getattr() function and only call part of it where appropriate. Example output: [root@andromeda ~]# touch foo [root@andromeda ~]# chattr +ai foo [root@andromeda ~]# /tmp/test-statx foo statx(foo) = 0 results=fff Size: 0 Blocks: 0 IO Block: 4096 regular file Device: 08:12 Inode: 2101950 Links: 1 Access: (0644/-rw-r--r--) Uid: 0 Gid: 0 Access: 2016-02-11 17:08:29.031795451+0000 Modify: 2016-02-11 17:08:29.031795451+0000 Change: 2016-02-11 17:11:11.987790114+0000 Birth: 2016-02-11 17:08:29.031795451+0000 Attributes: 0000000000000030 (-------- -------- -------- -------- -------- -------- -------- --ai----) Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ext4: add shutdown bit and check for itTheodore Ts'o2017-02-051-0/+12
| | | | | | | Add a shutdown bit that will cause ext4 processing to fail immediately with EIO. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix use-after-iput when fscrypt contexts are inconsistentEric Biggers2017-02-011-2/+4
| | | | | | | | | | | | | | In the case where the child's encryption context was inconsistent with its parent directory, we were using inode->i_sb and inode->i_ino after the inode had already been iput(). Fix this by doing the iput() in the correct places. Note: only ext4 had this bug, not f2fs and ubifs. Fixes: d9cdc9033181 ("ext4 crypto: enforce context consistency") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: don't allow encrypted operations without keysTheodore Ts'o2017-01-081-0/+12
| | | | | | | | | | | | | | While we allow deletes without the key, the following should not be permitted: # cd /vdc/encrypted-dir-without-key # ls -l total 4 -rw-r--r-- 1 root root 0 Dec 27 22:35 6,LKNRJsp209FbXoSvJWzB -rw-r--r-- 1 root root 286 Dec 27 22:35 uRJ5vJh9gE7vcomYMqTAyD # mv uRJ5vJh9gE7vcomYMqTAyD 6,LKNRJsp209FbXoSvJWzB Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* fscrypt: use ENOKEY when file cannot be created w/o keyEric Biggers2016-12-311-1/+3
| | | | | | | | | | | | | | | | | | | 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 <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: use current_time() for inode timestampsDeepa Dinamani2016-11-141-11/+13
| | | | | | | | | | | | | | | | | | | | CURRENT_TIME_SEC and CURRENT_TIME are not y2038 safe. current_time() will be transitioned to be y2038 safe along with vfs. current_time() returns timestamps according to the granularities set in the super_block. The granularity check in ext4_current_time() to call current_time() or CURRENT_TIME_SEC is not required. Use current_time() directly to obtain timestamps unconditionally, and remove ext4_current_time(). Quota files are assumed to be on the same filesystem. Hence, use current_time() for these files as well. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
* ext4: add missing KERN_CONT to a few more debugging usesJoe Perches2016-10-151-8/+10
| | | | | | | | | | | | | | | Recent commits require line continuing printks to always use pr_cont or KERN_CONT. Add these markings to a few more printks. Miscellaneaous: o Integrate the ea_idebug and ea_bdebug macros to use a single call to printk(KERN_DEBUG instead of 3 separate printks o Use the more common varargs macro style Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-10-101-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 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
| * fs: rename "rename2" i_op to "rename"Miklos Szeredi2016-09-271-1/+1
| | | | | | | | | | | | | | | | | | Generated patch: sed -i "s/\.rename2\t/\.rename\t\t/" `git grep -wl rename2` sed -i "s/\brename2\b/rename/g" `git grep -wl rename2` Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | Merge branch 'work.xattr' of ↵Linus Torvalds2016-10-101-6/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs xattr updates from Al Viro: "xattr stuff from Andreas This completes the switch to xattr_handler ->get()/->set() from ->getxattr/->setxattr/->removexattr" * 'work.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Remove {get,set,remove}xattr inode operations xattr: Stop calling {get,set,remove}xattr inode operations vfs: Check for the IOP_XATTR flag in listxattr xattr: Add __vfs_{get,set,remove}xattr helpers libfs: Use IOP_XATTR flag for empty directory handling vfs: Use IOP_XATTR flag for bad-inode handling vfs: Add IOP_XATTR inode operations flag vfs: Move xattr_resolve_name to the front of fs/xattr.c ecryptfs: Switch to generic xattr handlers sockfs: Get rid of getxattr iop sockfs: getxattr: Fail with -EOPNOTSUPP for invalid attribute names kernfs: Switch to generic xattr handlers hfs: Switch to generic xattr handlers jffs2: Remove jffs2_{get,set,remove}xattr macros xattr: Remove unnecessary NULL attribute name check
| * | vfs: Remove {get,set,remove}xattr inode operationsAndreas Gruenbacher2016-10-071-6/+0
| |/ | | | | | | | | | | | | These inode operations are no longer used; remove them. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | ext4: release bh in make_indexed_dirgmail2016-09-301-8/+6
| | | | | | | | | | | | | | | | | | | | | | The commit 6050d47adcad: "ext4: bail out from make_indexed_dir() on first error" could end up leaking bh2 in the error path. [ Also avoid renaming bh2 to bh, which just confuses things --tytso ] Cc: stable@vger.kernel.org Signed-off-by: yangsheng <yngsion@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | fscrypto: make filename crypto functions return 0 on successEric Biggers2016-09-151-4/+4
|/ | | | | | | | | | | | | | | | | | | | | | | Several filename crypto functions: fname_decrypt(), fscrypt_fname_disk_to_usr(), and fscrypt_fname_usr_to_disk(), returned the output length on success or -errno on failure. However, the output length was redundant with the value written to 'oname->len'. It is also potentially error-prone to make callers have to check for '< 0' instead of '!= 0'. Therefore, make these functions return 0 instead of a length, and make the callers who cared about the return value being a length use 'oname->len' instead. For consistency also make other callers check for a nonzero result rather than a negative result. This change also fixes the inconsistency of fname_encrypt() actually already returning 0 on success, not a length like the other filename crypto functions and as documented in its function comment. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
* Merge tag 'ext4_for_linus' of ↵Linus Torvalds2016-07-261-75/+69
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The major change this cycle is deleting ext4's copy of the file system encryption code and switching things over to using the copies in fs/crypto. I've updated the MAINTAINERS file to add an entry for fs/crypto listing Jaeguk Kim and myself as the maintainers. There are also a number of bug fixes, most notably for some problems found by American Fuzzy Lop (AFL) courtesy of Vegard Nossum. Also fixed is a writeback deadlock detected by generic/130, and some potential races in the metadata checksum code" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits) ext4: verify extent header depth ext4: short-cut orphan cleanup on error ext4: fix reference counting bug on block allocation error MAINTAINRES: fs-crypto maintainers update ext4 crypto: migrate into vfs's crypto engine ext2: fix filesystem deadlock while reading corrupted xattr block ext4: fix project quota accounting without quota limits enabled ext4: validate s_reserved_gdt_blocks on mount ext4: remove unused page_idx ext4: don't call ext4_should_journal_data() on the journal inode ext4: Fix WARN_ON_ONCE in ext4_commit_super() ext4: fix deadlock during page writeback ext4: correct error value of function verifying dx checksum ext4: avoid modifying checksum fields directly during checksum verification ext4: check for extents that wrap around jbd2: make journal y2038 safe jbd2: track more dependencies on transaction commit jbd2: move lockdep tracking to journal_s jbd2: move lockdep instrumentation for jbd2 handles ext4: respect the nobarrier mount option in nojournal mode ...
| * ext4 crypto: migrate into vfs's crypto engineJaegeuk Kim2016-07-101-68/+63
| | | | | | | | | | | | | | | | | | This patch removes the most parts of internal crypto codes. And then, it modifies and adds some ext4-specific crypt codes to use the generic facility. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: correct error value of function verifying dx checksumDaeho Jeong2016-07-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | ext4_dx_csum_verify() returns the success return value in two checksum verification failure cases. We need to set the return values to zero as failure like ext4_dirent_csum_verify() returning zero when failing to find a checksum dirent at the tail. Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
| * ext4: avoid modifying checksum fields directly during checksum verificationDaeho Jeong2016-07-031-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We temporally change checksum fields in buffers of some types of metadata into '0' for verifying the checksum values. By doing this without locking the buffer, some metadata's checksums, which are being committed or written back to the storage, could be damaged. In our test, several metadata blocks were found with damaged metadata checksum value during recovery process. When we only verify the checksum value, we have to avoid modifying checksum fields directly. Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com> Signed-off-by: Youngjin Gil <youngjin.gil@samsung.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
* | fs: have ll_rw_block users pass in op and flags separatelyMike Christie2016-06-071-1/+2
|/ | | | | | | | | | | This has ll_rw_block users pass in the operation and flags separately, so ll_rw_block can setup the bio op and bi_rw flags on the bio that is submitted. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* Merge tag 'ext4_for_linus' of ↵Linus Torvalds2016-05-241-2/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Fix a number of bugs, most notably a potential stale data exposure after a crash and a potential BUG_ON crash if a file has the data journalling flag enabled while it has dirty delayed allocation blocks that haven't been written yet. Also fix a potential crash in the new project quota code and a maliciously corrupted file system. In addition, fix some DAX-specific bugs, including when there is a transient ENOSPC situation and races between writes via direct I/O and an mmap'ed segment that could lead to lost I/O. Finally the usual set of miscellaneous cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits) ext4: pre-zero allocated blocks for DAX IO ext4: refactor direct IO code ext4: fix race in transient ENOSPC detection ext4: handle transient ENOSPC properly for DAX dax: call get_blocks() with create == 1 for write faults to unwritten extents ext4: remove unmeetable inconsisteny check from ext4_find_extent() jbd2: remove excess descriptions for handle_s ext4: remove unnecessary bio get/put ext4: silence UBSAN in ext4_mb_init() ext4: address UBSAN warning in mb_find_order_for_block() ext4: fix oops on corrupted filesystem ext4: fix check of dqget() return value in ext4_ioctl_setproject() ext4: clean up error handling when orphan list is corrupted ext4: fix hang when processing corrupted orphaned inode list ext4: remove trailing \n from ext4_warning/ext4_error calls ext4: fix races between changing inode journal mode and ext4_writepages ext4: handle unwritten or delalloc buffers before enabling data journaling ext4: fix jbd2 handle extension in ext4_ext_truncate_extend_restart() ext4: do not ask jbd2 to write data for delalloc buffers jbd2: add support for avoiding data writes during transaction commits ...
| * ext4: fix oops on corrupted filesystemJan Kara2016-05-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When filesystem is corrupted in the right way, it can happen ext4_mark_iloc_dirty() in ext4_orphan_add() returns error and we subsequently remove inode from the in-memory orphan list. However this deletion is done with list_del(&EXT4_I(inode)->i_orphan) and thus we leave i_orphan list_head with a stale content. Later we can look at this content causing list corruption, oops, or other issues. The reported trace looked like: WARNING: CPU: 0 PID: 46 at lib/list_debug.c:53 __list_del_entry+0x6b/0x100() list_del corruption, 0000000061c1d6e0->next is LIST_POISON1 0000000000100100) CPU: 0 PID: 46 Comm: ext4.exe Not tainted 4.1.0-rc4+ #250 Stack: 60462947 62219960 602ede24 62219960 602ede24 603ca293 622198f0 602f02eb 62219950 6002c12c 62219900 601b4d6b Call Trace: [<6005769c>] ? vprintk_emit+0x2dc/0x5c0 [<602ede24>] ? printk+0x0/0x94 [<600190bc>] show_stack+0xdc/0x1a0 [<602ede24>] ? printk+0x0/0x94 [<602ede24>] ? printk+0x0/0x94 [<602f02eb>] dump_stack+0x2a/0x2c [<6002c12c>] warn_slowpath_common+0x9c/0xf0 [<601b4d6b>] ? __list_del_entry+0x6b/0x100 [<6002c254>] warn_slowpath_fmt+0x94/0xa0 [<602f4d09>] ? __mutex_lock_slowpath+0x239/0x3a0 [<6002c1c0>] ? warn_slowpath_fmt+0x0/0xa0 [<60023ebf>] ? set_signals+0x3f/0x50 [<600a205a>] ? kmem_cache_free+0x10a/0x180 [<602f4e88>] ? mutex_lock+0x18/0x30 [<601b4d6b>] __list_del_entry+0x6b/0x100 [<601177ec>] ext4_orphan_del+0x22c/0x2f0 [<6012f27c>] ? __ext4_journal_start_sb+0x2c/0xa0 [<6010b973>] ? ext4_truncate+0x383/0x390 [<6010bc8b>] ext4_write_begin+0x30b/0x4b0 [<6001bb50>] ? copy_from_user+0x0/0xb0 [<601aa840>] ? iov_iter_fault_in_readable+0xa0/0xc0 [<60072c4f>] generic_perform_write+0xaf/0x1e0 [<600c4166>] ? file_update_time+0x46/0x110 [<60072f0f>] __generic_file_write_iter+0x18f/0x1b0 [<6010030f>] ext4_file_write_iter+0x15f/0x470 [<60094e10>] ? unlink_file_vma+0x0/0x70 [<6009b180>] ? unlink_anon_vmas+0x0/0x260 [<6008f169>] ? free_pgtables+0xb9/0x100 [<600a6030>] __vfs_write+0xb0/0x130 [<600a61d5>] vfs_write+0xa5/0x170 [<600a63d6>] SyS_write+0x56/0xe0 [<6029fcb0>] ? __libc_waitpid+0x0/0xa0 [<6001b698>] handle_syscall+0x68/0x90 [<6002633d>] userspace+0x4fd/0x600 [<6002274f>] ? save_registers+0x1f/0x40 [<60028bd7>] ? arch_prctl+0x177/0x1b0 [<60017bd5>] fork_handler+0x85/0x90 Fix the problem by using list_del_init() as we always should with i_orphan list. CC: stable@vger.kernel.org Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * ext4: remove trailing \n from ext4_warning/ext4_error callsJakub Wilk2016-04-271-1/+1
| | | | | | | | | | | | | | Messages passed to ext4_warning() or ext4_error() don't need trailing newlines, because these function add the newlines themselves. Signed-off-by: Jakub Wilk <jwilk@jwilk.net>
| * ext4: allow readdir()'s of large empty directories to be interruptedTheodore Ts'o2016-04-231-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a directory has a large number of empty blocks, iterating over all of them can take a long time, leading to scheduler warnings and users getting irritated when they can't kill a process in the middle of one of these long-running readdir operations. Fix this by adding checks to ext4_readdir() and ext4_htree_fill_tree(). This was reverted earlier due to a typo in the original commit where I experimented with using signal_pending() instead of fatal_signal_pending(). The test was in the wrong place if we were going to return signal_pending() since we would end up returning duplicant entries. See 9f2394c9be47 for a more detailed explanation. Added fix as suggested by Linus to check for signal_pending() in in the filldir() functions. Reported-by: Benjamin LaHaise <bcrl@kvack.org> Google-Bug-Id: 27880676 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * Revert "ext4: allow readdir()'s of large empty directories to be interrupted"Linus Torvalds2016-04-101-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 1028b55bafb7611dda1d8fed2aeca16a436b7dff. It's broken: it makes ext4 return an error at an invalid point, causing the readdir wrappers to write the the position of the last successful directory entry into the position field, which means that the next readdir will now return that last successful entry _again_. You can only return fatal errors (that terminate the readdir directory walk) from within the filesystem readdir functions, the "normal" errors (that happen when the readdir buffer fills up, for example) happen in the iterorator where we know the position of the actual failing entry. I do have a very different patch that does the "signal_pending()" handling inside the iterator function where it is allowable, but while that one passes all the sanity checks, I screwed up something like four times while emailing it out, so I'm not going to commit it today. So my track record is not good enough, and the stars will have to align better before that one gets committed. And it would be good to get some review too, of course, since celestial alignments are always an iffy debugging model. IOW, let's just revert the commit that caused the problem for now. Reported-by: Greg Thelen <gthelen@google.com> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * ext4: allow readdir()'s of large empty directories to be interruptedTheodore Ts'o2016-03-301-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | If a directory has a large number of empty blocks, iterating over all of them can take a long time, leading to scheduler warnings and users getting irritated when they can't kill a process in the middle of one of these long-running readdir operations. Fix this by adding checks to ext4_readdir() and ext4_htree_fill_tree(). Reported-by: Benjamin LaHaise <bcrl@kvack.org> Google-Bug-Id: 27880676 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | don't bother with ->d_inode->i_sb - it's always equal to ->d_sbAl Viro2016-04-101-2/+2
|/ | | | | | ... and neither can ever be NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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