user/sven/linux.git/include/linux/namei.h, branch v5.4.276

new helper: lookup_positive_unlocked()

2023-09-23T08:59:40Z

[ Upstream commit 6c2d4798a8d16cf4f3a28c3cd4af4f1dcbbb4d04 ] Most of the callers of lookup_one_len_unlocked() treat negatives are ERR_PTR(-ENOENT). Provide a helper that would do just that. Note that a pinned positive dentry remains positive - it's ->d_inode is stable, etc.; a pinned _negative_ dentry can become positive at any point as long as you are not holding its parent at least shared. So using lookup_one_len_unlocked() needs to be careful; lookup_positive_unlocked() is safer and that's what the callers end up open-coding anyway. Signed-off-by: Al Viro Stable-dep-of: 0d5a4f8f775f ("fs: Fix error checking for d_hash_and_lookup()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

fs/namei.c: keep track of nd->root refcount status

2019-09-03T13:30:45Z

The rules for nd->root are messy: * if we have LOOKUP_ROOT, it doesn't contribute to refcounts * if we have LOOKUP_RCU, it doesn't contribute to refcounts * if nd->root.mnt is NULL, it doesn't contribute to refcounts * otherwise it does contribute terminate_walk() needs to drop the references if they are contributing. So everything else should be careful not to confuse it, leading to rather convoluted code. It's easier to keep track of whether we'd grabbed the reference(s) explicitly. Use a new flag for that. Don't bother with zeroing nd->root.mnt on unlazy failures and in terminate_walk - it's not needed anymore (terminate_walk() won't care and the next path_init() will zero nd->root in !LOOKUP_ROOT case anyway). Resulting rules for nd->root refcounts are much simpler: they are contributing iff LOOKUP_ROOT_GRABBED is set in nd->flags. Signed-off-by: Al Viro

kill the last users of user_{path,lpath,path_dir}()

2019-08-31T01:30:13Z

old wrappers with few callers remaining; put them out of their misery... Signed-off-by: Al Viro

namei.h: get the comments on LOOKUP_... in sync with reality

2019-08-31T01:30:12Z

Signed-off-by: Al Viro

kill LOOKUP_NO_EVAL, don't bother including namei.h from audit.h

2019-08-31T01:29:32Z

The former has no users left; the latter was only to get LOOKUP_... values to remapper in audit_inode() and that's an ex-parrot now. All places that use symbols from namei.h include it either directly or (in a few cases) via a local header, like fs/autofs/autofs_i.h Signed-off-by: Al Viro

audit: ignore fcaps on umount

2019-01-31T01:51:47Z

Don't fetch fcaps when umount2 is called to avoid a process hang while it waits for the missing resource to (possibly never) re-appear. Note the comment above user_path_mountpoint_at(): * A umount is a special case for path walking. We're not actually interested * in the inode in this situation, and ESTALE errors can be a problem. We * simply want track down the dentry and vfsmount attached at the mountpoint * and avoid revalidating the last component. This can happen on ceph, cifs, 9p, lustre, fuse (gluster) or NFS. Please see the github issue tracker https://github.com/linux-audit/audit-kernel/issues/100 Signed-off-by: Richard Guy Briggs [PM: merge fuzz in audit_log_fcaps()] Signed-off-by: Paul Moore

afs: Display manually added cells in dynamic root mount

2018-06-15T14:27:09Z

Alter the dynroot mount so that cells created by manipulation of /proc/fs/afs/cells and /proc/fs/afs/rootcell and by specification of a root cell as a module parameter will cause directories for those cells to be created in the dynamic root superblock for the network namespace[*]. To this end: (1) Only one dynamic root superblock is now created per network namespace and this is shared between all attempts to mount it. This makes it easier to find the superblock to modify. (2) When a dynamic root superblock is created, the list of cells is walked and directories created for each cell already defined. (3) When a new cell is added, if a dynamic root superblock exists, a directory is created for it. (4) When a cell is destroyed, the directory is removed. (5) These directories are created by calling lookup_one_len() on the root dir which automatically creates them if they don't exist. [*] Inasmuch as network namespaces are currently supported here. Signed-off-by: David Howells

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

make sure that mntns_install() doesn't end up with referral for root

2017-04-21T18:05:36Z

new flag: LOOKUP_DOWN. If the starting point is overmounted, cross into whatever's mounted on top, triggering referrals et.al. Use that instead of follow_down_one() loop in mntns_install(), handle errors properly. Signed-off-by: Al Viro

Revert "vfs: add lookup_hash() helper"

2016-07-29T19:17:52Z

This reverts commit 3c9fe8cdff1b889a059a30d22f130372f2b3885f. As Miklos points out in commit c1b2cc1a765a, the "lookup_hash()" helper is now unused, and in fact, with the hash salting changes, since the hash of a dentry name now depends on the directory dentry it is in, the helper function isn't even really likely to be useful. So rather than keep it around in case somebody else might end up finding a use for it, let's just remove the helper and not trick people into thinking it might be a useful thing. For example, I had obviously completely missed how the helper didn't follow the normal dentry hashing patterns, and how the hash salting patch broke overlayfs. Things would quietly build and look sane, but not work. Suggested-by: Miklos Szeredi Signed-off-by: Linus Torvalds