kernel/include/linux/fsnotify_backend.h, branch linux-4.15.y

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2017-11-14T22:13:11Z

Pull quota, ext2, isofs and udf fixes from Jan Kara: - two small quota error handling fixes - two isofs fixes for architectures with signed char - several udf block number overflow and signedness fixes - ext2 rework of mount option handling to avoid GFP_KERNEL allocation with spinlock held - ... it also contains a patch to implement auditing of responses to fanotify permission events. That should have been in the fanotify pull request but I mistakenly merged that patch into a wrong branch and noticed only now at which point I don't think it's worth rebasing and redoing. * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: quota: be aware of error from dquot_initialize quota: fix potential infinite loop isofs: use unsigned char types consistently isofs: fix timestamps beyond 2027 udf: Fix some sign-conversion warnings udf: Fix signed/unsigned format specifiers udf: Fix 64-bit sign extension issues affecting blocks > 0x7FFFFFFF udf: Remove some outdate references from documentation udf: Avoid overflow when session starts at large offset ext2: Fix possible sleep in atomic during mount option parsing ext2: Parse mount options into a dedicated structure audit: Record fanotify access control decisions

Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2017-11-14T22:08:20Z

Pull fsnotify updates from Jan Kara: - fixes of use-after-tree issues when handling fanotify permission events from Miklos - refcount_t conversions from Elena - fixes of ENOMEM handling in dnotify and fsnotify from me * 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fsnotify: convert fsnotify_mark.refcnt from atomic_t to refcount_t fanotify: clean up CONFIG_FANOTIFY_ACCESS_PERMISSIONS ifdefs fsnotify: clean up fsnotify() fanotify: fix fsnotify_prepare_user_wait() failure fsnotify: fix pinning group in fsnotify_prepare_user_wait() fsnotify: pin both inode and vfsmount mark fsnotify: clean up fsnotify_prepare/finish_user_wait() fsnotify: convert fsnotify_group.refcnt from atomic_t to refcount_t fsnotify: Protect bail out path of fsnotify_add_mark_locked() properly dnotify: Handle errors from fsnotify_add_mark_locked() in fcntl_dirnotify()

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

fsnotify: convert fsnotify_mark.refcnt from atomic_t to refcount_t

2017-10-31T16:54:56Z

atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable fsnotify_mark.refcnt is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook Reviewed-by: David Windsor Reviewed-by: Hans Liljestrand Signed-off-by: Elena Reshetova Signed-off-by: Jan Kara

fanotify: clean up CONFIG_FANOTIFY_ACCESS_PERMISSIONS ifdefs

2017-10-31T16:54:56Z

The only negative from this patch should be an addition of 32bytes to 'struct fsnotify_group' if CONFIG_FANOTIFY_ACCESS_PERMISSIONS is not defined. Reviewed-by: Amir Goldstein Signed-off-by: Miklos Szeredi Signed-off-by: Jan Kara

fsnotify: convert fsnotify_group.refcnt from atomic_t to refcount_t

2017-10-31T16:54:56Z

atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable fsnotify_group.refcnt is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook Reviewed-by: David Windsor Reviewed-by: Hans Liljestrand Signed-off-by: Elena Reshetova Signed-off-by: Jan Kara

audit: Record fanotify access control decisions

2017-10-10T11:18:06Z

The fanotify interface allows user space daemons to make access control decisions. Under common criteria requirements, we need to optionally record decisions based on policy. This patch adds a bit mask, FAN_AUDIT, that a user space daemon can 'or' into the response decision which will tell the kernel that it made a decision and record it. It would be used something like this in user space code: response.response = FAN_DENY | FAN_AUDIT; write(fd, &response, sizeof(struct fanotify_response)); When the syscall ends, the audit system will record the decision as a AUDIT_FANOTIFY auxiliary record to denote that the reason this event occurred is the result of an access control decision from fanotify rather than DAC or MAC policy. A sample event looks like this: type=PATH msg=audit(1504310584.332:290): item=0 name="./evil-ls" inode=1319561 dev=fc:03 mode=0100755 ouid=1000 ogid=1000 rdev=00:00 obj=unconfined_u:object_r:user_home_t:s0 nametype=NORMAL type=CWD msg=audit(1504310584.332:290): cwd="/home/sgrubb" type=SYSCALL msg=audit(1504310584.332:290): arch=c000003e syscall=2 success=no exit=-1 a0=32cb3fca90 a1=0 a2=43 a3=8 items=1 ppid=901 pid=959 auid=1000 uid=1000 gid=1000 euid=1000 suid=1000 fsuid=1000 egid=1000 sgid=1000 fsgid=1000 tty=pts1 ses=3 comm="bash" exe="/usr/bin/bash" subj=unconfined_u:unconfined_r:unconfined_t: s0-s0:c0.c1023 key=(null) type=FANOTIFY msg=audit(1504310584.332:290): resp=2 Prior to using the audit flag, the developer needs to call fanotify_init or'ing in FAN_ENABLE_AUDIT to ensure that the kernel supports auditing. The calling process must also have the CAP_AUDIT_WRITE capability. Signed-off-by: sgrubb Reviewed-by: Amir Goldstein Signed-off-by: Jan Kara

fsnotify: Move ->free_mark callback to fsnotify_ops

2017-04-10T15:37:36Z

Pointer to ->free_mark callback unnecessarily occupies one long in each fsnotify_mark although they are the same for all marks from one notification group. Move the callback pointer to fsnotify_ops. Reviewed-by: Miklos Szeredi Reviewed-by: Amir Goldstein Signed-off-by: Jan Kara

fsnotify: Add group pointer in fsnotify_init_mark()

2017-04-10T15:37:36Z

Currently we initialize mark->group only in fsnotify_add_mark_lock(). However we will need to access fsnotify_ops of corresponding group from fsnotify_put_mark() so we need mark->group initialized earlier. Do that in fsnotify_init_mark() which has a consequence that once fsnotify_init_mark() is called on a mark, the mark has to be destroyed by fsnotify_put_mark(). Reviewed-by: Miklos Szeredi Reviewed-by: Amir Goldstein Signed-off-by: Jan Kara

fsnotify: Remove fsnotify_find_{inode|vfsmount}_mark()

2017-04-10T15:37:36Z

These are very thin wrappers, just remove them. Drop fs/notify/vfsmount_mark.c as it is empty now. Reviewed-by: Miklos Szeredi Reviewed-by: Amir Goldstein Signed-off-by: Jan Kara