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2019-07-18proc/sysctl: add shared variables for range checkMatteo Croce
In the sysctl code the proc_dointvec_minmax() function is often used to validate the user supplied value between an allowed range. This function uses the extra1 and extra2 members from struct ctl_table as minimum and maximum allowed value. On sysctl handler declaration, in every source file there are some readonly variables containing just an integer which address is assigned to the extra1 and extra2 members, so the sysctl range is enforced. The special values 0, 1 and INT_MAX are very often used as range boundary, leading duplication of variables like zero=0, one=1, int_max=INT_MAX in different source files: $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l 248 Add a const int array containing the most commonly used values, some macros to refer more easily to the correct array member, and use them instead of creating a local one for every object file. This is the bloat-o-meter output comparing the old and new binary compiled with the default Fedora config: # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164) Data old new delta sysctl_vals - 12 +12 __kstrtab_sysctl_vals - 12 +12 max 14 10 -4 int_max 16 - -16 one 68 - -68 zero 128 28 -100 Total: Before=20583249, After=20583085, chg -0.00% [mcroce@redhat.com: tipc: remove two unused variables] Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com [akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c] [arnd@arndb.de: proc/sysctl: make firmware loader table conditional] Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de [akpm@linux-foundation.org: fix fs/eventpoll.c] Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-12memcg, fsnotify: no oom-kill for remote memcg chargingShakeel Butt
Commit d46eb14b735b ("fs: fsnotify: account fsnotify metadata to kmemcg") added remote memcg charging for fanotify and inotify event objects. The aim was to charge the memory to the listener who is interested in the events but without triggering the OOM killer. Otherwise there would be security concerns for the listener. At the time, oom-kill trigger was not in the charging path. A parallel work added the oom-kill back to charging path i.e. commit 29ef680ae7c2 ("memcg, oom: move out_of_memory back to the charge path"). So to not trigger oom-killer in the remote memcg, explicitly add __GFP_RETRY_MAYFAIL to the fanotigy and inotify event allocations. Link: http://lkml.kernel.org/r/20190514212259.156585-2-shakeelb@google.com Signed-off-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Roman Gushchin <guro@fb.com> Acked-by: Jan Kara <jack@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-10Merge tag 'fsnotify_for_v5.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: "This contains cleanups of the fsnotify name removal hook and also a patch to disable fanotify permission events for 'proc' filesystem" * tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fsnotify: get rid of fsnotify_nameremove() fsnotify: move fsnotify_nameremove() hook out of d_delete() configfs: call fsnotify_rmdir() hook debugfs: call fsnotify_{unlink,rmdir}() hooks debugfs: simplify __debugfs_remove_file() devpts: call fsnotify_unlink() hook tracefs: call fsnotify_{unlink,rmdir}() hooks rpc_pipefs: call fsnotify_{unlink,rmdir}() hooks btrfs: call fsnotify_rmdir() hook fsnotify: add empty fsnotify_{unlink,rmdir}() hooks fanotify: Disallow permission events for proc filesystem
2019-06-20fsnotify: get rid of fsnotify_nameremove()Amir Goldstein
For all callers of fsnotify_{unlink,rmdir}(), we made sure that d_parent and d_name are stable. Therefore, fsnotify_{unlink,rmdir}() do not need the safety measures in fsnotify_nameremove() to stabilize parent and name. We can now simplify those hooks and get rid of fsnotify_nameremove(). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-19fanotify: update connector fsid cache on add markAmir Goldstein
When implementing connector fsid cache, we only initialized the cache when the first mark added to object was added by FAN_REPORT_FID group. We forgot to update conn->fsid when the second mark is added by FAN_REPORT_FID group to an already attached connector without fsid cache. Reported-and-tested-by: syzbot+c277e8e2f46414645508@syzkaller.appspotmail.com Fixes: 77115225acc6 ("fanotify: cache fsid in fsnotify_mark_connector") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-28fanotify: Disallow permission events for proc filesystemJan Kara
Proc filesystem has special locking rules for various files. Thus fanotify which opens files on event delivery can easily deadlock against another process that waits for fanotify permission event to be handled. Since permission events on /proc have doubtful value anyway, just disallow them. Link: https://lore.kernel.org/linux-fsdevel/20190320131642.GE9485@quack2.suse.cz/ Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 44 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091651.032047323@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 18Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program see the file copying if not write to the free software foundation 675 mass ave cambridge ma 02139 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 52 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154042.342335923@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-13Merge tag 'fsnotify_for_v5.2-rc1' of ↵Linus Torvalds
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify fixes from Jan Kara: "Two fsnotify fixes" * tag 'fsnotify_for_v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fsnotify: fix unlink performance regression fsnotify: Clarify connector assignment in fsnotify_add_mark_list()
2019-05-09fsnotify: fix unlink performance regressionAmir Goldstein
__fsnotify_parent() has an optimization in place to avoid unneeded take_dentry_name_snapshot(). When fsnotify_nameremove() was changed not to call __fsnotify_parent(), we left out the optimization. Kernel test robot reported a 5% performance regression in concurrent unlink() workload. Reported-by: kernel test robot <rong.a.chen@intel.com> Link: https://lore.kernel.org/lkml/20190505062153.GG29809@shao2-debian/ Link: https://lore.kernel.org/linux-fsdevel/20190104090357.GD22409@quack2.suse.cz/ Fixes: 5f02a8776384 ("fsnotify: annotate directory entry modification events") CC: stable@vger.kernel.org Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-07Merge branch 'work.dcache' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc dcache updates from Al Viro: "Most of this pile is putting name length into struct name_snapshot and making use of it. The beginning of this series ("ovl_lookup_real_one(): don't bother with strlen()") ought to have been split in two (separate switch of name_snapshot to struct qstr from overlayfs reaping the trivial benefits of that), but I wanted to avoid a rebase - by the time I'd spotted that it was (a) in -next and (b) close to 5.1-final ;-/" * 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: audit_compare_dname_path(): switch to const struct qstr * audit_update_watch(): switch to const struct qstr * inotify_handle_event(): don't bother with strlen() fsnotify: switch send_to_group() and ->handle_event to const struct qstr * fsnotify(): switch to passing const struct qstr * for file_name switch fsnotify_move() to passing const struct qstr * for old_name ovl_lookup_real_one(): don't bother with strlen() sysv: bury the broken "quietly truncate the long filenames" logics nsfs: unobfuscate unexport d_alloc_pseudo()
2019-05-07Merge tag 'pidfd-v5.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull pidfd updates from Christian Brauner: "This patchset makes it possible to retrieve pidfds at process creation time by introducing the new flag CLONE_PIDFD to the clone() system call. Linus originally suggested to implement this as a new flag to clone() instead of making it a separate system call. After a thorough review from Oleg CLONE_PIDFD returns pidfds in the parent_tidptr argument. This means we can give back the associated pid and the pidfd at the same time. Access to process metadata information thus becomes rather trivial. As has been agreed, CLONE_PIDFD creates file descriptors based on anonymous inodes similar to the new mount api. They are made unconditional by this patchset as they are now needed by core kernel code (vfs, pidfd) even more than they already were before (timerfd, signalfd, io_uring, epoll etc.). The core patchset is rather small. The bulky looking changelist is caused by David's very simple changes to Kconfig to make anon inodes unconditional. A pidfd comes with additional information in fdinfo if the kernel supports procfs. The fdinfo file contains the pid of the process in the callers pid namespace in the same format as the procfs status file, i.e. "Pid:\t%d". To remove worries about missing metadata access this patchset comes with a sample/test program that illustrates how a combination of CLONE_PIDFD and pidfd_send_signal() can be used to gain race-free access to process metadata through /proc/<pid>. Further work based on this patchset has been done by Joel. His work makes pidfds pollable. It finished too late for this merge window. I would prefer to have it sitting in linux-next for a while and send it for inclusion during the 5.3 merge window" * tag 'pidfd-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: samples: show race-free pidfd metadata access signal: support CLONE_PIDFD with pidfd_send_signal clone: add CLONE_PIDFD Make anon_inodes unconditional
2019-05-01fsnotify: Clarify connector assignment in fsnotify_add_mark_list()Jan Kara
Add a comment explaining why WRITE_ONCE() is enough when setting mark->connector which can get dereferenced by RCU protected readers. Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-28fsnotify: Fix NULL ptr deref in fanotify_get_fsid()Jan Kara
fanotify_get_fsid() is reading mark->connector->fsid under srcu. It can happen that it sees mark not fully initialized or mark that is already detached from the object list. In these cases mark->connector can be NULL leading to NULL ptr dereference. Fix the problem by being careful when reading mark->connector and check it for being NULL. Also use WRITE_ONCE when writing the mark just to prevent compiler from doing something stupid. Reported-by: syzbot+15927486a4f1bfcbaf91@syzkaller.appspotmail.com Fixes: 77115225acc6 ("fanotify: cache fsid in fsnotify_mark_connector") Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-26inotify_handle_event(): don't bother with strlen()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26fsnotify: switch send_to_group() and ->handle_event to const struct qstr *Al Viro
note that conditions surrounding accesses to dname in audit_watch_handle_event() and audit_mark_handle_event() guarantee that dname won't have been NULL. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26fsnotify(): switch to passing const struct qstr * for file_nameAl Viro
Note that in fnsotify_move() and fsnotify_link() we are guaranteed that dentry->d_name won't change during the fsnotify() evaluation (by having the parent directory locked exclusive), so we don't need to fetch dentry->d_name.name in the callers. In fsnotify_dirent() the same stability of dentry->d_name is also true, but it's a bit more convoluted - there is one callchain (devpts_pty_new() -> fsnotify_create() -> fsnotify_dirent()) where the parent is _not_ locked, but on devpts ->d_name of everything is unchanging; it has neither explicit nor implicit renames. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26ovl_lookup_real_one(): don't bother with strlen()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-19Make anon_inodes unconditionalDavid Howells
Make the anon_inodes facility unconditional so that it can be used by core VFS code and pidfd code. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [christian@brauner.io: adapt commit message to mention pidfds] Signed-off-by: Christian Brauner <christian@brauner.io>
2019-03-19fanotify: Allow copying of file handle to userspaceJan Kara
When file handle is embedded inside fanotify_event and usercopy checks are enabled, we get a warning like: Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLAB object 'fanotify_event' (offset 40, size 8)! WARNING: CPU: 1 PID: 7649 at mm/usercopy.c:78 usercopy_warn+0xeb/0x110 mm/usercopy.c:78 Annotate handling in fanotify_event properly to mark copying it to userspace is fine. Reported-by: syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com Fixes: a8b13aa20afb ("fanotify: enable FAN_REPORT_FID init flag") Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-11inotify: Fix fsnotify_mark refcount leak in inotify_update_existing_watch()ZhangXiaoxu
Commit 4d97f7d53da7dc83 ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()") forgot to call fsnotify_put_mark() with IN_MASK_CREATE after fsnotify_find_mark() Fixes: 4d97f7d53da7dc83 ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()") Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-21fanotify: Make waits for fanotify events only killableJan Kara
Making waits for response to fanotify permission events interruptible can result in EINTR returns from open(2) or other syscalls when there's e.g. AV software that's monitoring the file. Orion reports that e.g. bash is complaining like: bash: /etc/bash_completion.d/itweb-settings.bash: Interrupted system call So for now convert the wait from interruptible to only killable one. That is mostly invisible to userspace. Sadly this breaks hibernation with fanotify permission events pending again but we have to put more thought into how to fix this without regressing userspace visible behavior. Reported-by: Orion Poplawski <orion@nwra.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18fanotify: Use interruptible wait when waiting for permission eventsJan Kara
When waiting for response to fanotify permission events, we currently use uninterruptible waits. That makes code simple however it can cause lots of processes to end up in uninterruptible sleep with hard reboot being the only alternative in case fanotify listener process stops responding (e.g. due to a bug in its implementation). Uninterruptible sleep also makes system hibernation fail if the listener gets frozen before the process generating fanotify permission event. Fix these problems by using interruptible sleep for waiting for response to fanotify event. This is slightly tricky though - we have to detect when the event got already reported to userspace as in that case we must not free the event. Instead we push the responsibility for freeing the event to the process that will write response to the event. Reported-by: Orion Poplawski <orion@nwra.com> Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18fanotify: Track permission event stateJan Kara
Track whether permission event got already reported to userspace and whether userspace already answered to the permission event. Protect stores to this field together with updates to ->response field by group->notification_lock. This will allow aborting wait for reply to permission event from userspace. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18fanotify: Simplify cleaning of access_listJan Kara
Simplify iteration cleaning access_list in fanotify_release(). That will make following changes more obvious. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18fsnotify: Create function to remove event from notification listJan Kara
Create function to remove event from the notification list. Later it will be used from more places. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18fanotify: Move locking inside get_one_event()Jan Kara
get_one_event() has a single caller and that just locks notification_lock around the call. Move locking inside get_one_event() as that will make using ->response field for permission event state easier. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18fanotify: Fold dequeue_event() into process_access_response()Jan Kara
Fold dequeue_event() into process_access_response(). This will make changes to use of ->response field easier. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-14fanotify: Select EXPORTFSJan Kara
Fanotify now uses exportfs_encode_inode_fh() so it needs to select EXPORTFS. Fixes: e9e0c8903009 "fanotify: encode file identifier for FAN_REPORT_FID" Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: report FAN_ONDIR to listener with FAN_REPORT_FIDAmir Goldstein
dirent modification events (create/delete/move) do not carry the child entry name/inode information. Instead, we report FAN_ONDIR for mkdir/rmdir so user can differentiate them from creat/unlink. This is consistent with inotify reporting IN_ISDIR with dirent events and is useful for implementing recursive directory tree watcher. We avoid merging dirent events referring to subdirs with dirent events referring to non subdirs, otherwise, user won't be able to tell from a mask FAN_CREATE|FAN_DELETE|FAN_ONDIR if it describes mkdir+unlink pair or rmdir+create pair of events. For backward compatibility and consistency, do not report FAN_ONDIR to user in legacy fanotify mode (reporting fd) and report FAN_ONDIR to user in FAN_REPORT_FID mode for all event types. Cc: <linux-api@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: add support for create/attrib/move/delete eventsAmir Goldstein
Add support for events with data type FSNOTIFY_EVENT_INODE (e.g. create/attrib/move/delete) for inode and filesystem mark types. The "inode" events do not carry enough information (i.e. path) to report event->fd, so we do not allow setting a mask for those events unless group supports reporting fid. The "inode" events are not supported on a mount mark, because they do not carry enough information (i.e. path) to be filtered by mount point. The "dirent" events (create/move/delete) report the fid of the parent directory where events took place without specifying the filename of the child. In the future, fanotify may get support for reporting filename information for those events. Cc: <linux-api@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: support events with data type FSNOTIFY_EVENT_INODEAmir Goldstein
When event data type is FSNOTIFY_EVENT_INODE, we don't have a refernece to the mount, so we will not be able to open a file descriptor when user reads the event. However, if the listener has enabled reporting file identifier with the FAN_REPORT_FID init flag, we allow reporting those events and we use an identifier inode to encode fid. The inode to use as identifier when reporting fid depends on the event. For dirent modification events, we report the modified directory inode and we report the "victim" inode otherwise. For example: FS_ATTRIB reports the child inode even if reported on a watched parent. FS_CREATE reports the modified dir inode and not the created inode. [JK: Fixup condition in fanotify_group_event_mask()] Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: check FS_ISDIR flag instead of d_is_dir()Amir Goldstein
All fsnotify hooks set the FS_ISDIR flag for events that happen on directory victim inodes except for fsnotify_perm(). Add the missing FS_ISDIR flag in fsnotify_perm() hook and let fanotify_group_event_mask() check the FS_ISDIR flag instead of checking if path argument is a directory. This is needed for fanotify support for event types that do not carry path information. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fsnotify: report FS_ISDIR flag with MOVE_SELF and DELETE_SELF eventsAmir Goldstein
We need to report FS_ISDIR flag with MOVE_SELF and DELETE_SELF events for fanotify, because fanotify API requires the user to explicitly request events on directories by FAN_ONDIR flag. inotify never reported IN_ISDIR with those events. It looks like an oversight, but to avoid the risk of breaking existing inotify programs, mask the FS_ISDIR flag out when reprting those events to inotify backend. We also add the FS_ISDIR flag with FS_ATTRIB event in the case of rename over an empty target directory. inotify did not report IN_ISDIR in this case, but it normally does report IN_ISDIR along with IN_ATTRIB event, so in this case, we do not mask out the FS_ISDIR flag. [JK: Simplify the checks in fsnotify_move()] Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: use vfs_get_fsid() helper instead of vfs_statfs()Amir Goldstein
This is a cleanup that doesn't change any logic. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: cache fsid in fsnotify_mark_connectorAmir Goldstein
For FAN_REPORT_FID, we need to encode fid with fsid of the filesystem on every event. To avoid having to call vfs_statfs() on every event to get fsid, we store the fsid in fsnotify_mark_connector on the first time we add a mark and on handle event we use the cached fsid. Subsequent calls to add mark on the same object are expected to pass the same fsid, so the call will fail on cached fsid mismatch. If an event is reported on several mark types (inode, mount, filesystem), all connectors should already have the same fsid, so we use the cached fsid from the first connector. [JK: Simplify code flow around fanotify_get_fid() make fsid argument of fsnotify_add_mark_locked() unconditional] Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: enable FAN_REPORT_FID init flagAmir Goldstein
When setting up an fanotify listener, user may request to get fid information in event instead of an open file descriptor. The fid obtained with event on a watched object contains the file handle returned by name_to_handle_at(2) and fsid returned by statfs(2). Restrict FAN_REPORT_FID to class FAN_CLASS_NOTIF, because we have have no good reason to support reporting fid on permission events. When setting a mark, we need to make sure that the filesystem supports encoding file handles with name_to_handle_at(2) and that statfs(2) encodes a non-zero fsid. Cc: <linux-api@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: copy event fid info to userAmir Goldstein
If group requested FAN_REPORT_FID and event has file identifier, copy that information to user reading the event after event metadata. fid information is formatted as struct fanotify_event_info_fid that includes a generic header struct fanotify_event_info_header, so that other info types could be defined in the future using the same header. metadata->event_len includes the length of the fid information. The fid information includes the filesystem's fsid (see statfs(2)) followed by an NFS file handle of the file that could be passed as an argument to open_by_handle_at(2). Cc: <linux-api@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: encode file identifier for FAN_REPORT_FIDAmir Goldstein
When user requests the flag FAN_REPORT_FID in fanotify_init(), a unique file identifier of the event target object will be reported with the event. The file identifier includes the filesystem's fsid (i.e. from statfs(2)) and an NFS file handle of the file (i.e. from name_to_handle_at(2)). The file identifier makes holding the path reference and passing a file descriptor to user redundant, so those are disabled in a group with FAN_REPORT_FID. Encode fid and store it in event for a group with FAN_REPORT_FID. Up to 12 bytes of file handle on 32bit arch (16 bytes on 64bit arch) are stored inline in fanotify_event struct. Larger file handles are stored in an external allocated buffer. On failure to encode fid, we print a warning and queue the event without the fid information. [JK: Fold part of later patched into this one to use exportfs_encode_inode_fh() right away] Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-07fanotify: open code fill_event_metadata()Amir Goldstein
The helper is quite trivial and open coding it will make it easier to implement copying event fid info to user. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-06fanotify: rename struct fanotify_{,perm_}event_infoAmir Goldstein
struct fanotify_event_info "inherits" from struct fsnotify_event and therefore a more appropriate (and short) name for it is fanotify_event. Same for struct fanotify_perm_event_info, which now "inherits" from struct fanotify_event. We plan to reuse the name struct fanotify_event_info for user visible event info record format. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-06fsnotify: move mask out of struct fsnotify_eventAmir Goldstein
Common fsnotify_event helpers have no need for the mask field. It is only used by backend code, so move the field out of the abstract fsnotify_event struct and into the concrete backend event structs. This change packs struct inotify_event_info better on 64bit machine and will allow us to cram some more fields into struct fanotify_event_info. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-06fsnotify: send all event types to super block marksAmir Goldstein
So far, existence of super block marks was checked only on events with data type FSNOTIFY_EVENT_PATH. Use the super block of the "to_tell" inode to report the events of all event types to super block marks. This change has no effect on current backends. Soon, this will allow fanotify backend to receive all event types on a super block mark. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-01-02inotify: Fix fd refcount leak in inotify_add_watch().Tetsuo Handa
Commit 4d97f7d53da7dc83 ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()") forgot to call fdput() before bailing out. Fixes: 4d97f7d53da7dc83 ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()") CC: stable@vger.kernel.org Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-11fanotify: Use inode_is_open_for_writeNikolay Borisov
Use the aptly named function rather than opencoding i_writecount check. No functional changes. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-05fanotify: Make sure to check event_len when copyingKees Cook
As a precaution, make sure we check event_len when copying to userspace. Based on old feedback: https://lkml.kernel.org/r/542D9FE5.3010009@gmx.de Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jan Kara <jack@suse.cz>
2018-11-15fsnotify/fdinfo: include fdinfo.h for inotify_show_fdinfo()Eric Biggers
inotify_show_fdinfo() is defined in fs/notify/fdinfo.c and declared in fs/notify/fdinfo.h, but the declaration isn't included at the point of the definition. Include the header to enforce that the definition matches the declaration. This addresses a gcc warning when -Wmissing-prototypes is enabled. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-11-13fanotify: introduce new event mask FAN_OPEN_EXEC_PERMMatthew Bobrowski
A new event mask FAN_OPEN_EXEC_PERM has been defined. This allows users to receive events and grant access to files that are intending to be opened for execution. Events of FAN_OPEN_EXEC_PERM type will be generated when a file has been opened by using either execve(), execveat() or uselib() system calls. This acts in the same manner as previous permission event mask, meaning that an access response is required from the user application in order to permit any further operations on the file. Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-11-13fanotify: introduce new event mask FAN_OPEN_EXECMatthew Bobrowski
A new event mask FAN_OPEN_EXEC has been defined so that users have the ability to receive events specifically when a file has been opened with the intent to be executed. Events of FAN_OPEN_EXEC type will be generated when a file has been opened using either execve(), execveat() or uselib() system calls. The feature is implemented within fsnotify_open() by generating the FAN_OPEN_EXEC event type if __FMODE_EXEC is set within file->f_flags. Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>