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path: root/fs/notify/fanotify/fanotify_user.c
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2019-03-19fanotify: Allow copying of file handle to userspaceJan Kara1-1/+11
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>
2019-02-18fanotify: Use interruptible wait when waiting for permission eventsJan Kara1-1/+8
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 Kara1-7/+28
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 Kara1-6/+4
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>
2019-02-18fanotify: Move locking inside get_one_event()Jan Kara1-19/+13
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 Kara1-28/+13
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>
2019-02-07fanotify: add support for create/attrib/move/delete eventsAmir Goldstein1-0/+12
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 Goldstein1-1/+2
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: use vfs_get_fsid() helper instead of vfs_statfs()Amir Goldstein1-15/+10
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 Goldstein1-25/+37
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 Goldstein1-1/+60
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 Goldstein1-5/+77
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 Goldstein1-4/+2
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 Goldstein1-44/+27
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 Goldstein1-10/+10
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 Goldstein1-5/+5
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>
2018-12-11fanotify: Use inode_is_open_for_writeNikolay Borisov1-1/+1
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 Cook1-2/+8
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>
2018-10-08fanotify: support reporting thread id instead of process idAmir Goldstein1-2/+2
In order to identify which thread triggered the event in a multi-threaded program, add the FAN_REPORT_TID flag in fanotify_init to opt-in for reporting the event creator's thread id information. Signed-off-by: nixiaoming <nixiaoming@huawei.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-10-04fanotify: add BUILD_BUG_ON() to count the bits of fanotify constantsAmir Goldstein1-1/+4
Also define the FANOTIFY_EVENT_FLAGS consisting of the extra flags FAN_ONDIR and FAN_ON_CHILD. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-10-04fanotify: deprecate uapi FAN_ALL_* constantsAmir Goldstein1-11/+11
We do not want to add new bits to the FAN_ALL_* uapi constants because they have been exposed to userspace. If there are programs out there using these constants, those programs could break if re-compiled with modified FAN_ALL_* constants and run on an old kernel. We deprecate the uapi constants FAN_ALL_* and define new FANOTIFY_* constants for internal use to replace them. New feature bits will be added only to the new constants. Cc: <linux-api@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-10-04fanotify: simplify handling of FAN_ONDIRAmir Goldstein1-27/+5
fanotify mark add/remove code jumps through hoops to avoid setting the FS_ISDIR in the commulative object mask. That was just papering over a bug in fsnotify() handling of the FS_ISDIR extra flag. This bug is now fixed, so all the hoops can be removed along with the unneeded internal flag FAN_MARK_ONDIR. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-09-27fanotify: store fanotify_init() flags in group's fanotify_dataAmir Goldstein1-4/+4
This averts the need to re-generate flags in fanotify_show_fdinfo() and sets the scene for addition of more upcoming flags without growing new members to the fanotify_data struct. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-09-03fanotify: add API to attach/detach super block markAmir Goldstein1-5/+37
Add another mark type flag FAN_MARK_FILESYSTEM for add/remove/flush of super block mark type. A super block watch gets all events on the filesystem, regardless of the mount from which the mark was added, unless an ignore mask exists on either the inode or the mount where the event was generated. Only one of FAN_MARK_MOUNT and FAN_MARK_FILESYSTEM mark type flags may be provided to fanotify_mark() or no mark type flag for inode mark. Cc: <linux-api@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-08-18Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-1/+4
Merge updates from Andrew Morton: - a few misc things - a few Y2038 fixes - ntfs fixes - arch/sh tweaks - ocfs2 updates - most of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (111 commits) mm/hmm.c: remove unused variables align_start and align_end fs/userfaultfd.c: remove redundant pointer uwq mm, vmacache: hash addresses based on pmd mm/list_lru: introduce list_lru_shrink_walk_irq() mm/list_lru.c: pass struct list_lru_node* as an argument to __list_lru_walk_one() mm/list_lru.c: move locking from __list_lru_walk_one() to its caller mm/list_lru.c: use list_lru_walk_one() in list_lru_walk_node() mm, swap: make CONFIG_THP_SWAP depend on CONFIG_SWAP mm/sparse: delete old sparse_init and enable new one mm/sparse: add new sparse_init_nid() and sparse_init() mm/sparse: move buffer init/fini to the common place mm/sparse: use the new sparse buffer functions in non-vmemmap mm/sparse: abstract sparse buffer allocations mm/hugetlb.c: don't zero 1GiB bootmem pages mm, page_alloc: double zone's batchsize mm/oom_kill.c: document oom_lock mm/hugetlb: remove gigantic page support for HIGHMEM mm, oom: remove sleep from under oom_lock kernel/dma: remove unsupported gfp_mask parameter from dma_alloc_from_contiguous() mm/cma: remove unsupported gfp_mask parameter from cma_alloc() ...
2018-08-18fs: fsnotify: account fsnotify metadata to kmemcgShakeel Butt1-1/+4
Patch series "Directed kmem charging", v8. The Linux kernel's memory cgroup allows limiting the memory usage of the jobs running on the system to provide isolation between the jobs. All the kernel memory allocated in the context of the job and marked with __GFP_ACCOUNT will also be included in the memory usage and be limited by the job's limit. The kernel memory can only be charged to the memcg of the process in whose context kernel memory was allocated. However there are cases where the allocated kernel memory should be charged to the memcg different from the current processes's memcg. This patch series contains two such concrete use-cases i.e. fsnotify and buffer_head. The fsnotify event objects can consume a lot of system memory for large or unlimited queues if there is either no or slow listener. The events are allocated in the context of the event producer. However they should be charged to the event consumer. Similarly the buffer_head objects can be allocated in a memcg different from the memcg of the page for which buffer_head objects are being allocated. To solve this issue, this patch series introduces mechanism to charge kernel memory to a given memcg. In case of fsnotify events, the memcg of the consumer can be used for charging and for buffer_head, the memcg of the page can be charged. For directed charging, the caller can use the scope API memalloc_[un]use_memcg() to specify the memcg to charge for all the __GFP_ACCOUNT allocations within the scope. This patch (of 2): A lot of memory can be consumed by the events generated for the huge or unlimited queues if there is either no or slow listener. This can cause system level memory pressure or OOMs. So, it's better to account the fsnotify kmem caches to the memcg of the listener. However the listener can be in a different memcg than the memcg of the producer and these allocations happen in the context of the event producer. This patch introduces remote memcg charging API which the producer can use to charge the allocations to the memcg of the listener. There are seven fsnotify kmem caches and among them allocations from dnotify_struct_cache, dnotify_mark_cache, fanotify_mark_cache and inotify_inode_mark_cachep happens in the context of syscall from the listener. So, SLAB_ACCOUNT is enough for these caches. The objects from fsnotify_mark_connector_cachep are not accounted as they are small compared to the notification mark or events and it is unclear whom to account connector to since it is shared by all events attached to the inode. The allocations from the event caches happen in the context of the event producer. For such caches we will need to remote charge the allocations to the listener's memcg. Thus we save the memcg reference in the fsnotify_group structure of the listener. This patch has also moved the members of fsnotify_group to keep the size same, at least for 64 bit build, even with additional member by filling the holes. [shakeelb@google.com: use GFP_KERNEL_ACCOUNT rather than open-coding it] Link: http://lkml.kernel.org/r/20180702215439.211597-1-shakeelb@google.com Link: http://lkml.kernel.org/r/20180627191250.209150-2-shakeelb@google.com Signed-off-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Greg Thelen <gthelen@google.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-27fanotify: factor out helpers to add/remove markAmir Goldstein1-57/+29
Factor out helpers fanotify_add_mark() and fanotify_remove_mark() to reduce duplicated code. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-06-27fsnotify: add helper to get mask from connectorAmir Goldstein1-8/+8
Use a helper to get the mask from the object (i.e. i_fsnotify_mask) to generalize code of add/remove inode/vfsmount mark. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-06-27fsnotify: pass connp and object type to fsnotify_add_mark()Amir Goldstein1-8/+11
Instead of passing inode and vfsmount arguments to fsnotify_add_mark() and its _locked variant, pass an abstract object pointer and the object type. The helpers fsnotify_obj_{inode,mount} are added to get the concrete object pointer from abstract object pointer. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-04-06Merge branch 'for_linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull misc filesystem updates from Jan Kara: "udf, ext2, quota, fsnotify fixes & cleanups: - udf fixes for handling of media without uid/gid - udf fixes for some corner cases in parsing of volume recognition sequence - improvements of fsnotify handling of ENOMEM - new ioctl to allow setting of watch descriptor id for inotify (for checkpoint - restart) - small ext2, reiserfs, quota cleanups" * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: quota: Kill an unused extern entry form quota.h reiserfs: Remove VLA from fs/reiserfs/reiserfs.h udf: fix potential refcnt problem of nls module ext2: change return code to -ENOMEM when failing memory allocation udf: Do not mark possibly inconsistent filesystems as closed fsnotify: Let userspace know about lost events due to ENOMEM fanotify: Avoid lost events due to ENOMEM for unlimited queues udf: Remove never implemented mount options udf: Update mount option documentation udf: Provide saner default for invalid uid / gid udf: Clean up handling of invalid uid/gid udf: Apply uid/gid mount options also to new inodes & chown udf: Ignore [ug]id=ignore mount options udf: Fix handling of Partition Descriptors udf: Unify common handling of descriptors udf: Convert descriptor index definitions to enum udf: Allow volume descriptor sequence to be terminated by unrecorded block udf: Simplify handling of Volume Descriptor Pointers udf: Fix off-by-one in volume descriptor sequence length inotify: Extend ioctl to allow to request id of new watch descriptor
2018-04-02fanotify: add do_fanotify_mark() helper; remove in-kernel call to syscallDominik Brodowski1-4/+10
Using the fs-internal do_fanotify_mark() helper allows us to get rid of the fs-internal call to the sys_fanotify_mark() syscall. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Acked-by: Jan Kara <jack@suse.cz> Cc: Amir Goldstein <amir73il@gmail.com> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-02-27fanotify: Avoid lost events due to ENOMEM for unlimited queuesJan Kara1-1/+1
Fanotify queues of unlimited length do not expect events can be lost. Since these queues are used for system auditing and other security related tasks, loosing events can even have security implications. Currently, since the allocation is small (32-bytes), it cannot fail however when we start accounting events in memcgs, allocation can start failing. So avoid loosing events due to failure to allocate memory by making event allocation use __GFP_NOFAIL. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-02-12vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds1-1/+1
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-28fs: annotate ->poll() instancesAl Viro1-2/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-15Merge branch 'for_linus' of ↵Linus Torvalds1-1/+15
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 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
2017-11-15Merge branch 'fsnotify' of ↵Linus Torvalds1-27/+16
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 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()
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+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>
2017-10-31fanotify: clean up CONFIG_FANOTIFY_ACCESS_PERMISSIONS ifdefsMiklos Szeredi1-27/+16
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 <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-10-10audit: Record fanotify access control decisionsSteve Grubb1-1/+15
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 <sgrubb@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-25fanotify: don't expose EOPENSTALE to userspaceAmir Goldstein1-8/+18
When delivering an event to userspace for a file on an NFS share, if the file is deleted on server side before user reads the event, user will not get the event. If the event queue contained several events, the stale event is quietly dropped and read() returns to user with events read so far in the buffer. If the event queue contains a single stale event or if the stale event is a permission event, read() returns to user with the kernel internal error code 518 (EOPENSTALE), which is not a POSIX error code. Check the internal return value -EOPENSTALE in fanotify_read(), just the same as it is checked in path_openat() and drop the event in the cases that it is not already dropped. This is a reproducer from Marko Rauhamaa: Just take the example program listed under "man fanotify" ("fantest") and follow these steps: ============================================================== NFS Server NFS Client(1) NFS Client(2) ============================================================== # echo foo >/nfsshare/bar.txt # cat /nfsshare/bar.txt foo # ./fantest /nfsshare Press enter key to terminate. Listening for events. # rm -f /nfsshare/bar.txt # cat /nfsshare/bar.txt read: Unknown error 518 cat: /nfsshare/bar.txt: Operation not permitted ============================================================== where NFS Client (1) and (2) are two terminal sessions on a single NFS Client machine. Reported-by: Marko Rauhamaa <marko.rauhamaa@f-secure.com> Tested-by: Marko Rauhamaa <marko.rauhamaa@f-secure.com> Cc: <linux-api@vger.kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10fsnotify: Move ->free_mark callback to fsnotify_opsJan Kara1-7/+2
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 <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10fsnotify: Add group pointer in fsnotify_init_mark()Jan Kara1-2/+2
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 <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10fsnotify: Remove fsnotify_find_{inode|vfsmount}_mark()Jan Kara1-5/+7
These are very thin wrappers, just remove them. Drop fs/notify/vfsmount_mark.c as it is empty now. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10fsnotify: Remove fsnotify_recalc_{inode|vfsmount}_mask()Jan Kara1-4/+4
These helpers are just very thin wrappers now. Remove them. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10fsnotify: Remove fsnotify_set_mark_{,ignored_}mask_locked()Jan Kara1-5/+4
These helpers are now only a simple assignment and just obfuscate what is going on. Remove them. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-03fanotify: Move recalculation of inode / vfsmount mask under mark_mutexJan Kara1-9/+6
Move recalculation of inode / vfsmount notification mask under group->mark_mutex of the mark which was modified. These are the only places where mask recalculation happens without mark being protected from detaching from inode / vfsmount which will cause issues with the following patches. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar1-0/+1
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-08fsnotify: clean up spinlock assertionsJan Kara1-2/+1
Use assert_spin_locked() macro instead of hand-made BUG_ON statements. Link: http://lkml.kernel.org/r/1474537439-18919-1-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Suggested-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-08fanotify: use notification_lock instead of access_lockJan Kara1-8/+5
Fanotify code has its own lock (access_lock) to protect a list of events waiting for a response from userspace. However this is somewhat awkward as the same list_head in the event is protected by notification_lock if it is part of the notification queue and by access_lock if it is part of the fanotify private queue which makes it difficult for any reliable checks in the generic code. So make fanotify use the same lock - notification_lock - for protecting its private event list. Link: http://lkml.kernel.org/r/1473797711-14111-6-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Eric Paris <eparis@redhat.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-08fsnotify: convert notification_mutex to a spinlockJan Kara1-13/+14
notification_mutex is used to protect the list of pending events. As such there's no reason to use a sleeping lock for it. Convert it to a spinlock. [jack@suse.cz: fixed version] Link: http://lkml.kernel.org/r/1474031567-1831-1-git-send-email-jack@suse.cz Link: http://lkml.kernel.org/r/1473797711-14111-5-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Eric Paris <eparis@redhat.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>