summaryrefslogtreecommitdiffstats
path: root/fs/notify/fanotify
Commit message (Collapse)AuthorAgeFilesLines
* Merge branch 'master' into for-nextJiri Kosina2010-12-222-31/+56
|\ | | | | | | | | | | | | | | | | | | Conflicts: MAINTAINERS arch/arm/mach-omap2/pm24xx.c drivers/scsi/bfa/bfa_fcpim.c Needed to update to apply fixes for which the old branch was too outdated.
| * fanotify: fill in the metadata_len field on struct fanotify_event_metadataEric Paris2010-12-151-2/+4
| | | | | | | | | | | | | | | | | | The fanotify_event_metadata now has a field which is supposed to indicate the length of the metadata portion of the event. Fill in that field as well. Based-in-part-on-patch-by: Alexey Zaytsev <alexey.zaytsev@gmail.com> Signed-off-by: Eric Paris <eparis@redhat.com>
| * fanotify: Dont try to open a file descriptor for the overflow eventLino Sanfilippo2010-12-071-4/+13
| | | | | | | | | | | | | | | | We should not try to open a file descriptor for the overflow event since this will always fail. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Signed-off-by: Eric Paris <eparis@redhat.com>
| * fanotify: do not leak user reference on allocation failureEric Paris2010-12-071-1/+3
| | | | | | | | | | | | | | | | | | If fanotify_init is unable to allocate a new fsnotify group it will return but will not drop its reference on the associated user struct. Drop that reference on error. Reported-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Eric Paris <eparis@redhat.com>
| * fanotify: on group destroy allow all waiters to bypass permission checkLino Sanfilippo2010-12-072-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When fanotify_release() is called, there may still be processes waiting for access permission. Currently only processes for which an event has already been queued into the groups access list will be woken up. Processes for which no event has been queued will continue to sleep and thus cause a deadlock when fsnotify_put_group() is called. Furthermore there is a race allowing further processes to be waiting on the access wait queue after wake_up (if they arrive before clear_marks_by_group() is called). This patch corrects this by setting a flag to inform processes that the group is about to be destroyed and thus not to wait for access permission. [additional changelog from eparis] Lets think about the 4 relevant code paths from the PoV of the 'operator' 'listener' 'responder' and 'closer'. Where operator is the process doing an action (like open/read) which could require permission. Listener is the task (or in this case thread) slated with reading from the fanotify file descriptor. The 'responder' is the thread responsible for responding to access requests. 'Closer' is the thread attempting to close the fanotify file descriptor. The 'operator' is going to end up in: fanotify_handle_event() get_response_from_access() (THIS BLOCKS WAITING ON USERSPACE) The 'listener' interesting code path fanotify_read() copy_event_to_user() prepare_for_access_response() (THIS CREATES AN fanotify_response_event) The 'responder' code path: fanotify_write() process_access_response() (REMOVE A fanotify_response_event, SET RESPONSE, WAKE UP 'operator') The 'closer': fanotify_release() (SUPPOSED TO CLEAN UP THE REST OF THIS MESS) What we have today is that in the closer we remove all of the fanotify_response_events and set a bit so no more response events are ever created in prepare_for_access_response(). The bug is that we never wake all of the operators up and tell them to move along. You fix that in fanotify_get_response_from_access(). You also fix other operators which haven't gotten there yet. So I agree that's a good fix. [/additional changelog from eparis] [remove additional changes to minimize patch size] [move initialization so it was inside CONFIG_FANOTIFY_PERMISSION] Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Signed-off-by: Eric Paris <eparis@redhat.com>
| * fanotify: Dont allow a mask of 0 if setting or removing a markLino Sanfilippo2010-12-071-1/+3
| | | | | | | | | | | | | | | | | | | | | | In mark_remove_from_mask() we destroy marks that have their event mask cleared. Thus we should not allow the creation of those marks in the first place. With this patch we check if the mask given from user is 0 in case of FAN_MARK_ADD. If so we return an error. Same for FAN_MARK_REMOVE since this does not have any effect. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Signed-off-by: Eric Paris <eparis@redhat.com>
| * fanotify: correct broken ref counting in case adding a mark failedLino Sanfilippo2010-12-071-17/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If adding a mount or inode mark failed fanotify_free_mark() is called explicitly. But at this time the mark has already been put into the destroy list of the fsnotify_mark kernel thread. If the thread is too slow it will try to decrease the reference of a mark, that has already been freed by fanotify_free_mark(). (If its fast enough it will only decrease the marks ref counter from 2 to 1 - note that the counter has been increased to 2 in add_mark() - which has practically no effect.) This patch fixes the ref counting by not calling free_mark() explicitly, but decreasing the ref counter and rely on the fsnotify_mark thread to cleanup in case adding the mark has failed. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Signed-off-by: Eric Paris <eparis@redhat.com>
| * fanotify: deny permissions when no event was sentEric Paris2010-12-071-4/+12
| | | | | | | | | | | | | | | | | | If no event was sent to userspace we cannot expect userspace to respond to permissions requests. Today such requests just hang forever. This patch will deny any permissions event which was unable to be sent to userspace. Reported-by: Tvrtko Ursulin <tvrtko.ursulin@sophos.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* | Kconfig: typo: and -> anMichael Witten2010-11-011-1/+1
|/ | | | | Signed-off-by: Michael Witten <mfwitten@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* make fanotify_read() restartable across signalsLino Sanfilippo2010-10-301-1/+1
| | | | | | | In fanotify_read() return -ERESTARTSYS instead of -EINTR to make read() restartable across signals (BSD semantic). Signed-off-by: Eric Paris <eparis@redhat.com>
* fs/notify/fanotify/fanotify_user.c: fix warningsAndrew Morton2010-10-281-3/+2
| | | | | | | | | | | | fs/notify/fanotify/fanotify_user.c: In function 'fanotify_release': fs/notify/fanotify/fanotify_user.c:375: warning: unused variable 'lre' fs/notify/fanotify/fanotify_user.c:375: warning: unused variable 're' this is really ugly. Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not recalculate the mask if the ignored mask changedEric Paris2010-10-281-3/+3
| | | | | | | | If fanotify sets a new bit in the ignored mask it will cause the generic fsnotify layer to recalculate the real mask. This is stupid since we didn't change that part. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: ignore events on directories unless specifically requestedEric Paris2010-10-282-0/+17
| | | | | | | | | | | | | | fanotify has a very limited number of events it sends on directories. The usefulness of these events is yet to be seen and still we send them. This is particularly painful for mount marks where one might receive many of these useless events. As such this patch will drop events on IS_DIR() inodes unless they were explictly requested with FAN_ON_DIR. This means that a mark on a directory without FAN_EVENT_ON_CHILD or FAN_ON_DIR is meaningless and will result in no events ever (although it will still be allowed since detecting it is hard) Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not send events for irregular filesEric Paris2010-10-281-5/+6
| | | | | | | | | | fanotify_should_send_event has a test to see if an object is a file or directory and does not send an event otherwise. The problem is that the test is actually checking if the object with a mark is a file or directory, not if the object the event happened on is a file or directory. We should check the latter. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: limit number of listeners per userEric Paris2010-10-282-1/+21
| | | | | | | | fanotify currently has no limit on the number of listeners a given user can have open. This patch limits the total number of listeners per user to 128. This is the same as the inotify default limit. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: allow userspace to override max marksEric Paris2010-10-281-1/+8
| | | | | | | | | | | | Some fanotify groups, especially those like AV scanners, will need to place lots of marks, particularly ignore marks. Since ignore marks do not pin inodes in cache and are cleared if the inode is removed from core (usually under memory pressure) we expose an interface for listeners, with CAP_SYS_ADMIN, to override the maximum number of marks and be allowed to set and 'unlimited' number of marks. Programs which make use of this feature will be able to OOM a machine. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: limit the number of marks in a single fanotify groupEric Paris2010-10-281-0/+9
| | | | | | | | | | There is currently no limit on the number of marks a given fanotify group can have. Since fanotify is gated on CAP_SYS_ADMIN this was not seen as a serious DoS threat. This patch implements a default of 8192, the same as inotify to work towards removing the CAP_SYS_ADMIN gating and eliminating the default DoS'able status. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: allow userspace to override max queue depthEric Paris2010-10-281-1/+8
| | | | | | | | | fanotify has a defualt max queue depth. This patch allows processes which explicitly request it to have an 'unlimited' queue depth. These processes need to be very careful to make sure they cannot fall far enough behind that they OOM the box. Thus this flag is gated on CAP_SYS_ADMIN. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: implement a default maximum queue depthEric Paris2010-10-281-0/+4
| | | | | | | | | | | | Currently fanotify has no maximum queue depth. Since fanotify is CAP_SYS_ADMIN only this does not pose a normal user DoS issue, but it certianly is possible that an fanotify listener which can't keep up could OOM the box. This patch implements a default 16k depth. This is the same default depth used by inotify, but given fanotify's better queue merging in many situations this queue will contain many additional useful events by comparison. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: ignore fanotify ignore marks if open writersEric Paris2010-10-281-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fanotify will clear ignore marks if a task changes the contents of an inode. The problem is with the races around when userspace finishes checking a file and when that result is actually attached to the inode. This race was described as such: Consider the following scenario with hostile processes A and B, and victim process C: 1. Process A opens new file for writing. File check request is generated. 2. File check is performed in userspace. Check result is "file has no malware". 3. The "permit" response is delivered to kernel space. 4. File ignored mark set. 5. Process A writes dummy bytes to the file. File ignored flags are cleared. 6. Process B opens the same file for reading. File check request is generated. 7. File check is performed in userspace. Check result is "file has no malware". 8. Process A writes malware bytes to the file. There is no cached response yet. 9. The "permit" response is delivered to kernel space and is cached in fanotify. 10. File ignored mark set. 11. Now any process C will be permitted to open the malware file. There is a race between steps 8 and 10 While fanotify makes no strong guarantees about systems with hostile processes there is no reason we cannot harden against this race. We do that by simply ignoring any ignore marks if the inode has open writers (aka i_writecount > 0). (We actually do not ignore ignore marks if the FAN_MARK_SURV_MODIFY flag is set) Reported-by: Vasily Novikov <vasily.novikov@kaspersky.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: implement fanotify listener orderingEric Paris2010-10-281-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fanotify listeners needs to be able to specify what types of operations they are going to perform so they can be ordered appropriately between other listeners doing other types of operations. They need this to be able to make sure that things like hierarchichal storage managers will get access to inodes before processes which need the data. This patch defines 3 possible uses which groups must indicate in the fanotify_init() flags. FAN_CLASS_PRE_CONTENT FAN_CLASS_CONTENT FAN_CLASS_NOTIF Groups will receive notification in that order. The order between 2 groups in the same class is undeterministic. FAN_CLASS_PRE_CONTENT is intended to be used by listeners which need access to the inode before they are certain that the inode contains it's final data. A hierarchical storage manager should choose to use this class. FAN_CLASS_CONTENT is intended to be used by listeners which need access to the inode after it contains its intended contents. This would be the appropriate level for an AV solution or document control system. FAN_CLASS_NOTIF is intended for normal async notification about access, much the same as inotify and dnotify. Syncronous permissions events are not permitted at this class. Signed-off-by: Eric Paris <eparis@redhat.com>
* llseek: automatically add .llseek fopArnd Bergmann2010-10-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
* fanotify: Return EPERM when a process is not privilegedAndreas Gruenbacher2010-08-271-1/+1
| | | | | | | | The appropriate error code when privileged operations are denied is EPERM, not EACCES. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <paris@paris.rdu.redhat.com>
* fanotify: drop duplicate pr_debug statementTvrtko Ursulin2010-08-221-3/+0
| | | | | | | | | | This reminded me... you have two pr_debugs in fanotify_should_send_event which output redundant information. Maybe you intended it like that so it is selectable how much log spam you want, or if not you may want to apply this patch. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@sophos.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: flush outstanding perm requests on group destroyEric Paris2010-08-221-0/+27
| | | | | | | | | | | | | | | When an fanotify listener is closing it may cause a deadlock between the listener and the original task doing an fs operation. If the original task is waiting for a permissions response it will be holding the srcu lock. The listener cannot clean up and exit until after that srcu lock is syncronized. Thus deadlock. The fix introduced here is to stop accepting new permissions events when a listener is shutting down and to grant permission for all outstanding events. Thus the original task will eventually release the srcu lock and the listener can complete shutdown. Reported-by: Andreas Gruenbacher <agruen@suse.de> Cc: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* Revert "fsnotify: store struct file not struct path"Linus Torvalds2010-08-122-7/+7
| | | | | | | | | | | | | | | This reverts commit 3bcf3860a4ff9bbc522820b4b765e65e4deceb3e (and the accompanying commit c1e5c954020e "vfs/fsnotify: fsnotify_close can delay the final work in fput" that was a horribly ugly hack to make it work at all). The 'struct file' approach not only causes that disgusting hack, it somehow breaks pulseaudio, probably due to some other subtlety with f_count handling. Fix up various conflicts due to later fsnotify work. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fanotify: use both marks when possibleEric Paris2010-07-281-54/+34
| | | | | | | | fanotify currently, when given a vfsmount_mark will look up (if it exists) the corresponding inode mark. This patch drops that lookup and uses the mark provided. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: pass both the vfsmount mark and inode markEric Paris2010-07-281-5/+10
| | | | | | | | should_send_event() and handle_event() will both need to look up the inode event if they get a vfsmount event. Lets just pass both at the same time since we have them both after walking the lists in lockstep. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: remove group->maskEric Paris2010-07-281-18/+5
| | | | | | | group->mask is now useless. It was originally a shortcut for fsnotify to save on performance. These checks are now redundant, so we remove them. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: cleanup should_send_eventEric Paris2010-07-281-15/+8
| | | | | | | | The change to use srcu and walk the object list rather than the global fsnotify_group list means that should_send_event is no longer needed for a number of groups and can be simplified for others. Do that. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: use the mark in handler functionsEric Paris2010-07-281-29/+17
| | | | | | | | fanotify now gets a mark in the should_send_event and handle_event functions. Rather than look up the mark themselves fanotify should just use the mark it was handed. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: send fsnotify_mark to groups in event handling functionsEric Paris2010-07-281-3/+5
| | | | | | | | | With the change of fsnotify to use srcu walking the marks list instead of walking the global groups list we now know the mark in question. The code can send the mark to the group's handling functions and the groups won't have to find those marks themselves. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: store struct file not struct pathEric Paris2010-07-282-7/+7
| | | | | | | | | Al explains that calling dentry_open() with a mnt/dentry pair is only garunteed to be safe if they are already used in an open struct file. To make sure this is the case don't store and use a struct path in fsnotify, always use a struct file. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: fsnotify_add_notify_event should return an eventEric Paris2010-07-281-57/+46
| | | | | | | | | Rather than the horrific void ** argument and such just to pass the fanotify_merge event back to the caller of fsnotify_add_notify_event() have those things return an event if it was different than the event suggusted to be added. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: groups can specify their f_flags for new fdEric Paris2010-07-281-4/+2
| | | | | | | | | Currently fanotify fds opened for thier listeners are done with f_flags equal to O_RDONLY | O_LARGEFILE. This patch instead takes f_flags from the fanotify_init syscall and uses those when opening files in the context of the listener. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: update gfp/slab.h includesTejun Heo2010-07-281-0/+1
| | | | | | | | | | Implicit slab.h inclusion via percpu.h is about to go away. Make sure gfp.h or slab.h is included as necessary. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: drop the useless priority argumentEric Paris2010-07-281-5/+3
| | | | | | The priority argument in fanotify is useless. Kill it. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: default Kconfig to nEric Paris2010-07-281-1/+1
| | | | | | | fanotify has default to y in linux-next since it's inception but default to n in the final push to Linus. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not return 0 in a void functionEric Paris2010-07-281-1/+1
| | | | | | | | remove_access_response() is supposed to have a void return, but was returning 0; Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: userspace interface for permission responsesEric Paris2010-07-282-6/+179
| | | | | | | | fanotify groups need to respond to events which include permissions types. To do so groups will send a response using write() on the fanotify_fd they have open. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: permissions and blockingEric Paris2010-07-283-4/+69
| | | | | | | | | This is the backend work needed for fanotify to support the new FS_OPEN_PERM and FS_ACCESS_PERM fsnotify events. This is done using the new fsnotify secondary queue. No userspace interface is provided actually respond to or request these events. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: use merge argument to determine actual event added to queueEric Paris2010-07-281-5/+16
| | | | | | | | | fanotify needs to know the actual event added to queues so it can be correctly checked for return values from userspace. To do this we need to pass that information from the merger code back to the main even handling routine. Currently that information is unused, but it will be. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: intoduce a notification merge argumentEric Paris2010-07-281-2/+4
| | | | | | | | | | | | | Each group can define their own notification (and secondary_q) merge function. Inotify does tail drop, fanotify does matching and drop which can actually allocate a completely new event. But for fanotify to properly deal with permissions events it needs to know the new event which was ultimately added to the notification queue. This patch just implements a void ** argument which is passed to the merge function. fanotify can use this field to pass the new event back to higher layers. Signed-off-by: Eric Paris <eparis@redhat.com> for fanotify to properly deal with permissions events
* fsnotify: add group prioritiesEric Paris2010-07-281-2/+2
| | | | | | | | | | | | | | | | This introduces an ordering to fsnotify groups. With purely asynchronous notification based "things" implementing fsnotify (inotify, dnotify) ordering isn't particularly important. But if people want to use fsnotify for the basis of sycronous notification or blocking notification ordering becomes important. eg. A Hierarchical Storage Management listener would need to get its event before an AV scanner could get its event (since the HSM would need to bring the data in for the AV scanner to scan.) Typically asynchronous notification would want to run after the AV scanner made any relevant access decisions so as to not send notification about an event that was denied. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: clear all fanotify marksEric Paris2010-07-281-2/+10
| | | | | | | | | fanotify listeners may want to clear all marks. They may want to do this to destroy all of their inode marks which have nothing but ignores. Realistically this is useful for av vendors who update policy and want to clear all of their cached allows. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: allow ignored_masks to survive modifyEric Paris2010-07-281-0/+2
| | | | | | | | | Some users may want to truely ignore an inode even if it has been modified. Say you are wanting a mount which contains a log file and you really don't want any notification about that file. This patch allows the listener to do that. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: allow users to set an ignored_maskEric Paris2010-07-281-18/+36
| | | | | | | | | | Change the sys_fanotify_mark() system call so users can set ignored_masks on inodes. Remember, if a user new sets a real mask, and only sets ignored masks, the ignore will never be pinned in memory. Thus ignored_masks can be lost under memory pressure and the user may again get events they previously thought were ignored. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: ignored_mask to ignore eventsEric Paris2010-07-281-14/+23
| | | | | | | When fanotify receives an event it will check event->mask & ~ignored_mask. If no bits are left the event will not be sent. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: allow marks to not pin inodes in coreEric Paris2010-07-281-2/+2
| | | | | | | | | | | | | | | | | inotify marks must pin inodes in core. dnotify doesn't technically need to since they are closed when the directory is closed. fanotify also need to pin inodes in core as it works today. But the next step is to introduce the concept of 'ignored masks' which is actually a mask of events for an inode of no interest. I claim that these should be liberally sent to the kernel and should not pin the inode in core. If the inode is brought back in the listener will get an event it may have thought excluded, but this is not a serious situation and one any listener should deal with. This patch lays the ground work for non-pinning inode marks by using lazy inode pinning. We do not pin a mark until it has a non-zero mask entry. If a listener new sets a mask we never pin the inode. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: remove outgoing function checks in fanotify.hAndreas Gruenbacher2010-07-283-16/+4
| | | | | | | | | A number of validity checks on outgoing data are done in static inlines but are only used in one place. Instead just do them where they are used for readability. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-25 17:16:23 +0000