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2022-04-25audit: use fsnotify group lock helpersAmir Goldstein
audit inode marks pin the inode so there is no need to set the FSNOTIFY_GROUP_NOFS flag. Link: https://lore.kernel.org/r/20220422120327.3459282-9-amir73il@gmail.com Suggested-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/ Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2022-04-25fsnotify: pass flags argument to fsnotify_alloc_group()Amir Goldstein
Add flags argument to fsnotify_alloc_group(), define and use the flag FSNOTIFY_GROUP_USER in inotify and fanotify instead of the helper fsnotify_alloc_user_group() to indicate user allocation. Although the flag FSNOTIFY_GROUP_USER is currently not used after group allocation, we store the flags argument in the group struct for future use of other group flags. Link: https://lore.kernel.org/r/20220422120327.3459282-5-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2021-12-14audit: use struct_size() helper in kmalloc()Xiu Jianfeng
Make use of struct_size() helper instead of an open-coded calucation. Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-11-01Merge tag 'audit-pr-20211101' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "Add some additional audit logging to capture the openat2() syscall open_how struct info. Previous variations of the open()/openat() syscalls allowed audit admins to inspect the syscall args to get the information contained in the new open_how struct used in openat2()" * tag 'audit-pr-20211101' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: return early if the filter rule has a lower priority audit: add OPENAT2 record to list "how" info audit: add support for the openat2 syscall audit: replace magic audit syscall class numbers with macros lsm_audit: avoid overloading the "key" audit field audit: Convert to SPDX identifier audit: rename struct node to struct audit_node to prevent future name collisions
2021-09-19audit: add filtering for io_uring recordsPaul Moore
This patch adds basic audit io_uring filtering, using as much of the existing audit filtering infrastructure as possible. In order to do this we reuse the audit filter rule's syscall mask for the io_uring operation and we create a new filter for io_uring operations as AUDIT_FILTER_URING_EXIT/audit_filter_list[7]. Thanks to Richard Guy Briggs for his review, feedback, and work on the corresponding audit userspace changes. Acked-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-09-13audit: rename struct node to struct audit_node to prevent future name collisionsChristophe Leroy
Future work in the powerpc code results in a name collision with the identified "node" as struct node defined in kernel/audit_tree.c conflicts with struct node defined in include/linux/node.h (below). This patch takes the proactive route and renames the audit code's struct node to audit_node. CC kernel/audit_tree.o kernel/audit_tree.c:33:9: error: redefinition of 'struct node' 33 | struct node { | ^~~~ In file included from ./include/linux/cpu.h:17, from ./include/linux/static_call.h:102, from ./arch/powerpc/include/asm/machdep.h:10, from ./arch/powerpc/include/asm/archrandom.h:7, from ./include/linux/random.h:121, from ./include/linux/net.h:18, from ./include/linux/skbuff.h:26, from kernel/audit.h:11, from kernel/audit_tree.c:2: ./include/linux/node.h:84:8: note: originally defined here 84 | struct node { | ^~~~ make[2]: *** [kernel/audit_tree.o] Error 1 Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> [PM: rewrite subj/desc as the build failure is just a RFC patch] Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-08-24audit: move put_tree() to avoid trim_trees refcount underflow and UAFRichard Guy Briggs
AUDIT_TRIM is expected to be idempotent, but multiple executions resulted in a refcount underflow and use-after-free. git bisect fingered commit fb041bb7c0a9 ("locking/refcount: Consolidate implementations of refcount_t") but this patch with its more thorough checking that wasn't in the x86 assembly code merely exposed a previously existing tree refcount imbalance in the case of tree trimming code that was refactored with prune_one() to remove a tree introduced in commit 8432c7006297 ("audit: Simplify locking around untag_chunk()") Move the put_tree() to cover only the prune_one() case. Passes audit-testsuite and 3 passes of "auditctl -t" with at least one directory watch. Cc: Jan Kara <jack@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Seiji Nishikawa <snishika@redhat.com> Cc: stable@vger.kernel.org Fixes: 8432c7006297 ("audit: Simplify locking around untag_chunk()") Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> [PM: reformatted/cleaned-up the commit description] Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-06-08audit: Use list_move instead of list_del/list_addBaokun Li
Using list_move() instead of list_del() + list_add(). Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Acked-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-12-03fsnotify: generalize handle_inode_event()Amir Goldstein
The handle_inode_event() interface was added as (quoting comment): "a simple variant of handle_event() for groups that only have inode marks and don't have ignore mask". In other words, all backends except fanotify. The inotify backend also falls under this category, but because it required extra arguments it was left out of the initial pass of backends conversion to the simple interface. This results in code duplication between the generic helper fsnotify_handle_event() and the inotify_handle_event() callback which also happen to be buggy code. Generalize the handle_inode_event() arguments and add the check for FS_EXCL_UNLINK flag to the generic helper, so inotify backend could be converted to use the simple interface. Link: https://lore.kernel.org/r/20201202120713.702387-2-amir73il@gmail.com CC: stable@vger.kernel.org Fixes: b9a1b9772509 ("fsnotify: create method handle_inode_event() in fsnotify_operations") Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-08-06Merge tag 'fsnotify_for_v5.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: - fanotify fix for softlockups when there are many queued events - performance improvement to reduce fsnotify overhead when not used - Amir's implementation of fanotify events with names. With these you can now efficiently monitor whole filesystem, eg to mirror changes to another machine. * tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (37 commits) fanotify: compare fsid when merging name event fsnotify: create method handle_inode_event() in fsnotify_operations fanotify: report parent fid + child fid fanotify: report parent fid + name + child fid fanotify: add support for FAN_REPORT_NAME fanotify: report events with parent dir fid to sb/mount/non-dir marks fanotify: add basic support for FAN_REPORT_DIR_FID fsnotify: remove check that source dentry is positive fsnotify: send event with parent/name info to sb/mount/non-dir marks audit: do not set FS_EVENT_ON_CHILD in audit marks mask inotify: do not set FS_EVENT_ON_CHILD in non-dir mark mask fsnotify: pass dir and inode arguments to fsnotify() fsnotify: create helper fsnotify_inode() fsnotify: send event to parent and child with single callback inotify: report both events on parent and child with single callback dnotify: report both events on parent and child with single callback fanotify: no external fh buffer in fanotify_name_event fanotify: use struct fanotify_info to parcel the variable size buffer fsnotify: add object type "child" to object type iterator fanotify: use FAN_EVENT_ON_CHILD as implicit flag on sb/mount/non-dir marks ...
2020-07-27fsnotify: create method handle_inode_event() in fsnotify_operationsAmir Goldstein
The method handle_event() grew a lot of complexity due to the design of fanotify and merging of ignore masks. Most backends do not care about this complex functionality, so we can hide this complexity from them. Introduce a method handle_inode_event() that serves those backends and passes a single inode mark and less arguments. This change converts all backends except fanotify and inotify to use the simplified handle_inode_event() method. In pricipal, inotify could have also used the new method, but that would require passing more arguments on the simple helper (data, data_type, cookie), so we leave it with the handle_event() method. Link: https://lore.kernel.org/r/20200722125849.17418-9-amir73il@gmail.com Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-07-27fsnotify: pass dir argument to handle_event() callbackAmir Goldstein
The 'inode' argument to handle_event(), sometimes referred to as 'to_tell' is somewhat obsolete. It is a remnant from the times when a group could only have an inode mark associated with an event. We now pass an iter_info array to the callback, with all marks associated with an event. Most backends ignore this argument, with two exceptions: 1. dnotify uses it for sanity check that event is on directory 2. fanotify uses it to report fid of directory on directory entry modification events Remove the 'inode' argument and add a 'dir' argument. The callback function signature is deliberately changed, because the meaning of the argument has changed and the arguments have been documented. The 'dir' argument is set to when 'file_name' is specified and it is referring to the directory that the 'file_name' entry belongs to. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-06-17audit: Use struct_size() helper in alloc_chunkGustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct audit_chunk { ... struct node { struct list_head list; struct audit_tree *owner; unsigned index; /* index; upper bit indicates 'will prune' */ } owners[]; }; Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. So, replace the following form: offsetof(struct audit_chunk, owners) + count * sizeof(struct node); with: struct_size(chunk, owners, count) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
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>
2019-01-14audit: hand taken context to audit_kill_trees for syscall loggingRichard Guy Briggs
Since the context is derived from the task parameter handed to __audit_free(), hand the context to audit_kill_trees() so it can be used to associate with a syscall record. This requires adding the context parameter to kill_rules() rather than using the current audit_context. The callers of trim_marked() and evict_chunk() still have their context. The EOE record was being issued prior to the pruning of the killed_tree list. Move the kill_trees call before the audit_log_exit call in __audit_free() and __audit_syscall_exit() so that any pruned trees CONFIG_CHANGE records are included with the associated syscall event by the user library due to the EOE record flagging the end of the event. See: https://github.com/linux-audit/audit-kernel/issues/50 See: https://github.com/linux-audit/audit-kernel/issues/59 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: fixed merge fuzz in kernel/audit_tree.c] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-26audit: minimize our use of audit_log_format()Paul Moore
There are some cases where we are making multiple audit_log_format() calls in a row, for no apparent reason. Squash these down to a single audit_log_format() call whenever possible. Acked-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Use 'mark' name for fsnotify_mark variablesJan Kara
Variables pointing to fsnotify_mark are sometimes called 'entry' and sometimes 'mark'. Use 'mark' in all places. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> [PM: minor merge fuzz due to updated patches previously in the series] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Replace chunk attached to mark instead of replacing markJan Kara
Audit tree code currently associates new fsnotify mark with each new chunk. As chunk attached to an inode is replaced when new tag is added / removed, we also need to remove old fsnotify mark and add a new one on such occasion. This is cumbersome and makes locking rules somewhat difficult to follow. Fix these problems by allocating fsnotify mark independently of chunk and keeping it all the time while there is some chunk attached to an inode. Also add documentation about the locking rules so that things are easier to follow. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> [PM: minor merge fuzz due to updated patches previously in the series] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Simplify locking around untag_chunk()Jan Kara
untag_chunk() has to be called with hash_lock, it drops it and reacquires it when returning. The unlocking of hash_lock is thus hidden from the callers of untag_chunk() with is rather error prone. Reorganize the code so that untag_chunk() is called without hash_lock, only with mark reference preventing the chunk from going away. Since this requires some more code in the caller of untag_chunk() to assure forward progress, factor out loop pruning tree from all chunks into a common helper function. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Drop all unused chunk nodes during deletionJan Kara
When deleting chunk from a tree, drop all unused nodes in a chunk instead of just the one used by the tree. This gets rid of possibly lingering unused nodes (created due to fallback path in untag_chunk()) and also removes some special cases and will allow us to simplify locking in untag_chunk(). Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Guarantee forward progress of chunk untaggingJan Kara
When removing chunk from a tree, we do shrink the chunk. This can fail for various reasons (due to races, ENOMEM, etc.) and in some cases we just bail from untag_chunk() relying on someone else to cleanup. Although this currently works, later we will need to add new failure situation which would break. Also this simplifies the code and will allow us to make locking around untag_chunk() less awkward. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Allocate fsnotify mark independently of chunkJan Kara
Allocate fsnotify mark independently instead of embedding it inside chunk. This will allow us to just replace chunk attached to mark when growing / shrinking chunk instead of replacing mark attached to inode which is a more complex operation. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Provide helper for dropping mark's chunk referenceJan Kara
Provide a helper function audit_mark_put_chunk() for dropping mark's reference (which has to happen only after RCU grace period expires). Currently that happens only from a single place but in later patches we introduce more callers. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Remove pointless check in insert_hash()Jan Kara
The audit_tree_group->mark_mutex is held all the time while we create the fsnotify mark, add it to the inode, and insert chunk into the hash. Hence mark cannot get detached during this time and so the check whether the mark is attached in insert_hash() is pointless. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Factor out chunk replacement codeJan Kara
Chunk replacement code is very similar for the cases where we grow or shrink chunk. Factor the code out into a common helper function. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Make hash table insertion safe against concurrent lookupsJan Kara
Currently, the audit tree code does not make sure that when a chunk is inserted into the hash table, it is fully initialized. So in theory a user of RCU lookup could see uninitialized structure in the hash table and crash. Add appropriate barriers between initialization of the structure and its insertion into hash table. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Embed key into chunkJan Kara
Currently chunk hash key (which is in fact pointer to the inode) is derived as chunk->mark.conn->obj. It is tricky to make this dereference reliable for hash table lookups only under RCU as mark can get detached from the connector and connector gets freed independently of the running lookup. Thus there is a possible use after free / NULL ptr dereference issue: CPU1 CPU2 untag_chunk() ... audit_tree_lookup() list_for_each_entry_rcu(p, list, hash) { list_del_rcu(&chunk->hash); fsnotify_destroy_mark(entry); fsnotify_put_mark(entry) chunk_to_key(p) if (!chunk->mark.connector) ... hlist_del_init_rcu(&mark->obj_list); if (hlist_empty(&conn->list)) { inode = fsnotify_detach_connector_from_object(conn); mark->connector = NULL; ... frees connector from workqueue chunk->mark.connector->obj This race is probably impossible to hit in practice as the race window on CPU1 is very narrow and CPU2 has a lot of code to execute. Still it's better to have this fixed. Since the inode the chunk is attached to is constant during chunk's lifetime it is easy to cache the key in the chunk itself and thus avoid these issues. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Fix possible tagging failuresJan Kara
Audit tree code is replacing marks attached to inodes in non-atomic way. Thus fsnotify_find_mark() in tag_chunk() may find a mark that belongs to a chunk that is no longer valid one and will soon be destroyed. Tags added to such chunk will be simply lost. Fix the problem by making sure old mark is marked as going away (through fsnotify_detach_mark()) before dropping mark_mutex and thus in an atomic way wrt tag_chunk(). Note that this does not fix the problem completely as if tag_chunk() finds a mark that is going away, it fails with -ENOENT. But at least the failure is not silent and currently there's no way to search for another fsnotify mark attached to the inode. We'll fix this problem in later patch. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit: Fix possible spurious -ENOSPC errorJan Kara
When an inode is tagged with a tree, tag_chunk() checks whether there is audit_tree_group mark attached to the inode and adds one if not. However nothing protects another tag_chunk() to add the mark between we've checked and try to add the fsnotify mark thus resulting in an error from fsnotify_add_mark() and consequently an ENOSPC error from tag_chunk(). Fix the problem by holding mark_mutex over the whole check-insert code sequence. Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-12audit_tree: Remove mark->lock lockingJan Kara
Currently, audit_tree code uses mark->lock to protect against detaching of mark from an inode. In most places it however also uses mark->group->mark_mutex (as we need to atomically replace attached marks) and this provides protection against mark detaching as well. So just remove protection with mark->lock from audit tree code and replace it with mark->group->mark_mutex protection in all the places. It simplifies the code and gets rid of some ugly catches like calling fsnotify_add_mark_locked() with mark->lock held (which cannot sleep only because we hold a reference to another mark attached to the same inode). Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-08-17Merge tag 'fsnotify_for_v4.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: "fsnotify cleanups from Amir and a small inotify improvement" * tag 'fsnotify_for_v4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: inotify: Add flag IN_MASK_CREATE for inotify_add_watch() fanotify: factor out helpers to add/remove mark fsnotify: add helper to get mask from connector fsnotify: let connector point to an abstract object fsnotify: pass connp and object type to fsnotify_add_mark() fsnotify: use typedef fsnotify_connp_t for brevity
2018-06-28audit: check audit_enabled in audit_tree_log_remove_rule()Richard Guy Briggs
Respect the audit_enabled flag when printing tree rule config change records. See: https://github.com/linux-audit/audit-kernel/issues/50 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: tweak the subject line] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-06-27fsnotify: let connector point to an abstract objectAmir Goldstein
Make the code to attach/detach a connector to object more generic by letting the fsnotify connector point to an abstract fsnotify_connp_t. Code that needs to dereference an inode or mount object now uses the helpers fsnotify_conn_{inode,mount}. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-05-18fsnotify: add fsnotify_add_inode_mark() wrappersAmir Goldstein
Before changing the arguments of the functions fsnotify_add_mark() and fsnotify_add_mark_locked(), convert most callers to use a wrapper. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-05-18fsnotify: remove redundant arguments to handle_event()Amir Goldstein
inode_mark and vfsmount_mark arguments are passed to handle_event() operation as function arguments as well as on iter_info struct. The difference is that iter_info struct may contain marks that should not be handled and are represented as NULL arguments to inode_mark or vfsmount_mark. Instead of passing the inode_mark and vfsmount_mark arguments, add a report_mask member to iter_info struct to indicate which marks should be handled, versus marks that should only be kept alive during user wait. This change is going to be used for passing more mark types with handle_event() (i.e. super block marks). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2018-02-23audit: track the owner of the command mutex ourselvesPaul Moore
Evidently the __mutex_owner() function was never intended for use outside the core mutex code, so build a thing locking wrapper around the mutex code which allows us to track the mutex owner. One, arguably positive, side effect is that this allows us to hide the audit_cmd_mutex inside of kernel/audit.c behind the lock/unlock functions. Reported-by: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-11-14Merge branch 'fsnotify' of ↵Linus Torvalds
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-Hartman
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>
2017-10-31fsnotify: convert fsnotify_mark.refcnt from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable fsnotify_mark.refcnt is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-05-03Merge branch 'fsnotify' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: "The branch contains mainly a rework of fsnotify infrastructure fixing a shortcoming that we have waited for response to fanotify permission events with SRCU read lock held and when the process consuming events was slow to respond the kernel has stalled. It also contains several cleanups of unnecessary indirections in fsnotify framework and a bugfix from Amir fixing leakage of kernel internal errno to userspace" * 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (37 commits) fanotify: don't expose EOPENSTALE to userspace fsnotify: remove a stray unlock fsnotify: Move ->free_mark callback to fsnotify_ops fsnotify: Add group pointer in fsnotify_init_mark() fsnotify: Drop inode_mark.c fsnotify: Remove fsnotify_find_{inode|vfsmount}_mark() fsnotify: Remove fsnotify_detach_group_marks() fsnotify: Rename fsnotify_clear_marks_by_group_flags() fsnotify: Inline fsnotify_clear_{inode|vfsmount}_mark_group() fsnotify: Remove fsnotify_recalc_{inode|vfsmount}_mask() fsnotify: Remove fsnotify_set_mark_{,ignored_}mask_locked() fanotify: Release SRCU lock when waiting for userspace response fsnotify: Pass fsnotify_iter_info into handle_event handler fsnotify: Provide framework for dropping SRCU lock in ->handle_event fsnotify: Remove special handling of mark destruction on group shutdown fsnotify: Detach mark from object list when last reference is dropped fsnotify: Move queueing of mark for destruction into fsnotify_put_mark() inotify: Do not drop mark reference under idr_lock fsnotify: Free fsnotify_mark_connector when there is no mark attached fsnotify: Lock object list with connector lock ...
2017-05-02audit: convert audit_tree.count from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> [PM: fix subject line, add #include] Signed-off-by: Paul Moore <paul@paul-moore.com>
2017-04-10fsnotify: Move ->free_mark callback to fsnotify_opsJan Kara
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 Kara
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 Kara
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: Pass fsnotify_iter_info into handle_event handlerJan Kara
Pass fsnotify_iter_info into ->handle_event() handler so that it can release and reacquire SRCU lock via fsnotify_prepare_user_wait() and fsnotify_finish_user_wait() functions. These functions also make sure current marks are appropriately pinned so that iteration protected by srcu in fsnotify() stays safe. 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: Detach mark from object list when last reference is droppedJan Kara
Instead of removing mark from object list from fsnotify_detach_mark(), remove the mark when last reference to the mark is dropped. This will allow fanotify to wait for userspace response to event without having to hold onto fsnotify_mark_srcu. To avoid pinning inodes by elevated refcount (and thus e.g. delaying file deletion) while someone holds mark reference, we detach connector from the object also from fsnotify_destroy_marks() and not only after removing last mark from the list as it was 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: Move object pointer to fsnotify_mark_connectorJan Kara
Move pointer to inode / vfsmount from mark itself to the fsnotify_mark_connector structure. This is another step on the path towards decoupling inode / vfsmount lifetime from notification mark lifetime. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-10audit_tree: Use mark flags to check whether mark is aliveJan Kara
Currently audit code uses checking of mark->inode to verify whether mark is still alive. Switch that to checking mark flags as that is more logical and current way will become unreliable in future. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-04-05audit: Abstract hash key handlingJan Kara
Audit tree currently uses inode pointer as a key into the hash table. Getting that from notification mark will be somewhat more difficult with coming fsnotify changes. So abstract getting of hash key from the audit chunk and inode so that we can change the method to obtain a key easily. Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> CC: Paul Moore <paul@paul-moore.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Jan Kara <jack@suse.cz>
2017-01-05Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/auditLinus Torvalds
Pull audit fixes from Paul Moore: "Two small fixes relating to audit's use of fsnotify. The first patch plugs a leak and the second fixes some lock shenanigans. The patches are small and I banged on this for an afternoon with our testsuite and didn't see anything odd" * 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit: audit: Fix sleep in atomic fsnotify: Remove fsnotify_duplicate_mark()