diff options
author | Linus Torvalds | 2022-08-01 08:50:39 -0700 |
---|---|---|
committer | Linus Torvalds | 2022-08-01 08:50:39 -0700 |
commit | bec14d79f73e7bc2530e73b7c7ee0484029ea0ea (patch) | |
tree | 0dca84d7f9297e2522fa6670e6e0811c7fa142e6 | |
parent | af07685b9ca18a5104c073847c83cf443f5c6114 (diff) | |
parent | feee1ce45a5666bbdb08c5bb2f5f394047b1915b (diff) |
Merge tag 'fsnotify_for_v5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
- support for FAN_MARK_IGNORE which untangles some of the not well
defined corner cases with fanotify ignore masks
- small cleanups
* tag 'fsnotify_for_v5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: Fix comment typo
fanotify: introduce FAN_MARK_IGNORE
fanotify: cleanups for fanotify_mark() input validations
fanotify: prepare for setting event flags in ignore mask
fs: inotify: Fix typo in inotify comment
-rw-r--r-- | fs/notify/fanotify/fanotify.c | 19 | ||||
-rw-r--r-- | fs/notify/fanotify/fanotify.h | 2 | ||||
-rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 110 | ||||
-rw-r--r-- | fs/notify/fdinfo.c | 6 | ||||
-rw-r--r-- | fs/notify/fsnotify.c | 23 | ||||
-rw-r--r-- | fs/notify/inotify/inotify_user.c | 2 | ||||
-rw-r--r-- | include/linux/fanotify.h | 14 | ||||
-rw-r--r-- | include/linux/fsnotify_backend.h | 89 | ||||
-rw-r--r-- | include/uapi/linux/fanotify.h | 8 |
9 files changed, 214 insertions, 59 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 4f897e109547..cd7d09a569ff 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -295,12 +295,13 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, const void *data, int data_type, struct inode *dir) { - __u32 marks_mask = 0, marks_ignored_mask = 0; + __u32 marks_mask = 0, marks_ignore_mask = 0; __u32 test_mask, user_mask = FANOTIFY_OUTGOING_EVENTS | FANOTIFY_EVENT_FLAGS; const struct path *path = fsnotify_data_path(data, data_type); unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS); struct fsnotify_mark *mark; + bool ondir = event_mask & FAN_ONDIR; int type; pr_debug("%s: report_mask=%x mask=%x data=%p data_type=%d\n", @@ -315,19 +316,21 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, return 0; } else if (!(fid_mode & FAN_REPORT_FID)) { /* Do we have a directory inode to report? */ - if (!dir && !(event_mask & FS_ISDIR)) + if (!dir && !ondir) return 0; } fsnotify_foreach_iter_mark_type(iter_info, mark, type) { - /* Apply ignore mask regardless of mark's ISDIR flag */ - marks_ignored_mask |= mark->ignored_mask; + /* + * Apply ignore mask depending on event flags in ignore mask. + */ + marks_ignore_mask |= + fsnotify_effective_ignore_mask(mark, ondir, type); /* - * If the event is on dir and this mark doesn't care about - * events on dir, don't send it! + * Send the event depending on event flags in mark mask. */ - if (event_mask & FS_ISDIR && !(mark->mask & FS_ISDIR)) + if (!fsnotify_mask_applicable(mark->mask, ondir, type)) continue; marks_mask |= mark->mask; @@ -336,7 +339,7 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, *match_mask |= 1U << type; } - test_mask = event_mask & marks_mask & ~marks_ignored_mask; + test_mask = event_mask & marks_mask & ~marks_ignore_mask; /* * For dirent modification events (create/delete/move) that do not carry diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 80e0ec95b113..1d9f11255c64 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -499,6 +499,8 @@ static inline unsigned int fanotify_mark_user_flags(struct fsnotify_mark *mark) mflags |= FAN_MARK_IGNORED_SURV_MODIFY; if (mark->flags & FSNOTIFY_MARK_FLAG_NO_IREF) mflags |= FAN_MARK_EVICTABLE; + if (mark->flags & FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS) + mflags |= FAN_MARK_IGNORE; return mflags; } diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index b08ce0d821a7..f0e49a406ffa 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1009,10 +1009,10 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, mask &= ~umask; spin_lock(&fsn_mark->lock); oldmask = fsnotify_calc_mask(fsn_mark); - if (!(flags & FAN_MARK_IGNORED_MASK)) { + if (!(flags & FANOTIFY_MARK_IGNORE_BITS)) { fsn_mark->mask &= ~mask; } else { - fsn_mark->ignored_mask &= ~mask; + fsn_mark->ignore_mask &= ~mask; } newmask = fsnotify_calc_mask(fsn_mark); /* @@ -1021,7 +1021,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, * changes to the mask. * Destroy mark when only umask bits remain. */ - *destroy = !((fsn_mark->mask | fsn_mark->ignored_mask) & ~umask); + *destroy = !((fsn_mark->mask | fsn_mark->ignore_mask) & ~umask); spin_unlock(&fsn_mark->lock); return oldmask & ~newmask; @@ -1085,15 +1085,24 @@ static bool fanotify_mark_update_flags(struct fsnotify_mark *fsn_mark, unsigned int fan_flags) { bool want_iref = !(fan_flags & FAN_MARK_EVICTABLE); + unsigned int ignore = fan_flags & FANOTIFY_MARK_IGNORE_BITS; bool recalc = false; /* + * When using FAN_MARK_IGNORE for the first time, mark starts using + * independent event flags in ignore mask. After that, trying to + * update the ignore mask with the old FAN_MARK_IGNORED_MASK API + * will result in EEXIST error. + */ + if (ignore == FAN_MARK_IGNORE) + fsn_mark->flags |= FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS; + + /* * Setting FAN_MARK_IGNORED_SURV_MODIFY for the first time may lead to * the removal of the FS_MODIFY bit in calculated mask if it was set - * because of an ignored mask that is now going to survive FS_MODIFY. + * because of an ignore mask that is now going to survive FS_MODIFY. */ - if ((fan_flags & FAN_MARK_IGNORED_MASK) && - (fan_flags & FAN_MARK_IGNORED_SURV_MODIFY) && + if (ignore && (fan_flags & FAN_MARK_IGNORED_SURV_MODIFY) && !(fsn_mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)) { fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY; if (!(fsn_mark->mask & FS_MODIFY)) @@ -1120,10 +1129,10 @@ static bool fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, bool recalc; spin_lock(&fsn_mark->lock); - if (!(fan_flags & FAN_MARK_IGNORED_MASK)) + if (!(fan_flags & FANOTIFY_MARK_IGNORE_BITS)) fsn_mark->mask |= mask; else - fsn_mark->ignored_mask |= mask; + fsn_mark->ignore_mask |= mask; recalc = fsnotify_calc_mask(fsn_mark) & ~fsnotify_conn_mask(fsn_mark->connector); @@ -1187,6 +1196,37 @@ static int fanotify_group_init_error_pool(struct fsnotify_group *group) sizeof(struct fanotify_error_event)); } +static int fanotify_may_update_existing_mark(struct fsnotify_mark *fsn_mark, + unsigned int fan_flags) +{ + /* + * Non evictable mark cannot be downgraded to evictable mark. + */ + if (fan_flags & FAN_MARK_EVICTABLE && + !(fsn_mark->flags & FSNOTIFY_MARK_FLAG_NO_IREF)) + return -EEXIST; + + /* + * New ignore mask semantics cannot be downgraded to old semantics. + */ + if (fan_flags & FAN_MARK_IGNORED_MASK && + fsn_mark->flags & FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS) + return -EEXIST; + + /* + * An ignore mask that survives modify could never be downgraded to not + * survive modify. With new FAN_MARK_IGNORE semantics we make that rule + * explicit and return an error when trying to update the ignore mask + * without the original FAN_MARK_IGNORED_SURV_MODIFY value. + */ + if (fan_flags & FAN_MARK_IGNORE && + !(fan_flags & FAN_MARK_IGNORED_SURV_MODIFY) && + fsn_mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY) + return -EEXIST; + + return 0; +} + static int fanotify_add_mark(struct fsnotify_group *group, fsnotify_connp_t *connp, unsigned int obj_type, __u32 mask, unsigned int fan_flags, @@ -1208,19 +1248,18 @@ static int fanotify_add_mark(struct fsnotify_group *group, } /* - * Non evictable mark cannot be downgraded to evictable mark. + * Check if requested mark flags conflict with an existing mark flags. */ - if (fan_flags & FAN_MARK_EVICTABLE && - !(fsn_mark->flags & FSNOTIFY_MARK_FLAG_NO_IREF)) { - ret = -EEXIST; + ret = fanotify_may_update_existing_mark(fsn_mark, fan_flags); + if (ret) goto out; - } /* * Error events are pre-allocated per group, only if strictly * needed (i.e. FAN_FS_ERROR was requested). */ - if (!(fan_flags & FAN_MARK_IGNORED_MASK) && (mask & FAN_FS_ERROR)) { + if (!(fan_flags & FANOTIFY_MARK_IGNORE_BITS) && + (mask & FAN_FS_ERROR)) { ret = fanotify_group_init_error_pool(group); if (ret) goto out; @@ -1261,10 +1300,10 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, /* * If some other task has this inode open for write we should not add - * an ignored mark, unless that ignored mark is supposed to survive + * an ignore mask, unless that ignore mask is supposed to survive * modification changes anyway. */ - if ((flags & FAN_MARK_IGNORED_MASK) && + if ((flags & FANOTIFY_MARK_IGNORE_BITS) && !(flags & FAN_MARK_IGNORED_SURV_MODIFY) && inode_is_open_for_write(inode)) return 0; @@ -1520,7 +1559,8 @@ static int fanotify_events_supported(struct fsnotify_group *group, unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; /* Strict validation of events in non-dir inode mask with v5.17+ APIs */ bool strict_dir_events = FAN_GROUP_FLAG(group, FAN_REPORT_TARGET_FID) || - (mask & FAN_RENAME); + (mask & FAN_RENAME) || + (flags & FAN_MARK_IGNORE); /* * Some filesystems such as 'proc' acquire unusual locks when opening @@ -1557,7 +1597,8 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, __kernel_fsid_t __fsid, *fsid = NULL; u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS; unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; - bool ignored = flags & FAN_MARK_IGNORED_MASK; + unsigned int mark_cmd = flags & FANOTIFY_MARK_CMD_BITS; + unsigned int ignore = flags & FANOTIFY_MARK_IGNORE_BITS; unsigned int obj_type, fid_mode; u32 umask = 0; int ret; @@ -1586,7 +1627,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, return -EINVAL; } - switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) { + switch (mark_cmd) { case FAN_MARK_ADD: case FAN_MARK_REMOVE: if (!mask) @@ -1606,9 +1647,19 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, if (mask & ~valid_mask) return -EINVAL; - /* Event flags (ONDIR, ON_CHILD) are meaningless in ignored mask */ - if (ignored) + + /* We don't allow FAN_MARK_IGNORE & FAN_MARK_IGNORED_MASK together */ + if (ignore == (FAN_MARK_IGNORE | FAN_MARK_IGNORED_MASK)) + return -EINVAL; + + /* + * Event flags (FAN_ONDIR, FAN_EVENT_ON_CHILD) have no effect with + * FAN_MARK_IGNORED_MASK. + */ + if (ignore == FAN_MARK_IGNORED_MASK) { mask &= ~FANOTIFY_EVENT_FLAGS; + umask = FANOTIFY_EVENT_FLAGS; + } f = fdget(fanotify_fd); if (unlikely(!f.file)) @@ -1672,7 +1723,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, if (mask & FAN_RENAME && !(fid_mode & FAN_REPORT_NAME)) goto fput_and_out; - if (flags & FAN_MARK_FLUSH) { + if (mark_cmd == FAN_MARK_FLUSH) { ret = 0; if (mark_type == FAN_MARK_MOUNT) fsnotify_clear_vfsmount_marks_by_group(group); @@ -1688,7 +1739,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, if (ret) goto fput_and_out; - if (flags & FAN_MARK_ADD) { + if (mark_cmd == FAN_MARK_ADD) { ret = fanotify_events_supported(group, &path, mask, flags); if (ret) goto path_put_and_out; @@ -1712,6 +1763,13 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, else mnt = path.mnt; + ret = mnt ? -EINVAL : -EISDIR; + /* FAN_MARK_IGNORE requires SURV_MODIFY for sb/mount/dir marks */ + if (mark_cmd == FAN_MARK_ADD && ignore == FAN_MARK_IGNORE && + (mnt || S_ISDIR(inode->i_mode)) && + !(flags & FAN_MARK_IGNORED_SURV_MODIFY)) + goto path_put_and_out; + /* Mask out FAN_EVENT_ON_CHILD flag for sb/mount/non-dir marks */ if (mnt || !S_ISDIR(inode->i_mode)) { mask &= ~FAN_EVENT_ON_CHILD; @@ -1721,12 +1779,12 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, * events with parent/name info for non-directory. */ if ((fid_mode & FAN_REPORT_DIR_FID) && - (flags & FAN_MARK_ADD) && !ignored) + (flags & FAN_MARK_ADD) && !ignore) mask |= FAN_EVENT_ON_CHILD; } /* create/update an inode mark */ - switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) { + switch (mark_cmd) { case FAN_MARK_ADD: if (mark_type == FAN_MARK_MOUNT) ret = fanotify_add_vfsmount_mark(group, mnt, mask, @@ -1804,7 +1862,7 @@ static int __init fanotify_user_setup(void) BUILD_BUG_ON(FANOTIFY_INIT_FLAGS & FANOTIFY_INTERNAL_GROUP_FLAGS); BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 12); - BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 10); + BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 11); fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, SLAB_PANIC|SLAB_ACCOUNT); diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c index 59fb40abe33d..55081ae3a6ec 100644 --- a/fs/notify/fdinfo.c +++ b/fs/notify/fdinfo.c @@ -113,7 +113,7 @@ static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark) return; seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ", inode->i_ino, inode->i_sb->s_dev, - mflags, mark->mask, mark->ignored_mask); + mflags, mark->mask, mark->ignore_mask); show_mark_fhandle(m, inode); seq_putc(m, '\n'); iput(inode); @@ -121,12 +121,12 @@ static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark) struct mount *mnt = fsnotify_conn_mount(mark->connector); seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n", - mnt->mnt_id, mflags, mark->mask, mark->ignored_mask); + mnt->mnt_id, mflags, mark->mask, mark->ignore_mask); } else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_SB) { struct super_block *sb = fsnotify_conn_sb(mark->connector); seq_printf(m, "fanotify sdev:%x mflags:%x mask:%x ignored_mask:%x\n", - sb->s_dev, mflags, mark->mask, mark->ignored_mask); + sb->s_dev, mflags, mark->mask, mark->ignore_mask); } } diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index 0b3e74935cb4..7974e91ffe13 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -100,7 +100,7 @@ void fsnotify_sb_delete(struct super_block *sb) * Given an inode, first check if we care what happens to our children. Inotify * and dnotify both tell their parents about events. If we care about any event * on a child we run all of our children and set a dentry flag saying that the - * parent cares. Thus when an event happens on a child it can quickly tell if + * parent cares. Thus when an event happens on a child it can quickly tell * if there is a need to find a parent and send the event to the parent. */ void __fsnotify_update_child_dentry_flags(struct inode *inode) @@ -324,7 +324,8 @@ static int send_to_group(__u32 mask, const void *data, int data_type, struct fsnotify_group *group = NULL; __u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS); __u32 marks_mask = 0; - __u32 marks_ignored_mask = 0; + __u32 marks_ignore_mask = 0; + bool is_dir = mask & FS_ISDIR; struct fsnotify_mark *mark; int type; @@ -336,7 +337,7 @@ static int send_to_group(__u32 mask, const void *data, int data_type, fsnotify_foreach_iter_mark_type(iter_info, mark, type) { if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)) - mark->ignored_mask = 0; + mark->ignore_mask = 0; } } @@ -344,14 +345,15 @@ static int send_to_group(__u32 mask, const void *data, int data_type, fsnotify_foreach_iter_mark_type(iter_info, mark, type) { group = mark->group; marks_mask |= mark->mask; - marks_ignored_mask |= mark->ignored_mask; + marks_ignore_mask |= + fsnotify_effective_ignore_mask(mark, is_dir, type); } - pr_debug("%s: group=%p mask=%x marks_mask=%x marks_ignored_mask=%x data=%p data_type=%d dir=%p cookie=%d\n", - __func__, group, mask, marks_mask, marks_ignored_mask, + pr_debug("%s: group=%p mask=%x marks_mask=%x marks_ignore_mask=%x data=%p data_type=%d dir=%p cookie=%d\n", + __func__, group, mask, marks_mask, marks_ignore_mask, data, data_type, dir, cookie); - if (!(test_mask & marks_mask & ~marks_ignored_mask)) + if (!(test_mask & marks_mask & ~marks_ignore_mask)) return 0; if (group->ops->handle_event) { @@ -423,7 +425,8 @@ static bool fsnotify_iter_select_report_types( * But is *this mark* watching children? */ if (type == FSNOTIFY_ITER_TYPE_PARENT && - !(mark->mask & FS_EVENT_ON_CHILD)) + !(mark->mask & FS_EVENT_ON_CHILD) && + !(fsnotify_ignore_mask(mark) & FS_EVENT_ON_CHILD)) continue; fsnotify_iter_set_report_type(iter_info, type); @@ -532,8 +535,8 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir, /* - * If this is a modify event we may need to clear some ignored masks. - * In that case, the object with ignored masks will have the FS_MODIFY + * If this is a modify event we may need to clear some ignore masks. + * In that case, the object with ignore masks will have the FS_MODIFY * event in its mask. * Otherwise, return if none of the marks care about this type of event. */ diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index ed42a189faa2..1c4bfdab008d 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -136,7 +136,7 @@ static inline u32 inotify_mask_to_arg(__u32 mask) IN_Q_OVERFLOW); } -/* intofiy userspace file descriptor functions */ +/* inotify userspace file descriptor functions */ static __poll_t inotify_poll(struct file *file, poll_table *wait) { struct fsnotify_group *group = file->private_data; diff --git a/include/linux/fanotify.h b/include/linux/fanotify.h index e517dbcf74ed..8ad743def6f3 100644 --- a/include/linux/fanotify.h +++ b/include/linux/fanotify.h @@ -59,15 +59,19 @@ #define FANOTIFY_MARK_TYPE_BITS (FAN_MARK_INODE | FAN_MARK_MOUNT | \ FAN_MARK_FILESYSTEM) +#define FANOTIFY_MARK_CMD_BITS (FAN_MARK_ADD | FAN_MARK_REMOVE | \ + FAN_MARK_FLUSH) + +#define FANOTIFY_MARK_IGNORE_BITS (FAN_MARK_IGNORED_MASK | \ + FAN_MARK_IGNORE) + #define FANOTIFY_MARK_FLAGS (FANOTIFY_MARK_TYPE_BITS | \ - FAN_MARK_ADD | \ - FAN_MARK_REMOVE | \ + FANOTIFY_MARK_CMD_BITS | \ + FANOTIFY_MARK_IGNORE_BITS | \ FAN_MARK_DONT_FOLLOW | \ FAN_MARK_ONLYDIR | \ - FAN_MARK_IGNORED_MASK | \ FAN_MARK_IGNORED_SURV_MODIFY | \ - FAN_MARK_EVICTABLE | \ - FAN_MARK_FLUSH) + FAN_MARK_EVICTABLE) /* * Events that can be reported with data type FSNOTIFY_EVENT_PATH. diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index 9560734759fa..d7d96c806bff 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -518,8 +518,8 @@ struct fsnotify_mark { struct hlist_node obj_list; /* Head of list of marks for an object [mark ref] */ struct fsnotify_mark_connector *connector; - /* Events types to ignore [mark->lock, group->mark_mutex] */ - __u32 ignored_mask; + /* Events types and flags to ignore [mark->lock, group->mark_mutex] */ + __u32 ignore_mask; /* General fsnotify mark flags */ #define FSNOTIFY_MARK_FLAG_ALIVE 0x0001 #define FSNOTIFY_MARK_FLAG_ATTACHED 0x0002 @@ -529,6 +529,7 @@ struct fsnotify_mark { /* fanotify mark flags */ #define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x0100 #define FSNOTIFY_MARK_FLAG_NO_IREF 0x0200 +#define FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS 0x0400 unsigned int flags; /* flags [mark->lock] */ }; @@ -655,15 +656,91 @@ extern void fsnotify_remove_queued_event(struct fsnotify_group *group, /* functions used to manipulate the marks attached to inodes */ -/* Get mask for calculating object interest taking ignored mask into account */ +/* + * Canonical "ignore mask" including event flags. + * + * Note the subtle semantic difference from the legacy ->ignored_mask. + * ->ignored_mask traditionally only meant which events should be ignored, + * while ->ignore_mask also includes flags regarding the type of objects on + * which events should be ignored. + */ +static inline __u32 fsnotify_ignore_mask(struct fsnotify_mark *mark) +{ + __u32 ignore_mask = mark->ignore_mask; + + /* The event flags in ignore mask take effect */ + if (mark->flags & FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS) + return ignore_mask; + + /* + * Legacy behavior: + * - Always ignore events on dir + * - Ignore events on child if parent is watching children + */ + ignore_mask |= FS_ISDIR; + ignore_mask &= ~FS_EVENT_ON_CHILD; + ignore_mask |= mark->mask & FS_EVENT_ON_CHILD; + + return ignore_mask; +} + +/* Legacy ignored_mask - only event types to ignore */ +static inline __u32 fsnotify_ignored_events(struct fsnotify_mark *mark) +{ + return mark->ignore_mask & ALL_FSNOTIFY_EVENTS; +} + +/* + * Check if mask (or ignore mask) should be applied depending if victim is a + * directory and whether it is reported to a watching parent. + */ +static inline bool fsnotify_mask_applicable(__u32 mask, bool is_dir, + int iter_type) +{ + /* Should mask be applied to a directory? */ + if (is_dir && !(mask & FS_ISDIR)) + return false; + + /* Should mask be applied to a child? */ + if (iter_type == FSNOTIFY_ITER_TYPE_PARENT && + !(mask & FS_EVENT_ON_CHILD)) + return false; + + return true; +} + +/* + * Effective ignore mask taking into account if event victim is a + * directory and whether it is reported to a watching parent. + */ +static inline __u32 fsnotify_effective_ignore_mask(struct fsnotify_mark *mark, + bool is_dir, int iter_type) +{ + __u32 ignore_mask = fsnotify_ignored_events(mark); + + if (!ignore_mask) + return 0; + + /* For non-dir and non-child, no need to consult the event flags */ + if (!is_dir && iter_type != FSNOTIFY_ITER_TYPE_PARENT) + return ignore_mask; + + ignore_mask = fsnotify_ignore_mask(mark); + if (!fsnotify_mask_applicable(ignore_mask, is_dir, iter_type)) + return 0; + + return ignore_mask & ALL_FSNOTIFY_EVENTS; +} + +/* Get mask for calculating object interest taking ignore mask into account */ static inline __u32 fsnotify_calc_mask(struct fsnotify_mark *mark) { __u32 mask = mark->mask; - if (!mark->ignored_mask) + if (!fsnotify_ignored_events(mark)) return mask; - /* Interest in FS_MODIFY may be needed for clearing ignored mask */ + /* Interest in FS_MODIFY may be needed for clearing ignore mask */ if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)) mask |= FS_MODIFY; @@ -671,7 +748,7 @@ static inline __u32 fsnotify_calc_mask(struct fsnotify_mark *mark) * If mark is interested in ignoring events on children, the object must * show interest in those events for fsnotify_parent() to notice it. */ - return mask | (mark->ignored_mask & ALL_FSNOTIFY_EVENTS); + return mask | mark->ignore_mask; } /* Get mask of events for a list of marks */ diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index f1f89132d60e..d8536d77fea1 100644 --- a/include/uapi/linux/fanotify.h +++ b/include/uapi/linux/fanotify.h @@ -83,12 +83,20 @@ #define FAN_MARK_FLUSH 0x00000080 /* FAN_MARK_FILESYSTEM is 0x00000100 */ #define FAN_MARK_EVICTABLE 0x00000200 +/* This bit is mutually exclusive with FAN_MARK_IGNORED_MASK bit */ +#define FAN_MARK_IGNORE 0x00000400 /* These are NOT bitwise flags. Both bits can be used togther. */ #define FAN_MARK_INODE 0x00000000 #define FAN_MARK_MOUNT 0x00000010 #define FAN_MARK_FILESYSTEM 0x00000100 +/* + * Convenience macro - FAN_MARK_IGNORE requires FAN_MARK_IGNORED_SURV_MODIFY + * for non-inode mark types. + */ +#define FAN_MARK_IGNORE_SURV (FAN_MARK_IGNORE | FAN_MARK_IGNORED_SURV_MODIFY) + /* Deprecated - do not use this in programs and do not add new flags here! */ #define FAN_ALL_MARK_FLAGS (FAN_MARK_ADD |\ FAN_MARK_REMOVE |\ |