diff options
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 34 | ||||
| -rw-r--r-- | include/linux/fanotify.h | 4 |
2 files changed, 23 insertions, 15 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index c2255b440df9..b08ce0d821a7 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1513,8 +1513,15 @@ static int fanotify_test_fid(struct dentry *dentry) return 0; } -static int fanotify_events_supported(struct path *path, __u64 mask) +static int fanotify_events_supported(struct fsnotify_group *group, + struct path *path, __u64 mask, + unsigned int flags) { + 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); + /* * Some filesystems such as 'proc' acquire unusual locks when opening * files. For them fanotify permission events have high chances of @@ -1526,6 +1533,16 @@ static int fanotify_events_supported(struct path *path, __u64 mask) if (mask & FANOTIFY_PERM_EVENTS && path->mnt->mnt_sb->s_type->fs_flags & FS_DISALLOW_NOTIFY_PERM) return -EINVAL; + + /* + * We shouldn't have allowed setting dirent events and the directory + * flags FAN_ONDIR and FAN_EVENT_ON_CHILD in mask of non-dir inode, + * but because we always allowed it, error only when using new APIs. + */ + if (strict_dir_events && mark_type == FAN_MARK_INODE && + !d_is_dir(path->dentry) && (mask & FANOTIFY_DIRONLY_EVENT_BITS)) + return -ENOTDIR; + return 0; } @@ -1672,7 +1689,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, goto fput_and_out; if (flags & FAN_MARK_ADD) { - ret = fanotify_events_supported(&path, mask); + ret = fanotify_events_supported(group, &path, mask, flags); if (ret) goto path_put_and_out; } @@ -1695,19 +1712,6 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, else mnt = path.mnt; - /* - * FAN_RENAME is not allowed on non-dir (for now). - * We shouldn't have allowed setting any dirent events in mask of - * non-dir, but because we always allowed it, error only if group - * was initialized with the new flag FAN_REPORT_TARGET_FID. - */ - ret = -ENOTDIR; - if (inode && !S_ISDIR(inode->i_mode) && - ((mask & FAN_RENAME) || - ((mask & FANOTIFY_DIRENT_EVENTS) && - FAN_GROUP_FLAG(group, FAN_REPORT_TARGET_FID)))) - 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; diff --git a/include/linux/fanotify.h b/include/linux/fanotify.h index edc28555814c..e517dbcf74ed 100644 --- a/include/linux/fanotify.h +++ b/include/linux/fanotify.h @@ -111,6 +111,10 @@ FANOTIFY_PERM_EVENTS | \ FAN_Q_OVERFLOW | FAN_ONDIR) +/* Events and flags relevant only for directories */ +#define FANOTIFY_DIRONLY_EVENT_BITS (FANOTIFY_DIRENT_EVENTS | \ + FAN_EVENT_ON_CHILD | FAN_ONDIR) + #define ALL_FANOTIFY_EVENT_BITS (FANOTIFY_OUTGOING_EVENTS | \ FANOTIFY_EVENT_FLAGS) |