diff options
| -rw-r--r-- | fs/notify/fsnotify.c | 47 | ||||
| -rw-r--r-- | include/linux/fsnotify.h | 19 | ||||
| -rw-r--r-- | include/linux/fsnotify_backend.h | 15 | ||||
| -rw-r--r-- | include/linux/security.h | 1 | ||||
| -rw-r--r-- | security/security.c | 16 |
5 files changed, 68 insertions, 30 deletions
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index c5adf833bf6..66826862789 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -169,27 +169,22 @@ void __fsnotify_flush_ignored_mask(struct inode *inode, void *data, int data_is) } } -static void send_to_group(struct fsnotify_group *group, struct inode *to_tell, - struct vfsmount *mnt, __u32 mask, void *data, - int data_is, u32 cookie, const unsigned char *file_name, - struct fsnotify_event **event) +static int send_to_group(struct fsnotify_group *group, struct inode *to_tell, + struct vfsmount *mnt, __u32 mask, void *data, + int data_is, u32 cookie, const unsigned char *file_name, + struct fsnotify_event **event) { if (!group->ops->should_send_event(group, to_tell, mnt, mask, data, data_is)) - return; + return 0; if (!*event) { *event = fsnotify_create_event(to_tell, mask, data, data_is, file_name, cookie, GFP_KERNEL); - /* - * shit, we OOM'd and now we can't tell, maybe - * someday someone else will want to do something - * here - */ if (!*event) - return; + return -ENOMEM; } - group->ops->handle_event(group, *event); + return group->ops->handle_event(group, *event); } static bool needed_by_vfsmount(__u32 test_mask, struct vfsmount *mnt) @@ -206,20 +201,20 @@ static bool needed_by_vfsmount(__u32 test_mask, struct vfsmount *mnt) * out to all of the registered fsnotify_group. Those groups can then use the * notification event in whatever means they feel necessary. */ -void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, - const unsigned char *file_name, u32 cookie) +int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, + const unsigned char *file_name, u32 cookie) { struct fsnotify_group *group; struct fsnotify_event *event = NULL; struct vfsmount *mnt = NULL; - int idx; + int idx, ret = 0; /* global tests shouldn't care about events on child only the specific event */ __u32 test_mask = (mask & ~FS_EVENT_ON_CHILD); /* if no fsnotify listeners, nothing to do */ if (list_empty(&fsnotify_inode_groups) && list_empty(&fsnotify_vfsmount_groups)) - return; + return 0; if (mask & FS_MODIFY) __fsnotify_flush_ignored_mask(to_tell, data, data_is); @@ -227,7 +222,7 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, /* if none of the directed listeners or vfsmount listeners care */ if (!(test_mask & fsnotify_inode_mask) && !(test_mask & fsnotify_vfsmount_mask)) - return; + return 0; if (data_is == FSNOTIFY_EVENT_PATH) mnt = ((struct path *)data)->mnt; @@ -236,7 +231,7 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, * listeners list cares, nothing to do */ if (!(test_mask & to_tell->i_fsnotify_mask) && !needed_by_vfsmount(test_mask, mnt)) - return; + return 0; /* * SRCU!! the groups list is very very much read only and the path is @@ -248,20 +243,24 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, if (test_mask & to_tell->i_fsnotify_mask) { list_for_each_entry_rcu(group, &fsnotify_inode_groups, inode_group_list) { if (test_mask & group->mask) { - send_to_group(group, to_tell, NULL, mask, data, data_is, - cookie, file_name, &event); + ret = send_to_group(group, to_tell, NULL, mask, data, data_is, + cookie, file_name, &event); + if (ret) + goto out; } } } if (needed_by_vfsmount(test_mask, mnt)) { list_for_each_entry_rcu(group, &fsnotify_vfsmount_groups, vfsmount_group_list) { if (test_mask & group->mask) { - send_to_group(group, to_tell, mnt, mask, data, data_is, - cookie, file_name, &event); + ret = send_to_group(group, to_tell, mnt, mask, data, data_is, + cookie, file_name, &event); + if (ret) + goto out; } } } - +out: srcu_read_unlock(&fsnotify_grp_srcu, idx); /* * fsnotify_create_event() took a reference so the event can't be cleaned @@ -269,6 +268,8 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, */ if (event) fsnotify_put_event(event); + + return 0; } EXPORT_SYMBOL_GPL(fsnotify); diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index b8cf161f5a6..64efda9aae6 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -34,6 +34,25 @@ static inline void fsnotify_parent(struct path *path, struct dentry *dentry, __u __fsnotify_parent(path, dentry, mask); } +/* simple call site for access decisions */ +static inline int fsnotify_perm(struct file *file, int mask) +{ + struct path *path = &file->f_path; + struct inode *inode = path->dentry->d_inode; + __u32 fsnotify_mask; + + if (file->f_mode & FMODE_NONOTIFY) + return 0; + if (!(mask & (MAY_READ | MAY_OPEN))) + return 0; + if (mask & MAY_READ) + fsnotify_mask = FS_ACCESS_PERM; + if (mask & MAY_OPEN) + fsnotify_mask = FS_OPEN_PERM; + + return fsnotify(inode, fsnotify_mask, path, FSNOTIFY_EVENT_PATH, NULL, 0); +} + /* * fsnotify_d_move - dentry has been moved * Called with dcache_lock and dentry->d_lock held. diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index efe9ba321cf..c34728e7d8c 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -41,6 +41,9 @@ #define FS_Q_OVERFLOW 0x00004000 /* Event queued overflowed */ #define FS_IN_IGNORED 0x00008000 /* last inotify event here */ +#define FS_OPEN_PERM 0x00010000 /* open event in an permission hook */ +#define FS_ACCESS_PERM 0x00020000 /* access event in a permissions hook */ + #define FS_IN_ISDIR 0x40000000 /* event occurred against dir */ #define FS_IN_ONESHOT 0x80000000 /* only send event once */ @@ -282,8 +285,8 @@ struct fsnotify_mark { /* called from the vfs helpers */ /* main fsnotify call to send events */ -extern void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, - const unsigned char *name, u32 cookie); +extern int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, + const unsigned char *name, u32 cookie); extern void __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask); extern void __fsnotify_inode_delete(struct inode *inode); extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt); @@ -413,9 +416,11 @@ extern int fsnotify_replace_event(struct fsnotify_event_holder *old_holder, #else -static inline void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, - const unsigned char *name, u32 cookie) -{} +static inline int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, + const unsigned char *name, u32 cookie) +{ + return 0; +} static inline void __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) {} diff --git a/include/linux/security.h b/include/linux/security.h index 0c881917046..24fc29540aa 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -23,6 +23,7 @@ #define __LINUX_SECURITY_H #include <linux/fs.h> +#include <linux/fsnotify.h> #include <linux/binfmts.h> #include <linux/signal.h> #include <linux/resource.h> diff --git a/security/security.c b/security/security.c index 351942a4ca0..f6ac27cd345 100644 --- a/security/security.c +++ b/security/security.c @@ -620,7 +620,13 @@ void security_inode_getsecid(const struct inode *inode, u32 *secid) int security_file_permission(struct file *file, int mask) { - return security_ops->file_permission(file, mask); + int ret; + + ret = security_ops->file_permission(file, mask); + if (ret) + return ret; + + return fsnotify_perm(file, mask); } int security_file_alloc(struct file *file) @@ -684,7 +690,13 @@ int security_file_receive(struct file *file) int security_dentry_open(struct file *file, const struct cred *cred) { - return security_ops->dentry_open(file, cred); + int ret; + + ret = security_ops->dentry_open(file, cred); + if (ret) + return ret; + + return fsnotify_perm(file, MAY_OPEN); } int security_task_create(unsigned long clone_flags) |