linux/fs/fuse/dev.c, branch v3.8

fuse: remove unused variable in fuse_try_move_page()

2013-01-17T12:09:59Z

The variables mapping,index are initialized but never used otherwise, so remove the unused variables. dpatch engine is used to auto generate this patch. (https://github.com/weiyj/dpatch) Signed-off-by: Wei Yongjun Signed-off-by: Miklos Szeredi

userns: Support fuse interacting with multiple user namespaces

2012-11-15T06:05:33Z

Use kuid_t and kgid_t in struct fuse_conn and struct fuse_mount_data. The connection between between a fuse filesystem and a fuse daemon is established when a fuse filesystem is mounted and provided with a file descriptor the fuse daemon created by opening /dev/fuse. For now restrict the communication of uids and gids between the fuse filesystem and the fuse daemon to the initial user namespace. Enforce this by verifying the file descriptor passed to the mount of fuse was opened in the initial user namespace. Ensuring the mount happens in the initial user namespace is not necessary as mounts from non-initial user namespaces are not yet allowed. In fuse_req_init_context convert the currrent fsuid and fsgid into the initial user namespace for the request that will be sent to the fuse daemon. In fuse_fill_attr convert the uid and gid passed from the fuse daemon from the initial user namespace into kuids and kgids. In iattr_to_fattr called from fuse_setattr convert kuids and kgids into the uids and gids in the initial user namespace before passing them to the fuse filesystem. In fuse_change_attributes_common called from fuse_dentry_revalidate, fuse_permission, fuse_geattr, and fuse_setattr, and fuse_iget convert the uid and gid from the fuse daemon into a kuid and a kgid to store on the fuse inode. By default fuse mounts are restricted to task whose uid, suid, and euid matches the fuse user_id and whose gid, sgid, and egid matches the fuse group id. Convert the user_id and group_id mount options into kuids and kgids at mount time, and use uid_eq and gid_eq to compare the in fuse_allow_task. Cc: Miklos Szeredi Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman

make get_file() return its argument

2012-09-27T01:10:25Z

simplifies a bunch of callers... Signed-off-by: Al Viro

fuse: fix retrieve length

2012-09-04T16:45:54Z

In some cases fuse_retrieve() would return a short byte count if offset was non-zero. The data returned was correct, though. Signed-off-by: Miklos Szeredi Cc: stable@vger.kernel.org

fuse: remove the second argument of k[un]map_atomic()

2012-03-20T13:48:22Z

Signed-off-by: Cong Wang

FUSE: Notifying the kernel of deletion.

2011-12-13T10:58:49Z

Allows a FUSE file-system to tell the kernel when a file or directory is deleted. If the specified dentry has the specified inode number, the kernel will unhash it. The current 'fuse_notify_inval_entry' does not cause the kernel to clean up directories that are in use properly, and as a result the users of those directories see incorrect semantics from the file-system. The error condition seen when 'fuse_notify_inval_entry' is used to notify of a deleted directory is avoided when 'fuse_notify_delete' is used instead. The following scenario demonstrates the difference: 1. User A chdirs into 'testdir' and starts reading 'testfile'. 2. User B rm -rf 'testdir'. 3. User B creates 'testdir'. 4. User C chdirs into 'testdir'. If you run the above within the same machine on any file-system (including fuse file-systems), there is no problem: user C is able to chdir into the new testdir. The old testdir is removed from the dentry tree, but still open by user A. If operations 2 and 3 are performed via the network such that the fuse file-system uses one of the notify functions to tell the kernel that the nodes are gone, then the following error occurs for user C while user A holds the original directory open: muirj@empacher:~> ls /test/testdir ls: cannot access /test/testdir: No such file or directory The issue here is that the kernel still has a dentry for testdir, and so it is requesting the attributes for the old directory, while the file-system is responding that the directory no longer exists. If on the other hand, if the file-system can notify the kernel that the directory is deleted using the new 'fuse_notify_delete' function, then the above ls will find the new directory as expected. Signed-off-by: John Muir Signed-off-by: Miklos Szeredi

fuse: fix fuse_retrieve

2011-12-13T09:36:59Z

Fix two bugs in fuse_retrieve(): - retrieving more than one page would yield repeated instances of the first page - if more than FUSE_MAX_PAGES_PER_REQ pages were requested than the request page array would overflow fuse_retrieve() was added in 2.6.36 and these bugs had been there since the beginning. Signed-off-by: Miklos Szeredi CC: stable@vger.kernel.org

fuse: fix memory leak

2011-09-12T18:47:10Z

kmemleak is reporting that 32 bytes are being leaked by FUSE: unreferenced object 0xe373b270 (size 32): comm "fusermount", pid 1207, jiffies 4294707026 (age 2675.187s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x27/0x50 [] kmem_cache_alloc+0xc5/0x180 [] fuse_alloc_forget+0x1e/0x20 [] fuse_alloc_inode+0xb0/0xd0 [] alloc_inode+0x1c/0x80 [] iget5_locked+0x8f/0x1a0 [] fuse_iget+0x72/0x1a0 [] fuse_get_root_inode+0x8a/0x90 [] fuse_fill_super+0x3ef/0x590 [] mount_nodev+0x3f/0x90 [] fuse_mount+0x15/0x20 [] mount_fs+0x1c/0xc0 [] vfs_kern_mount+0x41/0x90 [] do_kern_mount+0x39/0xd0 [] do_mount+0x2e5/0x660 [] sys_mount+0x66/0xa0 This leak report is consistent and happens once per boot on 3.1.0-rc5-dirty. This happens if a FORGET request is queued after the fuse device was released. Reported-by: Sitsofe Wheeler Signed-off-by: Miklos Szeredi Tested-by: Sitsofe Wheeler Signed-off-by: Linus Torvalds

fuse: check size of FUSE_NOTIFY_INVAL_ENTRY message

2011-08-24T08:20:17Z

FUSE_NOTIFY_INVAL_ENTRY didn't check the length of the write so the message processing could overrun and result in a "kernel BUG at fs/fuse/dev.c:629!" Reported-by: Han-Wen Nienhuys Signed-off-by: Miklos Szeredi CC: stable@kernel.org

mm: add replace_page_cache_page() function

2011-03-23T00:44:02Z

This function basically does: remove_from_page_cache(old); page_cache_release(old); add_to_page_cache_locked(new); Except it does this atomically, so there's no possibility for the "add" to fail because of a race. If memory cgroups are enabled, then the memory cgroup charge is also moved from the old page to the new. This function is currently used by fuse to move pages into the page cache on read, instead of copying the page contents. [minchan.kim@gmail.com: add freepage() hook to replace_page_cache_page()] Signed-off-by: Miklos Szeredi Acked-by: Rik van Riel Acked-by: KAMEZAWA Hiroyuki Cc: Mel Gorman Signed-off-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds