kernel/git/stable/linux.git/fs/fuse/file.c, branch linux-4.12.y

fuse: allow server to run in different pid_ns

2017-09-20T06:22:11+00:00

commit 5d6d3a301c4e749e04be6fcdcf4cb1ffa8bae524 upstream. Commit 0b6e9ea041e6 ("fuse: Add support for pid namespaces") broke Sandstorm.io development tools, which have been sending FUSE file descriptors across PID namespace boundaries since early 2014. The above patch added a check that prevented I/O on the fuse device file descriptor if the pid namespace of the reader/writer was different from the pid namespace of the mounter. With this change passing the device file descriptor to a different pid namespace simply doesn't work. The check was added because pids are transferred to/from the fuse userspace server in the namespace registered at mount time. To fix this regression, remove the checks and do the following: 1) the pid in the request header (the pid of the task that initiated the filesystem operation) is translated to the reader's pid namespace. If a mapping doesn't exist for this pid, then a zero pid is used. Note: even if a mapping would exist between the initiator task's pid namespace and the reader's pid namespace the pid will be zero if either mapping from initator's to mounter's namespace or mapping from mounter's to reader's namespace doesn't exist. 2) The lk.pid value in setlk/setlkw requests and getlk reply is left alone. Userspace should not interpret this value anyway. Also allow the setlk/setlkw operations if the pid of the task cannot be represented in the mounter's namespace (pid being zero in that case). Reported-by: Kenton Varda Signed-off-by: Miklos Szeredi Fixes: 0b6e9ea041e6 ("fuse: Add support for pid namespaces") Cc: Eric W. Biederman Cc: Seth Forshee Signed-off-by: Greg Kroah-Hartman

fuse: initialize the flock flag in fuse_file on allocation

2017-08-16T20:46:51+00:00

commit 68227c03cba84a24faf8a7277d2b1a03c8959c2c upstream. Before the patch, the flock flag could remain uninitialized for the lifespan of the fuse_file allocation. Unless set to true in fuse_file_flock(), it would remain in an indeterminate state until read in an if statement in fuse_release_common(). This could consequently lead to taking an unexpected branch in the code. The bug was discovered by a runtime instrumentation designed to detect use of uninitialized memory in the kernel. Signed-off-by: Mateusz Jurczyk Fixes: 37fb3a30b462 ("fuse: fix flock") Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman

Merge tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2017-05-10T20:03:38+00:00

Pull NFS client updates from Trond Myklebust: "Highlights include: Stable bugfixes: - Fix use after free in write error path - Use GFP_NOIO for two allocations in writeback - Fix a hang in OPEN related to server reboot - Check the result of nfs4_pnfs_ds_connect - Fix an rcu lock leak Features: - Removal of the unmaintained and unused OSD pNFS layout - Cleanup and removal of lots of unnecessary dprintk()s - Cleanup and removal of some memory failure paths now that GFP_NOFS is guaranteed to never fail. - Remove the v3-only data server limitation on pNFS/flexfiles Bugfixes: - RPC/RDMA connection handling bugfixes - Copy offload: fixes to ensure the copied data is COMMITed to disk. - Readdir: switch back to using the ->iterate VFS interface - File locking fixes from Ben Coddington - Various use-after-free and deadlock issues in pNFS - Write path bugfixes" * tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (89 commits) pNFS/flexfiles: Always attempt to call layoutstats when flexfiles is enabled NFSv4.1: Work around a Linux server bug... NFS append COMMIT after synchronous COPY NFSv4: Fix exclusive create attributes encoding NFSv4: Fix an rcu lock leak nfs: use kmap/kunmap directly NFS: always treat the invocation of nfs_getattr as cache hit when noac is on Fix nfs_client refcounting if kmalloc fails in nfs4_proc_exchange_id and nfs4_proc_async_renew NFSv4.1: RECLAIM_COMPLETE must handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION pNFS: Fix NULL dereference in pnfs_generic_alloc_ds_commits pNFS: Fix a typo in pnfs_generic_alloc_ds_commits pNFS: Fix a deadlock when coalescing writes and returning the layout pNFS: Don't clear the layout return info if there are segments to return pNFS: Ensure we commit the layout if it has been invalidated pNFS: Don't send COMMITs to the DSes if the server invalidated our layout pNFS/flexfiles: Fix up the ff_layout_write_pagelist failure path pNFS: Ensure we check layout validity before marking it for return NFS4.1 handle interrupted slot reuse from ERR_DELAY NFSv4: check return value of xdr_inline_decode nfs/filelayout: fix NULL pointer dereference in fl_pnfs_update_layout() ...

locks: Set FL_CLOSE when removing flock locks on close()

2017-04-21T14:45:01+00:00

Set FL_CLOSE in fl_flags as in locks_remove_posix() when clearing locks. NFS will check for this flag to ensure an unlock is sent in a following patch. Fuse handles flock and posix locks differently for FL_CLOSE, and so requires a fixup to retain the existing behavior for flock. Signed-off-by: Benjamin Coddington Reviewed-by: Jeff Layton Acked-by: Miklos Szeredi Signed-off-by: Trond Myklebust

fuse: Add support for pid namespaces

2017-04-18T14:58:38+00:00

When the userspace process servicing fuse requests is running in a pid namespace then pids passed via the fuse fd are not being translated into that process' namespace. Translation is necessary for the pid to be useful to that process. Since no use case currently exists for changing namespaces all translations can be done relative to the pid namespace in use when fuse_conn_init() is called. For fuse this translates to mount time, and for cuse this is when /dev/cuse is opened. IO for this connection from another namespace will return errors. Requests from processes whose pid cannot be translated into the target namespace will have a value of 0 for in.h.pid. File locking changes based on previous work done by Eric Biederman. Signed-off-by: Seth Forshee Signed-off-by: Miklos Szeredi

fuse: convert fuse_file.count from atomic_t to refcount_t

2017-04-18T14:58:37+00:00

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 Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: Miklos Szeredi

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

2017-03-03T20:14:13+00:00

Pull fuse update from Miklos Szeredi: "A bugfix and cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: release: private_data cannot be NULL fuse: cleanup fuse_file refcounting fuse: add missing FR_FORCE

mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf

2017-02-25T01:46:54+00:00

->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to take a vma and vmf parameter when the vma already resides in vmf. Remove the vma parameter to simplify things. [arnd@arndb.de: fix ARM build] Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang Signed-off-by: Arnd Bergmann Reviewed-by: Ross Zwisler Cc: Theodore Ts'o Cc: Darrick J. Wong Cc: Matthew Wilcox Cc: Dave Hansen Cc: Christoph Hellwig Cc: Jan Kara Cc: Dan Williams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fuse: release: private_data cannot be NULL

2017-02-22T19:08:25+00:00

Signed-off-by: Miklos Szeredi

fuse: cleanup fuse_file refcounting

2017-02-22T19:08:25+00:00

struct fuse_file is stored in file->private_data. Make this always be a counting reference for consistency. This also allows fuse_sync_release() to call fuse_file_put() instead of partially duplicating its functionality. Signed-off-by: Miklos Szeredi