linux/fs/debugfs, branch v3.15

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2014-04-04T22:39:39Z

Pull ext4 updates from Ted Ts'o: "Major changes for 3.14 include support for the newly added ZERO_RANGE and COLLAPSE_RANGE fallocate operations, and scalability improvements in the jbd2 layer and in xattr handling when the extended attributes spill over into an external block. Other than that, the usual clean ups and minor bug fixes" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (42 commits) ext4: fix premature freeing of partial clusters split across leaf blocks ext4: remove unneeded test of ret variable ext4: fix comment typo ext4: make ext4_block_zero_page_range static ext4: atomically set inode->i_flags in ext4_set_inode_flags() ext4: optimize Hurd tests when reading/writing inodes ext4: kill i_version support for Hurd-castrated file systems ext4: each filesystem creates and uses its own mb_cache fs/mbcache.c: doucple the locking of local from global data fs/mbcache.c: change block and index hash chain to hlist_bl_node ext4: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate ext4: refactor ext4_fallocate code ext4: Update inode i_size after the preallocation ext4: fix partial cluster handling for bigalloc file systems ext4: delete path dealloc code in ext4_ext_handle_uninitialized_extents ext4: only call sync_filesystm() when remounting read-only fs: push sync_filesystem() down to the file system's remount_fs() jbd2: improve error messages for inconsistent journal heads jbd2: minimize region locked by j_list_lock in jbd2_journal_forget() jbd2: minimize region locked by j_list_lock in journal_get_create_access() ...

fs: push sync_filesystem() down to the file system's remount_fs()

2014-03-13T14:14:33Z

Previously, the no-op "mount -o mount /dev/xxx" operation when the file system is already mounted read-write causes an implied, unconditional syncfs(). This seems pretty stupid, and it's certainly documented or guaraunteed to do this, nor is it particularly useful, except in the case where the file system was mounted rw and is getting remounted read-only. However, it's possible that there might be some file systems that are actually depending on this behavior. In most file systems, it's probably fine to only call sync_filesystem() when transitioning from read-write to read-only, and there are some file systems where this is not needed at all (for example, for a pseudo-filesystem or something like romfs). Signed-off-by: "Theodore Ts'o" Cc: linux-fsdevel@vger.kernel.org Cc: Christoph Hellwig Cc: Artem Bityutskiy Cc: Adrian Hunter Cc: Evgeniy Dushistov Cc: Jan Kara Cc: OGAWA Hirofumi Cc: Anders Larsen Cc: Phillip Lougher Cc: Kees Cook Cc: Mikulas Patocka Cc: Petr Vandrovec Cc: xfs@oss.sgi.com Cc: linux-btrfs@vger.kernel.org Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Cc: codalist@coda.cs.cmu.edu Cc: linux-ext4@vger.kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net Cc: fuse-devel@lists.sourceforge.net Cc: cluster-devel@redhat.com Cc: linux-mtd@lists.infradead.org Cc: jfs-discussion@lists.sourceforge.net Cc: linux-nfs@vger.kernel.org Cc: linux-nilfs@vger.kernel.org Cc: linux-ntfs-dev@lists.sourceforge.net Cc: ocfs2-devel@oss.oracle.com Cc: reiserfs-devel@vger.kernel.org

treewide: Fix typo in Documentation/DocBook

2014-02-19T13:58:17Z

This patch fix spelling typo in Documentation/DocBook. It is because .html and .xml files are generated by make htmldocs, I have to fix a typo within the source files. Signed-off-by: Masanari Iida Acked-by: Randy Dunlap Signed-off-by: Jiri Kosina

debugfs: use list_next_entry() in debugfs_remove_recursive()

2013-11-13T03:09:24Z

Change debugfs_remove_recursive() to use list_next_entry(child), no changes in generated code. Signed-off-by: Oleg Nesterov Cc: Eilon Greenstein Cc: Greg Kroah-Hartman Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

debugfs: debugfs_remove_recursive() must not rely on list_empty(d_subdirs)

2013-07-31T16:16:31Z

debugfs_remove_recursive() is wrong, 1. it wrongly assumes that !list_empty(d_subdirs) means that this dir should be removed. This is not that bad by itself, but: 2. if d_subdirs does not becomes empty after __debugfs_remove() it gives up and silently fails, it doesn't even try to remove other entries. However ->d_subdirs can be non-empty because it still has the already deleted !debugfs_positive() entries. 3. simple_release_fs() is called even if __debugfs_remove() fails. Suppose we have dir1/ dir2/ file2 file1 and someone opens dir1/dir2/file2. Now, debugfs_remove_recursive(dir1/dir2) succeeds, and dir1/dir2 goes away. But debugfs_remove_recursive(dir1) silently fails and doesn't remove this directory. Because it tries to delete (the already deleted) dir1/dir2/file2 again and then fails due to "Avoid infinite loop" logic. Test-case: #!/bin/sh cd /sys/kernel/debug/tracing echo 'p:probe/sigprocmask sigprocmask' >> kprobe_events sleep 1000 < events/probe/sigprocmask/id & echo -n >| kprobe_events [ -d events/probe ] && echo "ERR!! failed to rm probe" And after that it is not possible to create another probe entry. With this patch debugfs_remove_recursive() skips !debugfs_positive() files although this is not strictly needed. The most important change is that it does not try to make ->d_subdirs empty, it simply scans the whole list(s) recursively and removes as much as possible. Link: http://lkml.kernel.org/r/20130726151256.GC19472@redhat.com Acked-by: Greg Kroah-Hartman Signed-off-by: Oleg Nesterov Signed-off-by: Steven Rostedt

debugfs: write_file_bool() - ensure strtobool() operates on valid data

2013-06-03T20:55:02Z

In case, userland writes an empty string to a bool debugfs file, buf[] will still be uninitialized when being passed to strtobool() making the outcome of that function purely random. Fix this by always zero-terminating the buffer. Signed-off-by: Mathias Krause Signed-off-by: Greg Kroah-Hartman

debugfs: add get/set for atomic types

2013-06-03T20:55:01Z

debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings Acked-by: Greg Kroah-Hartman Acked-by: Mel Gorman Acked-by: Rik van Riel Acked-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman

fs: Limit sys_mount to only request filesystem modules.

2013-03-04T03:36:31Z

Modify the request_module to prefix the file system type with "fs-" and add aliases to all of the filesystems that can be built as modules to match. A common practice is to build all of the kernel code and leave code that is not commonly needed as modules, with the result that many users are exposed to any bug anywhere in the kernel. Looking for filesystems with a fs- prefix limits the pool of possible modules that can be loaded by mount to just filesystems trivially making things safer with no real cost. Using aliases means user space can control the policy of which filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf with blacklist and alias directives. Allowing simple, safe, well understood work-arounds to known problematic software. This also addresses a rare but unfortunate problem where the filesystem name is not the same as it's module name and module auto-loading would not work. While writing this patch I saw a handful of such cases. The most significant being autofs that lives in the module autofs4. This is relevant to user namespaces because we can reach the request module in get_fs_type() without having any special permissions, and people get uncomfortable when a user specified string (in this case the filesystem type) goes all of the way to request_module. After having looked at this issue I don't think there is any particular reason to perform any filtering or permission checks beyond making it clear in the module request that we want a filesystem module. The common pattern in the kernel is to call request_module() without regards to the users permissions. In general all a filesystem module does once loaded is call register_filesystem() and go to sleep. Which means there is not much attack surface exposed by loading a filesytem module unless the filesystem is mounted. In a user namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT, which most filesystems do not set today. Acked-by: Serge Hallyn Acked-by: Kees Cook Reported-by: Kees Cook Signed-off-by: "Eric W. Biederman"

Merge 3.9-rc4 into driver-core-next

2013-01-18T03:48:18Z

This is to fix up a build problem with a wireless driver due to the dynamic-debug patches in this branch. Signed-off-by: Greg Kroah-Hartman

debugfs: remove redundant initialization of dentry

2013-01-17T21:02:08Z

We already initialize it to NULL when declaring it, no need to do that twice. Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman