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path: root/fs/sysv/super.c
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2013-09-30sysv: Add forgotten superblock lock init for v7 fsLubomir Rintel
Superblock lock was replaced with (un)lock_super() removal, but left uninitialized for Seventh Edition UNIX filesystem in the following commit (3.7): c07cb01 sysv: drop lock/unlock super Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-13fs: Readd the fs module aliases.Eric W. Biederman
I had assumed that the only use of module aliases for filesystems prior to "fs: Limit sys_mount to only request filesystem modules." was in request_module. It turns out I was wrong. At least mkinitcpio in Arch linux uses these aliases. So readd the preexising aliases, to keep from breaking userspace. Userspace eventually will have to follow and use the same aliases the kernel does. So at some point we may be delete these aliases without problems. However that day is not today. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-04fs: Limit sys_mount to only request filesystem modules.Eric W. Biederman
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 <serge.hallyn@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Reported-by: Kees Cook <keescook@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-10-10sysv: drop lock/unlock superMarco Stornelli
Removed lock/unlock super. Added a new private s_lock mutex. Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-21switch open-coded instances of d_make_root() to new helperAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-21vfs: check i_nlink limits in vfs_{mkdir,rename_dir,link}Al Viro
New field of struct super_block - ->s_max_links. Maximal allowed value of ->i_nlink or 0; in the latter case all checks still need to be done in ->link/->mkdir/->rename instances. Note that this limit applies both to directoris and to non-directories. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-13switch sysvAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-07fs: dcache reduce branches in lookup pathNick Piggin
Reduce some branches and memory accesses in dcache lookup by adding dentry flags to indicate common d_ops are set, rather than having to check them. This saves a pointer memory access (dentry->d_op) in common path lookup situations, and saves another pointer load and branch in cases where we have d_op but not the particular operation. Patched with: git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2010-10-29new helper: mount_bdev()Al Viro
... and switch of the obvious get_sb_bdev() users to ->mount() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-11fs/sysv/super.c: add support for non-PDP11 v7 filesystemsLubomir Rintel
This adds byte order autodetection (of PDP-11 and LE filesystems). No attempt is made to detect big-endian filesystems -- were there any? Tested with PDP-11 v7 filesystems and PC-IX maintenance floppy. [akpm@linux-foundation.org: coding-style fixes] [AV: parser.h inclusion was a rudiment of discarded stuff] Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-11V7: Adjust sanity checks for some volumesLubomir Rintel
Newly mkfs-ed filesystems from Seventh Edition have last modification time set to zero, but are otherwise perfectly valid. Also, tighten up other sanity checks to filter out most filesystems with different bytesex than we're using. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-11Add v7 aliasLubomir Rintel
So that the module gets autoloaded when a v7 filesystem is mounted. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09sysv: do not mark superblock dirty on mountArtem Bityutskiy
I did not find any docs about this file-system, and I have no possibility to test my changes. Thus, this is untested. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-02-07iget: stop the SYSV filesystem from using iget() and read_inode()David Howells
Stop the SYSV filesystem from using iget() and read_inode(). Replace sysv_read_inode() with sysv_iget(), and call that instead of iget(). sysv_iget() then uses iget_locked() directly and returns a proper error code instead of an inode in the event of an error. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-22[PATCH] fs/sysv/: proper prototypes for 2 functionsAdrian Bunk
Add proper prototypes for sysv_{init,destroy}_icache() in sysv.h Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11[PATCH] fs/*: use BUILD_BUG_ONAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27[PATCH] fs: Conversions from kmalloc+memset to k(z|c)allocPanagiotis Issaris
Conversions from kmalloc+memset to kzalloc. Signed-off-by: Panagiotis Issaris <takis@issaris.org> Jffs2-bit-acked-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23[PATCH] VFS: Permit filesystem to override root dentry on mountDavid Howells
Extend the get_sb() filesystem operation to take an extra argument that permits the VFS to pass in the target vfsmount that defines the mountpoint. The filesystem is then required to manually set the superblock and root dentry pointers. For most filesystems, this should be done with simple_set_mnt() which will set the superblock pointer and then set the root dentry to the superblock's s_root (as per the old default behaviour). The get_sb() op now returns an integer as there's now no need to return the superblock pointer. This patch permits a superblock to be implicitly shared amongst several mount points, such as can be done with NFS to avoid potential inode aliasing. In such a case, simple_set_mnt() would not be called, and instead the mnt_root and mnt_sb would be set directly. The patch also makes the following changes: (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount pointer argument and return an integer, so most filesystems have to change very little. (*) If one of the convenience function is not used, then get_sb() should normally call simple_set_mnt() to instantiate the vfsmount. This will always return 0, and so can be tail-called from get_sb(). (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the dcache upon superblock destruction rather than shrink_dcache_anon(). This is required because the superblock may now have multiple trees that aren't actually bound to s_root, but that still need to be cleaned up. The currently called functions assume that the whole tree is rooted at s_root, and that anonymous dentries are not the roots of trees which results in dentries being left unculled. However, with the way NFS superblock sharing are currently set to be implemented, these assumptions are violated: the root of the filesystem is simply a dummy dentry and inode (the real inode for '/' may well be inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries with child trees. [*] Anonymous until discovered from another tree. (*) The documentation has been adjusted, including the additional bit of changing ext2_* into foo_* in the documentation. [akpm@osdl.org: convert ipath_fs, do other stuff] Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Nathan Scott <nathans@sgi.com> Cc: Roland Dreier <rolandd@cisco.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24[PATCH] fs: Use ARRAY_SIZE macroTobias Klauser
Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove a duplicate of ARRAY_SIZE. Some trailing whitespaces are also deleted. Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch> Cc: David Howells <dhowells@redhat.com> Cc: Dave Kleikamp <shaggy@austin.ibm.com> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: Chris Mason <mason@suse.com> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Nathan Scott <nathans@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!