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* [PATCH] capable/capability.h (fs/)Randy Dunlap2006-01-111-0/+1
| | | | | | | | | fs: Use <linux/capability.h> where capable() is used. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_semJes Sorensen2006-01-091-41/+41
| | | | | | | | | | | | | This patch converts the inode semaphore to a mutex. I have tested it on XFS and compiled as much as one can consider on an ia64. Anyway your luck with it might be different. Modified-by: Ingo Molnar <mingo@elte.hu> (finished the conversion) Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* [PATCH] Fix some problems with truncate and mtime semantics.NeilBrown2006-01-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SUS requires that when truncating a file to the size that it currently is: truncate and ftruncate should NOT modify ctime or mtime O_TRUNC SHOULD modify ctime and mtime. Currently mtime and ctime are always modified on most local filesystems (side effect of ->truncate) or never modified (on NFS). With this patch: ATTR_CTIME|ATTR_MTIME are sent with ATTR_SIZE precisely when an update of these times is required whether size changes or not (via a new argument to do_truncate). This allows NFS to do the right thing for O_TRUNC. inode_setattr nolonger forces ATTR_MTIME|ATTR_CTIME when the ATTR_SIZE sets the size to it's current value. This allows local filesystems to do the right thing for f?truncate. Also, the logic in inode_setattr is changed a bit so there are two return points. One returns the error from vmtruncate if it failed, the other returns 0 (there can be no other failure). Finally, if vmtruncate succeeds, and ATTR_SIZE is the only change requested, we now fall-through and mark_inode_dirty. If a filesystem did not have a ->truncate function, then vmtruncate will have changed i_size, without marking the inode as 'dirty', and I think this is wrong. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fs/namei.c: make path_lookup_create() staticAdrian Bunk2005-11-091-2/+3
| | | | | | | | | | This patch makes the needlessly global function path_lookup_create() static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sanitize lookup_hash prototypeChristoph Hellwig2005-11-091-10/+10
| | | | | | | | | | | | | | | | | | | | | | | ->permission and ->lookup have a struct nameidata * argument these days to pass down lookup intents. Unfortunately some callers of lookup_hash don't actually pass this one down. For lookup_one_len() we don't have a struct nameidata to pass down, but as this function is a library function only used by filesystem code this is an acceptable limitation. All other callers should pass down the nameidata, so this patch changes the lookup_hash interface to only take a struct nameidata argument and derives the other two arguments to __lookup_hash from it. All callers already have the nameidata argument available so this is not a problem. At the same time I'd like to deprecate the lookup_hash interface as there are better exported interfaces for filesystem usage. Before it can actually be removed I need to fix up rpc_pipefs. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Ram Pai <linuxram@us.ibm.com> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Al Viro <viro@ftp.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] add a file_permission helperChristoph Hellwig2005-11-091-0/+18
| | | | | | | | | | | | A few more callers of permission() just want to check for a different access pattern on an already open file. This patch adds a wrapper for permission() that takes a file in preparation of per-mount read-only support and to clean up the callers a little. The helper is not intended for new code, everything without the interface set in stone should use vfs_permission() Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] add a vfs_permission helperChristoph Hellwig2005-11-091-4/+19
| | | | | | | | | | | Most permission() calls have a struct nameidata * available. This helper takes that as an argument and thus makes sure we pass it down for lookup intents and prepares for per-mount read-only support where we need a struct vfsmount for checking whether a file is writeable. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] VFS: pass file pointer to filesystem from ftruncate()Miklos Szeredi2005-11-071-1/+1
| | | | | | | | | | | | | | This patch extends the iattr structure with a file pointer memeber, and adds an ATTR_FILE validity flag for this member. This is set if do_truncate() is invoked from ftruncate() or from do_coredump(). The change is source and binary compatible. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] open: cleanup in lookup_flags()Miklos Szeredi2005-10-301-6/+0
| | | | | | | | | | | lookup_flags() is only called from the non-create case, so it needn't check for O_CREAT|O_EXCL. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* VFS: Make link_path_walk set LOOKUP_CONTINUE before calling permission().Trond Myklebust2005-10-181-1/+1
| | | | | | | | This will allow nfs_permission() to perform additional optimizations when walking the path, by folding the ACCESS(MAY_EXEC) call on the directory into the lookup revalidation. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* VFS: Allow the filesystem to return a full file pointer on open intentTrond Myklebust2005-10-181-7/+86
| | | | | | | | | This is needed by NFSv4 for atomicity reasons: our open command is in fact a lookup+open, so we need to be able to propagate open context information from lookup() into the resulting struct file's private_data field. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* Avoid 'names_cache' memory leak with CONFIG_AUDITSYSCALLLinus Torvalds2005-10-061-3/+3
| | | | | | | | | | | | | | | | The nameidata "last.name" is always allocated with "__getname()", and should always be free'd with "__putname()". Using "putname()" without the underscores will leak memory, because the allocation will have been hidden from the AUDITSYSCALL code. Arguably the real bug is that the AUDITSYSCALL code is really broken, but in the meantime this fixes the problem people see. Reported by Robert Derr, patch by Rick Lindsley. Acked-by: Al Viro <viro@ftp.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Merge master.kernel.org:/pub/scm/linux/kernel/git/dwmw2/audit-2.6 Linus Torvalds2005-09-131-1/+1
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| * Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse2005-08-271-19/+21
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| * \ Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse2005-08-171-1/+2
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| * \ \ Merge with /shiny/git/linux-2.6/.gitDavid Woodhouse2005-08-091-3/+1
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| * \ \ \ Merge with /shiny/git/linux-2.6/.gitDavid Woodhouse2005-07-131-15/+17
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| * \ \ \ \ Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse2005-07-021-2/+18
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| * | | | | | AUDIT: Report lookup flags with path/inode records.David Woodhouse2005-06-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When LOOKUP_PARENT is used, the inode which results is not the inode found at the pathname. Report the flags so that this doesn't generate misleading audit records. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* | | | | | | [PATCH] remove the inode_post_link and inode_post_rename LSM hooksStephen Smalley2005-09-091-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes the inode_post_link and inode_post_rename LSM hooks as they are unused (and likely useless). Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | | | | [PATCH] Remove security_inode_post_create/mkdir/symlink/mknod hooksStephen Smalley2005-09-091-12/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as they are obsoleted by the new inode_init_security hook that enables atomic inode security labeling. If anyone sees any reason to retain these hooks, please speak now. Also, is anyone using the post_rename/link hooks; if not, those could also be removed. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | | | | [PATCH] namei cleanupMiklos Szeredi2005-09-071-28/+24
| |_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extract common code into inline functions to make reading easier. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: <viro@parcelfarce.linux.theplanet.co.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | | | Fix nasty ncpfs symlink handling bug.Linus Torvalds2005-08-191-19/+21
| |_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This bug could cause oopses and page state corruption, because ncpfs used the generic page-cache symlink handlign functions. But those functions only work if the page cache is guaranteed to be "stable", ie a page that was installed when the symlink walk was started has to still be installed in the page cache at the end of the walk. We could have fixed ncpfs to not use the generic helper routines, but it is in many ways much cleaner to instead improve on the symlink walking helper routines so that they don't require that absolute stability. We do this by allowing "follow_link()" to return a error-pointer as a cookie, which is fed back to the cleanup "put_link()" routine. This also simplifies NFS symlink handling. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | | [PATCH] inotify: add MOVE_SELF eventJohn McCutchan2005-08-151-1/+2
| |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a MOVE_SELF event to inotify. It is sent whenever the inode you are watching is moved. We need this event so that we can catch something like this: - app1: watch /etc/mtab - app2: cp /etc/mtab /tmp/mtab-work mv /etc/mtab /etc/mtab~ mv /tmp/mtab-work /etc/mtab app1 still thinks it's watching /etc/mtab but it's actually watching /etc/mtab~. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Robert Love <rml@novell.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | [PATCH] fsnotify_name/inoderemoveJohn McCutchan2005-08-081-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch below unhooks fsnotify from vfs_unlink & vfs_rmdir. It introduces two new fsnotify calls, that are hooked in at the dcache level. This not only more closely matches how the VFS layer works, it also avoids the problem with locking and inode lifetimes. The two functions are - fsnotify_nameremove -- called when a directory entry is going away. It notifies the PARENT of the deletion. This is called from d_delete(). - inoderemove -- called when the files inode itself is going away. It notifies the inode that is being deleted. This is called from dentry_iput(). Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | [PATCH] Clean up inotify delete race fixJohn McCutchan2005-08-041-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This avoids the whole #ifdef mess by just getting a copy of dentry->d_inode before d_delete is called - that makes the codepaths the same for the INOTIFY/DNOTIFY cases as for the regular no-notify case. I've been running this under a Gnome session for the last 10 minutes. Inotify is being used extensively. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | [PATCH] inotify delete race fixJohn McCutchan2005-08-041-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The included patch fixes a problem where a inotify client would receive a delete event before the file was actually deleted. The bug affects both dnotify & inotify. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Robert Love <rml@novell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | | [PATCH] inotify: fix file deletion by rename detectionJohn McCutchan2005-08-011-1/+1
| |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | When a file is moved over an existing file that you are watching, inotify won't send you a DELETE_SELF event and it won't unref the inode until the inotify instance is closed by the application. Signed-off-by: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Robert Love <rml@novell.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | [PATCH] inotifyRobert Love2005-07-121-14/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | inotify is intended to correct the deficiencies of dnotify, particularly its inability to scale and its terrible user interface: * dnotify requires the opening of one fd per each directory that you intend to watch. This quickly results in too many open files and pins removable media, preventing unmount. * dnotify is directory-based. You only learn about changes to directories. Sure, a change to a file in a directory affects the directory, but you are then forced to keep a cache of stat structures. * dnotify's interface to user-space is awful. Signals? inotify provides a more usable, simple, powerful solution to file change notification: * inotify's interface is a system call that returns a fd, not SIGIO. You get a single fd, which is select()-able. * inotify has an event that says "the filesystem that the item you were watching is on was unmounted." * inotify can watch directories or files. Inotify is currently used by Beagle (a desktop search infrastructure), Gamin (a FAM replacement), and other projects. See Documentation/filesystems/inotify.txt. Signed-off-by: Robert Love <rml@novell.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | | [PATCH] namespace: rename _mntput to mntput_no_expireMiklos Szeredi2005-07-071-1/+1
| |/ |/| | | | | | | | | | | | | | | | | This patch renames _mntput() to something a little more descriptive: mntput_no_expire(). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] add some comments to lookup_create()Christoph Hellwig2005-06-231-2/+18
|/ | | | | | | | | In a duplicate of lookup_create in the af_unix code Al commented what's going on nicely, so let's bring that over to lookup_create before the copy is going away (I'll send a patch soon) Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (19/19)Al Viro2005-06-061-1/+1
| | | | | | | | | | __do_follow_link() passes potentially worng vfsmount to touch_atime(). It matters only in (currently impossible) case of symlink mounted on something, but it's trivial to fix and that actually makes more sense. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (18/19)Al Viro2005-06-061-3/+1
| | | | | | | | | | | Cosmetical cleanups - __follow_mount() calls in __link_path_walk() absorbed into do_lookup(). Obviously equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (17/19)Al Viro2005-06-061-19/+16
| | | | | | | | | | | | | follow_mount() made void, reordered dput()/mntput() in it. follow_dotdot() switched from struct vfmount ** + struct dentry ** to struct nameidata *; callers updated. Equivalent transformation + fix for too-early-mntput() race. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (16/19)Al Viro2005-06-061-5/+2
| | | | | | | | | | Conditional mntput() moved into __do_follow_link(). There it collapses with unconditional mntget() on the same sucker, closing another too-early-mntput() race. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (15/19)Al Viro2005-06-061-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | Getting rid of sloppy logics: a) in do_follow_link() we have the wrong vfsmount dropped if our symlink had been mounted on something. Currently it worls only because we never get such situation (modulo filesystem playing dirty tricks on us). And it obfuscates already convoluted logics... b) same goes for open_namei(). c) in __link_path_walk() we have another "it should never happen" sloppiness - out_dput: there does double-free on underlying vfsmount and leaks the covering one if we hit it just after crossing a mountpoint. Again, wrong vfsmount getting dropped. d) another too-early-mntput() race - in do_follow_mount() we need to postpone conditional mntput(path->mnt) until after dput(path->dentry). Again, this one happens only in it-currently-never-happens-unless-some-fs-plays-dirty scenario... Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (14/19)Al Viro2005-06-061-4/+4
| | | | | | | | | | | shifted conditional mntput() into do_follow_link() - all callers were doing the same thing. Obviously equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (13/19)Al Viro2005-06-061-7/+3
| | | | | | | | | | | | | | | | | | In open_namei() exit_dput: we have mntput() done in the wrong order - if nd->mnt != path.mnt we end up doing mntput(nd->mnt); nd->mnt = path.mnt; dput(nd->dentry); mntput(nd->mnt); which drops nd->dentry too late. Fixed by having path.mnt go first. That allows to switch O_NOFOLLOW under if (__follow_mount(...)) back to exit_dput, while we are at it. Fix for early-mntput() race + equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (12/19)Al Viro2005-06-061-2/+9
| | | | | | | | | | | | | In open_namei() we take mntput(nd->mnt);nd->mnt=path.mnt; out of the if (__follow_mount(...)), making it conditional on nd->mnt != path.mnt instead. Then we shift the result downstream. Equivalent transformations. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (11/19)Al Viro2005-06-061-4/+10
| | | | | | | | | | shifted conditional mntput() calls in __link_path_walk() downstream. Obviously equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (10/19)Al Viro2005-06-061-11/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In open_namei(), __follow_down() loop turned into __follow_mount(). Instead of if we are on a mountpoint dentry if O_NOFOLLOW checks fail drop path.dentry drop nd return do equivalent of follow_mount(&path.mnt, &path.dentry) nd->mnt = path.mnt we do if __follow_mount(path) had, indeed, traversed mountpoint /* now both nd->mnt and path.mnt are pinned down */ if O_NOFOLLOW checks fail drop path.dentry drop path.mnt drop nd return mntput(nd->mnt) nd->mnt = path.mnt Now __follow_down() can be folded into follow_down() - no other callers left. We need to reorder dput()/mntput() there - same problem as in follow_mount(). Equivalent transformation + fix for a bug in O_NOFOLLOW handling - we used to get -ELOOP if we had the same fs mounted on /foo and /bar, had something bound on /bar/baz and tried to open /foo/baz with O_NOFOLLOW. And fix of too-early-mntput() race in follow_down() Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (9/19)Al Viro2005-06-061-2/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | New helper: __follow_mount(struct path *path). Same as follow_mount(), except that we do *not* do mntput() after the first lookup_mnt(). IOW, original path->mnt stays pinned down. We also take care to do dput() before mntput() in the loop body (follow_mount() also needs that reordering, but that will be done later in the series). The following are equivalent, assuming that path.mnt == x: (1) follow_mount(&path.mnt, &path.dentry) (2) __follow_mount(&path); if (path->mnt != x) mntput(x); (3) if (__follow_mount(&path)) mntput(x); Callers of follow_mount() in __link_path_walk() converted to (2). Equivalent transformation + fix for too-late-mntput() race in __follow_mount() loop. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (8/19)Al Viro2005-06-061-4/+2
| | | | | | | | | | | | | | In open_namei() we never use path.mnt or path.dentry after exit: or ok:. Assignment of path.dentry in case of LAST_BIND is dead code and only obfuscates already convoluted function; assignment of path.mnt after __do_follow_link() can be moved down to the place where we set path.dentry. Obviously equivalent transformations, just to clean the air a bit in that region. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (7/19)Al Viro2005-06-061-9/+8
| | | | | | | | | | | | | | The first argument of __do_follow_link() switched to struct path * (__do_follow_link(path->dentry, ...) -> __do_follow_link(path, ...)). All callers have the same calls of mntget() right before and dput()/mntput() right after __do_follow_link(); these calls have been moved inside. Obviously equivalent transformations. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (6/19)Al Viro2005-06-061-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mntget(path->mnt) in do_follow_link() moved down to right before the __do_follow_link() call and rigth after loop: resp. dput()+mntput() on non-ELOOP branch moved up to right after __do_follow_link() call. resulting loop: mntget(path->mnt); path_release(nd); dput(path->mnt); mntput(path->mnt); replaced with equivalent dput(path->mnt); path_release(nd); Equivalent transformations - the reason why we have that mntget() is that __do_follow_link() can drop a reference to nd->mnt and that's what holds path->mnt. So that call can happen at any point prior to __do_follow_link() touching nd->mnt. The rest is obvious. NOTE: current tree relies on symlinks *never* being mounted on anything. It's not hard to get rid of that assumption (actually, that will come for free later in the series). For now we are just not making the situation worse than it is. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (5/19)Al Viro2005-06-061-0/+2
| | | | | | | | | | | fix for too early mntput() in open_namei() - we pin path.mnt down for the duration of __do_follow_link(). Otherwise we could get the fs where our symlink lived unmounted while we were in __do_follow_link(). That would end up with dentry of symlink staying pinned down through the fs shutdown. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (4/19)Al Viro2005-06-061-1/+4
| | | | | | | | | | | | | | | | | | path.mnt in open_namei() set to mirror nd->mnt. nd->mnt is set in 3 places in that function - path_lookup() in the beginning, __follow_down() loop after do_last: and __do_follow_link() call after do_link:. We set path.mnt to nd->mnt after path_lookup() and __do_follow_link(). In __follow_down() loop we use &path.mnt instead of &nd->mnt and set nd->mnt to path.mnt immediately after that loop. Obviously equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (3/19)Al Viro2005-06-061-19/+19
| | | | | | | | | | | Replaced struct dentry *dentry in namei with struct path path. All uses of dentry replaced with path.dentry there. Obviously equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixes (2/19)Al Viro2005-06-061-6/+5
| | | | | | | | | | | | All callers of do_follow_link() do mntget() right before it and dput()+mntput() right after. These calls are moved inside do_follow_link() now. Obviously equivalent transformation. Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namei fixesAl Viro2005-06-061-10/+10
| | | | | | | | | | | | | | OK, here comes a patch series that hopefully should close all too-early-mntput() races in fs/namei.c. Entire area is convoluted as hell, so I'm splitting that series into _very_ small chunks. Patches alread in the tree close only (very wide) races in following symlinks (see "busy inodes after umount" thread some time ago). Unfortunately, quite a few narrower races of the same nature were not closed. Hopefully this should take care of all of them. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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