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path: root/fs/namei.c
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2013-08-05fs: Allow unprivileged linkat(..., AT_EMPTY_PATH) aka flinkAndy Lutomirski
Every now and then someone proposes a new flink syscall, and this spawns a long discussion of whether it would be a security problem. I think that this is missing the point: flink is *already* allowed without privilege as long as /proc is mounted -- it's called AT_SYMLINK_FOLLOW. Now that O_TMPFILE is here, the ability to create a file with O_TMPFILE, write it, and link it in is very convenient. The only problem is that it requires that /proc be mounted so that you can do: linkat(AT_FDCWD, "/proc/self/fd/<tmpfd>", dfd, path, AT_SYMLINK_NOFOLLOW) This sucks -- it's much nicer to do: linkat(tmpfd, "", dfd, path, AT_EMPTY_PATH) Let's allow it. If this turns out to be excessively scary, it we could instead require that the inode in question be I_LINKABLE, but this seems pointless given the /proc situation Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-13Safer ABI for O_TMPFILEAl Viro
[suggested by Rasmus Villemoes] make O_DIRECTORY | O_RDWR part of O_TMPFILE; that will fail on old kernels in a lot more cases than what I came up with. And make sure O_CREAT doesn't get there... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29Don't pass inode to ->d_hash() and ->d_compare()Linus Torvalds
Instances either don't look at it at all (the majority of cases) or only want it to find the superblock (which can be had as dentry->d_sb). A few cases that want more are actually safe with dentry->d_inode - the only precaution needed is the check that it hadn't been replaced with NULL by rmdir() or by overwriting rename(), which case should be simply treated as cache miss. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29allow the temp files created by open() to be linked toAl Viro
O_TMPFILE | O_CREAT => linkat() with AT_SYMLINK_FOLLOW and /proc/self/fd/<n> as oldpath (i.e. flink()) will create a link O_TMPFILE | O_CREAT | O_EXCL => ENOENT on attempt to link those guys Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29[O_TMPFILE] it's still short a few helpers, but infrastructure should be OK ↵Al Viro
now... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29allow build_open_flags() to return an errorAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29do_last(): fix missing checks for LAST_BIND caseAl Viro
/proc/self/cwd with O_CREAT should fail with EISDIR. /proc/self/exe, OTOH, should fail with ENOTDIR when opened with O_DIRECTORY. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-15use can_lookup() instead of direct checks of ->i_op->lookupAl Viro
a couple of places got missed back when Linus has introduced that one... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-11Merge git://git.infradead.org/users/eparis/auditLinus Torvalds
Pull audit changes from Eric Paris: "Al used to send pull requests every couple of years but he told me to just start pushing them to you directly. Our touching outside of core audit code is pretty straight forward. A couple of interface changes which hit net/. A simple argument bug calling audit functions in namei.c and the removal of some assembly branch prediction code on ppc" * git://git.infradead.org/users/eparis/audit: (31 commits) audit: fix message spacing printing auid Revert "audit: move kaudit thread start from auditd registration to kaudit init" audit: vfs: fix audit_inode call in O_CREAT case of do_last audit: Make testing for a valid loginuid explicit. audit: fix event coverage of AUDIT_ANOM_LINK audit: use spin_lock in audit_receive_msg to process tty logging audit: do not needlessly take a lock in tty_audit_exit audit: do not needlessly take a spinlock in copy_signal audit: add an option to control logging of passwords with pam_tty_audit audit: use spin_lock_irqsave/restore in audit tty code helper for some session id stuff audit: use a consistent audit helper to log lsm information audit: push loginuid and sessionid processing down audit: stop pushing loginid, uid, sessionid as arguments audit: remove the old depricated kernel interface audit: make validity checking generic audit: allow checking the type of audit message in the user filter audit: fix build break when AUDIT_DEBUG == 2 audit: remove duplicate export of audit_enabled Audit: do not print error when LSMs disabled ...
2013-05-07audit: vfs: fix audit_inode call in O_CREAT case of do_lastJeff Layton
Jiri reported a regression in auditing of open(..., O_CREAT) syscalls. In older kernels, creating a file with open(..., O_CREAT) created audit_name records that looked like this: type=PATH msg=audit(1360255720.628:64): item=1 name="/abc/foo" inode=138810 dev=fd:00 mode=0100640 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:default_t:s0 type=PATH msg=audit(1360255720.628:64): item=0 name="/abc/" inode=138635 dev=fd:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:default_t:s0 ...in recent kernels though, they look like this: type=PATH msg=audit(1360255402.886:12574): item=2 name=(null) inode=264599 dev=fd:00 mode=0100640 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:default_t:s0 type=PATH msg=audit(1360255402.886:12574): item=1 name=(null) inode=264598 dev=fd:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:default_t:s0 type=PATH msg=audit(1360255402.886:12574): item=0 name="/abc/foo" inode=264598 dev=fd:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:default_t:s0 Richard bisected to determine that the problems started with commit bfcec708, but the log messages have changed with some later audit-related patches. The problem is that this audit_inode call is passing in the parent of the dentry being opened, but audit_inode is being called with the parent flag false. This causes later audit_inode and audit_inode_child calls to match the wrong entry in the audit_names list. This patch simply sets the flag to properly indicate that this inode represents the parent. With this, the audit_names entries are back to looking like they did before. Cc: <stable@vger.kernel.org> # v3.7+ Reported-by: Jiri Jaburek <jjaburek@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Test By: Richard Guy Briggs <rbriggs@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
2013-03-08vfs: don't BUG_ON() if following a /proc fd pseudo-symlink results in a symlinkLinus Torvalds
It's "normal" - it can happen if the file descriptor you followed was opened with O_NOFOLLOW. Reported-by: Dave Jones <davej@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-01constify path_get/path_put and fs_struct.c stuffAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry opJeff Layton
The following set of operations on a NFS client and server will cause server# mkdir a client# cd a server# mv a a.bak client# sleep 30 # (or whatever the dir attrcache timeout is) client# stat . stat: cannot stat `.': Stale NFS file handle Obviously, we should not be getting an ESTALE error back there since the inode still exists on the server. The problem is that the lookup code will call d_revalidate on the dentry that "." refers to, because NFS has FS_REVAL_DOT set. nfs_lookup_revalidate will see that the parent directory has changed and will try to reverify the dentry by redoing a LOOKUP. That of course fails, so the lookup code returns ESTALE. The problem here is that d_revalidate is really a bad fit for this case. What we really want to know at this point is whether the inode is still good or not, but we don't really care what name it goes by or whether the dcache is still valid. Add a new d_op->d_weak_revalidate operation and have complete_walk call that instead of d_revalidate. The intent there is to allow for a "weaker" d_revalidate that just checks to see whether the inode is still good. This is also gives us an opportunity to kill off the FS_REVAL_DOT special casing. [AV: changed method name, added note in porting, fixed confusion re having it possibly called from RCU mode (it won't be)] Cc: NeilBrown <neilb@suse.de> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22lookup_slow: get rid of name argumentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22lookup_fast: get rid of name argumentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22get rid of name and type arguments of walk_component()Al Viro
... always can be found in nameidata now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22link_path_walk(): move assignments to nd->last/nd->last_type upAl Viro
... and clean the main loop a bit Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22propagate error from get_empty_filp() to its callersAl Viro
Based on parts from Anatol's patch (the rest is the next commit). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: fix renameat to retry on ESTALE errorsJeff Layton
...as always, rename is the messiest of the bunch. We have to track whether to retry or not via a separate flag since the error handling is already quite complex. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make do_unlinkat retry once on ESTALE errorsJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make do_rmdir retry once on ESTALE errorsJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: add a flags argument to user_path_parentJeff Layton
...so we can pass in LOOKUP_REVAL. For now, nothing does yet. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: fix linkat to retry once on ESTALE errorsJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: fix symlinkat to retry on ESTALE errorsJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: fix mkdirat to retry once on an ESTALE errorJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: fix mknodat to retry on ESTALE errorsJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: turn is_dir argument to kern_path_create into a lookup_flags argJeff Layton
Where we can pass in LOOKUP_DIRECTORY or LOOKUP_REVAL. Any other flags passed in here are currently ignored. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: remove DCACHE_NEED_LOOKUPJeff Layton
The code that relied on that flag was ripped out of btrfs quite some time ago, and never added back. Josef indicated that he was going to take a different approach to the problem in btrfs, and that we could just eliminate this flag. Cc: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20path_init(): make -ENOTDIR failure exits consistentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: remove unneeded permission check from path_initJeff Layton
When path_init is called with a valid dfd, that code checks permissions on the open directory fd and returns an error if the check fails. This permission check is redundant, however. Both callers of path_init immediately call link_path_walk afterward. The first thing that link_path_walk does for pathnames that do not consist only of slashes is to check for exec permissions at the starting point of the path walk. And this check in path_init() is on the path taken only when *name != '/' && *name != '\0'. In most cases, these checks are very quick, but when the dfd is for a file on a NFS mount with the actimeo=0, each permission check goes out onto the wire. The result is 2 identical ACCESS calls. Given that these codepaths are fairly "hot", I think it makes sense to eliminate the permission check in path_init and simply assume that the caller will eventually check the permissions before proceeding. Reported-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-29lookup_one_len: don't accept . and ..Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-26VFS: don't do protected {sym,hard}links by defaultLinus Torvalds
In commit 800179c9b8a1 ("This adds symlink and hardlink restrictions to the Linux VFS"), the new link protections were enabled by default, in the hope that no actual application would care, despite it being technically against legacy UNIX (and documented POSIX) behavior. However, it does turn out to break some applications. It's rare, and it's unfortunate, but it's unacceptable to break existing systems, so we'll have to default to legacy behavior. In particular, it has broken the way AFD distributes files, see http://www.dwd.de/AFD/ along with some legacy scripts. Distributions can end up setting this at initrd time or in system scripts: if you have security problems due to link attacks during your early boot sequence, you have bigger problems than some kernel sysctl setting. Do: echo 1 > /proc/sys/fs/protected_symlinks echo 1 > /proc/sys/fs/protected_hardlinks to re-enable the link protections. Alternatively, we may at some point introduce a kernel config option that sets these kinds of "more secure but not traditional" behavioural options automatically. Reported-by: Nick Bowler <nbowler@elliptictech.com> Reported-by: Holger Kiehl <Holger.Kiehl@dwd.de> Cc: Kees Cook <keescook@chromium.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org # v3.6 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-12vfs: embed struct filename inside of names_cache allocation if possibleJeff Layton
In the common case where a name is much smaller than PATH_MAX, an extra allocation for struct filename is unnecessary. Before allocating a separate one, try to embed the struct filename inside the buffer first. If it turns out that that's not long enough, then fall back to allocating a separate struct filename and redoing the copy. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12audit: make audit_inode take struct filenameJeff Layton
Keep a pointer to the audit_names "slot" in struct filename. Have all of the audit_inode callers pass a struct filename ponter to audit_inode instead of a string pointer. If the aname field is already populated, then we can skip walking the list altogether and just use it directly. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12vfs: make path_openat take a struct filename pointerJeff Layton
...and fix up the callers. For do_file_open_root, just declare a struct filename on the stack and fill out the .name field. For do_filp_open, make it also take a struct filename pointer, and fix up its callers to call it appropriately. For filp_open, add a variant that takes a struct filename pointer and turn filp_open into a wrapper around it. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12vfs: turn do_path_lookup into wrapper around struct filename variantJeff Layton
...and make the user_path callers use that variant instead. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12audit: allow audit code to satisfy getname requests from its names_listJeff Layton
Currently, if we call getname() on a userland string more than once, we'll get multiple copies of the string and multiple audit_names records. Add a function that will allow the audit_names code to satisfy getname requests using info from the audit_names list, avoiding a new allocation and audit_names records. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12vfs: define struct filename and have getname() return itJeff Layton
getname() is intended to copy pathname strings from userspace into a kernel buffer. The result is just a string in kernel space. It would however be quite helpful to be able to attach some ancillary info to the string. For instance, we could attach some audit-related info to reduce the amount of audit-related processing needed. When auditing is enabled, we could also call getname() on the string more than once and not need to recopy it from userspace. This patchset converts the getname()/putname() interfaces to return a struct instead of a string. For now, the struct just tracks the string in kernel space and the original userland pointer for it. Later, we'll add other information to the struct as it becomes convenient. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12vfs: unexport getname and putname symbolsJeff Layton
I see no callers in module code. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12audit: overhaul __audit_inode_child to accomodate retryingJeff Layton
In order to accomodate retrying path-based syscalls, we need to add a new "type" argument to audit_inode_child. This will tell us whether we're looking for a child entry that represents a create or a delete. If we find a parent, don't automatically assume that we need to create a new entry. Instead, use the information we have to try to find an existing entry first. Update it if one is found and create a new one if not. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12audit: set the name_len in audit_inode for parent lookupsJeff Layton
Currently, this gets set mostly by happenstance when we call into audit_inode_child. While that might be a little more efficient, it seems wrong. If the syscall ends up failing before audit_inode_child ever gets called, then you'll have an audit_names record that shows the full path but has the parent inode info attached. Fix this by passing in a parent flag when we call audit_inode that gets set to the value of LOOKUP_PARENT. We can then fix up the pathname for the audit entry correctly from the get-go. While we're at it, clean up the no-op macro for audit_inode in the !CONFIG_AUDITSYSCALL case. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12audit: reverse arguments to audit_inode_childJeff Layton
Most of the callers get called with an inode and dentry in the reverse order. The compiler then has to reshuffle the arg registers and/or stack in order to pass them on to audit_inode_child. Reverse those arguments for a micro-optimization. Reported-by: Eric Paris <eparis@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12audit: remove unnecessary NULL ptr checks from do_path_lookupJeff Layton
As best I can tell, whenever retval == 0, nd->path.dentry and nd->inode are also non-NULL. Eliminate those checks and the superfluous audit_context check. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-11vfs: bogus warnings in fs/namei.cArnd Bergmann
The follow_link() function always initializes its *p argument, or returns an error, but when building with 'gcc -s', the compiler gets confused by the __always_inline attribute to the function and can no longer detect where the cookie was initialized. The solution is to always initialize the pointer from follow_link, even in the error path. When building with -O2, this has zero impact on generated code and adds a single instruction in the error path for a -Os build on ARM. Without this patch, building with gcc-4.6 through gcc-4.8 and CONFIG_CC_OPTIMIZE_FOR_SIZE results in: fs/namei.c: In function 'link_path_walk': fs/namei.c:649:24: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized] fs/namei.c:1544:9: note: 'cookie' was declared here fs/namei.c: In function 'path_lookupat': fs/namei.c:649:24: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized] fs/namei.c:1934:10: note: 'cookie' was declared here fs/namei.c: In function 'path_openat': fs/namei.c:649:24: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized] fs/namei.c:2899:9: note: 'cookie' was declared here Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-09fs: prevent use after free in auditing when symlink following was deniedSasha Levin
Commit "fs: add link restriction audit reporting" has added auditing of failed attempts to follow symlinks. Unfortunately, the auditing was being done after the struct path structure was released earlier. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs update from Al Viro: - big one - consolidation of descriptor-related logics; almost all of that is moved to fs/file.c (BTW, I'm seriously tempted to rename the result to fd.c. As it is, we have a situation when file_table.c is about handling of struct file and file.c is about handling of descriptor tables; the reasons are historical - file_table.c used to be about a static array of struct file we used to have way back). A lot of stray ends got cleaned up and converted to saner primitives, disgusting mess in android/binder.c is still disgusting, but at least doesn't poke so much in descriptor table guts anymore. A bunch of relatively minor races got fixed in process, plus an ext4 struct file leak. - related thing - fget_light() partially unuglified; see fdget() in there (and yes, it generates the code as good as we used to have). - also related - bits of Cyrill's procfs stuff that got entangled into that work; _not_ all of it, just the initial move to fs/proc/fd.c and switch of fdinfo to seq_file. - Alex's fs/coredump.c spiltoff - the same story, had been easier to take that commit than mess with conflicts. The rest is a separate pile, this was just a mechanical code movement. - a few misc patches all over the place. Not all for this cycle, there'll be more (and quite a few currently sit in akpm's tree)." Fix up trivial conflicts in the android binder driver, and some fairly simple conflicts due to two different changes to the sock_alloc_file() interface ("take descriptor handling from sock_alloc_file() to callers" vs "net: Providing protocol type via system.sockprotoname xattr of /proc/PID/fd entries" adding a dentry name to the socket) * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits) MAX_LFS_FILESIZE should be a loff_t compat: fs: Generic compat_sys_sendfile implementation fs: push rcu_barrier() from deactivate_locked_super() to filesystems btrfs: reada_extent doesn't need kref for refcount coredump: move core dump functionality into its own file coredump: prevent double-free on an error path in core dumper usb/gadget: fix misannotations fcntl: fix misannotations ceph: don't abuse d_delete() on failure exits hypfs: ->d_parent is never NULL or negative vfs: delete surplus inode NULL check switch simple cases of fget_light to fdget new helpers: fdget()/fdput() switch o2hb_region_dev_write() to fget_light() proc_map_files_readdir(): don't bother with grabbing files make get_file() return its argument vhost_set_vring(): turn pollstart/pollstop into bool switch prctl_set_mm_exe_file() to fget_light() switch xfs_find_handle() to fget_light() switch xfs_swapext() to fget_light() ...
2012-10-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace changes from Eric Biederman: "This is a mostly modest set of changes to enable basic user namespace support. This allows the code to code to compile with user namespaces enabled and removes the assumption there is only the initial user namespace. Everything is converted except for the most complex of the filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs, nfs, ocfs2 and xfs as those patches need a bit more review. The strategy is to push kuid_t and kgid_t values are far down into subsystems and filesystems as reasonable. Leaving the make_kuid and from_kuid operations to happen at the edge of userspace, as the values come off the disk, and as the values come in from the network. Letting compile type incompatible compile errors (present when user namespaces are enabled) guide me to find the issues. The most tricky areas have been the places where we had an implicit union of uid and gid values and were storing them in an unsigned int. Those places were converted into explicit unions. I made certain to handle those places with simple trivial patches. Out of that work I discovered we have generic interfaces for storing quota by projid. I had never heard of the project identifiers before. Adding full user namespace support for project identifiers accounts for most of the code size growth in my git tree. Ultimately there will be work to relax privlige checks from "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing root in a user names to do those things that today we only forbid to non-root users because it will confuse suid root applications. While I was pushing kuid_t and kgid_t changes deep into the audit code I made a few other cleanups. I capitalized on the fact we process netlink messages in the context of the message sender. I removed usage of NETLINK_CRED, and started directly using current->tty. Some of these patches have also made it into maintainer trees, with no problems from identical code from different trees showing up in linux-next. After reading through all of this code I feel like I might be able to win a game of kernel trivial pursuit." Fix up some fairly trivial conflicts in netfilter uid/git logging code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits) userns: Convert the ufs filesystem to use kuid/kgid where appropriate userns: Convert the udf filesystem to use kuid/kgid where appropriate userns: Convert ubifs to use kuid/kgid userns: Convert squashfs to use kuid/kgid where appropriate userns: Convert reiserfs to use kuid and kgid where appropriate userns: Convert jfs to use kuid/kgid where appropriate userns: Convert jffs2 to use kuid and kgid where appropriate userns: Convert hpfs to use kuid and kgid where appropriate userns: Convert btrfs to use kuid/kgid where appropriate userns: Convert bfs to use kuid/kgid where appropriate userns: Convert affs to use kuid/kgid wherwe appropriate userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids userns: On ia64 deal with current_uid and current_gid being kuid and kgid userns: On ppc convert current_uid from a kuid before printing. userns: Convert s390 getting uid and gid system calls to use kuid and kgid userns: Convert s390 hypfs to use kuid and kgid where appropriate userns: Convert binder ipc to use kuids userns: Teach security_path_chown to take kuids and kgids userns: Add user namespace support to IMA userns: Convert EVM to deal with kuids and kgids in it's hmac computation ...
2012-09-26switch simple cases of fget_light to fdgetAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26namei.c: fix BS commentAl Viro
get_write_access() is needed for nfsd, not binfmt_aout (the latter has no business doing anything of that kind, of course) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>