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2012-02-19Wrap accesses to the fd_sets in struct fdtableDavid Howells
Wrap accesses to the fd_sets in struct fdtable (for recording open files and close-on-exec flags) so that we can move away from using fd_sets since we abuse the fd_set structs by not allocating the full-sized structure under normal circumstances and by non-core code looking at the internals of the fd_sets. The first abuse means that use of FD_ZERO() on these fd_sets is not permitted, since that cannot be told about their abnormal lengths. This introduces six wrapper functions for setting, clearing and testing close-on-exec flags and fd-is-open flags: void __set_close_on_exec(int fd, struct fdtable *fdt); void __clear_close_on_exec(int fd, struct fdtable *fdt); bool close_on_exec(int fd, const struct fdtable *fdt); void __set_open_fd(int fd, struct fdtable *fdt); void __clear_open_fd(int fd, struct fdtable *fdt); bool fd_is_open(int fd, const struct fdtable *fdt); Note that I've prepended '__' to the names of the set/clear functions because they require the caller to hold a lock to use them. Note also that I haven't added wrappers for looking behind the scenes at the the array. Possibly that should exist too. Signed-off-by: David Howells <dhowells@redhat.com> Link: http://lkml.kernel.org/r/20120216174942.23314.1364.stgit@warthog.procyon.org.uk Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06switch security_path_chmod() to struct path *Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03switch open and mkdir syscalls to umode_tAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03switch sys_chmod()/sys_fchmod()/sys_fchmodat() to umode_tAl Viro
SYSCALLx magic should take care of things, according to Linus... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: mnt_drop_write_file()Al Viro
new helper (wrapper around mnt_drop_write()) to be used in pair with mnt_want_write_file(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-10-28leases: fix write-open/read-lease raceJ. Bruce Fields
In setlease, we use i_writecount to decide whether we can give out a read lease. In open, we break leases before incrementing i_writecount. There is therefore a window between the break lease and the i_writecount increment when setlease could add a new read lease. This would leave us with a simultaneous write open and read lease, which shouldn't happen. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-07-26merge fchmod() and fchmodat() guts, kill ancient broken kludgeAl Viro
The kludge in question is undocumented and doesn't work for 32bit binaries on amd64, sparc64 and s390. Passing (mode_t)-1 as mode had (since 0.99.14v and contrary to behaviour of any other Unix, prescriptions of POSIX, SuS and our own manpages) was kinda-sorta no-op. Note that any software relying on that (and looking for examples shows none) would be visibly broken on sparc64, where practically all userland is built 32bit. No such complaints noticed... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-22vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filpKonstantin Khlebnikov
Replace unclear (struct dentry *) to (struct file *) typecast with ERR_CAST() macro. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-21fs: Use BUG_ON(!mnt) at dentry_open().Tetsuo Handa
dentry_open() requires callers to pass a valid vfsmount. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-16Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (33 commits) AppArmor: kill unused macros in lsm.c AppArmor: cleanup generated files correctly KEYS: Add an iovec version of KEYCTL_INSTANTIATE KEYS: Add a new keyctl op to reject a key with a specified error code KEYS: Add a key type op to permit the key description to be vetted KEYS: Add an RCU payload dereference macro AppArmor: Cleanup make file to remove cruft and make it easier to read SELinux: implement the new sb_remount LSM hook LSM: Pass -o remount options to the LSM SELinux: Compute SID for the newly created socket SELinux: Socket retains creator role and MLS attribute SELinux: Auto-generate security_is_socket_class TOMOYO: Fix memory leak upon file open. Revert "selinux: simplify ioctl checking" selinux: drop unused packet flow permissions selinux: Fix packet forwarding checks on postrouting selinux: Fix wrong checks for selinux_policycap_netpeer selinux: Fix check for xfrm selinux context algorithm ima: remove unnecessary call to ima_must_measure IMA: remove IMA imbalance checking ...
2011-03-16Merge branch 'next' into for-linusJames Morris
2011-03-15readlinkat(), fchownat() and fstatat() with empty relative pathnamesAl Viro
For readlinkat() we simply allow empty pathname; it will fail unless we have dfd equal to O_PATH-opened symlink, so we are outside of POSIX scope here. For fchownat() and fstatat() we allow AT_EMPTY_PATH; let the caller explicitly ask for such behaviour. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-15New kind of open files - "location only".Al Viro
New flag for open(2) - O_PATH. Semantics: * pathname is resolved, but the file itself is _NOT_ opened as far as filesystem is concerned. * almost all operations on the resulting descriptors shall fail with -EBADF. Exceptions are: 1) operations on descriptors themselves (i.e. close(), dup(), dup2(), dup3(), fcntl(fd, F_DUPFD), fcntl(fd, F_DUPFD_CLOEXEC, ...), fcntl(fd, F_GETFD), fcntl(fd, F_SETFD, ...)) 2) fcntl(fd, F_GETFL), for a common non-destructive way to check if descriptor is open 3) "dfd" arguments of ...at(2) syscalls, i.e. the starting points of pathname resolution * closing such descriptor does *NOT* affect dnotify or posix locks. * permissions are checked as usual along the way to file; no permission checks are applied to the file itself. Of course, giving such thing to syscall will result in permission checks (at the moment it means checking that starting point of ....at() is a directory and caller has exec permissions on it). fget() and fget_light() return NULL on such descriptors; use of fget_raw() and fget_raw_light() is needed to get them. That protects existing code from dealing with those things. There are two things still missing (they come in the next commits): one is handling of symlinks (right now we refuse to open them that way; see the next commit for semantics related to those) and another is descriptor passing via SCM_RIGHTS datagrams. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-14open-style analog of vfs_path_lookup()Al Viro
new function: file_open_root(dentry, mnt, name, flags) opens the file vfs_path_lookup would arrive to. Note that name can be empty; in that case the usual requirement that dentry should be a directory is lifted. open-coded equivalents switched to it, may_open() got down exactly one caller and became static. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-14switch do_filp_open() to struct open_flagsAl Viro
take calculation of open_flags by open(2) arguments into new helper in fs/open.c, move filp_open() over there, have it and do_sys_open() use that helper, switch exec.c callers of do_filp_open() to explicit (and constant) struct open_flags. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-10Check for immutable/append flag in fallocate pathMarco Stornelli
In the fallocate path the kernel doesn't check for the immutable/append flag. It's possible to have a race condition in this scenario: an application open a file in read/write and it does something, meanwhile root set the immutable flag on the file, the application at that point can call fallocate with success. In addition, we don't allow to do any unreserve operation on an append only file but only the reserve one. Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-08Merge branch 'master'; commit 'v2.6.38-rc7' into nextJames Morris
2011-02-11Fix possible filp_cachep memory corruptionLinus Torvalds
In commit 31e6b01f4183 ("fs: rcu-walk for path lookup") we started doing path lookup using RCU, which then falls back to a careful non-RCU lookup in case of problems (LOOKUP_REVAL). So do_filp_open() has this "re-do the lookup carefully" looping case. However, that means that we must not release the open-intent file data if we are going to loop around and use it once more! Fix this by moving the release of the open-intent data to the function that allocates it (do_filp_open() itself) rather than the helper functions that can get called multiple times (finish_open() and do_last()). This makes the logic for the lifetime of that field much more obvious, and avoids the possible double free. Reported-by: J. R. Okajima <hooanon05@yahoo.co.jp> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-10IMA: maintain i_readcount in the VFS layerMimi Zohar
ima_counts_get() updated the readcount and invalidated the PCR, as necessary. Only update the i_readcount in the VFS layer. Move the PCR invalidation checks to ima_file_check(), where it belongs. Maintaining the i_readcount in the VFS layer, will allow other subsystems to use i_readcount. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Eric Paris <eparis@redhat.com>
2011-01-17fallocate should be a file operationChristoph Hellwig
Currently all filesystems except XFS implement fallocate asynchronously, while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC I/O we really want our allocation on disk, especially for the !KEEP_SIZE case where we actually grow the file with user-visible zeroes. On the other hand always commiting the transaction is a bad idea for fast-path uses of fallocate like for example in recent Samba versions. Given that block allocation is a data plane operation anyway change it from an inode operation to a file operation so that we have the file structure available that lets us check for O_SYNC. This also includes moving the code around for a few of the filesystems, and remove the already unnedded S_ISDIR checks given that we only wire up fallocate for regular files. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12fs: add hole punching to fallocateJosef Bacik
Hole punching has already been implemented by XFS and OCFS2, and has the potential to be implemented on both BTRFS and EXT4 so we need a generic way to get to this feature. The simplest way in my mind is to add FALLOC_FL_PUNCH_HOLE to fallocate() since it already looks like the normal fallocate() operation. I've tested this patch with XFS and BTRFS to make sure XFS did what it's supposed to do and that BTRFS failed like it was supposed to. Thank you, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29fix open/umount raceAl Viro
nameidata_to_filp() drops nd->path or transfers it to opened file. In the former case it's a Bad Idea(tm) to do mnt_drop_write() on nd->path.mnt, since we might race with umount and vfsmount in question might be gone already. Fix: don't drop it, then... IOW, have nameidata_to_filp() grab nd->path in case it transfers it to file and do path_drop() in callers. After they are through with accessing nd->path... Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-18fs: cleanup files_lock lockingNick Piggin
fs: cleanup files_lock locking Lock tty_files with a new spinlock, tty_files_lock; provide helpers to manipulate the per-sb files list; unexport the files_lock spinlock. Cc: linux-kernel@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-11vfs: clarify that nonseekable_open() will never failDmitry Torokhov
Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: John Kacur <jkacur@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-10Merge branch 'for-linus' of git://git.infradead.org/users/eparis/notifyLinus Torvalds
* 'for-linus' of git://git.infradead.org/users/eparis/notify: (132 commits) fanotify: use both marks when possible fsnotify: pass both the vfsmount mark and inode mark fsnotify: walk the inode and vfsmount lists simultaneously fsnotify: rework ignored mark flushing fsnotify: remove global fsnotify groups lists fsnotify: remove group->mask fsnotify: remove the global masks fsnotify: cleanup should_send_event fanotify: use the mark in handler functions audit: use the mark in handler functions dnotify: use the mark in handler functions inotify: use the mark in handler functions fsnotify: send fsnotify_mark to groups in event handling functions fsnotify: Exchange list heads instead of moving elements fsnotify: srcu to protect read side of inode and vfsmount locks fsnotify: use an explicit flag to indicate fsnotify_destroy_mark has been called fsnotify: use _rcu functions for mark list traversal fsnotify: place marks on object in order of group memory address vfs/fsnotify: fsnotify_close can delay the final work in fput fsnotify: store struct file not struct path ... Fix up trivial delete/modify conflict in fs/notify/inotify/inotify.c.
2010-08-02vfs: re-introduce MAY_CHDIREric Paris
Currently MAY_ACCESS means that filesystems must check the permissions right then and not rely on cached results or the results of future operations on the object. This can be because of a call to sys_access() or because of a call to chdir() which needs to check search without relying on any future operations inside that dir. I plan to use MAY_ACCESS for other purposes in the security system, so I split the MAY_ACCESS and the MAY_CHDIR cases. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02LSM: Remove unused arguments from security_path_truncate().Tetsuo Handa
When commit be6d3e56a6b9b3a4ee44a0685e39e595073c6f0d "introduce new LSM hooks where vfsmount is available." was proposed, regarding security_path_truncate(), only "struct file *" argument (which AppArmor wanted to use) was removed. But length and time_attrs arguments are not used by TOMOYO nor AppArmor. Thus, let's remove these arguments. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Nick Piggin <npiggin@suse.de> Signed-off-by: James Morris <jmorris@namei.org>
2010-07-28fsnotify: pass a file instead of an inode to open, read, and writeEric Paris
fanotify, the upcoming notification system actually needs a struct path so it can do opens in the context of listeners, and it needs a file so it can get f_flags from the original process. Close was the only operation that already was passing a struct file to the notification hook. This patch passes a file for access, modify, and open as well as they are easily available to these hooks. Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28inotify: remove inotify in kernel interfaceEric Paris
nothing uses inotify in the kernel, drop it! Signed-off-by: Eric Paris <eparis@redhat.com>
2010-05-21Take statfs variants to fs/statfs.cAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-05Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (33 commits) quota: stop using QUOTA_OK / NO_QUOTA dquot: cleanup dquot initialize routine dquot: move dquot initialization responsibility into the filesystem dquot: cleanup dquot drop routine dquot: move dquot drop responsibility into the filesystem dquot: cleanup dquot transfer routine dquot: move dquot transfer responsibility into the filesystem dquot: cleanup inode allocation / freeing routines dquot: cleanup space allocation / freeing routines ext3: add writepage sanity checks ext3: Truncate allocated blocks if direct IO write fails to update i_size quota: Properly invalidate caches even for filesystems with blocksize < pagesize quota: generalize quota transfer interface quota: sb_quota state flags cleanup jbd: Delay discarding buffers in journal_unmap_buffer ext3: quota_write cross block boundary behaviour quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota quota: split out compat_sys_quotactl support from quota.c quota: split out netlink notification support from quota.c quota: remove invalid optimization from quota_sync_all ... Fixed trivial conflicts in fs/namei.c and fs/ufs/inode.c
2010-03-05dquot: move dquot initialization responsibility into the filesystemChristoph Hellwig
Currently various places in the VFS call vfs_dq_init directly. This means we tie the quota code into the VFS. Get rid of that and make the filesystem responsible for the initialization. For most metadata operations this is a straight forward move into the methods, but for truncate and open it's a bit more complicated. For truncate we currently only call vfs_dq_init for the sys_truncate case because open already takes care of it for ftruncate and open(O_TRUNC) - the new code causes an additional vfs_dq_init for those which is harmless. For open the initialization is moved from do_filp_open into the open method, which means it happens slightly earlier now, and only for regular files. The latter is fine because we don't need to initialize it for operations on special files, and we already do it as part of the namespace operations for directories. Add a dquot_file_open helper that filesystems that support generic quotas can use to fill in ->open. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-03Switch may_open() and break_lease() to passing O_...Al Viro
... instead of mixing FMODE_ and O_ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-22Sanitize f_flags helpersAl Viro
* pull ACC_MODE to fs.h; we have several copies all over the place * nightmarish expression calculating f_mode by f_flags deserves a helper too (OPEN_FMODE(flags)) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-22Fix f_flags/f_mode in case of lookup_instantiate_filp() from open(pathname, 3)Al Viro
Just set f_flags when shoving struct file into nameidata; don't postpone that until __dentry_open(). do_filp_open() has correct value; lookup_instantiate_filp() doesn't - we lose the difference between O_RDWR and 3 by that point. We still set .intent.open.flags, so no fs code needs to be changed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16Untangling ima mess, part 2: deal with countersAl Viro
* do ima_get_count() in __dentry_open() * stop doing that in followups * move ima_path_check() to right after nameidata_to_filp() * don't bump counters on it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16fs: move get_empty_filp() deffinition to internal.hEric Paris
All users outside of fs/ of get_empty_filp() have been removed. This patch moves the definition from the include/ directory to internal.h so no new users crop up and removes the EXPORT_SYMBOL. I'd love to see open intents stop using it too, but that's a problem for another day and a smarter developer! Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-11-24LSM: Move security_path_chmod()/security_path_chown() to after mutex_lock().Tetsuo Handa
We should call security_path_chmod()/security_path_chown() after mutex_lock() in order to avoid races. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-10-12LSM: Add security_path_chroot().Tetsuo Handa
This patch allows pathname based LSM modules to check chroot() operations. This hook is used by TOMOYO. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2009-10-12LSM: Add security_path_chmod() and security_path_chown().Tetsuo Handa
This patch allows pathname based LSM modules to check chmod()/chown() operations. Since notify_change() does not receive "struct vfsmount *", we add security_path_chmod() and security_path_chown() to the caller of notify_change(). These hooks are used by TOMOYO. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-23fs: change sys_truncate length parameter typeHeiko Carstens
For this system call user space passes a signed long length parameter, while the kernel side takes an unsigned long parameter and converts it later to signed long again. This has led to bugs in compat wrappers see e.g. dd90bbd5 "powerpc: Add compat_sys_truncate". The s390 compat wrapper for this functions is broken as well since it also performs zero extension instead of sign extension for the length parameter. In addition if hpa comes up with an automated way of generating compat wrappers it would generate a wrong one here. So change the length parameter from unsigned long to long. Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-02CRED: Add some configurable debugging [try #6]David Howells
Add a config option (CONFIG_DEBUG_CREDENTIALS) to turn on some debug checking for credential management. The additional code keeps track of the number of pointers from task_structs to any given cred struct, and checks to see that this number never exceeds the usage count of the cred struct (which includes all references, not just those from task_structs). Furthermore, if SELinux is enabled, the code also checks that the security pointer in the cred struct is never seen to be invalid. This attempts to catch the bug whereby inode_has_perm() faults in an nfsd kernel thread on seeing cred->security be a NULL pointer (it appears that the credential struct has been previously released): http://www.kerneloops.org/oops.php?number=252883 Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-08-21vfs: allow file truncations when both suid and write permissions setAmerigo Wang
When suid is set and the non-owner user has write permission, any writing into this file should be allowed and suid should be removed after that. However, current kernel only allows writing without truncations, when we do truncations on that file, we get EPERM. This is a bug. Steps to reproduce this bug: % ls -l rootdir/file1 -rwsrwsrwx 1 root root 3 Jun 25 15:42 rootdir/file1 % echo h > rootdir/file1 zsh: operation not permitted: rootdir/file1 % ls -l rootdir/file1 -rwsrwsrwx 1 root root 3 Jun 25 15:42 rootdir/file1 % echo h >> rootdir/file1 % ls -l rootdir/file1 -rwxrwxrwx 1 root root 5 Jun 25 16:34 rootdir/file1 Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Eric Sandeen <esandeen@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Cc: Eugene Teo <eteo@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Christoph Hellwig <hch@lst.de> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: James Morris <jmorris@namei.org>
2009-06-24fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ↵Ankit Jain
ioctls This patch adds ioctls to vfs for compatibility with legacy XFS pre-allocation ioctls (XFS_IOC_*RESVP*). The implementation effectively invokes sys_fallocate for the new ioctls. Also handles the compat_ioctl case. Note: These legacy ioctls are also implemented by OCFS2. [AV: folded fixes from hch] Signed-off-by: Ankit Jain <me@ankitjain.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11fs: introduce mnt_clone_writenpiggin@suse.de
This patch speeds up lmbench lat_mmap test by about another 2% after the first patch. Before: avg = 462.286 std = 5.46106 After: avg = 453.12 std = 9.58257 (50 runs of each, stddev gives a reasonable confidence) It does this by introducing mnt_clone_write, which avoids some heavyweight operations of mnt_want_write if called on a vfsmount which we know already has a write count; and mnt_want_write_file, which can call mnt_clone_write if the file is open for write. After these two patches, mnt_want_write and mnt_drop_write go from 7% on the profile down to 1.3% (including mnt_clone_write). [AV: mnt_want_write_file() should take file alone and derive mnt from it; not only all callers have that form, but that's the only mnt about which we know that it's already held for write if file is opened for write] Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09Switch open_exec() and sys_uselib() to do_open_filp()Al Viro
... and make path_lookup_open() static Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31Get rid of indirect include of fs_struct.hAl Viro
Don't pull it in sched.h; very few files actually need it and those can include directly. sched.h itself only needs forward declaration of struct fs_struct; Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-26vfs: Use lowercase names of quota functionsJan Kara
Use lowercase names of quota functions instead of old uppercase ones. Signed-off-by: Jan Kara <jack@suse.cz> CC: Alexander Viro <viro@zeniv.linux.org.uk>
2009-01-14[CVE-2009-0029] System call wrappers part 30Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>