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2016-01-12Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "All kinds of stuff. That probably should've been 5 or 6 separate branches, but by the time I'd realized how large and mixed that bag had become it had been too close to -final to play with rebasing. Some fs/namei.c cleanups there, memdup_user_nul() introduction and switching open-coded instances, burying long-dead code, whack-a-mole of various kinds, several new helpers for ->llseek(), assorted cleanups and fixes from various people, etc. One piece probably deserves special mention - Neil's lookup_one_len_unlocked(). Similar to lookup_one_len(), but gets called without ->i_mutex and tries to avoid ever taking it. That, of course, means that it's not useful for any directory modifications, but things like getting inode attributes in nfds readdirplus are fine with that. I really should've asked for moratorium on lookup-related changes this cycle, but since I hadn't done that early enough... I *am* asking for that for the coming cycle, though - I'm going to try and get conversion of i_mutex to rwsem with ->lookup() done under lock taken shared. There will be a patch closer to the end of the window, along the lines of the one Linus had posted last May - mechanical conversion of ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/ inode_is_locked()/inode_lock_nested(). To quote Linus back then: ----- | This is an automated patch using | | sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/' | sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/' | sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[ ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/' | sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/' | sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/' | | with a very few manual fixups ----- I'm going to send that once the ->i_mutex-affecting stuff in -next gets mostly merged (or when Linus says he's about to stop taking merges)" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) nfsd: don't hold i_mutex over userspace upcalls fs:affs:Replace time_t with time64_t fs/9p: use fscache mutex rather than spinlock proc: add a reschedule point in proc_readfd_common() logfs: constify logfs_block_ops structures fcntl: allow to set O_DIRECT flag on pipe fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE fs: xattr: Use kvfree() [s390] page_to_phys() always returns a multiple of PAGE_SIZE nbd: use ->compat_ioctl() fs: use block_device name vsprintf helper lib/vsprintf: add %*pg format specifier fs: use gendisk->disk_name where possible poll: plug an unused argument to do_poll amdkfd: don't open-code memdup_user() cdrom: don't open-code memdup_user() rsxx: don't open-code memdup_user() mtip32xx: don't open-code memdup_user() [um] mconsole: don't open-code memdup_user_nul() [um] hostaudio: don't open-code memdup_user() ...
2016-01-09fs: xattr: Use kvfree()Richard Weinberger
... instead of open coding it. Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-13xattr handlers: Simplify list operationAndreas Gruenbacher
Change the list operation to only return whether or not an attribute should be listed. Copying the attribute names into the buffer is moved to the callers. Since the result only depends on the dentry and not on the attribute name, we do not pass the attribute name to list operations. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-13nfs: Move call to security_inode_listsecurity into nfs_listxattrAndreas Gruenbacher
Add a nfs_listxattr operation. Move the call to security_inode_listsecurity from list operation of the "security.*" xattr handler to nfs_listxattr. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Cc: Anna Schumaker <anna.schumaker@netapp.com> Cc: linux-nfs@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06tmpfs: listxattr should include POSIX ACL xattrsAndreas Gruenbacher
When a file on tmpfs has an ACL or a Default ACL, listxattr should include the corresponding xattr name. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: linux-mm@kvack.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06tmpfs: Use xattr handler infrastructureAndreas Gruenbacher
Use the VFS xattr handler infrastructure and get rid of similar code in the filesystem. For implementing shmem_xattr_handler_set, we need a version of simple_xattr_set which removes the attribute when value is NULL. Use this to implement kernfs_iop_removexattr as well. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: linux-mm@kvack.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06vfs: Distinguish between full xattr names and proper prefixesAndreas Gruenbacher
Add an additional "name" field to struct xattr_handler. When the name is set, the handler matches attributes with exactly that name. When the prefix is set instead, the handler matches attributes with the given prefix and with a non-empty suffix. This patch should avoid bugs like the one fixed in commit c361016a in the future. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06vfs: Remove vfs_xattr_cmpAndreas Gruenbacher
This function was only briefly used in security/integrity/evm, between commits 66dbc325 and 15647eb3. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-11-139p: xattr simplificationsAndreas Gruenbacher
Now that the xattr handler is passed to the xattr handler operations, we can use the same get and set operations for the user, trusted, and security xattr namespaces. In those namespaces, we can access the full attribute name by "reattaching" the name prefix the vfs has skipped for us. Add a xattr_full_name helper to make this obvious in the code. For the "system.posix_acl_access" and "system.posix_acl_default" attributes, handler->prefix is the full attribute name; the suffix is the empty string. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Cc: v9fs-developer@lists.sourceforge.net Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-11-13xattr handlers: Pass handler to operations instead of flagsAndreas Gruenbacher
The xattr_handler operations are currently all passed a file system specific flags value which the operations can use to disambiguate between different handlers; some file systems use that to distinguish the xattr namespace, for example. In some oprations, it would be useful to also have access to the handler prefix. To allow that, pass a pointer to the handler to operations instead of the flags value alone. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-21evm: fix potential race when removing xattrsDmitry Kasatkin
EVM needs to be atomically updated when removing xattrs. Otherwise concurrent EVM verification may fail in between. This patch fixes by moving i_mutex unlocking after calling EVM hook. fsnotify_xattr() is also now called while locked the same way as it is done in __vfs_setxattr_noperm. Changelog: - remove unused 'inode' variable. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-19new helper: audit_file()Al Viro
... for situations when we don't have any candidate in pathnames - basically, in descriptor-based syscalls. [Folded the build fix for !CONFIG_AUDITSYSCALL configs from Chen Gang] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-12vfs: Deduplicate code shared by xattr system calls operating on pathsEric Biggers
The following pairs of system calls dealing with extended attributes only differ in their behavior on whether the symbolic link is followed (when the named file is a symbolic link): - setxattr() and lsetxattr() - getxattr() and lgetxattr() - listxattr() and llistxattr() - removexattr() and lremovexattr() Despite this, the implementations all had duplicated code, so this commit redirects each of the above pairs of system calls to a corresponding function to which different lookup flags (LOOKUP_FOLLOW or 0) are passed. For me this reduced the stripped size of xattr.o from 8824 to 8248 bytes. Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-07-23simple_xattr: permit 0-size extended attributesHugh Dickins
If a filesystem uses simple_xattr to support user extended attributes, LTP setxattr01 and xfstests generic/062 fail with "Cannot allocate memory": simple_xattr_alloc()'s wrap-around test mistakenly excludes values of zero size. Fix that off-by-one (but apparently no filesystem needs them yet). Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jeff Layton <jlayton@poochiereds.net> Cc: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-20vfs: make lremovexattr retry once on ESTALE errorJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make removexattr retry once on ESTALEJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make llistxattr retry once on ESTALE errorJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make listxattr retry once on ESTALE errorJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make lgetxattr retry once on ESTALEJeff Layton
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20vfs: make getxattr 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: allow lsetxattr() 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: allow setxattr 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>
2012-10-18fs, xattr: fix bug when removing a name not in xattr listDavid Rientjes
Commit 38f38657444d ("xattr: extract simple_xattr code from tmpfs") moved some code from tmpfs but introduced a subtle bug along the way. If the name passed to simple_xattr_remove() does not exist in the list of xattrs, then it is possible to call kfree(new_xattr) when new_xattr is actually initialized to itself on the stack via uninitialized_var(). This causes a BUG() since the memory was not allocated via the slab allocator and was not bypassed through to the page allocator because it was too large. Initialize the local variable to NULL so the kfree() never takes place. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Hugh Dickins <hughd@google.com> Acked-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
2012-10-02Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Highlights: - Integrity: add local fs integrity verification to detect offline attacks - Integrity: add digital signature verification - Simple stacking of Yama with other LSMs (per LSS discussions) - IBM vTPM support on ppc64 - Add new driver for Infineon I2C TIS TPM - Smack: add rule revocation for subject labels" Fixed conflicts with the user namespace support in kernel/auditsc.c and security/integrity/ima/ima_policy.c. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (39 commits) Documentation: Update git repository URL for Smack userland tools ima: change flags container data type Smack: setprocattr memory leak fix Smack: implement revoking all rules for a subject label Smack: remove task_wait() hook. ima: audit log hashes ima: generic IMA action flag handling ima: rename ima_must_appraise_or_measure audit: export audit_log_task_info tpm: fix tpm_acpi sparse warning on different address spaces samples/seccomp: fix 31 bit build on s390 ima: digital signature verification support ima: add support for different security.ima data types ima: add ima_inode_setxattr/removexattr function and calls ima: add inode_post_setattr call ima: replace iint spinblock with rwlock/read_lock ima: allocating iint improvements ima: add appraise action keywords and default rules ima: integrity appraisal extension vfs: move ima_file_free before releasing the file ...
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>
2012-09-18userns: Convert vfs posix_acl support to use kuids and kgidsEric W. Biederman
- In setxattr if we are setting a posix acl convert uids and gids from the current user namespace into the initial user namespace, before the xattrs are passed to the underlying filesystem. Untranslatable uids and gids are represented as -1 which posix_acl_from_xattr will represent as INVALID_UID or INVALID_GID. posix_acl_valid will fail if an acl from userspace has any INVALID_UID or INVALID_GID values. In net this guarantees that untranslatable posix acls will not be stored by filesystems. - In getxattr if we are reading a posix acl convert uids and gids from the initial user namespace into the current user namespace. Uids and gids that can not be tranlsated into the current user namespace will be represented as -1. - Replace e_id in struct posix_acl_entry with an anymouns union of e_uid and e_gid. For the short term retain the e_id field until all of the users are converted. - Don't set struct posix_acl.e_id in the cases where the acl type does not use e_id. Greatly reducing the use of ACL_UNDEFINED_ID. - Rework the ordering checks in posix_acl_valid so that I use kuid_t and kgid_t types throughout the code, and so that I don't need arithmetic on uid and gid types. Cc: Theodore Tso <tytso@mit.edu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-13xattr: mark variable as uninitialized to make both gcc and smatch happyAristeu Rozanski
new_xattr in __simple_xattr_set() is only initialized with a valid pointer if value is not NULL, which only happens if this function is called directly with the intention to remove an existing extended attribute. Even being safe to be this way, smatch warns about possible NULL dereference. Dan Carpenter suggested using uninitialized_var() which will make both gcc and smatch happy. Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-09-13fs: add missing documentation to simple_xattr functionsAristeu Rozanski
v2: add function documentation instead of adding a separate file under Documentation/ tj: Updated comment a bit and rolled in Randy's suggestions. Cc: Li Zefan <lizefan@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lennart Poettering <lpoetter@redhat.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-09-07vfs: extend vfs_removexattr lockingMimi Zohar
This patch takes the i_mutex lock before security_inode_removexattr(), instead of after, in preparation of calling ima_inode_removexattr(). Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
2012-08-24xattr: extract simple_xattr code from tmpfsAristeu Rozanski
Extract in-memory xattr APIs from tmpfs. Will be used by cgroup. $ size vmlinux.o text data bss dec hex filename 4658782 880729 5195032 10734543 a3cbcf vmlinux.o $ size vmlinux.o text data bss dec hex filename 4658957 880729 5195032 10734718 a3cc7e vmlinux.o v7: - checkpatch warnings fixed - Implement the changes requested by Hugh Dickins: - make simple_xattrs_init and simple_xattrs_free inline - get rid of locking and list reinitialization in simple_xattrs_free, they're not needed v6: - no changes v5: - no changes v4: - move simple_xattrs_free() to fs/xattr.c v3: - in kmem_xattrs_free(), reinitialize the list - use simple_xattr_* prefix - introduce simple_xattr_add() to prevent direct list usage Original-patch-by: Li Zefan <lizefan@huawei.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lennart Poettering <lpoetter@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Aristeu Rozanski <aris@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-07-30fs/xattr.c:getxattr(): improve handling of allocation failuresSasha Levin
This allocation can be as large as 64k. - Add __GFP_NOWARN so the falied kmalloc() is silent - Fall back to vmalloc() if the kmalloc() failed Signed-off-by: Sasha Levin <levinsasha928@gmail.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>
2012-05-29switch xattr syscalls to fget_light/fput_lightAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-04-05fs/xattr.c:setxattr(): improve handling of allocation failuresAndrew Morton
This allocation can be as large as 64k. - Add __GFP_NOWARN so the a falied kmalloc() is silent - Fall back to vmalloc() if the kmalloc() failed Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: David Rientjes <rientjes@google.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>
2012-04-05fs/xattr.c:listxattr(): fall back to vmalloc() if kmalloc() failedAndrew Morton
This allocation can be as large as 64k. As David points out, "falling back to vmalloc here is much better solution than failing to retreive the attribute - it will work no matter how fragmented memory gets. That means we don't get incomplete backups occurring after days or months of uptime and successful backups". Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: David Rientjes <rientjes@google.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>
2012-04-05fs/xattr.c: suppress page allocation failure warnings from sys_listxattr()Dave Jones
This size is user controllable, up to a maximum of XATTR_LIST_MAX (64k). So it's trivial for someone to trigger a stream of order:4 page allocation errors. Signed-off-by: Dave Jones <davej@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Chinner <david@fromorbit.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-28fs: reduce the use of module.h wherever possiblePaul Gortmaker
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
2011-07-18evm: evm_inode_post_removexattrMimi Zohar
When an EVM protected extended attribute is removed, update 'security.evm'. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
2011-07-18xattr: define vfs_getxattr_alloc and vfs_xattr_cmpMimi Zohar
vfs_getxattr_alloc() and vfs_xattr_cmp() are two new kernel xattr helper functions. vfs_getxattr_alloc() first allocates memory for the requested xattr and then retrieves it. vfs_xattr_cmp() compares a given value with the contents of an extended attribute. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
2011-05-28Cache xattr security drop check for write v2Andi Kleen
Some recent benchmarking on btrfs showed that a major scaling bottleneck on large systems on btrfs is currently the xattr lookup on every write. Why xattr lookup on every write I hear you ask? write wants to drop suid and security related xattrs that could set o capabilities for executables. To do that it currently looks up security.capability on EVERY write (even for non executables) to decide whether to drop it or not. In btrfs this causes an additional tree walk, hitting some per file system locks and quite bad scalability. In a simple read workload on a 8S system I saw over 90% CPU time in spinlocks related to that. Chris Mason tells me this is also a problem in ext4, where it hits the global mbcache lock. This patch adds a simple per inode to avoid this problem. We only do the lookup once per file and then if there is no xattr cache the decision. All xattr changes clear the flag. I also used the same flag to avoid the suid check, although that one is pretty cheap. A file system can also set this flag when it creates the inode, if it has a cheap way to do so. This is done for some common file systems in followon patches. With this patch a major part of the lock contention disappears for btrfs. Some testing on smaller systems didn't show significant performance changes, but at least it helps the larger systems and is generally more efficient. v2: Rename is_sgid. add file system helper. Cc: chris.mason@oracle.com Cc: josef@redhat.com Cc: viro@zeniv.linux.org.uk Cc: agruen@linbit.com Cc: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-27xattr: Fix error results for non-existent / invisible attributesAndreas Gruenbacher
Return -ENODATA when trying to read a user.* attribute which cannot exist: user space otherwise does not have a reasonable way to distinguish between non-existent and inaccessible attributes. Likewise, return -ENODATA when an unprivileged process tries to read a trusted.* attribute: to unprivileged processes, those attributes are invisible (listxattr() won't include them). Related to this bug report: https://bugzilla.redhat.com/660613 Signed-off-by: Andreas Gruenbacher <agruen@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-04-21vfs: Pass setxattr(2) flags properlyJan Kara
For some reason generic_setxattr() did not pass flags (XATTR_CREATE, XATTR_REPLACE) to the filesystem specific helper. This caused that setxattr(2) syscall just ignored these flags. Fix the bug by passing flags correctly. Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23userns: rename is_owner_or_cap to inode_owner_or_capableSerge E. Hallyn
And give it a kernel-doc comment. [akpm@linux-foundation.org: btrfs changed in linux-next] Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-21fs: xattr_handler table should be constStephen Hemminger
The entries in xattr handler table should be immutable (ie const) like other operation tables. Later patches convert common filesystems. Uncoverted filesystems will still work, but will generate a compiler warning. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16sanitize xattr handler prototypesChristoph Hellwig
Add a flags argument to struct xattr_handler and pass it to all xattr handler methods. This allows using the same methods for multiple handlers, e.g. for the ACL methods which perform exactly the same action for the access and default ACLs, just using a different underlying attribute. With a little more groundwork it'll also allow sharing the methods for the regular user/trusted/secure handlers in extN, ocfs2 and jffs2 like it's already done for xfs in this patch. Also change the inode argument to the handlers to a dentry to allow using the handlers mechnism for filesystems that require it later, e.g. cifs. [with GFS2 bits updated by Steven Whitehouse <swhiteho@redhat.com>] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jmorris@namei.org> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-10VFS: Factor out part of vfs_setxattr so it can be called from the SELinux ↵David P. Quigley
hook for inode_setsecctx. This factors out the part of the vfs_setxattr function that performs the setting of the xattr and its notification. This is needed so the SELinux implementation of inode_setsecctx can handle the setting of the xattr while maintaining the proper separation of layers. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
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>