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2013-04-29ocfs2/dlm: remove redundant null pointer checkSachin Kamat
kfree on a NULL pointer is a no-op. Remove the redundant null pointer check. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Acked-by: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29ocfs2: fix NULL dereference for moving extentsDan Carpenter
We can't dereference "bg" before it has been assigned. GCC should have warned about this but "bg" was initialized to NULL. I've fixed that as well. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29ocfs2: fix error handling in ocfs2_ioctl_move_extents()Dan Carpenter
Smatch complains that if we hit an error (for example if the file is immutable) then "range" has uninitialized stack data and we copy it to the user. I've re-written the error handling to avoid this problem and make it a little cleaner as well. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29ocfs2: fix error return code in ocfs2_info_handle_freefrag()Wei Yongjun
Fix to return a negative error code from the error handling case instead of 0, as returned elsewhere in this function. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29ocfs2: delay inode update transactions after verifying the input flagsJeff Liu
There is no need to start the inode update transactions before/while verifying the input flags. As a refinement, this patch delay the transactions utill the pre-check up is ok. Signed-off-by: Jie Liu <jeff.liu@oracle.com> Acked-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.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>
2013-03-07fs: Limit sys_mount to only request filesystem modules (Part 2).Eric W. Biederman
Add missing MODULE_ALIAS_FS("ocfs2") how did I miss that? Remove unnecessary MODULE_ALIAS_FS("devpts") devpts can not be modular. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-03fs: Limit sys_mount to only request filesystem modules.Eric W. Biederman
Modify the request_module to prefix the file system type with "fs-" and add aliases to all of the filesystems that can be built as modules to match. A common practice is to build all of the kernel code and leave code that is not commonly needed as modules, with the result that many users are exposed to any bug anywhere in the kernel. Looking for filesystems with a fs- prefix limits the pool of possible modules that can be loaded by mount to just filesystems trivially making things safer with no real cost. Using aliases means user space can control the policy of which filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf with blacklist and alias directives. Allowing simple, safe, well understood work-arounds to known problematic software. This also addresses a rare but unfortunate problem where the filesystem name is not the same as it's module name and module auto-loading would not work. While writing this patch I saw a handful of such cases. The most significant being autofs that lives in the module autofs4. This is relevant to user namespaces because we can reach the request module in get_fs_type() without having any special permissions, and people get uncomfortable when a user specified string (in this case the filesystem type) goes all of the way to request_module. After having looked at this issue I don't think there is any particular reason to perform any filtering or permission checks beyond making it clear in the module request that we want a filesystem module. The common pattern in the kernel is to call request_module() without regards to the users permissions. In general all a filesystem module does once loaded is call register_filesystem() and go to sleep. Which means there is not much attack surface exposed by loading a filesytem module unless the filesystem is mounted. In a user namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT, which most filesystems do not set today. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Reported-by: Kees Cook <keescook@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27ocfs2: convert to idr_alloc()Tejun Heo
Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27ocfs2: ac->ac_allow_chain_relink=0 won't disable group relinkXiaowei.Hu
ocfs2_block_group_alloc_discontig() disables chain relink by setting ac->ac_allow_chain_relink = 0 because it grabs clusters from multiple cluster groups. It doesn't keep the credits for all chain relink,but ocfs2_claim_suballoc_bits overrides this in this call trace: ocfs2_block_group_claim_bits()->ocfs2_claim_clusters()-> __ocfs2_claim_clusters()->ocfs2_claim_suballoc_bits() ocfs2_claim_suballoc_bits set ac->ac_allow_chain_relink = 1; then call ocfs2_search_chain() one time and disable it again, and then we run out of credits. Fix is to allow relink by default and disable it in ocfs2_block_group_alloc_discontig. Without this patch, End-users will run into a crash due to run out of credits, backtrace like this: RIP: 0010:[<ffffffffa0808b14>] [<ffffffffa0808b14>] jbd2_journal_dirty_metadata+0x164/0x170 [jbd2] RSP: 0018:ffff8801b919b5b8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88022139ddc0 RCX: ffff880159f652d0 RDX: ffff880178aa3000 RSI: ffff880159f652d0 RDI: ffff880087f09bf8 RBP: ffff8801b919b5e8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001e00 R11: 00000000000150b0 R12: ffff880159f652d0 R13: ffff8801a0cae908 R14: ffff880087f09bf8 R15: ffff88018d177800 FS: 00007fc9b0b6b6e0(0000) GS:ffff88022fd40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 000000000040819c CR3: 0000000184017000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process dd (pid: 9945, threadinfo ffff8801b919a000, task ffff880149a264c0) Call Trace: ocfs2_journal_dirty+0x2f/0x70 [ocfs2] ocfs2_relink_block_group+0x111/0x480 [ocfs2] ocfs2_search_chain+0x455/0x9a0 [ocfs2] ... Signed-off-by: Xiaowei.Hu <xiaowei.hu@oracle.com> Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27ocfs2: fix ocfs2_init_security_and_acl() to initialize acl correctlyJeff Liu
We need to re-initialize the security for a new reflinked inode with its parent dirs if it isn't specified to be preserved for ocfs2_reflink(). However, the code logic is broken at ocfs2_init_security_and_acl() although ocfs2_init_security_get() succeed. As a result, ocfs2_acl_init() does not involked and therefore the default ACL of parent dir was missing on the new inode. Note this was introduced by 9d8f13ba3 ("security: new security_inode_init_security API adds function callback") To reproduce: set default ACL for the parent dir(ocfs2 in this case): $ setfacl -m default:user:jeff:rwx ../ocfs2/ $ getfacl ../ocfs2/ # file: ../ocfs2/ # owner: jeff # group: jeff user::rwx group::r-x other::r-x default:user::rwx default:user:jeff:rwx default:group::r-x default:mask::rwx default:other::r-x $ touch a $ getfacl a # file: a # owner: jeff # group: jeff user::rw- group::rw- other::r-- Before patching, create reflink file b from a, the user default ACL entry(user:jeff:rwx)was missing: $ ./ocfs2_reflink a b $ getfacl b # file: b # owner: jeff # group: jeff user::rw- group::rw- other::r-- In this case, the end user can also observed an error message at syslog: (ocfs2_reflink,3229,2):ocfs2_init_security_and_acl:7193 ERROR: status = 0 After applying this patch, create reflink file c from a: $ ./ocfs2_reflink a c $ getfacl c # file: c # owner: jeff # group: jeff user::rw- user:jeff:rwx #effective:rw- group::r-x #effective:r-- mask::rw- other::r-- Test program: /* Usage: reflink <source> <dest> */ #include <stdio.h> #include <stdint.h> #include <stdbool.h> #include <string.h> #include <errno.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <sys/ioctl.h> static int reflink_file(char const *src_name, char const *dst_name, bool preserve_attrs) { int fd; #ifndef REFLINK_ATTR_NONE # define REFLINK_ATTR_NONE 0 #endif #ifndef REFLINK_ATTR_PRESERVE # define REFLINK_ATTR_PRESERVE 1 #endif #ifndef OCFS2_IOC_REFLINK struct reflink_arguments { uint64_t old_path; uint64_t new_path; uint64_t preserve; }; # define OCFS2_IOC_REFLINK _IOW ('o', 4, struct reflink_arguments) #endif struct reflink_arguments args = { .old_path = (unsigned long) src_name, .new_path = (unsigned long) dst_name, .preserve = preserve_attrs ? REFLINK_ATTR_PRESERVE : REFLINK_ATTR_NONE, }; fd = open(src_name, O_RDONLY); if (fd < 0) { fprintf(stderr, "Failed to open %s: %s\n", src_name, strerror(errno)); return -1; } if (ioctl(fd, OCFS2_IOC_REFLINK, &args) < 0) { fprintf(stderr, "Failed to reflink %s to %s: %s\n", src_name, dst_name, strerror(errno)); return -1; } } int main(int argc, char *argv[]) { if (argc != 3) { fprintf(stdout, "Usage: %s source dest\n", argv[0]); return 1; } return reflink_file(argv[1], argv[2], 0); } Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Tao Ma <boyu.mt@taobao.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-26Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull ext2, ext3, udf updates from Jan Kara: "Several UDF fixes, a support for UDF extent cache, and couple of ext2 and ext3 cleanups and minor fixes" * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: Ext2: remove the static function release_blocks to optimize the kernel Ext2: mark inode dirty after the function dquot_free_block_nodirty is called Ext2: remove the overhead check about sb in the function ext2_new_blocks udf: Remove unused s_extLength from udf_bitmap udf: Make s_block_bitmap standard array udf: Fix bitmap overflow on large filesystems with small block size udf: add extent cache support in case of file reading udf: Write LVID to disk after opening / closing Ext3: return ENOMEM rather than EIO if sb_getblk fails Ext2: return ENOMEM rather than EIO if sb_getblk fails Ext3: use unlikely to improve the efficiency of the kernel Ext2: use unlikely to improve the efficiency of the kernel Ext3: add necessary check in case IO error happens Ext2: free memory allocated and forget buffer head when io error happens ext3: Fix memory leak when quota options are specified multiple times ext3, ext4, ocfs2: remove unused macro NAMEI_RA_INDEX
2013-02-26ocfs2/dlm: use GFP_ATOMIC inside a spin_lockDan Carpenter
My static checker complains that this is called with a spin_lock held in dlm_master_requery_handler() from dlmrecovery.c. Probably the reason we have not received any bug reports about this is that recovery is not a common operation. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26ocfs2: fix possible use-after-free with AIOJan Kara
Running AIO is pinning inode in memory using file reference. Once AIO is completed using aio_complete(), file reference is put and inode can be freed from memory. So we have to be sure that calling aio_complete() is the last thing we do with the inode. Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Jeff Moyer <jmoyer@redhat.com> Acked-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code pathSunil Mushran
Commit ea022dfb3c2a4680483b00eb2fecc9fc4f6091d1 was missing a var init. Reported-and-Tested-by: Vincent Etienne <vetienne@aprogsys.com> Signed-off-by: Sunil Mushran <sunil.mushran@gmail.com> Signed-off-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26fs: encode_fh: return FILEID_INVALID if invalid fid_typeNamjae Jeon
This patch is a follow up on below patch: [PATCH] exportfs: add FILEID_INVALID to indicate invalid fid_type commit: 216b6cbdcbd86b1db0754d58886b466ae31f5a63 Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Vivek Trivedi <t.vivek@samsung.com> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Sage Weil <sage@inktank.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26kill f_vfsmntAl Viro
very few users left... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace and namespace infrastructure changes from Eric W Biederman: "This set of changes starts with a few small enhnacements to the user namespace. reboot support, allowing more arbitrary mappings, and support for mounting devpts, ramfs, tmpfs, and mqueuefs as just the user namespace root. I do my best to document that if you care about limiting your unprivileged users that when you have the user namespace support enabled you will need to enable memory control groups. There is a minor bug fix to prevent overflowing the stack if someone creates way too many user namespaces. The bulk of the changes are a continuation of the kuid/kgid push down work through the filesystems. These changes make using uids and gids typesafe which ensures that these filesystems are safe to use when multiple user namespaces are in use. The filesystems converted for 3.9 are ceph, 9p, afs, ocfs2, gfs2, ncpfs, nfs, nfsd, and cifs. The changes for these filesystems were a little more involved so I split the changes into smaller hopefully obviously correct changes. XFS is the only filesystem that remains. I was hoping I could get that in this release so that user namespace support would be enabled with an allyesconfig or an allmodconfig but it looks like the xfs changes need another couple of days before it they are ready." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (93 commits) cifs: Enable building with user namespaces enabled. cifs: Convert struct cifs_ses to use a kuid_t and a kgid_t cifs: Convert struct cifs_sb_info to use kuids and kgids cifs: Modify struct smb_vol to use kuids and kgids cifs: Convert struct cifsFileInfo to use a kuid cifs: Convert struct cifs_fattr to use kuid and kgids cifs: Convert struct tcon_link to use a kuid. cifs: Modify struct cifs_unix_set_info_args to hold a kuid_t and a kgid_t cifs: Convert from a kuid before printing current_fsuid cifs: Use kuids and kgids SID to uid/gid mapping cifs: Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID to keyring_alloc cifs: Use BUILD_BUG_ON to validate uids and gids are the same size cifs: Override unmappable incoming uids and gids nfsd: Enable building with user namespaces enabled. nfsd: Properly compare and initialize kuids and kgids nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids nfsd: Modify nfsd4_cb_sec to use kuids and kgids nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion nfsd: Convert nfsxdr to use kuids and kgids nfsd: Convert nfs3xdr to use kuids and kgids ...
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-21Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree from Jiri Kosina: "Assorted tiny fixes queued in trivial tree" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (22 commits) DocBook: update EXPORT_SYMBOL entry to point at export.h Documentation: update top level 00-INDEX file with new additions ARM: at91/ide: remove unsused at91-ide Kconfig entry percpu_counter.h: comment code for better readability x86, efi: fix comment typo in head_32.S IB: cxgb3: delay freeing mem untill entirely done with it net: mvneta: remove unneeded version.h include time: x86: report_lost_ticks doesn't exist any more pcmcia: avoid static analysis complaint about use-after-free fs/jfs: Fix typo in comment : 'how may' -> 'how many' of: add missing documentation for of_platform_populate() btrfs: remove unnecessary cur_trans set before goto loop in join_transaction sound: soc: Fix typo in sound/codecs treewide: Fix typo in various drivers btrfs: fix comment typos Update ibmvscsi module name in Kconfig. powerpc: fix typo (utilties -> utilities) of: fix spelling mistake in comment h8300: Fix home page URL in h8300/README xtensa: Fix home page URL in Kconfig ...
2013-02-21ocfs2: wait for page writeback to provide stable pagesJan Kara
When stable pages are required, we have to wait if the page is just going to disk and we want to modify it. Add proper callback to ocfs2_grab_pages_for_write(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Acked-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Artem Bityutskiy <dedekind1@gmail.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21ocfs2: unlock super lock if lockres refresh failedJunxiao Bi
If lockres refresh failed, the super lock will never be released which will cause some processes on other cluster nodes hung forever. Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21ocfs2: remove kfree() redundant null checksTim Gardner
smatch analysis indicates a number of redundant NULL checks before calling kfree(), eg: fs/ocfs2/alloc.c:6138 ocfs2_begin_truncate_log_recovery() info: redundant null check on *tl_copy calling kfree() fs/ocfs2/alloc.c:6755 ocfs2_zero_range_for_truncate() info: redundant null check on pages calling kfree() etc.... [akpm@linux-foundation.org: revert dubious change in ocfs2_begin_truncate_log_recovery()] Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-13ocfs2: Compare kuids and kgids using uid_eq and gid_eqEric W. Biederman
Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13ocfs2: For tracing report the uid and gid values in the initial user namespaceEric W. Biederman
Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13ocfs2: Convert uid and gids between in core and on disk inodesEric W. Biederman
Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13ocfs2: convert between kuids and kgids and DLM locksEric W. Biederman
Convert between uid and gids stored in the on the wire format of dlm locks aka struct ocfs2_meta_lvb and kuids and kgids stored in inode->i_uid and inode->i_gid. Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13ocfs2: Handle kuids and kgids in acl/xattr conversions.Eric W. Biederman
Explicitly deal with the different kinds of acls because they need different conversions. Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-01-29Merge branch 'master' into for-nextJiri Kosina
Conflicts: drivers/devfreq/exynos4_bus.c Sync with Linus' tree to be able to apply patches that are against newer code (mvneta).
2013-01-21ext3, ext4, ocfs2: remove unused macro NAMEI_RA_INDEXGuo Chao
This macro, initially introduced by ext2 in v0.99.15, does not have any users from the beginning. It has been removed in later ext2 version but still remains in the code of ext3, ext4, ocfs2. Remove this macro there. Cc: Jan Kara <jack@suse.cz> Cc: linux-ext4@vger.kernel.org Cc: ocfs2-devel@oss.oracle.com Acked-by: Mark Fasheh <mfasheh@suse.de> Acked-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Signed-off-by: Jan Kara <jack@suse.cz>
2013-01-09treewide: Fix typo in various driversMasanari Iida
Correct spelling typo in printk within various drivers. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-20ocfs2: drop vmtruncateMarco Stornelli
Removed vmtruncate Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-17lseek: the "whence" argument is called "whence"Andrew Morton
But the kernel decided to call it "origin" instead. Fix most of the sites. Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-11writeback: remove nr_pages_dirtied arg from balance_dirty_pages_ratelimited_nr()Namjae Jeon
There is no reason to pass the nr_pages_dirtied argument, because nr_pages_dirtied value from the caller is unused in balance_dirty_pages_ratelimited_nr(). Signed-off-by: Namjae Jeon <linkinjeon@gmail.com> Signed-off-by: Vivek Trivedi <vtrivedi018@gmail.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09mm: kill vma flag VM_CAN_NONLINEARKonstantin Khlebnikov
Move actual pte filling for non-linear file mappings into the new special vma operation: ->remap_pages(). Filesystems must implement this method to get non-linear mapping support, if it uses filemap_fault() then generic_file_remap_pages() can be used. Now device drivers can implement this method and obtain nonlinear vma support. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> #arch/tile Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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() ...
2012-10-02fs: push rcu_barrier() from deactivate_locked_super() to filesystemsKirill A. Shutemov
There's no reason to call rcu_barrier() on every deactivate_locked_super(). We only need to make sure that all delayed rcu free inodes are flushed before we destroy related cache. Removing rcu_barrier() from deactivate_locked_super() affects some fast paths. E.g. on my machine exit_group() of a last process in IPC namespace takes 0.07538s. rcu_barrier() takes 0.05188s of that time. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
2012-09-26switch o2hb_region_dev_write() to fget_light()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-18userns: Convert struct dquot dq_id to be a struct kqidEric W. Biederman
Change struct dquot dq_id to a struct kqid and remove the now unecessary dq_type. Make minimal changes to dquot, quota_tree, quota_v1, quota_v2, ext3, ext4, and ocfs2 to deal with the change in quota structures and signatures. The ocfs2 changes are larger than most because of the extensive tracing throughout the ocfs2 quota code that prints out dq_id. quota_tree.c:get_index is modified to take a struct kqid instead of a qid_t because all of it's callers pass in dquot->dq_id and it allows me to introduce only a single conversion. The rest of the changes are either just replacing dq_type with dq_id.type, adding conversions to deal with the change in type and occassionally adding qid_eq to allow quota id comparisons in a user namespace safe way. Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Jan Kara <jack@suse.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Theodore Tso <tytso@mit.edu> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18userns: Modify dqget to take struct kqidEric W. Biederman
Modify dqget to take struct kqid instead of a type and an identifier pair. Modify the callers of dqget in ocfs2 and dquot to take generate a struct kqid so they can continue to call dqget. The conversion to create struct kqid should all be the final conversions that are needed in those code paths. Cc: Jan Kara <jack@suse.cz> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18userns: Pass a userns parameter into posix_acl_to_xattr and posix_acl_from_xattrEric W. Biederman
- Pass the user namespace the uid and gid values in the xattr are stored in into posix_acl_from_xattr. - Pass the user namespace kuid and kgid values should be converted into when storing uid and gid values in an xattr in posix_acl_to_xattr. - Modify all callers of posix_acl_from_xattr and posix_acl_to_xattr to pass in &init_user_ns. In the short term this change is not strictly needed but it makes the code clearer. In the longer term this change is necessary to be able to mount filesystems outside of the initial user namespace that natively store posix acls in the linux xattr format. 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>
2012-08-20workqueue: deprecate flush[_delayed]_work_sync()Tejun Heo
flush[_delayed]_work_sync() are now spurious. Mark them deprecated and convert all users to flush[_delayed]_work(). If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant and the regular flushes guarantee that the work item is not pending or running on any CPU on return, so there's no reason to use the sync flushes at all and they're going away. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mattia Dongili <malattia@linux.it> Cc: Kent Yoder <key@linux.vnet.ibm.com> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Bryan Wu <bryan.wu@canonical.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-wireless@vger.kernel.org Cc: Anton Vorontsov <cbou@mail.ru> Cc: Sangbeom Kim <sbkim73@samsung.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Avi Kivity <avi@redhat.com>
2012-08-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ...
2012-07-31ocfs2: Convert to new freezing mechanismJan Kara
Protect ocfs2_page_mkwrite() and ocfs2_file_aio_write() using the new freeze protection. We also protect several ioctl entry points which were missing the protection. Finally, we add freeze protection to the journaling mechanism so that iput() of unlinked inode cannot modify a frozen filesystem. CC: Mark Fasheh <mfasheh@suse.com> CC: Joel Becker <jlbec@evilplan.org> CC: ocfs2-devel@oss.oracle.com Acked-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-30ocfs2: use memweight()Akinobu Mita
Use memweight to count the total number of bits set in memory area. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-29pull mnt_want_write()/mnt_drop_write() into ↵Al Viro
kern_path_create()/done_path_create() resp. One side effect - attempt to create a cross-device link on a read-only fs fails with EROFS instead of EXDEV now. Makes more sense, POSIX allows, etc. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-29new helper: done_path_create()Al Viro
releases what needs to be released after {kern,user}_path_create() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>