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2016-11-18netns: make struct pernet_operations::id unsigned intAlexey Dobriyan
Make struct pernet_operations::id unsigned. There are 2 reasons to do so: 1) This field is really an index into an zero based array and thus is unsigned entity. Using negative value is out-of-bound access by definition. 2) On x86_64 unsigned 32-bit data which are mixed with pointers via array indexing or offsets added or subtracted to pointers are preffered to signed 32-bit data. "int" being used as an array index needs to be sign-extended to 64-bit before being used. void f(long *p, int i) { g(p[i]); } roughly translates to movsx rsi, esi mov rdi, [rsi+...] call g MOVSX is 3 byte instruction which isn't necessary if the variable is unsigned because x86_64 is zero extending by default. Now, there is net_generic() function which, you guessed it right, uses "int" as an array index: static inline void *net_generic(const struct net *net, int id) { ... ptr = ng->ptr[id - 1]; ... } And this function is used a lot, so those sign extensions add up. Patch snipes ~1730 bytes on allyesconfig kernel (without all junk messing with code generation): add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) Unfortunately some functions actually grow bigger. This is a semmingly random artefact of code generation with register allocator being used differently. gcc decides that some variable needs to live in new r8+ registers and every access now requires REX prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be used which is longer than [r8] However, overall balance is in negative direction: add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) function old new delta nfsd4_lock 3886 3959 +73 tipc_link_build_proto_msg 1096 1140 +44 mac80211_hwsim_new_radio 2776 2808 +32 tipc_mon_rcv 1032 1058 +26 svcauth_gss_legacy_init 1413 1429 +16 tipc_bcbase_select_primary 379 392 +13 nfsd4_exchange_id 1247 1260 +13 nfsd4_setclientid_confirm 782 793 +11 ... put_client_renew_locked 494 480 -14 ip_set_sockfn_get 730 716 -14 geneve_sock_add 829 813 -16 nfsd4_sequence_done 721 703 -18 nlmclnt_lookup_host 708 686 -22 nfsd4_lockt 1085 1063 -22 nfs_get_client 1077 1050 -27 tcf_bpf_init 1106 1076 -30 nfsd4_encode_fattr 5997 5930 -67 Total: Before=154856051, After=154854321, chg -0.00% Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-01nfsd: Fix general protection fault in release_lock_stateid()Chuck Lever
When I push NFSv4.1 / RDMA hard, (xfstests generic/089, for example), I get this crash on the server: Oct 28 22:04:30 klimt kernel: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC Oct 28 22:04:30 klimt kernel: Modules linked in: cts rpcsec_gss_krb5 iTCO_wdt iTCO_vendor_support sb_edac edac_core x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm btrfs irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd xor pcspkr raid6_pq i2c_i801 i2c_smbus lpc_ich mfd_core sg mei_me mei ioatdma shpchp wmi ipmi_si ipmi_msghandler rpcrdma ib_ipoib rdma_ucm acpi_power_meter acpi_pad ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c mlx4_ib mlx4_en ib_core sr_mod cdrom sd_mod ast drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel igb ahci libahci ptp mlx4_core pps_core dca libata i2c_algo_bit i2c_core dm_mirror dm_region_hash dm_log dm_mod Oct 28 22:04:30 klimt kernel: CPU: 7 PID: 1558 Comm: nfsd Not tainted 4.9.0-rc2-00005-g82cd754 #8 Oct 28 22:04:30 klimt kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015 Oct 28 22:04:30 klimt kernel: task: ffff880835c3a100 task.stack: ffff8808420d8000 Oct 28 22:04:30 klimt kernel: RIP: 0010:[<ffffffffa05a759f>] [<ffffffffa05a759f>] release_lock_stateid+0x1f/0x60 [nfsd] Oct 28 22:04:30 klimt kernel: RSP: 0018:ffff8808420dbce0 EFLAGS: 00010246 Oct 28 22:04:30 klimt kernel: RAX: ffff88084e6660f0 RBX: ffff88084e667020 RCX: 0000000000000000 Oct 28 22:04:30 klimt kernel: RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffff88084e667020 Oct 28 22:04:30 klimt kernel: RBP: ffff8808420dbcf8 R08: 0000000000000001 R09: 0000000000000000 Oct 28 22:04:30 klimt kernel: R10: ffff880835c3a100 R11: ffff880835c3aca8 R12: 6b6b6b6b6b6b6b6b Oct 28 22:04:30 klimt kernel: R13: ffff88084e6670d8 R14: ffff880835f546f0 R15: ffff880835f1c548 Oct 28 22:04:30 klimt kernel: FS: 0000000000000000(0000) GS:ffff88087bdc0000(0000) knlGS:0000000000000000 Oct 28 22:04:30 klimt kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Oct 28 22:04:30 klimt kernel: CR2: 00007ff020389000 CR3: 0000000001c06000 CR4: 00000000001406e0 Oct 28 22:04:30 klimt kernel: Stack: Oct 28 22:04:30 klimt kernel: ffff88084e667020 0000000000000000 ffff88084e6670d8 ffff8808420dbd20 Oct 28 22:04:30 klimt kernel: ffffffffa05ac80d ffff880835f54548 ffff88084e640008 ffff880835f545b0 Oct 28 22:04:30 klimt kernel: ffff8808420dbd70 ffffffffa059803d ffff880835f1c768 0000000000000870 Oct 28 22:04:30 klimt kernel: Call Trace: Oct 28 22:04:30 klimt kernel: [<ffffffffa05ac80d>] nfsd4_free_stateid+0xfd/0x1b0 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa059803d>] nfsd4_proc_compound+0x40d/0x690 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa0583114>] nfsd_dispatch+0xd4/0x1d0 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa047bbf9>] svc_process_common+0x3d9/0x700 [sunrpc] Oct 28 22:04:30 klimt kernel: [<ffffffffa047ca64>] svc_process+0xf4/0x330 [sunrpc] Oct 28 22:04:30 klimt kernel: [<ffffffffa05827ca>] nfsd+0xfa/0x160 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffffa05826d0>] ? nfsd_destroy+0x170/0x170 [nfsd] Oct 28 22:04:30 klimt kernel: [<ffffffff810b367b>] kthread+0x10b/0x120 Oct 28 22:04:30 klimt kernel: [<ffffffff810b3570>] ? kthread_stop+0x280/0x280 Oct 28 22:04:30 klimt kernel: [<ffffffff8174e8ba>] ret_from_fork+0x2a/0x40 Oct 28 22:04:30 klimt kernel: Code: c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 53 48 8b 87 b0 00 00 00 48 89 fb 4c 8b a0 98 00 00 00 <49> 8b 44 24 20 48 8d b8 80 03 00 00 e8 10 66 1a e1 48 89 df e8 Oct 28 22:04:30 klimt kernel: RIP [<ffffffffa05a759f>] release_lock_stateid+0x1f/0x60 [nfsd] Oct 28 22:04:30 klimt kernel: RSP <ffff8808420dbce0> Oct 28 22:04:30 klimt kernel: ---[ end trace cf5d0b371973e167 ]--- Jeff Layton says: > Hm...now that I look though, this is a little suspicious: > > struct nfs4_openowner *oo = openowner(stp->st_openstp->st_stateowner); > > I wonder if it's possible for the openstateid to have already been > destroyed at this point. > > We might be better off doing something like this to get the client pointer: > > stp->st_stid.sc_client; > > ...which should be more direct and less dependent on other stateids > staying valid. With the suggested change, I am no longer able to reproduce the above oops. v2: Fix unhash_lock_stateid() as well Fix-suggested-by: Jeff Layton <jlayton@redhat.com> Fixes: 42691398be08 ('nfsd: Fix race between FREE_STATEID and LOCK') Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-24nfsd: move blocked lock handling under a dedicated spinlockJeff Layton
Bruce was hitting some lockdep warnings in testing, showing that we could hit a deadlock with the new CB_NOTIFY_LOCK handling, involving a rather complex situation involving four different spinlocks. The crux of the matter is that we end up taking the nn->client_lock in the lm_notify handler. The simplest fix is to just declare a new per-nfsd_net spinlock to protect the new CB_NOTIFY_LOCK structures. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-13Merge tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "Some RDMA work and some good bugfixes, and two new features that could benefit from user testing: - Anna Schumacker contributed a simple NFSv4.2 COPY implementation. COPY is already supported on the client side, so a call to copy_file_range() on a recent client should now result in a server-side copy that doesn't require all the data to make a round trip to the client and back. - Jeff Layton implemented callbacks to notify clients when contended locks become available, which should reduce latency on workloads with contended locks" * tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux: NFSD: Implement the COPY call nfsd: handle EUCLEAN nfsd: only WARN once on unmapped errors exportfs: be careful to only return expected errors. nfsd4: setclientid_confirm with unmatched verifier should fail nfsd: randomize SETCLIENTID reply to help distinguish servers nfsd: set the MAY_NOTIFY_LOCK flag in OPEN replies nfs: add a new NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK constant nfsd: add a LRU list for blocked locks nfsd: have nfsd4_lock use blocking locks for v4.1+ locks nfsd: plumb in a CB_NOTIFY_LOCK operation NFSD: fix corruption in notifier registration svcrdma: support Remote Invalidation svcrdma: Server-side support for rpcrdma_connect_private rpcrdma: RDMA/CM private message data structure svcrdma: Skip put_page() when send_reply() fails svcrdma: Tail iovec leaves an orphaned DMA mapping nfsd: fix dprintk in nfsd4_encode_getdeviceinfo nfsd: eliminate cb_minorversion field nfsd: don't set a FL_LAYOUT lease for flexfiles layouts
2016-10-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: ">rename2() work from Miklos + current_time() from Deepa" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Replace current_fs_time() with current_time() fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps fs: Replace CURRENT_TIME with current_time() for inode timestamps fs: proc: Delete inode time initializations in proc_alloc_inode() vfs: Add current_time() api vfs: add note about i_op->rename changes to porting fs: rename "rename2" i_op to "rename" vfs: remove unused i_op->rename fs: make remaining filesystems use .rename2 libfs: support RENAME_NOREPLACE in simple_rename() fs: support RENAME_NOREPLACE for local filesystems ncpfs: fix unused variable warning
2016-10-10Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted misc bits and pieces. There are several single-topic branches left after this (rename2 series from Miklos, current_time series from Deepa Dinamani, xattr series from Andreas, uaccess stuff from from me) and I'd prefer to send those separately" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits) proc: switch auxv to use of __mem_open() hpfs: support FIEMAP cifs: get rid of unused arguments of CIFSSMBWrite() posix_acl: uapi header split posix_acl: xattr representation cleanups fs/aio.c: eliminate redundant loads in put_aio_ring_file fs/internal.h: add const to ns_dentry_operations declaration compat: remove compat_printk() fs/buffer.c: make __getblk_slow() static proc: unsigned file descriptors fs/file: more unsigned file descriptors fs: compat: remove redundant check of nr_segs cachefiles: Fix attempt to read i_blocks after deleting file [ver #2] cifs: don't use memcpy() to copy struct iov_iter get rid of separate multipage fault-in primitives fs: Avoid premature clearing of capabilities fs: Give dentry to inode_change_ok() instead of inode fuse: Propagate dentry down to inode_change_ok() ceph: Propagate dentry down to inode_change_ok() xfs: Propagate dentry down to inode_change_ok() ...
2016-10-08Merge remote-tracking branch 'jk/vfs' into work.miscAl Viro
2016-10-07cred: simpler, 1D supplementary groupsAlexey Dobriyan
Current supplementary groups code can massively overallocate memory and is implemented in a way so that access to individual gid is done via 2D array. If number of gids is <= 32, memory allocation is more or less tolerable (140/148 bytes). But if it is not, code allocates full page (!) regardless and, what's even more fun, doesn't reuse small 32-entry array. 2D array means dependent shifts, loads and LEAs without possibility to optimize them (gid is never known at compile time). All of the above is unnecessary. Switch to the usual trailing-zero-len-array scheme. Memory is allocated with kmalloc/vmalloc() and only as much as needed. Accesses become simpler (LEA 8(gi,idx,4) or even without displacement). Maximum number of gids is 65536 which translates to 256KB+8 bytes. I think kernel can handle such allocation. On my usual desktop system with whole 9 (nine) aux groups, struct group_info shrinks from 148 bytes to 44 bytes, yay! Nice side effects: - "gi->gid[i]" is shorter than "GROUP_AT(gi, i)", less typing, - fix little mess in net/ipv4/ping.c should have been using GROUP_AT macro but this point becomes moot, - aux group allocation is persistent and should be accounted as such. Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Vasily Kulikov <segoon@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07NFSD: Implement the COPY callAnna Schumaker
I only implemented the sync version of this call, since it's the easiest. I can simply call vfs_copy_range() and have the vfs do the right thing for the filesystem being exported. Signed-off-by: Anna Schumaker <bjschuma@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-07nfsd: handle EUCLEANJ. Bruce Fields
Eric Sandeen reports that xfs can return this if filesystem corruption prevented completing the operation. Reported-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-10-07nfsd: only WARN once on unmapped errorsJ. Bruce Fields
No need to spam the logs here. The only drawback is losing information if we ever encounter two different unmapped errors, but in practice we've rarely see even one. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-27fs: Replace current_fs_time() with current_time()Deepa Dinamani
current_fs_time() uses struct super_block* as an argument. As per Linus's suggestion, this is changed to take struct inode* as a parameter instead. This is because the function is primarily meant for vfs inode timestamps. Also the function was renamed as per Arnd's suggestion. Change all calls to current_fs_time() to use the new current_time() function instead. current_fs_time() will be deleted. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-26nfsd4: setclientid_confirm with unmatched verifier should failJ. Bruce Fields
A setclientid_confirm with (clientid, verifier) both matching an existing confirmed record is assumed to be a replay, but if the verifier doesn't match, it shouldn't be. This would be a very rare case, except that clients following https://tools.ietf.org/html/rfc7931#section-5.8 may depend on the failure. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: randomize SETCLIENTID reply to help distinguish serversJ. Bruce Fields
NFSv4.1 has built-in trunking support that allows a client to determine whether two connections to two different IP addresses are actually to the same server. NFSv4.0 does not, but RFC 7931 attempts to provide clients a means to do this, basically by performing a SETCLIENTID to one address and confirming it with a SETCLIENTID_CONFIRM to the other. Linux clients since 05f4c350ee02 "NFS: Discover NFSv4 server trunking when mounting" implement a variation on this suggestion. It is possible that other clients do too. This depends on the clientid and verifier not being accepted by an unrelated server. Since both are 64-bit values, that would be very unlikely if they were random numbers. But they aren't: knfsd generates the 64-bit clientid by concatenating the 32-bit boot time (in seconds) and a counter. This makes collisions between clientids generated by the same server extremely unlikely. But collisions are very likely between clientids generated by servers that boot at the same time, and it's quite common for multiple servers to boot at the same time. The verifier is a concatenation of the SETCLIENTID time (in seconds) and a counter, so again collisions between different servers are likely if multiple SETCLIENTIDs are done at the same time, which is a common case. Therefore recent NFSv4.0 clients may decide two different servers are really the same, and mount a filesystem from the wrong server. Fortunately the Linux client, since 55b9df93ddd6 "nfsv4/v4.1: Verify the client owner id during trunking detection", only does this when given the non-default "migration" mount option. The fault is really with RFC 7931, and needs a client fix, but in the meantime we can mitigate the chance of these collisions by randomizing the starting value of the counters used to generate clientids and verifiers. Reported-by: Frank Sorenson <fsorenso@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: set the MAY_NOTIFY_LOCK flag in OPEN repliesJeff Layton
If we are using v4.1+, then we can send notification when contended locks become free. Inform the client of that fact. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: add a LRU list for blocked locksJeff Layton
It's possible for a client to call in on a lock that is blocked for a long time, but discontinue polling for it. A malicious client could even set a lock on a file, and then spam the server with failing lock requests from different lockowners that pile up in a DoS attack. Add the blocked lock structures to a per-net namespace LRU when hashing them, and timestamp them. If the lock request is not revisited after a lease period, we'll drop it under the assumption that the client is no longer interested. This also gives us a mechanism to clean up these objects at server shutdown time as well. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: have nfsd4_lock use blocking locks for v4.1+ locksJeff Layton
Create a new per-lockowner+per-inode structure that contains a file_lock. Have nfsd4_lock add this structure to the lockowner's list prior to setting the lock. Then call the vfs and request a blocking lock (by setting FL_SLEEP). If we get anything besides FILE_LOCK_DEFERRED back, then we dequeue the block structure and free it. When the next lock request comes in, we'll look for an existing block for the same filehandle and dequeue and reuse it if there is one. When the lock comes free (a'la an lm_notify call), we dequeue it from the lockowner's list and kick off a CB_NOTIFY_LOCK callback to inform the client that it should retry the lock request. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26nfsd: plumb in a CB_NOTIFY_LOCK operationJeff Layton
Add the encoding/decoding for CB_NOTIFY_LOCK operations. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26NFSD: fix corruption in notifier registrationVasily Averin
By design notifier can be registered once only, however nfsd registers the same inetaddr notifiers per net-namespace. When this happen it corrupts list of notifiers, as result some notifiers can be not called on proper event, traverse on list can be cycled forever, and second unregister can access already freed memory. Cc: stable@vger.kernel.org fixes: 36684996 ("nfsd: Register callbacks on the inetaddr_chain and inet6addr_chain") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-23nfsd: fix dprintk in nfsd4_encode_getdeviceinfoJeff Layton
nfserr is big-endian, so we should convert it to host-endian before printing it. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-22fs: Give dentry to inode_change_ok() instead of inodeJan Kara
inode_change_ok() will be resposible for clearing capabilities and IMA extended attributes and as such will need dentry. Give it as an argument to inode_change_ok() instead of an inode. Also rename inode_change_ok() to setattr_prepare() to better relect that it does also some modifications in addition to checks. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2016-09-16nfsd: eliminate cb_minorversion fieldJeff Layton
We already have that info in the client pointer. No need to pass around a copy. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-16nfsd: don't set a FL_LAYOUT lease for flexfiles layoutsJeff Layton
We currently can hit a deadlock (of sorts) when trying to use flexfiles layouts with XFS. XFS will call break_layout when something wants to write to the file. In the case of the (super-simple) flexfiles layout driver in knfsd, the MDS and DS are the same machine. The client can get a layout and then issue a v3 write to do its I/O. XFS will then call xfs_break_layouts, which will cause a CB_LAYOUTRECALL to be issued to the client. The client however can't return the layout until the v3 WRITE completes, but XFS won't allow the write to proceed until the layout is returned. Christoph says: XFS only cares about block-like layouts where the client has direct access to the file blocks. I'd need to look how to propagate the flag into break_layout, but in principle we don't need to do any recalls on truncate ever for file and flexfile layouts. If we're never going to recall the layout, then we don't even need to set the lease at all. Just skip doing so on flexfiles layouts by adding a new flag to struct nfsd4_layout_ops and skipping the lease setting and removal when that flag is true. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-12nfsd: don't return an unhashed lock stateid after taking mutexJeff Layton
nfsd4_lock will take the st_mutex before working with the stateid it gets, but between the time when we drop the cl_lock and take the mutex, the stateid could become unhashed (a'la FREE_STATEID). If that happens the lock stateid returned to the client will be forgotten. Fix this by first moving the st_mutex acquisition into lookup_or_create_lock_state. Then, have it check to see if the lock stateid is still hashed after taking the mutex. If it's not, then put the stateid and try the find/create again. Signed-off-by: Jeff Layton <jlayton@redhat.com> Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> Cc: stable@vger.kernel.org # feb9dad5 nfsd: Always lock state exclusively. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-11nfsd: Fix race between FREE_STATEID and LOCKChuck Lever
When running LTP's nfslock01 test, the Linux client can send a LOCK and a FREE_STATEID request at the same time. The outcome is: Frame 324 R OPEN stateid [2,O] Frame 115004 C LOCK lockowner_is_new stateid [2,O] offset 672000 len 64 Frame 115008 R LOCK stateid [1,L] Frame 115012 C WRITE stateid [0,L] offset 672000 len 64 Frame 115016 R WRITE NFS4_OK Frame 115019 C LOCKU stateid [1,L] offset 672000 len 64 Frame 115022 R LOCKU NFS4_OK Frame 115025 C FREE_STATEID stateid [2,L] Frame 115026 C LOCK lockowner_is_new stateid [2,O] offset 672128 len 64 Frame 115029 R FREE_STATEID NFS4_OK Frame 115030 R LOCK stateid [3,L] Frame 115034 C WRITE stateid [0,L] offset 672128 len 64 Frame 115038 R WRITE NFS4ERR_BAD_STATEID In other words, the server returns stateid L in a successful LOCK reply, but it has already released it. Subsequent uses of stateid L fail. To address this, protect the generation check in nfsd4_free_stateid with the st_mutex. This should guarantee that only one of two outcomes occurs: either LOCK returns a fresh valid stateid, or FREE_STATEID returns NFS4ERR_LOCKS_HELD. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Fix-suggested-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-11nfsd: fix dentry refcounting on createJosef Bacik
b44061d0b9 introduced a dentry ref counting bug. Previously we were grabbing one ref to dchild in nfsd_create(), but with the creation of nfsd_create_locked() we have a ref for dchild from the lookup in nfsd_create(), and then another ref in nfsd_create_locked(). The ref from the lookup in nfsd_create() is never dropped and results in dentries still in use at unmount. Signed-off-by: Josef Bacik <jbacik@fb.com> Fixes: b44061d0b9 "nfsd: reorganize nfsd_create" Reported-by: kernel test robot <xiaolong.ye@intel.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04Merge tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "Highlights: - Trond made a change to the server's tcp logic that allows a fast client to better take advantage of high bandwidth networks, but may increase the risk that a single client could starve other clients; a new sunrpc.svc_rpc_per_connection_limit parameter should help mitigate this in the (hopefully unlikely) event this becomes a problem in practice. - Tom Haynes added a minimal flex-layout pnfs server, which is of no use in production for now--don't build it unless you're doing client testing or further server development" * tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux: (32 commits) nfsd: remove some dead code in nfsd_create_locked() nfsd: drop unnecessary MAY_EXEC check from create nfsd: clean up bad-type check in nfsd_create_locked nfsd: remove unnecessary positive-dentry check nfsd: reorganize nfsd_create nfsd: check d_can_lookup in fh_verify of directories nfsd: remove redundant zero-length check from create nfsd: Make creates return EEXIST instead of EACCES SUNRPC: Detect immediate closure of accepted sockets SUNRPC: accept() may return sockets that are still in SYN_RECV nfsd: allow nfsd to advertise multiple layout types nfsd: Close race between nfsd4_release_lockowner and nfsd4_lock nfsd/blocklayout: Make sure calculate signature/designator length aligned xfs: abstract block export operations from nfsd layouts SUNRPC: Remove unused callback xpo_adjust_wspace() SUNRPC: Change TCP socket space reservation SUNRPC: Add a server side per-connection limit SUNRPC: Micro optimisation for svc_data_ready SUNRPC: Call the default socket callbacks instead of open coding SUNRPC: lock the socket while detaching it ...
2016-08-04nfsd: remove some dead code in nfsd_create_locked()Dan Carpenter
We changed this around in f135af1041f ('nfsd: reorganize nfsd_create') so "dchild" can't be an error pointer any more. Also, dchild can't be NULL here (and dput would already handle this even if it was). Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: drop unnecessary MAY_EXEC check from createJ. Bruce Fields
We need an fh_verify to make sure we at least have a dentry, but actual permission checks happen later. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: clean up bad-type check in nfsd_create_lockedJ. Bruce Fields
Minor cleanup, no change in behavior. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: remove unnecessary positive-dentry checkJ. Bruce Fields
vfs_{create,mkdir,mknod} each begin with a call to may_create(), which returns EEXIST if the object already exists. This check is therefore unnecessary. (In the NFSv2 case, nfsd_proc_create also has such a check. Contrary to RFC 1094, our code seems to believe that a CREATE of an existing file should succeed. I'm leaving that behavior alone.) Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: reorganize nfsd_createJ. Bruce Fields
There's some odd logic in nfsd_create() that allows it to be called with the parent directory either locked or unlocked. The only already-locked caller is NFSv2's nfsd_proc_create(). It's less confusing to split out the unlocked case into a separate function which the NFSv2 code can call directly. Also fix some comments while we're here. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: check d_can_lookup in fh_verify of directoriesJ. Bruce Fields
Create and other nfsd ops generally assume we can call lookup_one_len on inodes with S_IFDIR set. Al says that this assumption isn't true in general, though it should be for the filesystem objects nfsd sees. Add a check just to make sure our assumption isn't violated. Remove a couple checks for i_op->lookup in create code. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: remove redundant zero-length check from createJ. Bruce Fields
lookup_one_len already has this check. The only effect of this patch is to return access instead of perm in the 0-length-filename case. I actually prefer nfserr_perm (or _inval?), but I doubt anyone cares. The isdotent check seems redundant too, but I worry that some client might actually care about that strange nfserr_exist error. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-08-04nfsd: Make creates return EEXIST instead of EACCESOleg Drokin
When doing a create (mkdir/mknod) on a name, it's worth checking the name exists first before returning EACCES in case the directory is not writeable by the user. This makes return values on the client more consistent regardless of whenever the entry there is cached in the local cache or not. Another positive side effect is certain programs only expect EEXIST in that case even despite POSIX allowing any valid error to be returned. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-29Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull userns vfs updates from Eric Biederman: "This tree contains some very long awaited work on generalizing the user namespace support for mounting filesystems to include filesystems with a backing store. The real world target is fuse but the goal is to update the vfs to allow any filesystem to be supported. This patchset is based on a lot of code review and testing to approach that goal. While looking at what is needed to support the fuse filesystem it became clear that there were things like xattrs for security modules that needed special treatment. That the resolution of those concerns would not be fuse specific. That sorting out these general issues made most sense at the generic level, where the right people could be drawn into the conversation, and the issues could be solved for everyone. At a high level what this patchset does a couple of simple things: - Add a user namespace owner (s_user_ns) to struct super_block. - Teach the vfs to handle filesystem uids and gids not mapping into to kuids and kgids and being reported as INVALID_UID and INVALID_GID in vfs data structures. By assigning a user namespace owner filesystems that are mounted with only user namespace privilege can be detected. This allows security modules and the like to know which mounts may not be trusted. This also allows the set of uids and gids that are communicated to the filesystem to be capped at the set of kuids and kgids that are in the owning user namespace of the filesystem. One of the crazier corner casees this handles is the case of inodes whose i_uid or i_gid are not mapped into the vfs. Most of the code simply doesn't care but it is easy to confuse the inode writeback path so no operation that could cause an inode write-back is permitted for such inodes (aka only reads are allowed). This set of changes starts out by cleaning up the code paths involved in user namespace permirted mounts. Then when things are clean enough adds code that cleanly sets s_user_ns. Then additional restrictions are added that are possible now that the filesystem superblock contains owner information. These changes should not affect anyone in practice, but there are some parts of these restrictions that are changes in behavior. - Andy's restriction on suid executables that does not honor the suid bit when the path is from another mount namespace (think /proc/[pid]/fd/) or when the filesystem was mounted by a less privileged user. - The replacement of the user namespace implicit setting of MNT_NODEV with implicitly setting SB_I_NODEV on the filesystem superblock instead. Using SB_I_NODEV is a stronger form that happens to make this state user invisible. The user visibility can be managed but it caused problems when it was introduced from applications reasonably expecting mount flags to be what they were set to. There is a little bit of work remaining before it is safe to support mounting filesystems with backing store in user namespaces, beyond what is in this set of changes. - Verifying the mounter has permission to read/write the block device during mount. - Teaching the integrity modules IMA and EVM to handle filesystems mounted with only user namespace root and to reduce trust in their security xattrs accordingly. - Capturing the mounters credentials and using that for permission checks in d_automount and the like. (Given that overlayfs already does this, and we need the work in d_automount it make sense to generalize this case). Furthermore there are a few changes that are on the wishlist: - Get all filesystems supporting posix acls using the generic posix acls so that posix_acl_fix_xattr_from_user and posix_acl_fix_xattr_to_user may be removed. [Maintainability] - Reducing the permission checks in places such as remount to allow the superblock owner to perform them. - Allowing the superblock owner to chown files with unmapped uids and gids to something that is mapped so the files may be treated normally. I am not considering even obvious relaxations of permission checks until it is clear there are no more corner cases that need to be locked down and handled generically. Many thanks to Seth Forshee who kept this code alive, and putting up with me rewriting substantial portions of what he did to handle more corner cases, and for his diligent testing and reviewing of my changes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (30 commits) fs: Call d_automount with the filesystems creds fs: Update i_[ug]id_(read|write) to translate relative to s_user_ns evm: Translate user/group ids relative to s_user_ns when computing HMAC dquot: For now explicitly don't support filesystems outside of init_user_ns quota: Handle quota data stored in s_user_ns in quota_setxquota quota: Ensure qids map to the filesystem vfs: Don't create inodes with a uid or gid unknown to the vfs vfs: Don't modify inodes with a uid or gid unknown to the vfs cred: Reject inodes with invalid ids in set_create_file_as() fs: Check for invalid i_uid in may_follow_link() vfs: Verify acls are valid within superblock's s_user_ns. userns: Handle -1 in k[ug]id_has_mapping when !CONFIG_USER_NS fs: Refuse uid/gid changes which don't map into s_user_ns selinux: Add support for unprivileged mounts from user namespaces Smack: Handle labels consistently in untrusted mounts Smack: Add support for unprivileged mounts from user namespaces fs: Treat foreign mounts as nosuid fs: Limit file caps to the user namespace of the super block userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag userns: Remove implicit MNT_NODEV fragility. ...
2016-07-28Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "Assorted cleanups and fixes. Probably the most interesting part long-term is ->d_init() - that will have a bunch of followups in (at least) ceph and lustre, but we'll need to sort the barrier-related rules before it can get used for really non-trivial stuff. Another fun thing is the merge of ->d_iput() callers (dentry_iput() and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all except the one in __d_lookup_lru())" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits) fs/dcache.c: avoid soft-lockup in dput() vfs: new d_init method vfs: Update lookup_dcache() comment bdev: get rid of ->bd_inodes Remove last traces of ->sync_page new helper: d_same_name() dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends() vfs: clean up documentation vfs: document ->d_real() vfs: merge .d_select_inode() into .d_real() unify dentry_iput() and dentry_unlink_inode() binfmt_misc: ->s_root is not going anywhere drop redundant ->owner initializations ufs: get rid of redundant checks orangefs: constify inode_operations missed comment updates from ->direct_IO() prototype change file_inode(f)->i_mapping is f->f_mapping trim fsnotify hooks a bit 9p: new helper - v9fs_parent_fid() debugfs: ->d_parent is never NULL or negative ...
2016-07-27Merge tag 'xfs-for-linus-4.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs Pull xfs updates from Dave Chinner: "The major addition is the new iomap based block mapping infrastructure. We've been kicking this about locally for years, but there are other filesystems want to use it too (e.g. gfs2). Now it is fully working, reviewed and ready for merge and be used by other filesystems. There are a lot of other fixes and cleanups in the tree, but those are XFS internal things and none are of the scale or visibility of the iomap changes. See below for details. I am likely to send another pull request next week - we're just about ready to merge some new functionality (on disk block->owner reverse mapping infrastructure), but that's a huge chunk of code (74 files changed, 7283 insertions(+), 1114 deletions(-)) so I'm keeping that separate to all the "normal" pull request changes so they don't get lost in the noise. Summary of changes in this update: - generic iomap based IO path infrastructure - generic iomap based fiemap implementation - xfs iomap based Io path implementation - buffer error handling fixes - tracking of in flight buffer IO for unmount serialisation - direct IO and DAX io path separation and simplification - shortform directory format definition changes for wider platform compatibility - various buffer cache fixes - cleanups in preparation for rmap merge - error injection cleanups and fixes - log item format buffer memory allocation restructuring to prevent rare OOM reclaim deadlocks - sparse inode chunks are now fully supported" * tag 'xfs-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (53 commits) xfs: remove EXPERIMENTAL tag from sparse inode feature xfs: bufferhead chains are invalid after end_page_writeback xfs: allocate log vector buffers outside CIL context lock libxfs: directory node splitting does not have an extra block xfs: remove dax code from object file when disabled xfs: skip dirty pages in ->releasepage() xfs: remove __arch_pack xfs: kill xfs_dir2_inou_t xfs: kill xfs_dir2_sf_off_t xfs: split direct I/O and DAX path xfs: direct calls in the direct I/O path xfs: stop using generic_file_read_iter for direct I/O xfs: split xfs_file_read_iter into buffered and direct I/O helpers xfs: remove s_maxbytes enforcement in xfs_file_read_iter xfs: kill ioflags xfs: don't pass ioflags around in the ioctl path xfs: track and serialize in-flight async buffers against unmount xfs: exclude never-released buffers from buftarg I/O accounting xfs: don't reset b_retries to 0 on every failure xfs: remove extraneous buffer flag changes ...
2016-07-15nfsd: allow nfsd to advertise multiple layout typesJeff Layton
If the underlying filesystem supports multiple layout types, then there is little reason not to advertise that fact to clients and let them choose what type to use. Turn the ex_layout_type field into a bitfield. For each supported layout type, we set a bit in that field. When the client requests a layout, ensure that the bit for that layout type is set. When the client requests attributes, send back a list of supported types. Signed-off-by: Jeff Layton <jlayton@poochiereds.net> Reviewed-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-15nfsd: Close race between nfsd4_release_lockowner and nfsd4_lockChuck Lever
nfsd4_release_lockowner finds a lock owner that has no lock state, and drops cl_lock. Then release_lockowner picks up cl_lock and unhashes the lock owner. During the window where cl_lock is dropped, I don't see anything preventing a concurrent nfsd4_lock from finding that same lock owner and adding lock state to it. Move release_lockowner() into nfsd4_release_lockowner and hang onto the cl_lock until after the lock owner's state cannot be found again. Found by inspection, we don't currently have a reproducer. Fixes: 2c41beb0e5cf ("nfsd: reduce cl_lock thrashing in ... ") Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-15nfsd/blocklayout: Make sure calculate signature/designator length alignedKinglong Mee
These values are all multiples of 4 already, so there's no change in behavior from this patch. But perhaps this will prevent mistakes in the future. Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-15xfs: abstract block export operations from nfsd layoutsBenjamin Coddington
Instead of creeping pnfs layout configuration into filesystems, move the definition of block-based export operations under a more abstract configuration. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Dave Chinner <david@fromorbit.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: Fix some indent inconsistancyChristophe JAILLET
Silent a few smatch warnings about indentation Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: Correct a comment for NFSD_MAY_ defines locationOleg Drokin
Those are now defined in fs/nfsd/vfs.h Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Reviewed-by: Jeff Layton <jlayton@poochiereds.net> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: Add a super simple flex file serverTom Haynes
Have a simple flex file server where the mds (NFSv4.1 or NFSv4.2) is also the ds (NFSv3). I.e., the metadata and the data file are the exact same file. This will allow testing of the flex file client. Simply add the "pnfs" export option to your export in /etc/exports and mount from a client that supports flex files. Signed-off-by: Tom Haynes <loghyr@primarydata.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: flex file device id encoding will need the server addressTom Haynes
Signed-off-by: Tom Haynes <loghyr@primarydata.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jeff Layton <jlayton@poochiereds.net> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: implement machine credential support for some operationsAndrew Elble
This addresses the conundrum referenced in RFC5661 18.35.3, and will allow clients to return state to the server using the machine credentials. The biggest part of the problem is that we need to allow the client to send a compound op with integrity/privacy on mounts that don't have it enabled. Add server support for properly decoding and using spo_must_enforce and spo_must_allow bits. Add support for machine credentials to be used for CLOSE, OPEN_DOWNGRADE, LOCKU, DELEGRETURN, and TEST/FREE STATEID. Implement a check so as to not throw WRONGSEC errors when these operations are used if integrity/privacy isn't turned on. Without this, Linux clients with credentials that expired while holding delegations were getting stuck in an endless loop. Signed-off-by: Andrew Elble <aweits@rit.edu> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: allow mach_creds_match to be used more broadlyAndrew Elble
Rename mach_creds_match() to nfsd4_mach_creds_match() and un-staticify Signed-off-by: Andrew Elble <aweits@rit.edu> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-06-30Merge branch 'd_real' of ↵Al Viro
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into work.misc
2016-06-24nfsd: check permissions when setting ACLsBen Hutchings
Use set_posix_acl, which includes proper permission checks, instead of calling ->set_acl directly. Without this anyone may be able to grant themselves permissions to a file by setting the ACL. Lock the inode to make the new checks atomic with respect to set_acl. (Also, nfsd was the only caller of set_acl not locking the inode, so I suspect this may fix other races.) This also simplifies the code, and ensures our ACLs are checked by posix_acl_valid. The permission checks and the inode locking were lost with commit 4ac7249e, which changed nfsd to use the set_acl inode operation directly instead of going through xattr handlers. Reported-by: David Sinquin <david@sinquin.eu> [agreunba@redhat.com: use set_posix_acl] Fixes: 4ac7249e Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>