linux-toradex.git/fs/nfs/dir.c, branch tegra-11.2.10

NFS: Fix an Oops in the NFSv4 atomic open code

2010-08-18T13:25:42+00:00

Adam Lackorzynski reports:

with 2.6.35.2 I'm getting this reproducible Oops:

[  110.825396] BUG: unable to handle kernel NULL pointer dereference at
(null)
[  110.828638] IP: [] encode_attrs+0x1a/0x2a4
[  110.828638] PGD be89f067 PUD bf18f067 PMD 0
[  110.828638] Oops: 0000 [#1] SMP
[  110.828638] last sysfs file: /sys/class/net/lo/operstate
[  110.828638] CPU 2
[  110.828638] Modules linked in: rtc_cmos rtc_core rtc_lib amd64_edac_mod
i2c_amd756 edac_core i2c_core dm_mirror dm_region_hash dm_log dm_snapshot
sg sr_mod usb_storage ohci_hcd mptspi tg3 mptscsih mptbase usbcore nls_base
[last unloaded: scsi_wait_scan]
[  110.828638]
[  110.828638] Pid: 11264, comm: setchecksum Not tainted 2.6.35.2 #1
[  110.828638] RIP: 0010:[]  []
encode_attrs+0x1a/0x2a4
[  110.828638] RSP: 0000:ffff88003bf5b878  EFLAGS: 00010296
[  110.828638] RAX: ffff8800bddb48a8 RBX: ffff88003bf5bb18 RCX:
0000000000000000
[  110.828638] RDX: ffff8800be258800 RSI: 0000000000000000 RDI:
ffff88003bf5b9f8
[  110.828638] RBP: 0000000000000000 R08: ffff8800bddb48a8 R09:
0000000000000004
[  110.828638] R10: 0000000000000003 R11: ffff8800be779000 R12:
ffff8800be258800
[  110.828638] R13: ffff88003bf5b9f8 R14: ffff88003bf5bb20 R15:
ffff8800be258800
[  110.828638] FS:  0000000000000000(0000) GS:ffff880041e00000(0063)
knlGS:00000000556bd6b0
[  110.828638] CS:  0010 DS: 002b ES: 002b CR0: 000000008005003b
[  110.828638] CR2: 0000000000000000 CR3: 00000000be8ef000 CR4:
00000000000006e0
[  110.828638] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[  110.828638] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[  110.828638] Process setchecksum (pid: 11264, threadinfo
ffff88003bf5a000, task ffff88003f232210)
[  110.828638] Stack:
[  110.828638]  0000000000000000 ffff8800bfbcf920 0000000000000000
0000000000000ffe
[  110.828638] <0> 0000000000000000 0000000000000000 0000000000000000
0000000000000000
[  110.828638] <0> 0000000000000000 0000000000000000 0000000000000000
0000000000000000
[  110.828638] Call Trace:
[  110.828638]  [] ? nfs4_xdr_enc_setattr+0x90/0xb4
[  110.828638]  [] ? call_transmit+0x1c3/0x24a
[  110.828638]  [] ? __rpc_execute+0x78/0x22a
[  110.828638]  [] ? rpc_run_task+0x21/0x2b
[  110.828638]  [] ? rpc_call_sync+0x3d/0x5d
[  110.828638]  [] ? _nfs4_do_setattr+0x11b/0x147
[  110.828638]  [] ? nfs_init_locked+0x0/0x32
[  110.828638]  [] ? ifind+0x4e/0x90
[  110.828638]  [] ? nfs4_do_setattr+0x4b/0x6e
[  110.828638]  [] ? nfs4_do_open+0x291/0x3a6
[  110.828638]  [] ? nfs4_open_revalidate+0x63/0x14a
[  110.828638]  [] ? nfs_open_revalidate+0xd7/0x161
[  110.828638]  [] ? do_lookup+0x1a4/0x201
[  110.828638]  [] ? link_path_walk+0x6a/0x9d5
[  110.828638]  [] ? do_last+0x17b/0x58e
[  110.828638]  [] ? do_filp_open+0x1bd/0x56e
[  110.828638]  [] ? _atomic_dec_and_lock+0x30/0x48
[  110.828638]  [] ? dput+0x37/0x152
[  110.828638]  [] ? alloc_fd+0x69/0x10a
[  110.828638]  [] ? do_sys_open+0x56/0x100
[  110.828638]  [] ? ia32_sysret+0x0/0x5
[  110.828638] Code: 83 f1 01 e8 f5 ca ff ff 48 83 c4 50 5b 5d 41 5c c3 41
57 41 56 41 55 49 89 fd 41 54 49 89 d4 55 48 89 f5 53 48 81 ec 18 01 00 00
<8b> 06 89 c2 83 e2 08 83 fa 01 19 db 83 e3 f8 83 c3 18 a8 01 8d
[  110.828638] RIP  [] encode_attrs+0x1a/0x2a4
[  110.828638]  RSP 
[  110.828638] CR2: 0000000000000000
[  112.840396] ---[ end trace 95282e83fd77358f ]---

We need to ensure that the O_EXCL flag is turned off if the user doesn't
set O_CREAT.

Cc: stable@kernel.org
Signed-off-by: Trond Myklebust

NFS: allow close-to-open cache semantics to apply to root of NFS filesystem

2010-08-10T14:20:05+00:00

To obey NFS cache semantics, the client must verify the cached
attributes when a file is opened.  In most cases this is done by a call to
d_validate as one of the last steps in path_walk.

However for the root of a filesystem, d_validate is only ever called
on the mounted-on filesystem (except when the path ends '.' or '..').
So NFS has no chance to validate the attributes.

So, in nfs_opendir, we revalidate the attributes if the opened
directory is the mountpoint.  This may cause double-validation for "."
and ".." lookups, but that is better than missing regular /path/name
lookups completely.

Signed-off-by: NeilBrown 
Signed-off-by: Trond Myklebust

Merge branch 'nfs-for-2.6.36' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

2010-08-07T20:19:36+00:00

* 'nfs-for-2.6.36' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (42 commits)
  NFS: NFSv4.1 is no longer a "developer only" feature
  NFS: NFS_V4 is no longer an EXPERIMENTAL feature
  NFS: Fix /proc/mount for legacy binary interface
  NFS: Fix the locking in nfs4_callback_getattr
  SUNRPC: Defer deleting the security context until gss_do_free_ctx()
  SUNRPC: prevent task_cleanup running on freed xprt
  SUNRPC: Reduce asynchronous RPC task stack usage
  SUNRPC: Move the bound cred to struct rpc_rqst
  SUNRPC: Clean up of rpc_bindcred()
  SUNRPC: Move remaining RPC client related task initialisation into clnt.c
  SUNRPC: Ensure that rpc_exit() always wakes up a sleeping task
  SUNRPC: Make the credential cache hashtable size configurable
  SUNRPC: Store the hashtable size in struct rpc_cred_cache
  NFS: Ensure the AUTH_UNIX credcache is allocated dynamically
  NFS: Fix the NFS users of rpc_restart_call()
  SUNRPC: The function rpc_restart_call() should return success/failure
  NFSv4: Get rid of the bogus RPC_ASSASSINATED(task) checks
  NFSv4: Clean up the process of renewing the NFSv4 lease
  NFSv4.1: Handle NFS4ERR_DELAY on SEQUENCE correctly
  NFS: nfs_rename() should not have to flush out writebacks
  ...

NFS: nfs_rename() should not have to flush out writebacks

2010-08-04T02:06:41+00:00

We don't really support nfs servers that invalidate the file handle after a
rename, so precautions such as flushing out dirty data before renaming the
file are superfluous.

Signed-off-by: Trond Myklebust

vfs: re-introduce MAY_CHDIR

2010-08-02T05:35:06+00:00

Currently MAY_ACCESS means that filesystems must check the permissions
right then and not rely on cached results or the results of future
operations on the object.  This can be because of a call to sys_access() or
because of a call to chdir() which needs to check search without relying on
any future operations inside that dir.  I plan to use MAY_ACCESS for other
purposes in the security system, so I split the MAY_ACCESS and the
MAY_CHDIR cases.

Signed-off-by: Eric Paris 
Acked-by:  Stephen D. Smalley 
Signed-off-by: James Morris

mm: add context argument to shrinker callback

2010-07-19T04:56:17+00:00

The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().

Signed-off-by: Dave Chinner 
Reviewed-by: Christoph Hellwig

drop unused dentry argument to ->fsync

2010-05-28T02:05:02+00:00

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

NFS: Fix a lock imbalance typo in nfs_access_cache_shrinker

2010-05-26T12:43:51+00:00

Commit 9c7e7e23371e629dbb3b341610a418cdf1c19d91 (NFS: Don't call iput() in
nfs_access_cache_shrinker) unintentionally removed the spin unlock for the
inode->i_lock.

Reported-by: David Howells 
Signed-off-by: Trond Myklebust

NFS: Don't call iput() in nfs_access_cache_shrinker

2010-05-14T19:09:36+00:00

iput() can potentially attempt to allocate memory, so we should avoid
calling it in a memory shrinker. Instead, rely on the fact that iput() will
call nfs_access_zap_cache().

Signed-off-by: Trond Myklebust

NFS: Clean up nfs_access_zap_cache()

2010-05-14T19:09:35+00:00

Signed-off-by: Trond Myklebust