linux-stable.git/fs, branch v3.10.70

ext4: prevent bugon on race between write/fcntl

2015-02-11T06:48:17+00:00

commit a41537e69b4aa43f0fea02498c2595a81267383b upstream.

O_DIRECT flags can be toggeled via fcntl(F_SETFL). But this value checked
twice inside ext4_file_write_iter() and __generic_file_write() which
result in BUG_ON inside ext4_direct_IO.

Let's initialize iocb->private unconditionally.

TESTCASE: xfstest:generic/036  https://patchwork.ozlabs.org/patch/402445/

#TYPICAL STACK TRACE:
kernel BUG at fs/ext4/inode.c:2960!
invalid opcode: 0000 [#1] SMP
Modules linked in: brd iTCO_wdt lpc_ich mfd_core igb ptp dm_mirror dm_region_hash dm_log dm_mod
CPU: 6 PID: 5505 Comm: aio-dio-fcntl-r Not tainted 3.17.0-rc2-00176-gff5c017 #161
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
task: ffff88080e95a7c0 ti: ffff88080f908000 task.ti: ffff88080f908000
RIP: 0010:[]  [] ext4_direct_IO+0x162/0x3d0
RSP: 0018:ffff88080f90bb58  EFLAGS: 00010246
RAX: 0000000000000400 RBX: ffff88080fdb2a28 RCX: 00000000a802c818
RDX: 0000040000080000 RSI: ffff88080d8aeb80 RDI: 0000000000000001
RBP: ffff88080f90bbc8 R08: 0000000000000000 R09: 0000000000001581
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88080d8aeb80
R13: ffff88080f90bbf8 R14: ffff88080fdb28c8 R15: ffff88080fdb2a28
FS:  00007f23b2055700(0000) GS:ffff880818400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f23b2045000 CR3: 000000080cedf000 CR4: 00000000000407e0
Stack:
 ffff88080f90bb98 0000000000000000 7ffffffffffffffe ffff88080fdb2c30
 0000000000000200 0000000000000200 0000000000000001 0000000000000200
 ffff88080f90bbc8 ffff88080fdb2c30 ffff88080f90be08 0000000000000200
Call Trace:
 [] generic_file_direct_write+0xed/0x180
 [] __generic_file_write_iter+0x222/0x370
 [] ext4_file_write_iter+0x34b/0x400
 [] ? aio_run_iocb+0x239/0x410
 [] ? aio_run_iocb+0x239/0x410
 [] ? local_clock+0x25/0x30
 [] ? __lock_acquire+0x274/0x700
 [] ? ext4_unwritten_wait+0xb0/0xb0
 [] aio_run_iocb+0x286/0x410
 [] ? local_clock+0x25/0x30
 [] ? lock_release_holdtime+0x29/0x190
 [] ? lookup_ioctx+0x4b/0xf0
 [] do_io_submit+0x55b/0x740
 [] ? do_io_submit+0x3ca/0x740
 [] SyS_io_submit+0x10/0x20
 [] system_call_fastpath+0x16/0x1b
Code: 01 48 8b 80 f0 01 00 00 48 8b 18 49 8b 45 10 0f 85 f1 01 00 00 48 03 45 c8 48 3b 43 48 0f 8f e3 01 00 00 49 83 7c
24 18 00 75 04 <0f> 0b eb fe f0 ff 83 ec 01 00 00 49 8b 44 24 18 8b 00 85 c0 89
RIP  [] ext4_direct_IO+0x162/0x3d0
 RSP 

Reported-by: Sasha Levin 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Dmitry Monakhov 
[hujianyang: Backported to 3.10
 - Move initialization of iocb->private to ext4_file_write() as we don't
   have ext4_file_write_iter(), which is introduced by commit 9b884164.
 - Adjust context to make 'overwrite' changes apply to ext4_file_dio_write()
   as ext4_file_dio_write() is not move into ext4_file_write()]
Signed-off-by: hujianyang 
Signed-off-by: Greg Kroah-Hartman

nilfs2: fix deadlock of segment constructor over I_SYNC flag

2015-02-11T06:48:16+00:00

commit 7ef3ff2fea8bf5e4a21cef47ad87710a3d0fdb52 upstream.

Nilfs2 eventually hangs in a stress test with fsstress program.  This
issue was caused by the following deadlock over I_SYNC flag between
nilfs_segctor_thread() and writeback_sb_inodes():

  nilfs_segctor_thread()
    nilfs_segctor_thread_construct()
      nilfs_segctor_unlock()
        nilfs_dispose_list()
          iput()
            iput_final()
              evict()
                inode_wait_for_writeback()  * wait for I_SYNC flag

  writeback_sb_inodes()
     * set I_SYNC flag on inode->i_state
    __writeback_single_inode()
      do_writepages()
        nilfs_writepages()
          nilfs_construct_dsync_segment()
            nilfs_segctor_sync()
               * wait for completion of segment constructor
    inode_sync_complete()
       * clear I_SYNC flag after __writeback_single_inode() completed

writeback_sb_inodes() calls do_writepages() for dirty inodes after
setting I_SYNC flag on inode->i_state.  do_writepages() in turn calls
nilfs_writepages(), which can run segment constructor and wait for its
completion.  On the other hand, segment constructor calls iput(), which
can call evict() and wait for the I_SYNC flag on
inode_wait_for_writeback().

Since segment constructor doesn't know when I_SYNC will be set, it
cannot know whether iput() will block or not unless inode->i_nlink has a
non-zero count.  We can prevent evict() from being called in iput() by
implementing sop->drop_inode(), but it's not preferable to leave inodes
with i_nlink == 0 for long periods because it even defers file
truncation and inode deallocation.  So, this instead resolves the
deadlock by calling iput() asynchronously with a workqueue for inodes
with i_nlink == 0.

Signed-off-by: Ryusuke Konishi 
Cc: Al Viro 
Tested-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

pstore/ram: avoid atomic accesses for ioremapped regions

2015-02-06T06:35:40+00:00

commit 0405a5cec3406f19e69da07c8111a6bf1088ac29 upstream.

For persistent RAM outside of main memory, the memory may have limitations
on supported accesses. For internal RAM on highbank platform exclusive
accesses are not supported and will hang the system. So atomic_cmpxchg
cannot be used. This commit uses spinlock protection for buffer size and
start updates on ioremapped regions instead.

Signed-off-by: Rob Herring 
Acked-by: Anton Vorontsov 
Signed-off-by: Tony Luck 
[hkp: Backported to 3.10: adjust context]
Signed-off-by: HuKeping

pstore: Fix NULL pointer fault if get NULL prz in ramoops_get_next_prz

2015-02-06T06:35:40+00:00

commit b0aa931fb84431394d995472d0af2a6c2b61064d upstream.

ramoops_get_next_prz get the prz according the paramters. If it get a
uninitialized prz, access its members by following persistent_ram_old_size(prz)
will cause a NULL pointer crash.
Ex: if ftrace_size is 0, fprz will be NULL.

Fix it by return NULL in advance.

Signed-off-by: Liu ShuoX 
Acked-by: Kees Cook 
Signed-off-by: Tony Luck 
Cc: HuKeping 
Signed-off-by: Greg Kroah-Hartman

pstore: skip zero size persistent ram buffer in traverse

2015-02-06T06:35:40+00:00

commit aa9a4a1edfbd3d223af01db833da2f07850bc655 upstream.

In ramoops_pstore_read, a valid prz pointer with zero size buffer will
break traverse of all persistent ram buffers.  The latter buffer might be
lost.

Signed-off-by: Liu ShuoX 
Cc: "Zhang, Yanmin" 
Cc: Colin Cross 
Reviewed-by: Kees Cook 
Signed-off-by: Andrew Morton 
Signed-off-by: Tony Luck 
Cc: HuKeping 
Signed-off-by: Greg Kroah-Hartman

pstore: clarify clearing of _read_cnt in ramoops_context

2015-02-06T06:35:40+00:00

commit 57fd835385a043577457a385f28c08be693991bf upstream.

*_read_cnt in ramoops_context need to be cleared during pstore ->open to
support mutli times getting the records.  The patch added missed
ftrace_read_cnt clearing and removed duplicate clearing in ramoops_probe.

Signed-off-by: Liu ShuoX 
Cc: "Zhang, Yanmin" 
Cc: Colin Cross 
Cc: Kees Cook 
Signed-off-by: Andrew Morton 
Signed-off-by: Tony Luck 
Cc: HuKeping 
Signed-off-by: Greg Kroah-Hartman

pstore: d_alloc_name() doesn't return an ERR_PTR

2015-02-06T06:35:39+00:00

commit c39524e6744284452ef45480d3153bec28960c32 upstream.

d_alloc_name() returns NULL on error.  Also I changed the error code
from -ENOSPC to -ENOMEM to reflect that we were short on RAM not disk
space.

Signed-off-by: Dan Carpenter 
Acked-by: Kees Cook 
Signed-off-by: Tony Luck 
Cc: HuKeping 
Signed-off-by: Greg Kroah-Hartman

pstore: Fail to unlink if a driver has not defined pstore_erase

2015-02-06T06:35:39+00:00

commit bf2883339a33b7544b92ea465b90c3de55082032 upstream.

pstore_erase is used to erase the record from the persistent store.
So if a driver has not defined pstore_erase callback return
-EPERM instead of unlinking a file as deleting the file without
erasing its record in persistent store will give a wrong impression
to customers.

Signed-off-by: Aruna Balakrishnaiah 
Acked-by: Kees Cook 
Signed-off-by: Tony Luck 
Cc: HuKeping 
Signed-off-by: Greg Kroah-Hartman

NFSv4.1: Fix an Oops in nfs41_walk_client_list

2015-02-06T06:35:36+00:00

commit 3175e1dcec40fab1a444c010087f2068b6b04732 upstream.

If we start state recovery on a client that failed to initialise correctly,
then we are very likely to Oops.

Reported-by: "Mkrtchyan, Tigran" 
Link: http://lkml.kernel.org/r/130621862.279655.1421851650684.JavaMail.zimbra@desy.de
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

nfs: fix dio deadlock when O_DIRECT flag is flipped

2015-02-06T06:35:36+00:00

commit ee8a1a8b160a87dc3a9c81a86796aa4db85ea815 upstream.

We only support swap file calling nfs_direct_IO. However, application
might be able to get to nfs_direct_IO if it toggles O_DIRECT flag
during IO and it can deadlock because we grab inode->i_mutex in
nfs_file_direct_write(). So return 0 for such case. Then the generic
layer will fall back to buffer IO.

Signed-off-by: Peng Tao 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman