linux.git/fs, branch v3.11-rc4 Linux kernel source tree ocfs2/refcounttree: add the missing NULL check of the return value of find_or_create_page() 2013-07-31T21:41:02+00:00 Gu Zheng guz.fnst@cn.fujitsu.com 2013-07-31T20:53:29+00:00 62c610460d73fcfa5637cb497c6923ef1c42b12d Add the missing NULL check of the return value of find_or_create_page() in function ocfs2_duplicate_clusters_by_page(). [akpm@linux-foundation.org: fix layout, per Joel] Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Acked-by: 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> 
Add the missing NULL check of the return value of find_or_create_page() in
function ocfs2_duplicate_clusters_by_page().

[akpm@linux-foundation.org: fix layout, per Joel]
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Acked-by: 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>
Merge tag 'for-linus-v3.11-rc3' of git://oss.sgi.com/xfs/xfs 2013-07-26T18:22:54+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-07-26T18:22:54+00:00 6c4155a9cd6bd07d3cb70ca5eeb6f2751de0931c Pull xfs fix from Ben Myers: "Fix for regression in commit cca9f93a52d2 ("xfs: don't do IO when creating an new inode"), recovery causing filesystem corruption after a crash" * tag 'for-linus-v3.11-rc3' of git://oss.sgi.com/xfs/xfs: xfs: di_flushiter considered harmful 
Pull xfs fix from Ben Myers:
 "Fix for regression in commit cca9f93a52d2 ("xfs: don't do IO when
  creating an new inode"), recovery causing filesystem corruption after
  a crash"

* tag 'for-linus-v3.11-rc3' of git://oss.sgi.com/xfs/xfs:
  xfs: di_flushiter considered harmful
Merge branch 'for-3.11' of git://linux-nfs.org/~bfields/linux 2013-07-26T18:21:43+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-07-26T18:21:43+00:00 f315cf5e02d9910b7be893f5b5afdcc2e49d352d Pull nfsd fix from Bruce Fields: "One more nfsd bugfix for 3.11" * 'for-3.11' of git://linux-nfs.org/~bfields/linux: nfsd: nfsd_open: when dentry_open returns an error do not propagate as struct file 
Pull nfsd fix from Bruce Fields:
 "One more nfsd bugfix for 3.11"

* 'for-3.11' of git://linux-nfs.org/~bfields/linux:
  nfsd: nfsd_open: when dentry_open returns an error do not propagate as struct file
xfs: di_flushiter considered harmful 2013-07-25T15:41:42+00:00 Dave Chinner dchinner@redhat.com 2013-07-24T05:47:30+00:00 e1b4271ac261b290fdab51446996fb13e68a57be When we made all inode updates transactional, we no longer needed the log recovery detection for inodes being newer on disk than the transaction being replayed - it was redundant as replay of the log would always result in the latest version of the inode would be on disk. It was redundant, but left in place because it wasn't considered to be a problem. However, with the new "don't read inodes on create" optimisation, flushiter has come back to bite us. Essentially, the optimisation made always initialises flushiter to zero in the create transaction, and so if we then crash and run recovery and the inode already on disk has a non-zero flushiter it will skip recovery of that inode. As a result, log recovery does the wrong thing and we end up with a corrupt filesystem. Because we have to support old kernel to new kernel upgrades, we can't just get rid of the flushiter support in log recovery as we might be upgrading from a kernel that doesn't have fully transactional inode updates. Unfortunately, for v4 superblocks there is no way to guarantee that log recovery knows about this fact. We cannot add a new inode format flag to say it's a "special inode create" because it won't be understood by older kernels and so recovery could do the wrong thing on downgrade. We cannot specially detect the combination of zero mode/non-zero flushiter on disk to non-zero mode, zero flushiter in the log item during recovery because wrapping of the flushiter can result in false detection. Hence that makes this "don't use flushiter" optimisation limited to a disk format that guarantees that we don't need it. And that means the only fix here is to limit the "no read IO on create" optimisation to version 5 superblocks.... Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com> (cherry picked from commit e60896d8f2b81412421953e14d3feb14177edb56) 
When we made all inode updates transactional, we no longer needed
the log recovery detection for inodes being newer on disk than the
transaction being replayed - it was redundant as replay of the log
would always result in the latest version of the inode would be on
disk. It was redundant, but left in place because it wasn't
considered to be a problem.

However, with the new "don't read inodes on create" optimisation,
flushiter has come back to bite us. Essentially, the optimisation
made always initialises flushiter to zero in the create transaction,
and so if we then crash and run recovery and the inode already on
disk has a non-zero flushiter it will skip recovery of that inode.
As a result, log recovery does the wrong thing and we end up with a
corrupt filesystem.

Because we have to support old kernel to new kernel upgrades, we
can't just get rid of the flushiter support in log recovery as we
might be upgrading from a kernel that doesn't have fully transactional
inode updates.  Unfortunately, for v4 superblocks there is no way to
guarantee that log recovery knows about this fact.

We cannot add a new inode format flag to say it's a "special inode
create" because it won't be understood by older kernels and so
recovery could do the wrong thing on downgrade. We cannot specially
detect the combination of zero mode/non-zero flushiter on disk to
non-zero mode, zero flushiter in the log item during recovery
because wrapping of the flushiter can result in false detection.

Hence that makes this "don't use flushiter" optimisation limited to
a disk format that guarantees that we don't need it. And that means
the only fix here is to limit the "no read IO on create"
optimisation to version 5 superblocks....

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit e60896d8f2b81412421953e14d3feb14177edb56)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse 2013-07-23T21:37:04+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-07-23T21:37:04+00:00 55c62960b0a7f378a9ab5237a2f9cf02dfe95a36 Pull fuse bugfixes from Miklos Szeredi: "These are bugfixes and a cleanup to the "readdirplus" feature" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: readdirplus: cleanup fuse: readdirplus: change attributes once fuse: readdirplus: fix instantiate fuse: readdirplus: sanity checks fuse: readdirplus: fix dentry leak 
Pull fuse bugfixes from Miklos Szeredi:
 "These are bugfixes and a cleanup to the "readdirplus" feature"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: readdirplus: cleanup
  fuse: readdirplus: change attributes once
  fuse: readdirplus: fix instantiate
  fuse: readdirplus: sanity checks
  fuse: readdirplus: fix dentry leak
NFSv4: Fix brainfart in attribute length calculation 2013-07-23T21:24:59+00:00 Trond Myklebust Trond.Myklebust@netapp.com 2013-07-23T16:53:39+00:00 4f3cc4809a98a165a9708b72b47de71643797bbd The calculation of the attribute length was 4 bytes off. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Tested-by: Andre Heider <a.heider@gmail.com> Reported-and-tested-by: Henrik Rydberg <rydberg@euromail.se> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
The calculation of the attribute length was 4 bytes off.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Andre Heider <a.heider@gmail.com>
Reported-and-tested-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nfsd: nfsd_open: when dentry_open returns an error do not propagate as struct file 2013-07-23T16:15:32+00:00 Harshula Jayasuriya harshula@redhat.com 2013-07-23T04:21:35+00:00 e4daf1ffbe6cc3b12aab4d604e627829e93e9914 The following call chain: ------------------------------------------------------------ nfs4_get_vfs_file - nfsd_open - dentry_open - do_dentry_open - __get_file_write_access - get_write_access - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY; ------------------------------------------------------------ can result in the following state: ------------------------------------------------------------ struct nfs4_file { ... fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0}, fi_access = {{ counter = 0x1 }, { counter = 0x0 }}, ... ------------------------------------------------------------ 1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is NULL, hence nfsd_open() is called where we get status set to an error and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented. 2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented. Thus we leave a landmine in the form of the nfs4_file data structure in an incorrect state. 3) Eventually, when __nfs4_file_put_access() is called it finds fi_access[O_WRONLY] being non-zero, it decrements it and calls nfs4_file_put_fd() which tries to fput -ETXTBSY. ------------------------------------------------------------ ... [exception RIP: fput+0x9] RIP: ffffffff81177fa9 RSP: ffff88062e365c90 RFLAGS: 00010282 RAX: ffff880c2b3d99cc RBX: ffff880c2b3d9978 RCX: 0000000000000002 RDX: dead000000100101 RSI: 0000000000000001 RDI: ffffffffffffffe6 RBP: ffff88062e365c90 R8: ffff88041fe797d8 R9: ffff88062e365d58 R10: 0000000000000008 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000007 R14: 0000000000000000 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd] #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd] #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd] #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd] #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd] #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd] #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd] #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc] #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc] #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd] #19 [ffff88062e365ee8] kthread at ffffffff81090886 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a ------------------------------------------------------------ Cc: stable@vger.kernel.org Signed-off-by: Harshula Jayasuriya <harshula@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> 
The following call chain:
------------------------------------------------------------
nfs4_get_vfs_file
- nfsd_open
  - dentry_open
    - do_dentry_open
      - __get_file_write_access
        - get_write_access
          - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
------------------------------------------------------------

can result in the following state:
------------------------------------------------------------
struct nfs4_file {
...
  fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0},
  fi_access = {{
      counter = 0x1
    }, {
      counter = 0x0
    }},
...
------------------------------------------------------------

1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NULL, hence nfsd_open() is called where we get status set to an error
and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach
nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented.

2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but
nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented.
Thus we leave a landmine in the form of the nfs4_file data structure in
an incorrect state.

3) Eventually, when __nfs4_file_put_access() is called it finds
fi_access[O_WRONLY] being non-zero, it decrements it and calls
nfs4_file_put_fd() which tries to fput -ETXTBSY.
------------------------------------------------------------
...
     [exception RIP: fput+0x9]
     RIP: ffffffff81177fa9  RSP: ffff88062e365c90  RFLAGS: 00010282
     RAX: ffff880c2b3d99cc  RBX: ffff880c2b3d9978  RCX: 0000000000000002
     RDX: dead000000100101  RSI: 0000000000000001  RDI: ffffffffffffffe6
     RBP: ffff88062e365c90   R8: ffff88041fe797d8   R9: ffff88062e365d58
     R10: 0000000000000008  R11: 0000000000000000  R12: 0000000000000001
     R13: 0000000000000007  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd]
 #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd]
 #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd]
 #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd]
 #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd]
 #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd]
 #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd]
 #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc]
 #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc]
 #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd]
 #19 [ffff88062e365ee8] kthread at ffffffff81090886
 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a
------------------------------------------------------------

Cc: stable@vger.kernel.org
Signed-off-by: Harshula Jayasuriya <harshula@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
ext3: fix a BUG when opening a file with O_TMPFILE flag 2013-07-21T02:03:20+00:00 Zheng Liu wenqing.lz@taobao.com 2013-07-21T02:03:20+00:00 dda5690defe4af62ee120f055e98e40d97e4c760 When we try to open a file with O_TMPFILE flag, we will trigger a bug. The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and this check always fails because we set ->i_nlink = 1 in inode_init_always(). We can use the following program to trigger it: int main(int argc, char *argv[]) { int fd; fd = open(argv[1], O_TMPFILE, 0666); if (fd < 0) { perror("open "); return -1; } close(fd); return 0; } The oops message looks like this: kernel: kernel BUG at fs/ext3/namei.c:1992! kernel: invalid opcode: 0000 [#1] SMP kernel: Modules linked in: ext4 jbd2 crc16 cpufreq_ondemand ipv6 dm_mirror dm_region_hash dm_log dm_mod parport_pc parport serio_raw sg dcdbas pcspkr i2c_i801 ehci_pci ehci_hcd button acpi_cpufreq mperf e1000e ptp pps_core ttm drm_kms_helper drm hwmon i2c_algo_bit i2c_core ext3 jbd sd_mod ahci libahci libata scsi_mod uhci_hcd kernel: CPU: 0 PID: 2882 Comm: tst_tmpfile Not tainted 3.11.0-rc1+ #4 kernel: Hardware name: Dell Inc. OptiPlex 780 /0V4W66, BIOS A05 08/11/2010 kernel: task: ffff880112d30050 ti: ffff8801124d4000 task.ti: ffff8801124d4000 kernel: RIP: 0010:[<ffffffffa00db5ae>] [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3] kernel: RSP: 0018:ffff8801124d5cc8 EFLAGS: 00010202 kernel: RAX: 0000000000000000 RBX: ffff880111510128 RCX: ffff8801114683a0 kernel: RDX: 0000000000000000 RSI: ffff880111510128 RDI: ffff88010fcf65a8 kernel: RBP: ffff8801124d5d18 R08: 0080000000000000 R09: ffffffffa00d3b7f kernel: R10: ffff8801114683a0 R11: ffff8801032a2558 R12: 0000000000000000 kernel: R13: ffff88010fcf6800 R14: ffff8801032a2558 R15: ffff8801115100d8 kernel: FS: 00007f5d172b5700(0000) GS:ffff880117c00000(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b kernel: CR2: 00007f5d16df15d0 CR3: 0000000110b1d000 CR4: 00000000000407f0 kernel: Stack: kernel: 000000000000000c ffff8801048a7dc8 ffff8801114685a8 ffffffffa00b80d7 kernel: ffff8801124d5e38 ffff8801032a2558 ffff88010ce24d68 0000000000000000 kernel: ffff88011146b300 ffff8801124d5d44 ffff8801124d5d78 ffffffffa00db7e1 kernel: Call Trace: kernel: [<ffffffffa00b80d7>] ? journal_start+0x8c/0xbd [jbd] kernel: [<ffffffffa00db7e1>] ext3_tmpfile+0xb2/0x13b [ext3] kernel: [<ffffffff821076f8>] path_openat+0x11f/0x5e7 kernel: [<ffffffff821c86b4>] ? list_del+0x11/0x30 kernel: [<ffffffff82065fa2>] ? __dequeue_entity+0x33/0x38 kernel: [<ffffffff82107cd5>] do_filp_open+0x3f/0x8d kernel: [<ffffffff82112532>] ? __alloc_fd+0x50/0x102 kernel: [<ffffffff820f9296>] do_sys_open+0x13b/0x1cd kernel: [<ffffffff820f935c>] SyS_open+0x1e/0x20 kernel: [<ffffffff82398c02>] system_call_fastpath+0x16/0x1b kernel: Code: 39 c7 0f 85 67 01 00 00 0f b7 03 25 00 f0 00 00 3d 00 40 00 00 74 18 3d 00 80 00 00 74 11 3d 00 a0 00 00 74 0a 83 7b 48 00 74 04 <0f> 0b eb fe 49 8b 85 50 03 00 00 4c 89 f6 48 c7 c7 c0 99 0e a0 kernel: RIP [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3] kernel: RSP <ffff8801124d5cc8> Here we couldn't call clear_nlink() directly because in d_tmpfile() we will call inode_dec_link_count() to decrease ->i_nlink. So this commit tries to call d_tmpfile() before ext4_orphan_add() to fix this problem. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> 
When we try to open a file with O_TMPFILE flag, we will trigger a bug.
The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and
this check always fails because we set ->i_nlink = 1 in
inode_init_always().  We can use the following program to trigger it:

int main(int argc, char *argv[])
{
	int fd;

	fd = open(argv[1], O_TMPFILE, 0666);
	if (fd < 0) {
		perror("open ");
		return -1;
	}
	close(fd);
	return 0;
}

The oops message looks like this:

kernel: kernel BUG at fs/ext3/namei.c:1992!
kernel: invalid opcode: 0000 [#1] SMP
kernel: Modules linked in: ext4 jbd2 crc16 cpufreq_ondemand ipv6 dm_mirror dm_region_hash dm_log dm_mod parport_pc parport serio_raw sg dcdbas pcspkr i2c_i801 ehci_pci ehci_hcd button acpi_cpufreq mperf e1000e ptp pps_core ttm drm_kms_helper drm hwmon i2c_algo_bit i2c_core ext3 jbd sd_mod ahci libahci libata scsi_mod uhci_hcd
kernel: CPU: 0 PID: 2882 Comm: tst_tmpfile Not tainted 3.11.0-rc1+ #4
kernel: Hardware name: Dell Inc. OptiPlex 780 /0V4W66, BIOS A05 08/11/2010
kernel: task: ffff880112d30050 ti: ffff8801124d4000 task.ti: ffff8801124d4000
kernel: RIP: 0010:[<ffffffffa00db5ae>] [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3]
kernel: RSP: 0018:ffff8801124d5cc8  EFLAGS: 00010202
kernel: RAX: 0000000000000000 RBX: ffff880111510128 RCX: ffff8801114683a0
kernel: RDX: 0000000000000000 RSI: ffff880111510128 RDI: ffff88010fcf65a8
kernel: RBP: ffff8801124d5d18 R08: 0080000000000000 R09: ffffffffa00d3b7f
kernel: R10: ffff8801114683a0 R11: ffff8801032a2558 R12: 0000000000000000
kernel: R13: ffff88010fcf6800 R14: ffff8801032a2558 R15: ffff8801115100d8
kernel: FS:  00007f5d172b5700(0000) GS:ffff880117c00000(0000) knlGS:0000000000000000
kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
kernel: CR2: 00007f5d16df15d0 CR3: 0000000110b1d000 CR4: 00000000000407f0
kernel: Stack:
kernel: 000000000000000c ffff8801048a7dc8 ffff8801114685a8 ffffffffa00b80d7
kernel: ffff8801124d5e38 ffff8801032a2558 ffff88010ce24d68 0000000000000000
kernel: ffff88011146b300 ffff8801124d5d44 ffff8801124d5d78 ffffffffa00db7e1
kernel: Call Trace:
kernel: [<ffffffffa00b80d7>] ? journal_start+0x8c/0xbd [jbd]
kernel: [<ffffffffa00db7e1>] ext3_tmpfile+0xb2/0x13b [ext3]
kernel: [<ffffffff821076f8>] path_openat+0x11f/0x5e7
kernel: [<ffffffff821c86b4>] ? list_del+0x11/0x30
kernel: [<ffffffff82065fa2>] ?  __dequeue_entity+0x33/0x38
kernel: [<ffffffff82107cd5>] do_filp_open+0x3f/0x8d
kernel: [<ffffffff82112532>] ? __alloc_fd+0x50/0x102
kernel: [<ffffffff820f9296>] do_sys_open+0x13b/0x1cd
kernel: [<ffffffff820f935c>] SyS_open+0x1e/0x20
kernel: [<ffffffff82398c02>] system_call_fastpath+0x16/0x1b
kernel: Code: 39 c7 0f 85 67 01 00 00 0f b7 03 25 00 f0 00 00 3d 00 40 00 00 74 18 3d 00 80 00 00 74 11 3d 00 a0 00 00 74 0a 83 7b 48 00 74 04 <0f> 0b eb fe 49 8b 85 50 03 00 00 4c 89 f6 48 c7 c7 c0 99 0e a0
kernel: RIP  [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3]
kernel: RSP <ffff8801124d5cc8>

Here we couldn't call clear_nlink() directly because in d_tmpfile() we
will call inode_dec_link_count() to decrease ->i_nlink.  So this commit
tries to call d_tmpfile() before ext4_orphan_add() to fix this problem.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
ext4: fix a BUG when opening a file with O_TMPFILE flag 2013-07-21T01:58:38+00:00 Zheng Liu wenqing.lz@taobao.com 2013-07-21T01:58:38+00:00 e94bd3490f4ef342801cfc76b33d8baf9ccc9437 When we try to open a file with O_TMPFILE flag, we will trigger a bug. The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and this check always fails because we set ->i_nlink = 1 in inode_init_always(). We can use the following program to trigger it: int main(int argc, char *argv[]) { int fd; fd = open(argv[1], O_TMPFILE, 0666); if (fd < 0) { perror("open "); return -1; } close(fd); return 0; } The oops message looks like this: kernel BUG at fs/ext4/namei.c:2572! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: dlci bridge stp hidp cmtp kernelcapi l2tp_ppp l2tp_netlink l2tp_core sctp libcrc32c rfcomm tun fuse nfnetli nk can_raw ipt_ULOG can_bcm x25 scsi_transport_iscsi ipx p8023 p8022 appletalk phonet psnap vmw_vsock_vmci_transport af_key vmw_vmci rose vsock atm can netrom ax25 af_rxrpc ir da pppoe pppox ppp_generic slhc bluetooth nfc rfkill rds caif_socket caif crc_ccitt af_802154 llc2 llc snd_hda_codec_realtek snd_hda_intel snd_hda_codec serio_raw snd_pcm pcsp kr edac_core snd_page_alloc snd_timer snd soundcore r8169 mii sr_mod cdrom pata_atiixp radeon backlight drm_kms_helper ttm CPU: 1 PID: 1812571 Comm: trinity-child2 Not tainted 3.11.0-rc1+ #12 Hardware name: Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H, BIOS F12a 04/23/2010 task: ffff88007dfe69a0 ti: ffff88010f7b6000 task.ti: ffff88010f7b6000 RIP: 0010:[<ffffffff8125ce69>] [<ffffffff8125ce69>] ext4_orphan_add+0x299/0x2b0 RSP: 0018:ffff88010f7b7cf8 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff8800966d3020 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88007dfe70b8 RDI: 0000000000000001 RBP: ffff88010f7b7d40 R08: ffff880126a3c4e0 R09: ffff88010f7b7ca0 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801271fd668 R13: ffff8800966d2f78 R14: ffff88011d7089f0 R15: ffff88007dfe69a0 FS: 00007f70441a3740(0000) GS:ffff88012a800000(0000) knlGS:00000000f77c96c0 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000002834000 CR3: 0000000107964000 CR4: 00000000000007e0 DR0: 0000000000780000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Stack: 0000000000002000 00000020810b6dde 0000000000000000 ffff88011d46db00 ffff8800966d3020 ffff88011d7089f0 ffff88009c7f4c10 ffff88010f7b7f2c ffff88007dfe69a0 ffff88010f7b7da8 ffffffff8125cfac ffff880100000004 Call Trace: [<ffffffff8125cfac>] ext4_tmpfile+0x12c/0x180 [<ffffffff811cba78>] path_openat+0x238/0x700 [<ffffffff8100afc4>] ? native_sched_clock+0x24/0x80 [<ffffffff811cc647>] do_filp_open+0x47/0xa0 [<ffffffff811db73f>] ? __alloc_fd+0xaf/0x200 [<ffffffff811ba2e4>] do_sys_open+0x124/0x210 [<ffffffff81010725>] ? syscall_trace_enter+0x25/0x290 [<ffffffff811ba3ee>] SyS_open+0x1e/0x20 [<ffffffff816ca8d4>] tracesys+0xdd/0xe2 [<ffffffff81001001>] ? start_thread_common.constprop.6+0x1/0xa0 Code: 04 00 00 00 89 04 24 31 c0 e8 c4 77 04 00 e9 43 fe ff ff 66 25 00 d0 66 3d 00 80 0f 84 0e fe ff ff 83 7b 48 00 0f 84 04 fe ff ff <0f> 0b 49 8b 8c 24 50 07 00 00 e9 88 fe ff ff 0f 1f 84 00 00 00 Here we couldn't call clear_nlink() directly because in d_tmpfile() we will call inode_dec_link_count() to decrease ->i_nlink. So this commit tries to call d_tmpfile() before ext4_orphan_add() to fix this problem. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Tested-by: Darrick J. Wong <darrick.wong@oracle.com> Tested-by: Dave Jones <davej@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Acked-by: Al Viro <viro@zeniv.linux.org.uk> 
When we try to open a file with O_TMPFILE flag, we will trigger a bug.
The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and
this check always fails because we set ->i_nlink = 1 in
inode_init_always().  We can use the following program to trigger it:

int main(int argc, char *argv[])
{
	int fd;

	fd = open(argv[1], O_TMPFILE, 0666);
	if (fd < 0) {
		perror("open ");
		return -1;
	}
	close(fd);
	return 0;
}

The oops message looks like this:

kernel BUG at fs/ext4/namei.c:2572!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in: dlci bridge stp hidp cmtp kernelcapi l2tp_ppp l2tp_netlink l2tp_core sctp libcrc32c rfcomm tun fuse nfnetli
nk can_raw ipt_ULOG can_bcm x25 scsi_transport_iscsi ipx p8023 p8022 appletalk phonet psnap vmw_vsock_vmci_transport af_key vmw_vmci rose vsock atm can netrom ax25 af_rxrpc ir
da pppoe pppox ppp_generic slhc bluetooth nfc rfkill rds caif_socket caif crc_ccitt af_802154 llc2 llc snd_hda_codec_realtek snd_hda_intel snd_hda_codec serio_raw snd_pcm pcsp
kr edac_core snd_page_alloc snd_timer snd soundcore r8169 mii sr_mod cdrom pata_atiixp radeon backlight drm_kms_helper ttm
CPU: 1 PID: 1812571 Comm: trinity-child2 Not tainted 3.11.0-rc1+ #12
Hardware name: Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H, BIOS F12a 04/23/2010
task: ffff88007dfe69a0 ti: ffff88010f7b6000 task.ti: ffff88010f7b6000
RIP: 0010:[<ffffffff8125ce69>]  [<ffffffff8125ce69>] ext4_orphan_add+0x299/0x2b0
RSP: 0018:ffff88010f7b7cf8  EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff8800966d3020 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88007dfe70b8 RDI: 0000000000000001
RBP: ffff88010f7b7d40 R08: ffff880126a3c4e0 R09: ffff88010f7b7ca0
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801271fd668
R13: ffff8800966d2f78 R14: ffff88011d7089f0 R15: ffff88007dfe69a0
FS:  00007f70441a3740(0000) GS:ffff88012a800000(0000) knlGS:00000000f77c96c0
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000002834000 CR3: 0000000107964000 CR4: 00000000000007e0
DR0: 0000000000780000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Stack:
 0000000000002000 00000020810b6dde 0000000000000000 ffff88011d46db00
 ffff8800966d3020 ffff88011d7089f0 ffff88009c7f4c10 ffff88010f7b7f2c
 ffff88007dfe69a0 ffff88010f7b7da8 ffffffff8125cfac ffff880100000004
Call Trace:
 [<ffffffff8125cfac>] ext4_tmpfile+0x12c/0x180
 [<ffffffff811cba78>] path_openat+0x238/0x700
 [<ffffffff8100afc4>] ? native_sched_clock+0x24/0x80
 [<ffffffff811cc647>] do_filp_open+0x47/0xa0
 [<ffffffff811db73f>] ? __alloc_fd+0xaf/0x200
 [<ffffffff811ba2e4>] do_sys_open+0x124/0x210
 [<ffffffff81010725>] ? syscall_trace_enter+0x25/0x290
 [<ffffffff811ba3ee>] SyS_open+0x1e/0x20
 [<ffffffff816ca8d4>] tracesys+0xdd/0xe2
 [<ffffffff81001001>] ? start_thread_common.constprop.6+0x1/0xa0
Code: 04 00 00 00 89 04 24 31 c0 e8 c4 77 04 00 e9 43 fe ff ff 66 25 00 d0 66 3d 00 80 0f 84 0e fe ff ff 83 7b 48 00 0f 84 04 fe ff ff <0f> 0b 49 8b 8c 24 50 07 00 00 e9 88 fe ff ff 0f 1f 84 00 00 00

Here we couldn't call clear_nlink() directly because in d_tmpfile() we
will call inode_dec_link_count() to decrease ->i_nlink.  So this commit
tries to call d_tmpfile() before ext4_orphan_add() to fix this problem.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Tested-by: Darrick J. Wong <darrick.wong@oracle.com>
Tested-by: Dave Jones <davej@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-07-20T17:50:01+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-07-20T17:50:01+00:00 36231d255b8df9cb4698e9a3902c16067d5c1398 Pull vfs fixes from Al Viro: "The sget() one is a long-standing bug and will need to go into -stable (in fact, it had been originally caught in RHEL6), the other two are 3.11-only" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: constify dentry parameter in d_count() livelock avoidance in sget() allow O_TMPFILE to work with O_WRONLY 
Pull vfs fixes from Al Viro:
 "The sget() one is a long-standing bug and will need to go into -stable
  (in fact, it had been originally caught in RHEL6), the other two are
  3.11-only"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: constify dentry parameter in d_count()
  livelock avoidance in sget()
  allow O_TMPFILE to work with O_WRONLY