linux-stable.git/fs, branch v3.5.6

coredump: prevent double-free on an error path in core dumper

2012-10-07T15:35:55+00:00

commit f34f9d186df35e5c39163444c43b4fc6255e39c5 upstream.

In !CORE_DUMP_USE_REGSET case, if elf_note_info_init fails to allocate
memory for info->fields, it frees already allocated stuff and returns
error to its caller, fill_note_info.  Which in turn returns error to its
caller, elf_core_dump.  Which jumps to cleanup label and calls
free_note_info, which will happily try to free all info->fields again.
BOOM.

This is the fix.

Signed-off-by: Oleg Nesterov 
Signed-off-by: Denys Vlasenko 
Cc: Venu Byravarasu 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

vfs: dcache: fix deadlock in tree traversal

2012-10-07T15:35:49+00:00

commit 8110e16d42d587997bcaee0c864179e6d93603fe upstream.

IBM reported a deadlock in select_parent().  This was found to be caused
by taking rename_lock when already locked when restarting the tree
traversal.

There are two cases when the traversal needs to be restarted:

 1) concurrent d_move(); this can only happen when not already locked,
    since taking rename_lock protects against concurrent d_move().

 2) racing with final d_put() on child just at the moment of ascending
    to parent; rename_lock doesn't protect against this rare race, so it
    can happen when already locked.

Because of case 2, we need to be able to handle restarting the traversal
when rename_lock is already held.  This patch fixes all three callers of
try_to_ascend().

IBM reported that the deadlock is gone with this patch.

[ I rewrote the patch to be smaller and just do the "goto again" if the
  lock was already held, but credit goes to Miklos for the real work.
   - Linus ]

Signed-off-by: Miklos Szeredi 
Cc: Al Viro 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

NFSd: set nfsd_serv to NULL after service destruction

2012-10-02T17:40:01+00:00

commit 57c8b13e3cd0f94944c9691ce7f58e5fcef8a12d upstream.

In nfsd_destroy():

	if (destroy)
		svc_shutdown_net(nfsd_serv, net);
	svc_destroy(nfsd_server);

svc_shutdown_net(nfsd_serv, net) calls nfsd_last_thread(), which sets
nfsd_serv to NULL, causing a NULL dereference on the following line.

Signed-off-by: Stanislav Kinsbursky 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

NFSd: introduce nfsd_destroy() helper

2012-10-02T17:40:01+00:00

commit 19f7e2ca44dfc3c1b3f499fc46801f98d403500f upstream.

Signed-off-by: Stanislav Kinsbursky 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate

2012-10-02T17:39:59+00:00

[Fixed upstream as part of 0b728e1911c, but that's a much larger patch,
this is only the nfs portion backported as needed.]

Fix the following Oops in 3.5.1:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
 IP: [] nfs_lookup_revalidate+0x2d/0x480 [nfs]
 PGD 337c63067 PUD 0
 Oops: 0000 [#1] SMP
 CPU 5
 Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys

 Pid: 30431, comm: java Not tainted 3.5.1-2-default #1 Supermicro X8DTT/X8DTT
 RIP: 0010:[]  [] nfs_lookup_revalidate+0x2d/0x480 [nfs]
 RSP: 0018:ffff8801b418bd38  EFLAGS: 00010292
 RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020
 RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00
 RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed
 R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00
 R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0
 FS:  00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600)
 Stack:
  ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000
  ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0
  ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000
 Call Trace:
  [] lookup_dcache+0x80/0xe0
  [] __lookup_hash+0x23/0x90
  [] lookup_one_len+0xc5/0x100
  [] nfs_sillyrename+0xe3/0x210 [nfs]
  [] vfs_unlink.part.25+0x7f/0xe0
  [] do_unlinkat+0x1ac/0x1d0
  [] system_call_fastpath+0x16/0x1b
  [<00002b5348b5f527>] 0x2b5348b5f526
 Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30  46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89
 RIP  [] nfs_lookup_revalidate+0x2d/0x480 [nfs]
  RSP 
 CR2: 0000000000000038
 ---[ end trace 845113ed191985dd ]---

This Oops affects 3.5 kernels and older, and is due to lookup_one_len()
calling down to the dentry revalidation code with a NULL pointer
to struct nameidata.

It is fixed upstream by commit 0b728e1911c (stop passing nameidata *
to ->d_revalidate())

Reported-by: Richard Ems 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

NFS: return error from decode_getfh in decode open

2012-10-02T17:39:27+00:00

commit 01913b49cf1dc6409a07dd2a4cc6af2e77f3c410 upstream.

If decode_getfh failed, nfs4_xdr_dec_open would return 0 since the last
decode_* call must have succeeded.

Signed-off-by: Weston Andros Adamson 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

NFS: Fix a problem with the legacy binary mount code

2012-10-02T17:39:27+00:00

commit 872ece86ea5c367aa92f44689c2d01a1c767aeb3 upstream.

Apparently, am-utils is still using the legacy binary mountdata interface,
and is having trouble parsing /proc/mounts due to the 'port=' field being
incorrectly set.

The following patch should fix up the regression.

Reported-by: Marius Tolzmann 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

NFS: Fix the initialisation of the readdir 'cookieverf' array

2012-10-02T17:39:27+00:00

commit c3f52af3e03013db5237e339c817beaae5ec9e3a upstream.

When the NFS_COOKIEVERF helper macro was converted into a static
inline function in commit 99fadcd764 (nfs: convert NFS_*(inode)
helpers to static inline), we broke the initialisation of the
readdir cookies, since that depended on doing a memset with an
argument of 'sizeof(NFS_COOKIEVERF(inode))' which therefore
changed from sizeof(be32 cookieverf[2]) to sizeof(be32 *).

At this point, NFS_COOKIEVERF seems to be more of an obfuscation
than a helper, so the best thing would be to just get rid of it.

Also see: https://bugzilla.kernel.org/show_bug.cgi?id=46881

Reported-by: Andi Kleen 
Reported-by: David Binderman 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

cifs: fix return value in cifsConvertToUTF16

2012-10-02T17:39:22+00:00

commit c73f693989d7a7d99ec66a7065295a0c93d0b127 upstream.

This function returns the wrong value, which causes the callers to get
the length of the resulting pathname wrong when it contains non-ASCII
characters.

This seems to fix https://bugzilla.samba.org/show_bug.cgi?id=6767

Reported-by: Baldvin Kovacs 
Reported-and-Tested-by: Nicolas Lefebvre 
Signed-off-by: Jeff Layton 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

fs/proc: fix potential unregister_sysctl_table hang

2012-10-02T17:39:07+00:00

commit 6bf6104573482570f7103d3e5ddf9574db43a363 upstream.

The unregister_sysctl_table() function hangs if all references to its
ctl_table_header structure are not dropped.

This can happen sometimes because of a leak in proc_sys_lookup():
proc_sys_lookup() gets a reference to the table via lookup_entry(), but
it does not release it when a subsequent call to sysctl_follow_link()
fails.

This patch fixes this leak by making sure the reference is always
dropped on return.

See also commit 076c3eed2c31 ("sysctl: Rewrite proc_sys_lookup
introducing find_entry and lookup_entry") which reorganized this code in
3.4.

Tested in Linux 3.4.4.

Signed-off-by: Francesco Ruggeri 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman