linux-stable.git/fs/ext4/super.c, branch linux-3.3.y

ext4: address scalability issue by removing extent cache statistics

2012-04-22T22:38:56+00:00

commit 9cd70b347e9761ea2d2ac3d758c529a48a8193e6 upstream.

Andi Kleen and Tim Chen have reported that under certain circumstances
the extent cache statistics are causing scalability problems due to
cache line bounces.

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'for_linus' into for_linus_merged

2012-01-10T16:54:07+00:00

Conflicts:
	fs/ext4/ioctl.c

ext4: fix undefined behavior in ext4_fill_flex_info()

2012-01-10T16:51:10+00:00

Commit 503358ae01b70ce6909d19dd01287093f6b6271c ("ext4: avoid divide by
zero when trying to mount a corrupted file system") fixes CVE-2009-4307
by performing a sanity check on s_log_groups_per_flex, since it can be
set to a bogus value by an attacker.

	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
	groups_per_flex = 1 << sbi->s_log_groups_per_flex;

	if (groups_per_flex < 2) { ... }

This patch fixes two potential issues in the previous commit.

1) The sanity check might only work on architectures like PowerPC.
On x86, 5 bits are used for the shifting amount.  That means, given a
large s_log_groups_per_flex value like 36, groups_per_flex = 1 << 36
is essentially 1 << 4 = 16, rather than 0.  This will bypass the check,
leaving s_log_groups_per_flex and groups_per_flex inconsistent.

2) The sanity check relies on undefined behavior, i.e., oversized shift.
A standard-confirming C compiler could rewrite the check in unexpected
ways.  Consider the following equivalent form, assuming groups_per_flex
is unsigned for simplicity.

	groups_per_flex = 1 << sbi->s_log_groups_per_flex;
	if (groups_per_flex == 0 || groups_per_flex == 1) {

We compile the code snippet using Clang 3.0 and GCC 4.6.  Clang will
completely optimize away the check groups_per_flex == 0, leaving the
patched code as vulnerable as the original.  GCC keeps the check, but
there is no guarantee that future versions will do the same.

Signed-off-by: Xi Wang 
Signed-off-by: "Theodore Ts'o" 
Cc: stable@vger.kernel.org

ext4: fix failure exits

2012-01-09T20:57:20+00:00

a) leaking root dentry is bad
b) in case of failed ext4_mb_init() we don't want to do ext4_mb_release()
c) OTOH, in the same case we *do* want ext4_ext_release()

Signed-off-by: Al Viro

Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2012-01-08T21:10:57+00:00

* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
  PM / Hibernate: Implement compat_ioctl for /dev/snapshot
  PM / Freezer: fix return value of freezable_schedule_timeout_killable()
  PM / shmobile: Allow the A4R domain to be turned off at run time
  PM / input / touchscreen: Make st1232 use device PM QoS constraints
  PM / QoS: Introduce dev_pm_qos_add_ancestor_request()
  PM / shmobile: Remove the stay_on flag from SH7372's PM domains
  PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume
  PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
  PM: Drop generic_subsys_pm_ops
  PM / Sleep: Remove forward-only callbacks from AMBA bus type
  PM / Sleep: Remove forward-only callbacks from platform bus type
  PM: Run the driver callback directly if the subsystem one is not there
  PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
  PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.
  PM / Sleep: Merge internal functions in generic_ops.c
  PM / Sleep: Simplify generic system suspend callbacks
  PM / Hibernate: Remove deprecated hibernation snapshot ioctls
  PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
  ARM: S3C64XX: Implement basic power domain support
  PM / shmobile: Use common always on power domain governor
  ...

Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused
XBT_FORCE_SLEEP bit

vfs: switch ->show_options() to struct dentry *

2012-01-07T04:19:54+00:00

Signed-off-by: Al Viro

vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb

2012-01-07T04:16:53+00:00

Signed-off-by: Al Viro

ext4: Report max_batch_time option correctly

2012-01-05T02:22:51+00:00

Currently the value reported for max_batch_time is really the
value of min_batch_time.

Reported-by: Russell Coker 
Signed-off-by: Ben Hutchings

vfs: fix the stupidity with i_dentry in inode destructors

2012-01-04T03:52:40+00:00

Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...

Signed-off-by: Al Viro

Merge branch 'master' into pm-sleep

2011-12-21T20:59:45+00:00

* master: (848 commits)
  SELinux: Fix RCU deref check warning in sel_netport_insert()
  binary_sysctl(): fix memory leak
  mm/vmalloc.c: remove static declaration of va from __get_vm_area_node
  ipmi_watchdog: restore settings when BMC reset
  oom: fix integer overflow of points in oom_badness
  memcg: keep root group unchanged if creation fails
  nilfs2: potential integer overflow in nilfs_ioctl_clean_segments()
  nilfs2: unbreak compat ioctl
  cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask
  evm: prevent racing during tfm allocation
  evm: key must be set once during initialization
  mmc: vub300: fix type of firmware_rom_wait_states module parameter
  Revert "mmc: enable runtime PM by default"
  mmc: sdhci: remove "state" argument from sdhci_suspend_host
  x86, dumpstack: Fix code bytes breakage due to missing KERN_CONT
  IB/qib: Correct sense on freectxts increment and decrement
  RDMA/cma: Verify private data length
  cgroups: fix a css_set not found bug in cgroup_attach_proc
  oprofile: Fix uninitialized memory access when writing to writing to oprofilefs
  Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel"
  ...

Conflicts:
	kernel/cgroup_freezer.c