3.14.2-stable review

This is the start of the stable review cycle for the 3.14.2 release. There are 33 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let me know.

Responses should be made by Sat Apr 26 21:44:12 UTC 2014. Anything received after that time might be too late.

The whole patch series can be found in one patch at:

	kernel.org/pub/linux/kernel/v3.0/stable-review/patch-3.14.2-rc1.gz

and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <[email protected]>

    Linux 3.14.2-rc1

Oleg Nesterov <[email protected]>
exit: call disassociate_ctty() before exit_task_namespaces()

Oleg Nesterov <[email protected]>

    wait: fix reparent_leader() vs EXIT_DEAD->EXIT_ZOMBIE race

Li Zefan <[email protected]>
jffs2: remove from wait queue after schedule()

Li Zefan <[email protected]>
jffs2: avoid soft-lockup in jffs2_reserve_space_gc()

Ajesh Kunhipurayil Vijayan <[email protected]>
jffs2: Fix crash due to truncation of csize

Kamlakant Patel <[email protected]>
jffs2: Fix segmentation fault found in stress test

Dan Carpenter <[email protected]>
fs: NULL dereference in posix_acl_to_xattr()

Eric Whitney <[email protected]>
ext4: fix premature freeing of partial clusters split across leaf blocks

Eric Whitney <[email protected]>
ext4: fix partial cluster handling for bigalloc file systems

Eric Whitney <[email protected]>
ext4: fix error return from ext4_ext_handle_uninitialized_extents()

Josef Bacik <[email protected]>
Btrfs: check for an extent_op on the locked ref

Josef Bacik <[email protected]>
Btrfs: fix deadlock with nested trans handles

Hidetoshi Seto <[email protected]>
Btrfs: skip submitting barrier for missing device

Mark Tinguely <[email protected]>
xfs: fix directory hash ordering bug

Jan Kara <[email protected]>
bdi: avoid oops on device removal

Derek Basehore <[email protected]>
backing_dev: fix hung task on sync

Roberto Sassu <[email protected]>
ima: restore the original behavior for sending data with ima template

Claudio Takahasi <[email protected]>
Bluetooth: Fix removing Long Term Key

Oleg Nesterov <[email protected]>

    pid_namespace: pidns_get() should check task_active_pid_ns() != NULL

Alan Stern <[email protected]>
SCSI: sd: don't fail if the device doesn't recognize SYNCHRONIZE CACHE

Peter Hurley <[email protected]>
tty: Fix low_latency BUG

Hannes Reinecke <[email protected]>
tty: Set correct tty name in 'active' sysfs attribute

Tejun Heo <[email protected]>
kernfs: protect lazy kernfs_iattrs allocation with mutex

Richard Cochran <[email protected]>
kernfs: fix off by one error.

Ian Abbott <[email protected]>
staging: comedi: fix circular locking dependency in comedi_mmap()

Ian Abbott <[email protected]>
staging: comedi: 8255_pci: initialize MITE data window

Lan Tianyu <[email protected]>
ACPI / button: Add ACPI Button event via netlink routine

Mohit Kumar <[email protected]>
PCI: designware: Fix iATU programming for cfg1, io and mem viewport

Mohit Kumar <[email protected]>
PCI: designware: Fix RC BAR to be single 64-bit non-prefetchable memory BAR

Neil Horman <[email protected]>
x86: Adjust irq remapping quirk for older revisions of 5500/5520 chipsets

Jason Wang <[email protected]>
x86, hyperv: Bypass the timer_irq_works() check

Jiri Slaby <[email protected]>
Char: ipmi_bt_sm, fix infinite loop

Mikulas Patocka <[email protected]>
user namespace: fix incorrect memory barriers

-------------

Diffstat:

 Makefile                                  |  4 ++--
 arch/x86/kernel/cpu/mshyperv.c            |  6 +++++
 arch/x86/kernel/early-quirks.c            | 15 +++++-------
 drivers/acpi/button.c                     |  4 ++++
 drivers/char/ipmi/ipmi_bt_sm.c            |  2 +-
 drivers/pci/host/pcie-designware.c        |  8 +++----
 drivers/scsi/sd.c                         |  4 ++--
 drivers/staging/comedi/comedi_buf.c       | 37 ++++++++++++++++++++++++++--
 drivers/staging/comedi/comedi_fops.c      | 18 ++++++++++----
 drivers/staging/comedi/comedi_internal.h  |  2 ++
 drivers/staging/comedi/drivers/8255_pci.c | 34 ++++++++++++++++++++++++++
 drivers/tty/ipwireless/tty.c              |  3 ---
 drivers/tty/tty_buffer.c                  | 20 ++++------------
 drivers/tty/tty_io.c                      | 23 +++++++++++++-----
 drivers/usb/gadget/u_serial.c             |  4 ++--
 fs/btrfs/disk-io.c                        |  4 ++++
 fs/btrfs/extent-tree.c                    |  3 ++-
 fs/btrfs/transaction.c                    | 14 ++++-------
 fs/ext4/extents.c                         | 40 +++++++++++++++++++++++++++----
 fs/fs-writeback.c                         | 31 +++++++++++++++++-------
 fs/jffs2/compr_rtime.c                    |  4 ++--
 fs/jffs2/nodelist.h                       |  2 +-
 fs/jffs2/nodemgmt.c                       | 14 +++++++----
 fs/kernfs/dir.c                           |  2 +-
 fs/kernfs/inode.c                         | 14 +++++++----
 fs/posix_acl.c                            |  5 ++--
 fs/xfs/xfs_da_btree.c                     |  2 +-
 include/linux/backing-dev.h               |  2 +-
 include/linux/tty.h                       |  2 +-
 kernel/exit.c                             | 21 +++++++++-------
 kernel/pid_namespace.c                    |  4 +++-
 kernel/user_namespace.c                   | 11 ++++-----
 mm/backing-dev.c                          | 16 +++++++++----
 net/bluetooth/hci_event.c                 |  8 ++++++-
 security/integrity/ima/ima.h              |  2 +-
 security/integrity/ima/ima_fs.c           |  2 ++
 security/integrity/ima/ima_template_lib.c | 10 +++++---
 37 files changed, 280 insertions(+), 117 deletions(-)

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mikulas Patocka <[email protected]>

commit e79323bd87808fdfbc68ce6c5371bd224d9672ee upstream.

smp_read_barrier_depends() can be used if there is data dependency between the readers - i.e. if the read operation after the barrier uses address that was obtained from the read operation before the barrier.

In this file, there is only control dependency, no data dependecy, so the use of smp_read_barrier_depends() is incorrect. The code could fail in the following way:
* the cpu predicts that idx < entries is true and starts executing the body of the for loop
* the cpu fetches map->extent[0].first and map->extent[0].count
* the cpu fetches map->nr_extents
* the cpu verifies that idx < extents is true, so it commits the instructions in the body of the for loop

The problem is that in this scenario, the cpu read map->extent[0].first and map->nr_extents in the wrong order. We need a full read memory barrier to prevent it.

---
 kernel/user_namespace.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

@@ -152,7 +152,7 @@ static u32 map_id_range_down(struct uid_
 
 	/* Find the matching extent */
 	extents = map->nr_extents;
-	smp_read_barrier_depends();
+	smp_rmb();
 	for (idx = 0; idx < extents; idx++) {
 		first = map->extent[idx].first;
 		last = first + map->extent[idx].count - 1;

@@ -176,7 +176,7 @@ static u32 map_id_down(struct uid_gid_ma
 
 	/* Find the matching extent */
 	extents = map->nr_extents;
-	smp_read_barrier_depends();
+	smp_rmb();
 	for (idx = 0; idx < extents; idx++) {
 		first = map->extent[idx].first;
 		last = first + map->extent[idx].count - 1;

@@ -199,7 +199,7 @@ static u32 map_id_up(struct uid_gid_map
 
 	/* Find the matching extent */
 	extents = map->nr_extents;
-	smp_read_barrier_depends();
+	smp_rmb();
 	for (idx = 0; idx < extents; idx++) {
 		first = map->extent[idx].lower_first;
 		last = first + map->extent[idx].count - 1;

@@ -615,9 +615,8 @@ static ssize_t map_write(struct file *fi
 	 * were written before the count of the extents.
 	 *
 	 * To achieve this smp_wmb() is used on guarantee the write
-	 * order and smp_read_barrier_depends() is guaranteed that we
-	 * don't have crazy architectures returning stale data.
-	 *
+	 * order and smp_rmb() is guaranteed that we don't have crazy
+	 * architectures returning stale data.
 	 */
 	mutex_lock(&id_map_mutex);
 

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jiri Slaby <[email protected]>

commit a94cdd1f4d30f12904ab528152731fb13a812a16 upstream.

In read_all_bytes, we do

  unsigned char i;
  ...
  bt->read_data[0] = BMC2HOST;
  bt->read_count = bt->read_data[0];
  ...
  for (i = 1; i <= bt->read_count; i++)
    bt->read_data[i] = BMC2HOST;

If bt->read_data[0] == bt->read_count == 255, we loop infinitely in the 'for' loop. Make 'i' an 'int' instead of 'char' to get rid of the overflow and finish the loop after 255 iterations every time.

---
 drivers/char/ipmi/ipmi_bt_sm.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -352,7 +352,7 @@ static inline void write_all_bytes(struc
 
 static inline int read_all_bytes(struct si_sm_data *bt)
 {
-	unsigned char i;
+	unsigned int i;
 
 	/*
 	 * length is "framing info", minimum = 4: NetFn, Seq, Cmd, cCode.

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jason Wang <[email protected]>

commit ca3ba2a2f4a49a308e7d78c784d51b2332064f15 upstream.

This patch bypass the timer_irq_works() check for hyperv guest since:

- It was guaranteed to work.
- timer_irq_works() may fail sometime due to the lpj calibration were inaccurate in a hyperv guest or a buggy host.

In the future, we should get the tsc frequency from hypervisor and use preset lpj instead.

[ hpa: I would prefer to not defer things to "the future" in the future... ]

---
 arch/x86/kernel/cpu/mshyperv.c |    6 ++++++
 1 file changed, 6 insertions(+)

@@ -26,6 +26,7 @@
 #include <asm/irq_regs.h>
 #include <asm/i8259.h>
 #include <asm/apic.h>
+#include <asm/timer.h>
 
 struct ms_hyperv_info ms_hyperv;
 EXPORT_SYMBOL_GPL(ms_hyperv);

@@ -105,6 +106,11 @@ static void __init ms_hyperv_init_platfo
 
 	if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE)
 		clocksource_register_hz(&hyperv_cs, NSEC_PER_SEC/100);
+
+#ifdef CONFIG_X86_IO_APIC
+	no_timer_check = 1;
+#endif
+
 }
 
 const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = {

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Neil Horman <[email protected]>

commit 6f8a1b335fde143b7407036e2368d3cd6eb55674 upstream.

Commit 03bbcb2e7e2 (iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets) properly disables irq remapping on the 5500/5520 chipsets that don't correctly perform that feature.

However, when I wrote it, I followed the errata sheet linked in that commit too closely, and explicitly tied the activation of the quirk to revision 0x13 of the chip, under the assumption that earlier revisions were not in the field. Recently a system was reported to be suffering from this remap bug and the quirk hadn't triggered, because the revision id register read at a lower value that 0x13, so the quirk test failed improperly. Given this, it seems only prudent to adjust this quirk so that any revision less than 0x13 has the quirk asserted.

[ tglx: Removed the 0x12 comparison of pci id 3405 as this is covered

    	by the <= 0x13 check already ]

---
 arch/x86/kernel/early-quirks.c |   15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

@@ -203,18 +203,15 @@ static void __init intel_remapping_check
 	revision = read_pci_config_byte(num, slot, func, PCI_REVISION_ID);
 
 	/*
- 	 * Revision 13 of all triggering devices id in this quirk have
-	 * a problem draining interrupts when irq remapping is enabled,
-	 * and should be flagged as broken.  Additionally revisions 0x12
-	 * and 0x22 of device id 0x3405 has this problem.
+	 * Revision <= 13 of all triggering devices id in this quirk
+	 * have a problem draining interrupts when irq remapping is
+	 * enabled, and should be flagged as broken. Additionally
+	 * revision 0x22 of device id 0x3405 has this problem.
 	 */
-	if (revision == 0x13)
+	if (revision <= 0x13)
 		set_irq_remapping_broken();
-	else if ((device == 0x3405) &&
-	    ((revision == 0x12) ||
-	     (revision == 0x22)))
+	else if (device == 0x3405 && revision == 0x22)
 		set_irq_remapping_broken();
-
 }
 
 /*

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mohit Kumar <[email protected]>

commit dbffdd6862e67d60703f2df66c558bf448f81d6e upstream.

The Synopsys PCIe core provides one pair of 32-bit BARs (BAR 0 and BAR 1). The BARs can be configured as follows:

- One 64-bit BAR: BARs 0 and 1 are combined to form a single 64-bit BAR
- Two 32-bit BARs: BARs 0 and 1 are two independent 32-bit BARs

This patch corrects 64-bit, non-prefetchable memory BAR configuration implemented in dw driver.

---
 drivers/pci/host/pcie-designware.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -800,7 +800,7 @@ void dw_pcie_setup_rc(struct pcie_port *
 
 	/* setup RC BARs */
 	dw_pcie_writel_rc(pp, 0x00000004, PCI_BASE_ADDRESS_0);
-	dw_pcie_writel_rc(pp, 0x00000004, PCI_BASE_ADDRESS_1);
+	dw_pcie_writel_rc(pp, 0x00000000, PCI_BASE_ADDRESS_1);
 
 	/* setup interrupt pins */
 	dw_pcie_readl_rc(pp, PCI_INTERRUPT_LINE, &val);

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mohit Kumar <[email protected]>

commit 017fcdc30cdae18c0946eef1ece1f14b4c7897ba upstream.

This patch corrects iATU programming for cfg1, io and mem viewport. Enable ATU only after configuring it.

---
 drivers/pci/host/pcie-designware.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

@@ -522,13 +522,13 @@ static void dw_pcie_prog_viewport_cfg1(s
 	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1,
 			  PCIE_ATU_VIEWPORT);
 	dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_CFG1, PCIE_ATU_CR1);
-	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
 	dw_pcie_writel_rc(pp, pp->cfg1_base, PCIE_ATU_LOWER_BASE);
 	dw_pcie_writel_rc(pp, (pp->cfg1_base >> 32), PCIE_ATU_UPPER_BASE);
 	dw_pcie_writel_rc(pp, pp->cfg1_base + pp->config.cfg1_size - 1,
 			  PCIE_ATU_LIMIT);
 	dw_pcie_writel_rc(pp, busdev, PCIE_ATU_LOWER_TARGET);
 	dw_pcie_writel_rc(pp, 0, PCIE_ATU_UPPER_TARGET);
+	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
 }
 
 static void dw_pcie_prog_viewport_mem_outbound(struct pcie_port *pp)

@@ -537,7 +537,6 @@ static void dw_pcie_prog_viewport_mem_ou
 	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX0,
 			  PCIE_ATU_VIEWPORT);
 	dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_MEM, PCIE_ATU_CR1);
-	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
 	dw_pcie_writel_rc(pp, pp->mem_base, PCIE_ATU_LOWER_BASE);
 	dw_pcie_writel_rc(pp, (pp->mem_base >> 32), PCIE_ATU_UPPER_BASE);
 	dw_pcie_writel_rc(pp, pp->mem_base + pp->config.mem_size - 1,

@@ -545,6 +544,7 @@ static void dw_pcie_prog_viewport_mem_ou
 	dw_pcie_writel_rc(pp, pp->config.mem_bus_addr, PCIE_ATU_LOWER_TARGET);
 	dw_pcie_writel_rc(pp, upper_32_bits(pp->config.mem_bus_addr),
 			  PCIE_ATU_UPPER_TARGET);
+	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
 }
 
 static void dw_pcie_prog_viewport_io_outbound(struct pcie_port *pp)

@@ -553,7 +553,6 @@ static void dw_pcie_prog_viewport_io_out
 	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND | PCIE_ATU_REGION_INDEX1,
 			  PCIE_ATU_VIEWPORT);
 	dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_IO, PCIE_ATU_CR1);
-	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
 	dw_pcie_writel_rc(pp, pp->io_base, PCIE_ATU_LOWER_BASE);
 	dw_pcie_writel_rc(pp, (pp->io_base >> 32), PCIE_ATU_UPPER_BASE);
 	dw_pcie_writel_rc(pp, pp->io_base + pp->config.io_size - 1,

@@ -561,6 +560,7 @@ static void dw_pcie_prog_viewport_io_out
 	dw_pcie_writel_rc(pp, pp->config.io_bus_addr, PCIE_ATU_LOWER_TARGET);
 	dw_pcie_writel_rc(pp, upper_32_bits(pp->config.io_bus_addr),
 			  PCIE_ATU_UPPER_TARGET);
+	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
 }
 
 static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Lan Tianyu <[email protected]>

commit 0bf6368ee8f25826d0645c0f7a4f17c8845356a4 upstream.

Commit 1696d9d (ACPI: Remove the old /proc/acpi/event interface) removed ACPI Button event which originally was sent to userspace via /proc/acpi/event. This caused ACPI shutdown regression on gentoo in VirtualBox. Now ACPI events are sent to userspace via netlink, so add ACPI Button event back via netlink routine.

References: https://bugzilla.kernel.org/show_bug.cgi?id=71721

---
 drivers/acpi/button.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -302,6 +302,10 @@ static void acpi_button_notify(struct ac
 			input_sync(input);
 
 			pm_wakeup_event(&device->dev, 0);
+			acpi_bus_generate_netlink_event(
+					device->pnp.device_class,
+					dev_name(&device->dev),
+					event, ++button->pushed);
 		}
 		break;
 	default:

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ian Abbott <[email protected]>

commit 268d1e799663b795cba15c64f5d29407786a9dd4 upstream.

According to National Instruments' PCI-DIO-96/PXI-6508/PCI-6503 User Manual, the physical address in PCI BAR1 needs to be OR'ed with 0x80 and written to register offset 0xC0 in the "MITE" registers (BAR0). Do so during initialization of the National Instruments boards handled by the "8255_pci" driver. The boards were previously handled by the "ni_pcidio" driver, where the initialization was done by mite_setup() in the "mite" module. The "mite" module comes with too much extra baggage for the "8255_pci" driver to deal with so use a local, simpler initialization function.

---
 drivers/staging/comedi/drivers/8255_pci.c |   34 ++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

@@ -56,6 +56,7 @@ Configuration Options: not applicable, u
 #include "../comedidev.h"
 
 #include "8255.h"
+#include "mite.h"
 
 enum pci_8255_boardid {
 	BOARD_ADLINK_PCI7224,

@@ -79,6 +80,7 @@ struct pci_8255_boardinfo {
 	const char *name;
 	int dio_badr;
 	int n_8255;
+	unsigned int has_mite:1;
 };
 
 static const struct pci_8255_boardinfo pci_8255_boards[] = {

@@ -126,36 +128,43 @@ static const struct pci_8255_boardinfo p
 		.name		= "ni_pci-dio-96",
 		.dio_badr	= 1,
 		.n_8255		= 4,
+		.has_mite	= 1,
 	},
 	[BOARD_NI_PCIDIO96B] = {
 		.name		= "ni_pci-dio-96b",
 		.dio_badr	= 1,
 		.n_8255		= 4,
+		.has_mite	= 1,
 	},
 	[BOARD_NI_PXI6508] = {
 		.name		= "ni_pxi-6508",
 		.dio_badr	= 1,
 		.n_8255		= 4,
+		.has_mite	= 1,
 	},
 	[BOARD_NI_PCI6503] = {
 		.name		= "ni_pci-6503",
 		.dio_badr	= 1,
 		.n_8255		= 1,
+		.has_mite	= 1,
 	},
 	[BOARD_NI_PCI6503B] = {
 		.name		= "ni_pci-6503b",
 		.dio_badr	= 1,
 		.n_8255		= 1,
+		.has_mite	= 1,
 	},
 	[BOARD_NI_PCI6503X] = {
 		.name		= "ni_pci-6503x",
 		.dio_badr	= 1,
 		.n_8255		= 1,
+		.has_mite	= 1,
 	},
 	[BOARD_NI_PXI_6503] = {
 		.name		= "ni_pxi-6503",
 		.dio_badr	= 1,
 		.n_8255		= 1,
+		.has_mite	= 1,
 	},
 };
 

@@ -163,6 +172,25 @@ struct pci_8255_private {
 	void __iomem *mmio_base;
 };
 
+static int pci_8255_mite_init(struct pci_dev *pcidev)
+{
+	void __iomem *mite_base;
+	u32 main_phys_addr;
+
+	/* ioremap the MITE registers (BAR 0) temporarily */
+	mite_base = pci_ioremap_bar(pcidev, 0);
+	if (!mite_base)
+		return -ENOMEM;
+
+	/* set data window to main registers (BAR 1) */
+	main_phys_addr = pci_resource_start(pcidev, 1);
+	writel(main_phys_addr | WENAB, mite_base + MITE_IODWBSR);
+
+	/* finished with MITE registers */
+	iounmap(mite_base);
+	return 0;
+}
+
 static int pci_8255_mmio(int dir, int port, int data, unsigned long iobase)
 {
 	void __iomem *mmio_base = (void __iomem *)iobase;

@@ -201,6 +229,12 @@ static int pci_8255_auto_attach(struct c
 	if (ret)
 		return ret;
 
+	if (board->has_mite) {
+		ret = pci_8255_mite_init(pcidev);
+		if (ret)
+			return ret;
+	}
+
 	is_mmio = (pci_resource_flags(pcidev, board->dio_badr) &
 		   IORESOURCE_MEM) != 0;
 	if (is_mmio) {

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ian Abbott <[email protected]>

commit b34aa86f12e8848ba453215602c8c50fa63c4cb3 upstream.

Mmapping a comedi data buffer with lockdep checking enabled produced the following kernel debug messages:

======================================================
[ INFO: possible circular locking dependency detected ]
3.5.0-rc3-ija1+ #9 Tainted: G C
-------------------------------------------------------
comedi_test/4160 is trying to acquire lock:
(&dev->mutex#2){+.+.+.}, at: [<ffffffffa00313f4>] comedi_mmap+0x57/0x1d9 [comedi]

but task is already holding lock:
(&mm->mmap_sem){++++++}, at: [<ffffffff810c96fe>] vm_mmap_pgoff+0x41/0x76

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&mm->mmap_sem){++++++}:

       [<ffffffff8106d0e8>] lock_acquire+0x97/0x105
       [<ffffffff810ce3bc>] might_fault+0x6d/0x90
       [<ffffffffa0031ffb>] do_devinfo_ioctl.isra.7+0x11e/0x14c [comedi]
       [<ffffffffa003227f>] comedi_unlocked_ioctl+0x256/0xe48 [comedi]
       [<ffffffff810f7fcd>] vfs_ioctl+0x18/0x34
       [<ffffffff810f87fd>] do_vfs_ioctl+0x382/0x43c
       [<ffffffff810f88f9>] sys_ioctl+0x42/0x65
       [<ffffffff81415c62>] system_call_fastpath+0x16/0x1b

-> #0 (&dev->mutex#2){+.+.+.}:

       [<ffffffff8106c528>] __lock_acquire+0x101d/0x1591
       [<ffffffff8106d0e8>] lock_acquire+0x97/0x105
       [<ffffffff8140c894>] mutex_lock_nested+0x46/0x2a4
       [<ffffffffa00313f4>] comedi_mmap+0x57/0x1d9 [comedi]
       [<ffffffff810d5816>] mmap_region+0x281/0x492
       [<ffffffff810d5c92>] do_mmap_pgoff+0x26b/0x2a7
       [<ffffffff810c971a>] vm_mmap_pgoff+0x5d/0x76
       [<ffffffff810d493f>] sys_mmap_pgoff+0xc7/0x10d
       [<ffffffff81004d36>] sys_mmap+0x16/0x20
       [<ffffffff81415c62>] system_call_fastpath+0x16/0x1b

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_sem);
                               lock(&dev->mutex#2);
                               lock(&mm->mmap_sem);

lock(&dev->mutex#2);

*** DEADLOCK ***

To avoid the circular dependency, just try to get the lock in comedi_mmap() instead of blocking. Since the comedi device's main mutex is heavily used, do a down-read of its attach_lock rwsemaphore instead. Trying to down-read attach_lock should only fail if some task has down-write locked it, and that is only done while the comedi device is being attached to or detached from a low-level hardware device.

Unfortunately, acquiring the attach_lock doesn't prevent another task replacing the comedi data buffer we are trying to mmap. The details of the buffer are held in a struct comedi_buf_map and pointed to by s->async->buf_map where s is the comedi subdevice whose buffer we are trying to map. The struct comedi_buf_map is already reference counted with a struct kref, so we can stop it being freed prematurely.

Modify comedi_mmap() to call new function comedi_buf_map_from_subdev_get() to read the subdevice's current buffer map pointer and increment its reference instead of accessing async->buf_map directly. Call comedi_buf_map_put() to decrement the reference once the buffer map structure has been dealt with. (Note that comedi_buf_map_put() does nothing if passed a NULL pointer.)

comedi_buf_map_from_subdev_get() checks the subdevice's buffer map pointer has been set and the buffer map has been initialized enough for comedi_mmap() to deal with it (specifically, check the n_pages member has been set to a non-zero value). If all is well, the buffer map's reference is incremented and a pointer to it is returned. The comedi subdevice's spin-lock is used to protect the checks. Also use the spin-lock in __comedi_buf_alloc() and __comedi_buf_free() to protect changes to the subdevice's buffer map structure pointer and the buffer map structure's n_pages member. (This checking of n_pages is a bit clunky and I [Ian Abbott] plan to deal with it in the future.)

---
 drivers/staging/comedi/comedi_buf.c      |   37 +++++++++++++++++++++++++++++--
 drivers/staging/comedi/comedi_fops.c     |   18 +++++++++++----
 drivers/staging/comedi/comedi_internal.h |    2 +
 3 files changed, 51 insertions(+), 6 deletions(-)

@@ -61,6 +61,8 @@ static void __comedi_buf_free(struct com
 			      struct comedi_subdevice *s)
 {
 	struct comedi_async *async = s->async;
+	struct comedi_buf_map *bm;
+	unsigned long flags;
 
 	if (async->prealloc_buf) {
 		vunmap(async->prealloc_buf);

@@ -68,8 +70,11 @@ static void __comedi_buf_free(struct com
 		async->prealloc_bufsz = 0;
 	}
 
-	comedi_buf_map_put(async->buf_map);
+	spin_lock_irqsave(&s->spin_lock, flags);
+	bm = async->buf_map;
 	async->buf_map = NULL;
+	spin_unlock_irqrestore(&s->spin_lock, flags);
+	comedi_buf_map_put(bm);
 }
 
 static void __comedi_buf_alloc(struct comedi_device *dev,

@@ -80,6 +85,7 @@ static void __comedi_buf_alloc(struct co
 	struct page **pages = NULL;
 	struct comedi_buf_map *bm;
 	struct comedi_buf_page *buf;
+	unsigned long flags;
 	unsigned i;
 
 	if (!IS_ENABLED(CONFIG_HAS_DMA) && s->async_dma_dir != DMA_NONE) {

@@ -92,8 +98,10 @@ static void __comedi_buf_alloc(struct co
 	if (!bm)
 		return;
 
-	async->buf_map = bm;
 	kref_init(&bm->refcount);
+	spin_lock_irqsave(&s->spin_lock, flags);
+	async->buf_map = bm;
+	spin_unlock_irqrestore(&s->spin_lock, flags);
 	bm->dma_dir = s->async_dma_dir;
 	if (bm->dma_dir != DMA_NONE)
 		/* Need ref to hardware device to free buffer later. */

@@ -127,7 +135,9 @@ static void __comedi_buf_alloc(struct co
 
 		pages[i] = virt_to_page(buf->virt_addr);
 	}
+	spin_lock_irqsave(&s->spin_lock, flags);
 	bm->n_pages = i;
+	spin_unlock_irqrestore(&s->spin_lock, flags);
 
 	/* vmap the prealloc_buf if all the pages were allocated */
 	if (i == n_pages)

@@ -150,6 +160,29 @@ int comedi_buf_map_put(struct comedi_buf
 	return 1;
 }
 
+/* returns s->async->buf_map and increments its kref refcount */
+struct comedi_buf_map *
+comedi_buf_map_from_subdev_get(struct comedi_subdevice *s)
+{
+	struct comedi_async *async = s->async;
+	struct comedi_buf_map *bm = NULL;
+	unsigned long flags;
+
+	if (!async)
+		return NULL;
+
+	spin_lock_irqsave(&s->spin_lock, flags);
+	bm = async->buf_map;
+	/* only want it if buffer pages allocated */
+	if (bm && bm->n_pages)
+		comedi_buf_map_get(bm);
+	else
+		bm = NULL;
+	spin_unlock_irqrestore(&s->spin_lock, flags);
+
+	return bm;
+}
+
 bool comedi_buf_is_mmapped(struct comedi_async *async)
 {
 	struct comedi_buf_map *bm = async->buf_map;

@@ -1923,14 +1923,21 @@ static int comedi_mmap(struct file *file
 	struct comedi_device *dev = file->private_data;
 	struct comedi_subdevice *s;
 	struct comedi_async *async;
-	struct comedi_buf_map *bm;
+	struct comedi_buf_map *bm = NULL;
 	unsigned long start = vma->vm_start;
 	unsigned long size;
 	int n_pages;
 	int i;
 	int retval;
 
-	mutex_lock(&dev->mutex);
+	/*
+	 * 'trylock' avoids circular dependency with current->mm->mmap_sem
+	 * and down-reading &dev->attach_lock should normally succeed without
+	 * contention unless the device is in the process of being attached
+	 * or detached.
+	 */
+	if (!down_read_trylock(&dev->attach_lock))
+		return -EAGAIN;
 
 	if (!dev->attached) {
 		dev_dbg(dev->class_dev, "no driver attached\n");

@@ -1970,7 +1977,9 @@ static int comedi_mmap(struct file *file
 	}
 
 	n_pages = size >> PAGE_SHIFT;
-	bm = async->buf_map;
+
+	/* get reference to current buf map (if any) */
+	bm = comedi_buf_map_from_subdev_get(s);
 	if (!bm || n_pages > bm->n_pages) {
 		retval = -EINVAL;
 		goto done;

@@ -1994,7 +2003,8 @@ static int comedi_mmap(struct file *file
 
 	retval = 0;
 done:
-	mutex_unlock(&dev->mutex);
+	up_read(&dev->attach_lock);
+	comedi_buf_map_put(bm);	/* put reference to buf map - okay if NULL */
 	return retval;
 }
 

@@ -19,6 +19,8 @@ void comedi_buf_reset(struct comedi_asyn
 bool comedi_buf_is_mmapped(struct comedi_async *async);
 void comedi_buf_map_get(struct comedi_buf_map *bm);
 int comedi_buf_map_put(struct comedi_buf_map *bm);
+struct comedi_buf_map *comedi_buf_map_from_subdev_get(
+		struct comedi_subdevice *s);
 unsigned int comedi_buf_write_n_allocated(struct comedi_async *async);
 void comedi_device_cancel_all(struct comedi_device *dev);
 

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Richard Cochran <[email protected]>

commit 88391d49abb7d8dee91d405f96bd9e003cb6798d upstream.

The hash values 0 and 1 are reserved for magic directory entries, but the code only prevents names hashing to 0. This patch fixes the test to also prevent hash value 1.

---
 fs/kernfs/dir.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -37,7 +37,7 @@ static unsigned int kernfs_name_hash(con
 	hash = (end_name_hash(hash) ^ hash_ptr((void *)ns, 31));
 	hash &= 0x7fffffffU;
 	/* Reserve hash numbers 0, 1 and INT_MAX for magic directory entries */
-	if (hash < 1)
+	if (hash < 2)
 		hash += 2;
 	if (hash >= INT_MAX)
 		hash = INT_MAX - 1;

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tejun Heo <[email protected]>

commit 4afddd60a770560d370d6f85c5aef57c16bf7502 upstream.

kernfs_iattrs is allocated lazily when operations which require it take place; unfortunately, the lazy allocation and returning weren't properly synchronized and when there are multiple concurrent operations, it might end up returning kernfs_iattrs which hasn't finished initialization yet or different copies to different callers.

Fix it by synchronizing with a mutex. This can be smarter with memory barriers but let's go there if it actually turns out to be necessary.

---
 fs/kernfs/inode.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

@@ -48,14 +48,18 @@ void __init kernfs_inode_init(void)
 
 static struct kernfs_iattrs *kernfs_iattrs(struct kernfs_node *kn)
 {
+	static DEFINE_MUTEX(iattr_mutex);
+	struct kernfs_iattrs *ret;
 	struct iattr *iattrs;
 
+	mutex_lock(&iattr_mutex);
+
 	if (kn->iattr)
-		return kn->iattr;
+		goto out_unlock;
 
 	kn->iattr = kzalloc(sizeof(struct kernfs_iattrs), GFP_KERNEL);
 	if (!kn->iattr)
-		return NULL;
+		goto out_unlock;
 	iattrs = &kn->iattr->ia_iattr;
 
 	/* assign default attributes */

@@ -65,8 +69,10 @@ static struct kernfs_iattrs *kernfs_iatt
 	iattrs->ia_atime = iattrs->ia_mtime = iattrs->ia_ctime = CURRENT_TIME;
 
 	simple_xattrs_init(&kn->iattr->xattrs);
-
-	return kn->iattr;
+out_unlock:
+	ret = kn->iattr;
+	mutex_unlock(&iattr_mutex);
+	return ret;
 }
 
 static int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr)

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Hannes Reinecke <[email protected]>

commit 723abd87f6e536f1353c8f64f621520bc29523a3 upstream.

The 'active' sysfs attribute should refer to the currently active tty devices the console is running on, not the currently active console. The console structure doesn't refer to any device in sysfs, only the tty the console is running on has. So we need to print out the tty names in 'active', not the console names.

There is one special-case, which is tty0. If the console is directed to it, we want 'tty0' to show up in the file, so user-space knows that the messages get forwarded to the active VT. The ->device() callback would resolve tty0, though. Hence, treat it special and don't call into the VT layer to resolve it (plymouth is known to depend on it).

---
 drivers/tty/tty_io.c |   23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

@@ -1271,12 +1271,13 @@ static void pty_line_name(struct tty_dri
  *
  *	Locking: None
  */
-static void tty_line_name(struct tty_driver *driver, int index, char *p)
+static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p)
 {
 	if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE)
-		strcpy(p, driver->name);
+		return sprintf(p, "%s", driver->name);
 	else
-		sprintf(p, "%s%d", driver->name, index + driver->name_base);
+		return sprintf(p, "%s%d", driver->name,
+			       index + driver->name_base);
 }
 
 /**

@@ -3545,9 +3546,19 @@ static ssize_t show_cons_active(struct d
 		if (i >= ARRAY_SIZE(cs))
 			break;
 	}
-	while (i--)
-		count += sprintf(buf + count, "%s%d%c",
-				 cs[i]->name, cs[i]->index, i ? ' ':'\n');
+	while (i--) {
+		int index = cs[i]->index;
+		struct tty_driver *drv = cs[i]->device(cs[i], &index);
+
+		/* don't resolve tty0 as some programs depend on it */
+		if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR))
+			count += tty_line_name(drv, index, buf + count);
+		else
+			count += sprintf(buf + count, "%s%d",
+					 cs[i]->name, cs[i]->index);
+
+		count += sprintf(buf + count, "%c", i ? ' ':'\n');
+	}
 	console_unlock();
 
 	return count;

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Peter Hurley <[email protected]>

commit a9c3f68f3cd8d55f809fbdb0c138ed061ea1bd25 upstream.

The user-settable knob, low_latency, has been the source of several BUG reports which stem from flush_to_ldisc() running in interrupt context. Since 3.12, which added several sleeping locks (termios_rwsem and buf->lock) to the input processing path, the frequency of these BUG reports has increased.

Note that changes in 3.12 did not introduce this regression; sleeping locks were first added to the input processing path with the removal of the BKL from N_TTY in commit a88a69c91256418c5907c2f1f8a0ec0a36f9e6cc,
'n_tty: Fix loss of echoed characters and remove bkl from n_tty' and later in commit 38db89799bdf11625a831c5af33938dcb11908b6, 'tty: throttling race fix'. Since those changes, executing flush_to_ldisc() in interrupt_context (ie, low_latency set), is unsafe.

However, since most devices do not validate if the low_latency setting is appropriate for the context (process or interrupt) in which they receive data, some reports are due to misconfiguration. Further, serial dma devices for which dma fails, resort to interrupt receiving as a backup without resetting low_latency.

Historically, low_latency was used to force wake-up the reading process rather than wait for the next scheduler tick. The effect was to trim multiple milliseconds of latency from when the process would receive new data.

Recent tests [1] have shown that the reading process now receives data with only 10's of microseconds latency without low_latency set.

Remove the low_latency rx steering from tty_flip_buffer_push(); however, leave the knob as an optional hint to drivers that can tune their rx fifos and such like. Cleanup stale code comments regarding low_latency.

[1] https://lkml.org/lkml/2014/2/20/434

"Yay.. thats an annoying historical pain in the butt gone."
-- Alan Cox

---
 drivers/tty/ipwireless/tty.c  |    3 ---
 drivers/tty/tty_buffer.c      |   20 ++++----------------
 drivers/usb/gadget/u_serial.c |    4 ++--
 include/linux/tty.h           |    2 +-
 4 files changed, 7 insertions(+), 22 deletions(-)

@@ -176,9 +176,6 @@ void ipwireless_tty_received(struct ipw_
 				": %d chars not inserted to flip buffer!\n",
 				length - work);
 
-	/*
-	 * This may sleep if ->low_latency is set
-	 */
 	if (work)
 		tty_flip_buffer_push(&tty->port);
 }

@@ -351,14 +351,11 @@ EXPORT_SYMBOL(tty_insert_flip_string_fla
  *	Takes any pending buffers and transfers their ownership to the
  *	ldisc side of the queue. It then schedules those characters for
  *	processing by the line discipline.
- *	Note that this function can only be used when the low_latency flag
- *	is unset. Otherwise the workqueue won't be flushed.
  */
 
 void tty_schedule_flip(struct tty_port *port)
 {
 	struct tty_bufhead *buf = &port->buf;
-	WARN_ON(port->low_latency);
 
 	buf->tail->commit = buf->tail->used;
 	schedule_work(&buf->work);

@@ -482,17 +479,15 @@ static void flush_to_ldisc(struct work_s
  */
 void tty_flush_to_ldisc(struct tty_struct *tty)
 {
-	if (!tty->port->low_latency)
-		flush_work(&tty->port->buf.work);
+	flush_work(&tty->port->buf.work);
 }
 
 /**
  *	tty_flip_buffer_push	-	terminal
  *	@port: tty port to push
  *
- *	Queue a push of the terminal flip buffers to the line discipline. This
- *	function must not be called from IRQ context if port->low_latency is
- *	set.
+ *	Queue a push of the terminal flip buffers to the line discipline.
+ *	Can be called from IRQ/atomic context.
  *
  *	In the event of the queue being busy for flipping the work will be
  *	held off and retried later.

@@ -500,14 +495,7 @@ void tty_flush_to_ldisc(struct tty_struc
 
 void tty_flip_buffer_push(struct tty_port *port)
 {
-	struct tty_bufhead *buf = &port->buf;
-
-	buf->tail->commit = buf->tail->used;
-
-	if (port->low_latency)
-		flush_to_ldisc(&buf->work);
-	else
-		schedule_work(&buf->work);
+	tty_schedule_flip(port);
 }
 EXPORT_SYMBOL(tty_flip_buffer_push);
 

@@ -549,8 +549,8 @@ static void gs_rx_push(unsigned long _po
 		port->read_started--;
 	}
 
-	/* Push from tty to ldisc; without low_latency set this is handled by
-	 * a workqueue, so we won't get callbacks and can hold port_lock
+	/* Push from tty to ldisc; this is handled by a workqueue,
+	 * so we won't get callbacks and can hold port_lock
 	 */
 	if (do_push)
 		tty_flip_buffer_push(&port->port);

@@ -208,7 +208,7 @@ struct tty_port {
 	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
 	unsigned long		flags;		/* TTY flags ASY_*/
 	unsigned char		console:1,	/* port is a console */
-				low_latency:1;	/* direct buffer flush */
+				low_latency:1;	/* optional: tune for latency */
 	struct mutex		mutex;		/* Locking */
 	struct mutex		buf_mutex;	/* Buffer alloc lock */
 	unsigned char		*xmit_buf;	/* Optional buffer */

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Alan Stern <[email protected]>

commit 7aae51347b21eb738dc1981df1365b57a6c5ee4e upstream.

Evidently some wacky USB-ATA bridges don't recognize the SYNCHRONIZE CACHE command, as shown in this email thread:

	http://marc.info/?t=138978356200002&r=1&w=2

The fact that we can't tell them to drain their caches shouldn't prevent the system from going into suspend. Therefore sd_sync_cache() shouldn't return an error if the device replies with an Invalid Command ASC.

---
 drivers/scsi/sd.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -1463,8 +1463,8 @@ static int sd_sync_cache(struct scsi_dis
 			sd_print_sense_hdr(sdkp, &sshdr);
 		/* we need to evaluate the error return  */
 		if (scsi_sense_valid(&sshdr) &&
-			/* 0x3a is medium not present */
-			sshdr.asc == 0x3a)
+			(sshdr.asc == 0x3a ||	/* medium not present */
+			 sshdr.asc == 0x20))	/* invalid command */
 				/* this is no error here */
 				return 0;
 

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Claudio Takahasi <[email protected]>

commit 5981a8821b774ada0be512fd9bad7c241e17657e upstream.

This patch fixes authentication failure on LE link re-connection when BlueZ acts as slave (peripheral). LTK is removed from the internal list after its first use causing PIN or Key missing reply when re-connecting the link. The LE Long Term Key Request event indicates that the master is attempting to encrypt or re-encrypt the link.

Pre-condition: BlueZ host paired and running as slave. How to reproduce(master):

1) Establish an ACL LE encrypted link
2) Disconnect the link
3) Try to re-establish the ACL LE encrypted link (fails)

      LE Connection Complete (0x01)
        Status: Success (0x00)
        Handle: 64
        Role: Slave (0x01)

...
@ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000

      LE Long Term Key Request (0x05)
        Handle: 64
        Random number: 875be18439d9aa37
        Encryption diversifier: 0x76ed
< HCI Command: LE Long Term Key Request Reply (0x08|0x001a) plen 18
        Handle: 64
        Long term key: 2aa531db2fce9f00a0569c7d23d17409

      LE Long Term Key Request Reply (0x08|0x001a) ncmd 1
        Status: Success (0x00)
        Handle: 64

        Status: Success (0x00)
        Handle: 64
        Encryption: Enabled with AES-CCM (0x01)
...
@ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 3
< HCI Command: LE Set Advertise Enable (0x08|0x000a) plen 1
        Advertising: Enabled (0x01)

      LE Set Advertise Enable (0x08|0x000a) ncmd 1
        Status: Success (0x00)

      LE Connection Complete (0x01)
        Status: Success (0x00)
        Handle: 64
        Role: Slave (0x01)

...
@ Device Connected: 00:02:72:DC:29:C9 (1) flags 0x0000

      LE Long Term Key Request (0x05)
        Handle: 64
        Random number: 875be18439d9aa37
        Encryption diversifier: 0x76ed
< HCI Command: LE Long Term Key Request Neg Reply (0x08|0x001b) plen 2
        Handle: 64

      LE Long Term Key Request Neg Reply (0x08|0x001b) ncmd 1
        Status: Success (0x00)
        Handle: 64

        Status: Success (0x00)
        Handle: 64
        Reason: Authentication Failure (0x05)

@ Device Disconnected: 00:02:72:DC:29:C9 (1) reason 0

---
 net/bluetooth/hci_event.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

@@ -3593,7 +3593,13 @@ static void hci_le_ltk_request_evt(struc
 
 	hci_send_cmd(hdev, HCI_OP_LE_LTK_REPLY, sizeof(cp), &cp);
 
-	if (ltk->type & HCI_SMP_STK) {
+	/* Ref. Bluetooth Core SPEC pages 1975 and 2004. STK is a
+	 * temporary key used to encrypt a connection following
+	 * pairing. It is used during the Encrypted Session Setup to
+	 * distribute the keys. Later, security can be re-established
+	 * using a distributed LTK.
+	 */
+	if (ltk->type == HCI_SMP_STK_SLAVE) {
 		list_del(&ltk->list);
 		kfree(ltk);
 	}

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Roberto Sassu <[email protected]>

commit c019e307ad82a8ee652b8ccbacf69ae94263b07b upstream.

With the new template mechanism introduced in IMA since kernel 3.13, the format of data sent through the binary_runtime_measurements interface is slightly changed. Now, for a generic measurement, the format of template data (after the template name) is:

template_len | field1_len | field1 | ... | fieldN_len | fieldN

In addition, fields containing a string now include the '\0' termination character.

Instead, the format for the 'ima' template should be:

SHA1 digest | event name length | event name

It must be noted that while in the IMA 3.13 code 'event name length' is 'IMA_EVENT_NAME_LEN_MAX + 1' (256 bytes), so that the template digest is calculated correctly, and 'event name' contains '\0', in the pre 3.13 code 'event name length' is exactly the string length and 'event name' does not contain the termination character.

The patch restores the behavior of the IMA code pre 3.13 for the 'ima' template so that legacy userspace tools obtain a consistent behavior when receiving data from the binary_runtime_measurements interface regardless of which kernel version is used.

---
 security/integrity/ima/ima.h              |    2 +-
 security/integrity/ima/ima_fs.c           |    2 ++
 security/integrity/ima/ima_template_lib.c |   10 +++++++---
 3 files changed, 10 insertions(+), 4 deletions(-)

@@ -27,7 +27,7 @@
 #include "../integrity.h"
 
 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
-		     IMA_SHOW_ASCII };
+		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
 
 /* digest size for IMA, fits SHA1 or MD5 */

@@ -160,6 +160,8 @@ static int ima_measurements_show(struct
 
 		if (is_ima_template && strcmp(field->field_id, "d") == 0)
 			show = IMA_SHOW_BINARY_NO_FIELD_LEN;
+		if (is_ima_template && strcmp(field->field_id, "n") == 0)
+			show = IMA_SHOW_BINARY_OLD_STRING_FMT;
 		field->field_show(m, show, &e->template_data[i]);
 	}
 	return 0;

@@ -109,13 +109,16 @@ static void ima_show_template_data_binar
 					  enum data_formats datafmt,
 					  struct ima_field_data *field_data)
 {
+	u32 len = (show == IMA_SHOW_BINARY_OLD_STRING_FMT) ?
+	    strlen(field_data->data) : field_data->len;
+
 	if (show != IMA_SHOW_BINARY_NO_FIELD_LEN)
-		ima_putc(m, &field_data->len, sizeof(u32));
+		ima_putc(m, &len, sizeof(len));
 
-	if (!field_data->len)
+	if (!len)
 		return;
 
-	ima_putc(m, field_data->data, field_data->len);
+	ima_putc(m, field_data->data, len);
 }
 
 static void ima_show_template_field_data(struct seq_file *m,

@@ -129,6 +132,7 @@ static void ima_show_template_field_data
 		break;
 	case IMA_SHOW_BINARY:
 	case IMA_SHOW_BINARY_NO_FIELD_LEN:
+	case IMA_SHOW_BINARY_OLD_STRING_FMT:
 		ima_show_template_data_binary(m, show, datafmt, field_data);
 		break;
 	default:

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Derek Basehore <[email protected]>

commit 6ca738d60c563d5c6cf6253ee4b8e76fa77b2b9e upstream.

bdi_wakeup_thread_delayed() used the mod_delayed_work() function to schedule work to writeback dirty inodes. The problem with this is that it can delay work that is scheduled for immediate execution, such as the work from sync_inodes_sb(). This can happen since mod_delayed_work() can now steal work from a work_queue. This fixes the problem by using queue_delayed_work() instead. This is a regression caused by commit 839a8e8660b6 ("writeback: replace custom worker pool implementation with unbound workqueue").

The reason that this causes a problem is that laptop-mode will change the delay, dirty_writeback_centisecs, to 60000 (10 minutes) by default. In the case that bdi_wakeup_thread_delayed() races with sync_inodes_sb(), sync will be stopped for 10 minutes and trigger a hung task. Even if dirty_writeback_centisecs is not long enough to cause a hung task, we still don't want to delay sync for that long.

We fix the problem by using queue_delayed_work() when we want to schedule writeback sometime in future. This function doesn't change the timer if it is already armed.

For the same reason, we also change bdi_writeback_workfn() to immediately queue the work again in the case that the work_list is not empty. The same problem can happen if the sync work is run on the rescue worker.

---
 fs/fs-writeback.c |    8 ++++----
 mm/backing-dev.c  |    5 ++++-
 2 files changed, 8 insertions(+), 5 deletions(-)

@@ -1039,10 +1039,10 @@ void bdi_writeback_workfn(struct work_st
 		trace_writeback_pages_written(pages_written);
 	}
 
-	if (!list_empty(&bdi->work_list) ||
-	    (wb_has_dirty_io(wb) && dirty_writeback_interval))
-		queue_delayed_work(bdi_wq, &wb->dwork,
-			msecs_to_jiffies(dirty_writeback_interval * 10));
+	if (!list_empty(&bdi->work_list))
+		mod_delayed_work(bdi_wq, &wb->dwork, 0);
+	else if (wb_has_dirty_io(wb) && dirty_writeback_interval)
+		bdi_wakeup_thread_delayed(bdi);
 
 	current->flags &= ~PF_SWAPWRITE;
 }

@@ -288,13 +288,16 @@ int bdi_has_dirty_io(struct backing_dev_
  * Note, we wouldn't bother setting up the timer, but this function is on the
  * fast-path (used by '__mark_inode_dirty()'), so we save few context switches
  * by delaying the wake-up.
+ *
+ * We have to be careful not to postpone flush work if it is scheduled for
+ * earlier. Thus we use queue_delayed_work().
  */
 void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi)
 {
 	unsigned long timeout;
 
 	timeout = msecs_to_jiffies(dirty_writeback_interval * 10);
-	mod_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+	queue_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
 }
 
 /*

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jan Kara <[email protected]>

commit 5acda9d12dcf1ad0d9a5a2a7c646de3472fa7555 upstream.

After commit 839a8e8660b6 ("writeback: replace custom worker pool implementation with unbound workqueue") when device is removed while we are writing to it we crash in bdi_writeback_workfn() -> set_worker_desc() because bdi->dev is NULL.

This can happen because even though bdi_unregister() cancels all pending flushing work, nothing really prevents new ones from being queued from balance_dirty_pages() or other places.

Fix the problem by clearing BDI_registered bit in bdi_unregister() and checking it before scheduling of any flushing work.

---
 fs/fs-writeback.c           |   23 ++++++++++++++++++-----
 include/linux/backing-dev.h |    2 +-
 mm/backing-dev.c            |   13 +++++++++----
 3 files changed, 28 insertions(+), 10 deletions(-)

@@ -89,16 +89,29 @@ static inline struct inode *wb_inode(str
 #define CREATE_TRACE_POINTS
 #include <trace/events/writeback.h>
 
+static void bdi_wakeup_thread(struct backing_dev_info *bdi)
+{
+	spin_lock_bh(&bdi->wb_lock);
+	if (test_bit(BDI_registered, &bdi->state))
+		mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+	spin_unlock_bh(&bdi->wb_lock);
+}
+
 static void bdi_queue_work(struct backing_dev_info *bdi,
 			   struct wb_writeback_work *work)
 {
 	trace_writeback_queue(bdi, work);
 
 	spin_lock_bh(&bdi->wb_lock);
+	if (!test_bit(BDI_registered, &bdi->state)) {
+		if (work->done)
+			complete(work->done);
+		goto out_unlock;
+	}
 	list_add_tail(&work->list, &bdi->work_list);
-	spin_unlock_bh(&bdi->wb_lock);
-
 	mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+out_unlock:
+	spin_unlock_bh(&bdi->wb_lock);
 }
 
 static void

@@ -114,7 +127,7 @@ __bdi_start_writeback(struct backing_dev
 	work = kzalloc(sizeof(*work), GFP_ATOMIC);
 	if (!work) {
 		trace_writeback_nowork(bdi);
-		mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+		bdi_wakeup_thread(bdi);
 		return;
 	}
 

@@ -161,7 +174,7 @@ void bdi_start_background_writeback(stru
 	 * writeback as soon as there is no other work to do.
 	 */
 	trace_writeback_wake_background(bdi);
-	mod_delayed_work(bdi_wq, &bdi->wb.dwork, 0);
+	bdi_wakeup_thread(bdi);
 }
 
 /*

@@ -1017,7 +1030,7 @@ void bdi_writeback_workfn(struct work_st
 	current->flags |= PF_SWAPWRITE;
 
 	if (likely(!current_is_workqueue_rescuer() ||
-		   list_empty(&bdi->bdi_list))) {
+		   !test_bit(BDI_registered, &bdi->state))) {
 		/*
 		 * The normal path.  Keep writing back @bdi until its
 		 * work_list is empty.  Note that this path is also taken

@@ -95,7 +95,7 @@ struct backing_dev_info {
 	unsigned int max_ratio, max_prop_frac;
 
 	struct bdi_writeback wb;  /* default writeback info for this bdi */
-	spinlock_t wb_lock;	  /* protects work_list */
+	spinlock_t wb_lock;	  /* protects work_list & wb.dwork scheduling */
 
 	struct list_head work_list;
 

@@ -297,7 +297,10 @@ void bdi_wakeup_thread_delayed(struct ba
 	unsigned long timeout;
 
 	timeout = msecs_to_jiffies(dirty_writeback_interval * 10);
-	queue_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+	spin_lock_bh(&bdi->wb_lock);
+	if (test_bit(BDI_registered, &bdi->state))
+		queue_delayed_work(bdi_wq, &bdi->wb.dwork, timeout);
+	spin_unlock_bh(&bdi->wb_lock);
 }
 
 /*

@@ -310,9 +313,6 @@ static void bdi_remove_from_list(struct
 	spin_unlock_bh(&bdi_lock);
 
 	synchronize_rcu_expedited();
-
-	/* bdi_list is now unused, clear it to mark @bdi dying */
-	INIT_LIST_HEAD(&bdi->bdi_list);
 }
 
 int bdi_register(struct backing_dev_info *bdi, struct device *parent,

@@ -363,6 +363,11 @@ static void bdi_wb_shutdown(struct backi
 	 */
 	bdi_remove_from_list(bdi);
 
+	/* Make sure nobody queues further work */
+	spin_lock_bh(&bdi->wb_lock);
+	clear_bit(BDI_registered, &bdi->state);
+	spin_unlock_bh(&bdi->wb_lock);
+
 	/*
 	 * Drain work list and shutdown the delayed_work.  At this point,
 	 * @bdi->bdi_list is empty telling bdi_Writeback_workfn() that @bdi

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mark Tinguely <[email protected]>

commit c88547a8119e3b581318ab65e9b72f27f23e641d upstream.

Commit f5ea1100 ("xfs: add CRCs to dir2/da node blocks") introduced in 3.10 incorrectly converted the btree hash index array pointer in xfs_da3_fixhashpath(). It resulted in the the current hash always being compared against the first entry in the btree rather than the current block index into the btree block's hash entry array. As a result, it was comparing the wrong hashes, and so could misorder the entries in the btree.

For most cases, this doesn't cause any problems as it requires hash collisions to expose the ordering problem. However, when there are hash collisions within a directory there is a very good probability that the entries will be ordered incorrectly and that actually matters when duplicate hashes are placed into or removed from the btree block hash entry array.

This bug results in an on-disk directory corruption and that results in directory verifier functions throwing corruption warnings into the logs. While no data or directory entries are lost, access to them may be compromised, and attempts to remove entries from a directory that has suffered from this corruption may result in a filesystem shutdown. xfs_repair will fix the directory hash ordering without data loss occuring.

[dchinner: wrote useful a commit message]

---
 fs/xfs/xfs_da_btree.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -1295,7 +1295,7 @@ xfs_da3_fixhashpath(
 		node = blk->bp->b_addr;
 		dp->d_ops->node_hdr_from_disk(&nodehdr, node);
 		btree = dp->d_ops->node_tree_p(node);
-		if (be32_to_cpu(btree->hashval) == lasthash)
+		if (be32_to_cpu(btree[blk->index].hashval) == lasthash)
 			break;
 		blk->hashval = lasthash;
 		btree[blk->index].hashval = cpu_to_be32(lasthash);

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Hidetoshi Seto <[email protected]>

commit f88ba6a2a44ee98e8d59654463dc157bb6d13c43 upstream.

I got an error on v3.13:
BTRFS error (device sdf1) in write_all_supers:3378: errno=-5 IO failure (errors while submitting device barriers.)

how to reproduce:

The reason of the error is that barrier_all_devices() failed to submit barrier to the missing device. However it is clear that we cannot do anything on missing device, and also it is not necessary to care chunks on the missing device.

This patch stops sending/waiting barrier if device is missing.

---
 fs/btrfs/disk-io.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -3244,6 +3244,8 @@ static int barrier_all_devices(struct bt
 	/* send down all the barriers */
 	head = &info->fs_devices->devices;
 	list_for_each_entry_rcu(dev, head, dev_list) {
+		if (dev->missing)
+			continue;
 		if (!dev->bdev) {
 			errors_send++;
 			continue;

@@ -3258,6 +3260,8 @@ static int barrier_all_devices(struct bt
 
 	/* wait for all the barriers */
 	list_for_each_entry_rcu(dev, head, dev_list) {
+		if (dev->missing)
+			continue;
 		if (!dev->bdev) {
 			errors_wait++;
 			continue;

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Josef Bacik <[email protected]>

commit 3bbb24b20a8800158c33eca8564f432dd14d0bf3 upstream.

Zach found this deadlock that would happen like this

btrfs_end_transaction <- reduce trans->use_count to 0
btrfs_run_delayed_refs

    btrfs_cow_block
      find_free_extent
	btrfs_start_transaction <- increase trans->use_count to 1
          allocate chunk
	btrfs_end_transaction <- decrease trans->use_count to 0
	  btrfs_run_delayed_refs
	    lock tree block we are cowing above ^^

We need to only decrease trans->use_count if it is above 1, otherwise leave it alone. This will make nested trans be the only ones who decrease their added ref, and will let us get rid of the trans->use_count++ hack if we have to commit the transaction. Thanks,

---
 fs/btrfs/transaction.c |   14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

@@ -683,7 +683,8 @@ static int __btrfs_end_transaction(struc
 	int lock = (trans->type != TRANS_JOIN_NOLOCK);
 	int err = 0;
 
-	if (--trans->use_count) {
+	if (trans->use_count > 1) {
+		trans->use_count--;
 		trans->block_rsv = trans->orig_rsv;
 		return 0;
 	}

@@ -731,17 +732,10 @@ static int __btrfs_end_transaction(struc
 	}
 
 	if (lock && ACCESS_ONCE(cur_trans->state) == TRANS_STATE_BLOCKED) {
-		if (throttle) {
-			/*
-			 * We may race with somebody else here so end up having
-			 * to call end_transaction on ourselves again, so inc
-			 * our use_count.
-			 */
-			trans->use_count++;
+		if (throttle)
 			return btrfs_commit_transaction(trans, root);
-		} else {
+		else
 			wake_up_process(info->transaction_kthread);
-		}
 	}
 
 	if (trans->type & __TRANS_FREEZABLE)

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Josef Bacik <[email protected]>

commit 573a075567f0174551e2fad2a3164afd2af788f2 upstream.

We could have possibly added an extent_op to the locked_ref while we dropped locked_ref->lock, so check for this case as well and loop around. Otherwise we could lose flag updates which would lead to extent tree corruption. Thanks,

---
 fs/btrfs/extent-tree.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

@@ -2444,7 +2444,8 @@ static noinline int __btrfs_run_delayed_
 			spin_unlock(&locked_ref->lock);
 			spin_lock(&delayed_refs->lock);
 			spin_lock(&locked_ref->lock);
-			if (rb_first(&locked_ref->ref_root)) {
+			if (rb_first(&locked_ref->ref_root) ||
+			    locked_ref->extent_op) {
 				spin_unlock(&locked_ref->lock);
 				spin_unlock(&delayed_refs->lock);
 				continue;

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Eric Whitney <[email protected]>

commit ce37c42919608e96ade3748fe23c3062a0a966c5 upstream.

Commit 3779473246 breaks the return of error codes from ext4_ext_handle_uninitialized_extents() in ext4_ext_map_blocks(). A portion of the patch assigns that function's signed integer return value to an unsigned int. Consequently, negatively valued error codes are lost and can be treated as a bogus allocated block count.

---
 fs/ext4/extents.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

@@ -4128,7 +4128,7 @@ int ext4_ext_map_blocks(handle_t *handle
 	struct ext4_extent newex, *ex, *ex2;
 	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	ext4_fsblk_t newblock = 0;
-	int free_on_err = 0, err = 0, depth;
+	int free_on_err = 0, err = 0, depth, ret;
 	unsigned int allocated = 0, offset = 0;
 	unsigned int allocated_clusters = 0;
 	struct ext4_allocation_request ar;

@@ -4189,9 +4189,13 @@ int ext4_ext_map_blocks(handle_t *handle
 			if (!ext4_ext_is_uninitialized(ex))
 				goto out;
 
-			allocated = ext4_ext_handle_uninitialized_extents(
+			ret = ext4_ext_handle_uninitialized_extents(
 				handle, inode, map, path, flags,
 				allocated, newblock);
+			if (ret < 0)
+				err = ret;
+			else
+				allocated = ret;
 			goto out3;
 		}
 	}

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Eric Whitney <[email protected]>

commit c06344939422bbd032ac967223a7863de57496b5 upstream.

Commit 9cb00419fa, which enables hole punching for bigalloc file systems, exposed a bug introduced by commit 6ae06ff51e in an earlier release. When run on a bigalloc file system, xfstests generic/013, 068, 075, 083, 091, 100, 112, 127, 263, 269, and 270 fail with e2fsck errors or cause kernel error messages indicating that previously freed blocks are being freed again.

The latter commit optimizes the selection of the starting extent in ext4_ext_rm_leaf() when hole punching by beginning with the extent supplied in the path argument rather than with the last extent in the leaf node (as is still done when truncating). However, the code in rm_leaf that initially sets partial_cluster to track cluster sharing on extent boundaries is only guaranteed to run if rm_leaf starts with the last node in the leaf. Consequently, partial_cluster is not correctly initialized when hole punching, and a cluster on the boundary of a punched region that should be retained may instead be deallocated.

---
 fs/ext4/extents.c |   21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

@@ -2585,6 +2585,27 @@ ext4_ext_rm_leaf(handle_t *handle, struc
 	ex_ee_block = le32_to_cpu(ex->ee_block);
 	ex_ee_len = ext4_ext_get_actual_len(ex);
 
+	/*
+	 * If we're starting with an extent other than the last one in the
+	 * node, we need to see if it shares a cluster with the extent to
+	 * the right (towards the end of the file). If its leftmost cluster
+	 * is this extent's rightmost cluster and it is not cluster aligned,
+	 * we'll mark it as a partial that is not to be deallocated.
+	 */
+
+	if (ex != EXT_LAST_EXTENT(eh)) {
+		ext4_fsblk_t current_pblk, right_pblk;
+		long long current_cluster, right_cluster;
+
+		current_pblk = ext4_ext_pblock(ex) + ex_ee_len - 1;
+		current_cluster = (long long)EXT4_B2C(sbi, current_pblk);
+		right_pblk = ext4_ext_pblock(ex + 1);
+		right_cluster = (long long)EXT4_B2C(sbi, right_pblk);
+		if (current_cluster == right_cluster &&
+			EXT4_PBLK_COFF(sbi, right_pblk))
+			*partial_cluster = -right_cluster;
+	}
+
 	trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster);
 
 	while (ex >= EXT_FIRST_EXTENT(eh) &&

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Eric Whitney <[email protected]>

commit ad6599ab3ac98a4474544086e048ce86ec15a4d1 upstream.

Xfstests generic/311 and shared/298 fail when run on a bigalloc file system. Kernel error messages produced during the tests report that blocks to be freed are already on the to-be-freed list. When e2fsck is run at the end of the tests, it typically reports bad i_blocks and bad free blocks counts.

The bug that causes these failures is located in ext4_ext_rm_leaf(). Code at the end of the function frees a partial cluster if it's not shared with an extent remaining in the leaf. However, if all the extents in the leaf have been removed, the code dereferences an invalid extent pointer (off the front of the leaf) when the check for sharing is made. This generally has the effect of unconditionally freeing the partial cluster, which leads to the observed failures when the partial cluster is shared with the last extent in the next leaf.

Fix this by attempting to free the cluster only if extents remain in the leaf. Any remaining partial cluster will be freed if possible when the next leaf is processed or when leaf removal is complete.

---
 fs/ext4/extents.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

@@ -2731,10 +2731,15 @@ ext4_ext_rm_leaf(handle_t *handle, struc
 		err = ext4_ext_correct_indexes(handle, inode, path);
 
 	/*
-	 * Free the partial cluster only if the current extent does not
-	 * reference it. Otherwise we might free used cluster.
+	 * If there's a partial cluster and at least one extent remains in
+	 * the leaf, free the partial cluster if it isn't shared with the
+	 * current extent.  If there's a partial cluster and no extents
+	 * remain in the leaf, it can't be freed here.  It can only be
+	 * freed when it's possible to determine if it's not shared with
+	 * any other extent - when the next leaf is processed or when space
+	 * removal is complete.
 	 */
-	if (*partial_cluster > 0 &&
+	if (*partial_cluster > 0 && eh->eh_entries &&
 	    (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) !=
 	     *partial_cluster)) {
 		int flags = get_default_free_blocks_flags(inode);

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <[email protected]>

commit 47ba9734403770a4c5e685b01f0a72b835dd4fff upstream.

This patch moves the dereference of "buffer" after the check for NULL. The only place which passes a NULL parameter is gfs2_set_acl().

---
 fs/posix_acl.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

@@ -723,7 +723,7 @@ posix_acl_to_xattr(struct user_namespace
 		   void *buffer, size_t size)
 {
 	posix_acl_xattr_header *ext_acl = (posix_acl_xattr_header *)buffer;
-	posix_acl_xattr_entry *ext_entry = ext_acl->a_entries;
+	posix_acl_xattr_entry *ext_entry;
 	int real_size, n;
 
 	real_size = posix_acl_xattr_size(acl->a_count);

@@ -731,7 +731,8 @@ posix_acl_to_xattr(struct user_namespace
 		return real_size;
 	if (real_size > size)
 		return -ERANGE;
-	
+
+	ext_entry = ext_acl->a_entries;
 	ext_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
 
 	for (n=0; n < acl->a_count; n++, ext_entry++) {

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Kamlakant Patel <[email protected]>

commit 3367da5610c50e6b83f86d366d72b41b350b06a2 upstream.

Creating a large file on a JFFS2 partition sometimes crashes with this call trace:

[  306.476000] CPU 13 Unable to handle kernel paging request at virtual address c0000000dfff8002, epc == ffffffffc03a80a8, ra == ffffffffc03a8044
[  306.488000] Oops[#1]:
[  306.488000] Cpu 13
[  306.492000] $ 0   : 0000000000000000 0000000000000000 0000000000008008 0000000000008007
[  306.500000] $ 4   : c0000000dfff8002 000000000000009f c0000000e0007cde c0000000ee95fa58
[  306.508000] $ 8   : 0000000000000001 0000000000008008 0000000000010000 ffffffffffff8002
[  306.516000] $12   : 0000000000007fa9 000000000000ff0e 000000000000ff0f 80e55930aebb92bb
[  306.524000] $16   : c0000000e0000000 c0000000ee95fa5c c0000000efc80000 ffffffffc09edd70
[  306.532000] $20   : ffffffffc2b60000 c0000000ee95fa58 0000000000000000 c0000000efc80000
[  306.540000] $24   : 0000000000000000 0000000000000004
[  306.548000] $28   : c0000000ee950000 c0000000ee95f738 0000000000000000 ffffffffc03a8044
[  306.556000] Hi    : 00000000000574a5
[  306.560000] Lo    : 6193b7a7e903d8c9
[  306.564000] epc   : ffffffffc03a80a8 jffs2_rtime_compress+0x98/0x198
[  306.568000]     Tainted: G        W
[  306.572000] ra    : ffffffffc03a8044 jffs2_rtime_compress+0x34/0x198
[  306.580000] Status: 5000f8e3    KX SX UX KERNEL EXL IE
[  306.584000] Cause : 00800008
[  306.588000] BadVA : c0000000dfff8002
[  306.592000] PrId  : 000c1100 (Netlogic XLP)
[  306.596000] Modules linked in:
[  306.596000] Process dd (pid: 170, threadinfo=c0000000ee950000, task=c0000000ee6e0858, tls=0000000000c47490)
[  306.608000] Stack : 7c547f377ddc7ee4 7ffc7f967f5d7fae 7f617f507fc37ff4 7e7d7f817f487f5f
        7d8e7fec7ee87eb3 7e977ff27eec7f9e 7d677ec67f917f67 7f3d7e457f017ed7
        7fd37f517f867eb2 7fed7fd17ca57e1d 7e5f7fe87f257f77 7fd77f0d7ede7fdb
        7fba7fef7e197f99 7fde7fe07ee37eb5 7f5c7f8c7fc67f65 7f457fb87f847e93
        7f737f3e7d137cd9 7f8e7e9c7fc47d25 7dbb7fac7fb67e52 7ff17f627da97f64
        7f6b7df77ffa7ec5 80057ef17f357fb3 7f767fa27dfc7fd5 7fe37e8e7fd07e53
        7e227fcf7efb7fa1 7f547e787fa87fcc 7fcb7fc57f5a7ffb 7fc07f6c7ea97e80
        7e2d7ed17e587ee0 7fb17f9d7feb7f31 7f607e797e887faa 7f757fdd7c607ff3
        7e877e657ef37fbd 7ec17fd67fe67ff7 7ff67f797ff87dc4 7eef7f3a7c337fa6
        7fe57fc97ed87f4b 7ebe7f097f0b8003 7fe97e2a7d997cba 7f587f987f3c7fa9
        ...
[  306.676000] Call Trace:
[  306.680000] [<ffffffffc03a80a8>] jffs2_rtime_compress+0x98/0x198
[  306.684000] [<ffffffffc0394f10>] jffs2_selected_compress+0x110/0x230
[  306.692000] [<ffffffffc039508c>] jffs2_compress+0x5c/0x388
[  306.696000] [<ffffffffc039dc58>] jffs2_write_inode_range+0xd8/0x388
[  306.704000] [<ffffffffc03971bc>] jffs2_write_end+0x16c/0x2d0
[  306.708000] [<ffffffffc01d3d90>] generic_file_buffered_write+0xf8/0x2b8
[  306.716000] [<ffffffffc01d4e7c>] __generic_file_aio_write+0x1ac/0x350
[  306.720000] [<ffffffffc01d50a0>] generic_file_aio_write+0x80/0x168
[  306.728000] [<ffffffffc021f7dc>] do_sync_write+0x94/0xf8
[  306.732000] [<ffffffffc021ff6c>] vfs_write+0xa4/0x1a0
[  306.736000] [<ffffffffc02202e8>] SyS_write+0x50/0x90
[  306.744000] [<ffffffffc0116cc0>] handle_sys+0x180/0x1a0
[  306.748000]
[  306.748000]
Code: 020b202d  0205282d  90a50000 <90840000> 14a40038  00000000  0060602d  0000282d  016c5823
[  306.760000] ---[ end trace 79dd088435be02d0 ]---

Segmentation fault

This crash is caused because the 'positions' is declared as an array of signed short. The value of position is in the range 0..65535, and will be converted to a negative number when the position is greater than 32767 and causes a corruption and crash. Changing the definition to 'unsigned short' fixes this issue

---
 fs/jffs2/compr_rtime.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -33,7 +33,7 @@ static int jffs2_rtime_compress(unsigned
 				unsigned char *cpage_out,
 				uint32_t *sourcelen, uint32_t *dstlen)
 {
-	short positions[256];
+	unsigned short positions[256];
 	int outpos = 0;
 	int pos=0;
 

@@ -74,7 +74,7 @@ static int jffs2_rtime_decompress(unsign
 				  unsigned char *cpage_out,
 				  uint32_t srclen, uint32_t destlen)
 {
-	short positions[256];
+	unsigned short positions[256];
 	int outpos = 0;
 	int pos=0;
 

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ajesh Kunhipurayil Vijayan <[email protected]>

commit 41bf1a24c1001f4d0d41a78e1ac575d2f14789d7 upstream.

mounting JFFS2 partition sometimes crashes with this call trace:

[ 1322.240000] Kernel bug detected[#1]:
[ 1322.244000] Cpu 2
[ 1322.244000] $ 0   : 0000000000000000 0000000000000018 000000003ff00070 0000000000000001
[ 1322.252000] $ 4   : 0000000000000000 c0000000f3980150 0000000000000000 0000000000010000
[ 1322.260000] $ 8   : ffffffffc09cd5f8 0000000000000001 0000000000000088 c0000000ed300de8
[ 1322.268000] $12   : e5e19d9c5f613a45 ffffffffc046d464 0000000000000000 66227ba5ea67b74e
[ 1322.276000] $16   : c0000000f1769c00 c0000000ed1e0200 c0000000f3980150 0000000000000000
[ 1322.284000] $20   : c0000000f3a80000 00000000fffffffc c0000000ed2cfbd8 c0000000f39818f0
[ 1322.292000] $24   : 0000000000000004 0000000000000000
[ 1322.300000] $28   : c0000000ed2c0000 c0000000ed2cfab8 0000000000010000 ffffffffc039c0b0
[ 1322.308000] Hi    : 000000000000023c
[ 1322.312000] Lo    : 000000000003f802
[ 1322.316000] epc   : ffffffffc039a9f8 check_tn_node+0x88/0x3b0
[ 1322.320000]     Not tainted
[ 1322.324000] ra    : ffffffffc039c0b0 jffs2_do_read_inode_internal+0x1250/0x1e48
[ 1322.332000] Status: 5400f8e3    KX SX UX KERNEL EXL IE
[ 1322.336000] Cause : 00800034
[ 1322.340000] PrId  : 000c1004 (Netlogic XLP)
[ 1322.344000] Modules linked in:
[ 1322.348000] Process jffs2_gcd_mtd7 (pid: 264, threadinfo=c0000000ed2c0000, task=c0000000f0e68dd8, tls=0000000000000000)
[ 1322.356000] Stack : c0000000f1769e30 c0000000ed010780 c0000000ed010780 c0000000ed300000
        c0000000f1769c00 c0000000f3980150 c0000000f3a80000 00000000fffffffc
        c0000000ed2cfbd8 ffffffffc039c0b0 ffffffffc09c6340 0000000000001000
        0000000000000dec ffffffffc016c9d8 c0000000f39805a0 c0000000f3980180
        0000008600000000 0000000000000000 0000000000000000 0000000000000000
        0001000000000dec c0000000f1769d98 c0000000ed2cfb18 0000000000010000
        0000000000010000 0000000000000044 c0000000f3a80000 c0000000f1769c00
        c0000000f3d207a8 c0000000f1769d98 c0000000f1769de0 ffffffffc076f9c0
        0000000000000009 0000000000000000 0000000000000000 ffffffffc039cf90
        0000000000000017 ffffffffc013fbdc 0000000000000001 000000010003e61c
        ...
[ 1322.424000] Call Trace:
[ 1322.428000] [<ffffffffc039a9f8>] check_tn_node+0x88/0x3b0
[ 1322.432000] [<ffffffffc039c0b0>] jffs2_do_read_inode_internal+0x1250/0x1e48
[ 1322.440000] [<ffffffffc039cf90>] jffs2_do_crccheck_inode+0x70/0xd0
[ 1322.448000] [<ffffffffc03a1b80>] jffs2_garbage_collect_pass+0x160/0x870
[ 1322.452000] [<ffffffffc03a392c>] jffs2_garbage_collect_thread+0xdc/0x1f0
[ 1322.460000] [<ffffffffc01541c8>] kthread+0xb8/0xc0
[ 1322.464000] [<ffffffffc0106d18>] kernel_thread_helper+0x10/0x18
[ 1322.472000]
[ 1322.472000]
Code: 67bd0050  94a4002c  2c830001 <00038036> de050218  2403fffc  0080a82d  00431824  24630044
[ 1322.480000] ---[ end trace b052bb90e97dfbf5 ]---

The variable csize in structure jffs2_tmp_dnode_info is of type uint16_t, but it is used to hold the compressed data length(csize) which is declared as uint32_t. So, when the value of csize exceeds 16bits, it gets truncated when assigned to tn->csize. This is causing a kernel BUG.
Changing the definition of csize in jffs2_tmp_dnode_info to uint32_t fixes the issue.

---
 fs/jffs2/nodelist.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -231,7 +231,7 @@ struct jffs2_tmp_dnode_info
 	uint32_t version;
 	uint32_t data_crc;
 	uint32_t partial_crc;
-	uint16_t csize;
+	uint32_t csize;
 	uint16_t overlapped;
 };
 

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Li Zefan <[email protected]>

commit 13b546d96207c131eeae15dc7b26c6e7d0f1cad7 upstream.

We triggered soft-lockup under stress test on 2.6.34 kernel.

BUG: soft lockup - CPU#1 stuck for 60009ms! [lockf2.test:14488]

...
[<bf09a4d4>] (jffs2_do_reserve_space+0x420/0x440 [jffs2]) [<bf09a528>] (jffs2_reserve_space_gc+0x34/0x78 [jffs2]) [<bf0a1350>] (jffs2_garbage_collect_dnode.isra.3+0x264/0x478 [jffs2]) [<bf0a2078>] (jffs2_garbage_collect_pass+0x9c0/0xe4c [jffs2]) [<bf09a670>] (jffs2_reserve_space+0x104/0x2a8 [jffs2]) [<bf09dc48>] (jffs2_write_inode_range+0x5c/0x4d4 [jffs2]) [<bf097d8c>] (jffs2_write_end+0x198/0x2c0 [jffs2]) [<c00e00a4>] (generic_file_buffered_write+0x158/0x200) [<c00e14f4>] (__generic_file_aio_write+0x3a4/0x414) [<c00e15c0>] (generic_file_aio_write+0x5c/0xbc) [<c012334c>] (do_sync_write+0x98/0xd4)
[<c0123a84>] (vfs_write+0xa8/0x150)
[<c0123d74>] (sys_write+0x3c/0xc0)]

Fix this by adding a cond_resched() in the while loop.

---
 fs/jffs2/nodemgmt.c |   13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

@@ -211,20 +211,25 @@ out:
 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
 			   uint32_t *len, uint32_t sumsize)
 {
-	int ret = -EAGAIN;
+	int ret;
 	minsize = PAD(minsize);
 
 	jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize);
 
-	spin_lock(&c->erase_completion_lock);
-	while(ret == -EAGAIN) {
+	while (true) {
+		spin_lock(&c->erase_completion_lock);
 		ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
 		if (ret) {
 			jffs2_dbg(1, "%s(): looping, ret is %d\n",
 				  __func__, ret);
 		}
+		spin_unlock(&c->erase_completion_lock);
+
+		if (ret == -EAGAIN)
+			cond_resched();
+		else
+			break;
 	}
-	spin_unlock(&c->erase_completion_lock);
 	if (!ret)
 		ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
 

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Li Zefan <[email protected]>

commit 3ead9578443b66ddb3d50ed4f53af8a0c0298ec5 upstream.

@wait is a local variable, so if we don't remove it from the wait queue list, later wake_up() may end up accessing invalid memory.

This was spotted by eyes.

---
 fs/jffs2/nodemgmt.c |    1 +
 1 file changed, 1 insertion(+)

@@ -179,6 +179,7 @@ int jffs2_reserve_space(struct jffs2_sb_
 					spin_unlock(&c->erase_completion_lock);
 
 					schedule();
+					remove_wait_queue(&c->erase_wait, &wait);
 				} else
 					spin_unlock(&c->erase_completion_lock);
 			} else if (ret)

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Oleg Nesterov <[email protected]>

commit dfccbb5e49a621c1b21a62527d61fc4305617aca upstream.

wait_task_zombie() first does EXIT_ZOMBIE->EXIT_DEAD transition and drops tasklist_lock. If this task is not the natural child and it is traced, we change its state back to EXIT_ZOMBIE for ->real_parent.

The last transition is racy, this is even documented in 50b8d257486a "ptrace: partially fix the do_wait(WEXITED) vs EXIT_DEAD->EXIT_ZOMBIE race". wait_consider_task() tries to detect this transition and clear ->notask_error but we can't rely on ptrace_reparented(), debugger can exit and do ptrace_unlink() before its sub-thread sets EXIT_ZOMBIE.

And there is another problem which were missed before: this transition can also race with reparent_leader() which doesn't reset >exit_signal if EXIT_DEAD, assuming that this task must be reaped by someone else. So the tracee can be re-parented with ->exit_signal != SIGCHLD, and if /sbin/init doesn't use __WALL it becomes unreapable.

Change reparent_leader() to update ->exit_signal even if EXIT_DEAD.
Note: this is the simple temporary hack for -stable, it doesn't try to solve all problems, it will be reverted by the next changes.

---
 kernel/exit.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

@@ -560,9 +560,6 @@ static void reparent_leader(struct task_
 				struct list_head *dead)
 {
 	list_move_tail(&p->sibling, &p->real_parent->children);
-
-	if (p->exit_state == EXIT_DEAD)
-		return;
 	/*
 	 * If this is a threaded reparent there is no need to
 	 * notify anyone anything has happened.

@@ -570,9 +567,19 @@ static void reparent_leader(struct task_
 	if (same_thread_group(p->real_parent, father))
 		return;
 
-	/* We don't want people slaying init.  */
+	/*
+	 * We don't want people slaying init.
+	 *
+	 * Note: we do this even if it is EXIT_DEAD, wait_task_zombie()
+	 * can change ->exit_state to EXIT_ZOMBIE. If this is the final
+	 * state, do_notify_parent() was already called and ->exit_signal
+	 * doesn't matter.
+	 */
 	p->exit_signal = SIGCHLD;
 
+	if (p->exit_state == EXIT_DEAD)
+		return;
+
 	/* If it has exited notify the new parent about this child's death. */
 	if (!p->ptrace &&
 	    p->exit_state == EXIT_ZOMBIE && thread_group_empty(p)) {

3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Oleg Nesterov <[email protected]>

commit c39df5fa37b0623589508c95515b4aa1531c524e upstream.

Commit 8aac62706ada ("move exit_task_namespaces() outside of exit_notify()") breaks pppd and the exiting service crashes the kernel:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
    IP: ppp_register_channel+0x13/0x20 [ppp_generic]
    Call Trace:
      ppp_asynctty_open+0x12b/0x170 [ppp_async]
      tty_ldisc_open.isra.2+0x27/0x60
      tty_ldisc_hangup+0x1e3/0x220
      __tty_hangup+0x2c4/0x440
      disassociate_ctty+0x61/0x270
      do_exit+0x7f2/0xa50

ppp_register_channel() needs ->net_ns and current->nsproxy == NULL.

Move disassociate_ctty() before exit_task_namespaces(), it doesn't make sense to delay it after perf_event_exit_task() or cgroup_exit().

This also allows to use task_work_add() inside the (nontrivial) code paths in disassociate_ctty().

Investigated by Peter Hurley.

---
 kernel/exit.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

@@ -791,6 +791,8 @@ void do_exit(long code)
 	exit_shm(tsk);
 	exit_files(tsk);
 	exit_fs(tsk);
+	if (group_dead)
+		disassociate_ctty(1);
 	exit_task_namespaces(tsk);
 	exit_task_work(tsk);
 	check_stack_usage();

@@ -806,13 +808,9 @@ void do_exit(long code)
 
 	cgroup_exit(tsk, 1);
 
-	if (group_dead)
-		disassociate_ctty(1);
-
 	module_put(task_thread_info(tsk)->exec_domain->module);
 
 	proc_exit_connector(tsk);
-
 	/*
 	 * FIXME: do that only when needed, using sched_exit tracepoint
 	 */

Build results:

	total: 126 pass: 121 skipped: 4 fail: 1

Qemu tests all passed. Results are expected.
For reference, the failing build is powerpc:allmodconfig, which is failing upstream as well.

Details are available at http://server.roeck-us.net:8010/builders.

Note that the series has 34 patches for me, not 33.

Guenter

Same here, I removed one a few days ago, did you miss that?

greg k-h

Compiled and booted. No dmesg regressions.

-- Shuah

Shuah Khan
Senior Linux Kernel Developer - Open Source Group
Samsung Research America(Silicon Valley)
[email protected] | (970) 672-0658

Thanks for testing and letting me know.

greg k-h