[PATCH 3.14 00/29] 3.14.76-stable review

[PATCH 3.14 00/29] 3.14.76-stable review

[Greg Kroah-Hartman]

This is the start of the stable review cycle for the 3.14.76 release.
There are 29 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 Tue Aug 16 20:07:18 UTC 2016.
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.x/stable-review/patch-3.14.76-rc1.gz
or in the git tree and branch at:
  git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-3.14.y
and the diffstat can be found below.

thanks,

greg k-h

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

Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Linux 3.14.76-rc1

Vegard Nossum <vegard.nossum@oracle.com>
    ext4: fix reference counting bug on block allocation error

Eric Dumazet <edumazet@google.com>
    tcp: make challenge acks less predictable

Soheil Hassas Yeganeh <soheil@google.com>
    tcp: consider recv buf for the initial window scale

Vegard Nossum <vegard.nossum@oracle.com>
    net/irda: fix NULL pointer dereference on memory allocation failure

Beniamino Galvani <bgalvani@redhat.com>
    bonding: set carrier off for devices created through netlink

Vegard Nossum <vegard.nossum@oracle.com>
    ext4: short-cut orphan cleanup on error

Vegard Nossum <vegard.nossum@oracle.com>
    ext4: don't call ext4_should_journal_data() on the journal inode

Jan Kara <jack@suse.cz>
    ext4: fix deadlock during page writeback

Vegard Nossum <vegard.nossum@oracle.com>
    ext4: check for extents that wrap around

Herbert Xu <herbert@gondor.apana.org.au>
    crypto: scatterwalk - Fix test in scatterwalk_done

Herbert Xu <herbert@gondor.apana.org.au>
    crypto: gcm - Filter out async ghash if necessary

Wei Fang <fangwei1@huawei.com>
    fuse: fix wrong assignment of ->flags in fuse_send_init()

Fabian Frederick <fabf@skynet.be>
    sysv, ipc: fix security-layer leaking

Vegard Nossum <vegard.nossum@oracle.com>
    block: fix use-after-free in seq file

Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
    IB/security: Restrict use of the write() interface

James Bottomley <James.Bottomley@HansenPartnership.com>
    scsi_lib: correctly retry failed zero length REQ_TYPE_FS commands

Christoph Hellwig <hch@lst.de>
    scsi: remove scsi_end_request

Theodore Ts'o <tytso@mit.edu>
    random: strengthen input validation for RNDADDTOENTCNT

John Johansen <john.johansen@canonical.com>
    apparmor: fix ref count leak when profile sha1 hash is read

David Howells <dhowells@redhat.com>
    KEYS: 64-bit MIPS needs to use compat_sys_keyctl for 32-bit userspace

Dave Weinstein <olorin@google.com>
    arm: oabi compat: add missing access checks

Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    USB: fix up incorrect quirk

Bjørn Mork <bjorn@mork.no>
    cdc_ncm: do not call usbnet_link_change from cdc_ncm_bind

Andy Lutomirski <luto@kernel.org>
    x86/mm: Improve switch_mm() barrier comments

Karl Heiss <kheiss@gmail.com>
    sctp: Prevent soft lockup when sctp_accept() is called during a timeout event

Andy Lutomirski <luto@kernel.org>
    x86/mm: Add barriers and document switch_mm()-vs-flush synchronization

Tejun Heo <tj@kernel.org>
    printk: do cond_resched() between lines while outputting to consoles

Hugh Dickins <hughd@google.com>
    mm: migrate dirty page without clear_page_dirty_for_io etc

Alan Stern <stern@rowland.harvard.edu>
    USB: fix invalid memory access in hub_activate()


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

Diffstat:

 Makefile                                     |   4 +-
 arch/arm/kernel/sys_oabi-compat.c            |   8 +-
 arch/mips/kernel/scall64-n32.S               |   2 +-
 arch/mips/kernel/scall64-o32.S               |   2 +-
 arch/x86/include/asm/mmu_context.h           |  33 +++++++-
 arch/x86/mm/tlb.c                            |  25 +++++-
 block/genhd.c                                |   1 +
 crypto/gcm.c                                 |   4 +-
 crypto/scatterwalk.c                         |   3 +-
 drivers/char/random.c                        |  13 +--
 drivers/infiniband/core/ucm.c                |   4 +
 drivers/infiniband/core/ucma.c               |   3 +
 drivers/infiniband/core/uverbs_main.c        |   5 ++
 drivers/infiniband/hw/ipath/ipath_file_ops.c |   5 ++
 drivers/infiniband/hw/qib/qib_file_ops.c     |   5 ++
 drivers/net/bonding/bond_netlink.c           |   6 +-
 drivers/net/usb/cdc_ncm.c                    |  20 ++---
 drivers/scsi/scsi_lib.c                      | 116 ++++++++-------------------
 drivers/usb/core/hub.c                       |  23 +++++-
 drivers/usb/core/quirks.c                    |   8 +-
 fs/ext4/extents.c                            |   8 +-
 fs/ext4/inode.c                              |  35 ++++++--
 fs/ext4/mballoc.c                            |  17 +---
 fs/ext4/super.c                              |  10 +++
 fs/fuse/inode.c                              |   2 +-
 include/linux/console.h                      |   1 +
 include/rdma/ib.h                            |  16 ++++
 ipc/msg.c                                    |   2 +-
 ipc/sem.c                                    |  12 +--
 kernel/panic.c                               |   3 +
 kernel/printk/printk.c                       |  35 +++++++-
 mm/migrate.c                                 |  51 +++++++-----
 net/ipv4/tcp_input.c                         |  12 ++-
 net/ipv4/tcp_output.c                        |   3 +-
 net/irda/af_irda.c                           |   7 +-
 net/sctp/sm_sideeffect.c                     |  42 +++++-----
 security/apparmor/apparmorfs.c               |   1 +
 37 files changed, 349 insertions(+), 198 deletions(-)

[PATCH 3.14 01/29] USB: fix invalid memory access in hub_activate()

[Greg Kroah-Hartman]

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

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

From: Alan Stern <stern@rowland.harvard.edu>

commit e50293ef9775c5f1cf3fcc093037dd6a8c5684ea upstream.

Commit 8520f38099cc ("USB: change hub initialization sleeps to
delayed_work") changed the hub_activate() routine to make part of it
run in a workqueue.  However, the commit failed to take a reference to
the usb_hub structure or to lock the hub interface while doing so.  As
a result, if a hub is plugged in and quickly unplugged before the work
routine can run, the routine will try to access memory that has been
deallocated.  Or, if the hub is unplugged while the routine is
running, the memory may be deallocated while it is in active use.

This patch fixes the problem by taking a reference to the usb_hub at
the start of hub_activate() and releasing it at the end (when the work
is finished), and by locking the hub interface while the work routine
is running.  It also adds a check at the start of the routine to see
if the hub has already been disconnected, in which nothing should be
done.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Alexandru Cornea <alexandru.cornea@intel.com>
Tested-by: Alexandru Cornea <alexandru.cornea@intel.com>
Fixes: 8520f38099cc ("USB: change hub initialization sleeps to delayed_work")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ luis: backported to 3.16:
  - Added forward declaration of hub_release() which mainline had with commit
    32a6958998c5 ("usb: hub: convert khubd into workqueue") ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Signed-off-by: Charles (Chas) Williams <ciwillia@brocade.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/core/hub.c |   23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -106,6 +106,7 @@ EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rws
 #define HUB_DEBOUNCE_STEP	  25
 #define HUB_DEBOUNCE_STABLE	 100
 
+static void hub_release(struct kref *kref);
 static int usb_reset_and_verify_device(struct usb_device *udev);
 
 static inline char *portspeed(struct usb_hub *hub, int portstatus)
@@ -1023,10 +1024,20 @@ static void hub_activate(struct usb_hub
 	unsigned delay;
 
 	/* Continue a partial initialization */
-	if (type == HUB_INIT2)
-		goto init2;
-	if (type == HUB_INIT3)
+	if (type == HUB_INIT2 || type == HUB_INIT3) {
+		device_lock(hub->intfdev);
+
+		/* Was the hub disconnected while we were waiting? */
+		if (hub->disconnected) {
+			device_unlock(hub->intfdev);
+			kref_put(&hub->kref, hub_release);
+			return;
+		}
+		if (type == HUB_INIT2)
+			goto init2;
 		goto init3;
+	}
+	kref_get(&hub->kref);
 
 	/* The superspeed hub except for root hub has to use Hub Depth
 	 * value as an offset into the route string to locate the bits
@@ -1220,6 +1231,7 @@ static void hub_activate(struct usb_hub
 			PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
 			schedule_delayed_work(&hub->init_work,
 					msecs_to_jiffies(delay));
+			device_unlock(hub->intfdev);
 			return;		/* Continues at init3: below */
 		} else {
 			msleep(delay);
@@ -1240,6 +1252,11 @@ static void hub_activate(struct usb_hub
 	/* Allow autosuspend if it was suppressed */
 	if (type <= HUB_INIT3)
 		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
+
+	if (type == HUB_INIT2 || type == HUB_INIT3)
+		device_unlock(hub->intfdev);
+
+	kref_put(&hub->kref, hub_release);
 }
 
 /* Implement the continuations for the delays above */

[PATCH 3.14 02/29] mm: migrate dirty page without clear_page_dirty_for_io etc

[Greg Kroah-Hartman]

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

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

From: Hugh Dickins <hughd@google.com>

commit 42cb14b110a5698ccf26ce59c4441722605a3743 upstream.

clear_page_dirty_for_io() has accumulated writeback and memcg subtleties
since v2.6.16 first introduced page migration; and the set_page_dirty()
which completed its migration of PageDirty, later had to be moderated to
__set_page_dirty_nobuffers(); then PageSwapBacked had to skip that too.

No actual problems seen with this procedure recently, but if you look into
what the clear_page_dirty_for_io(page)+set_page_dirty(newpage) is actually
achieving, it turns out to be nothing more than moving the PageDirty flag,
and its NR_FILE_DIRTY stat from one zone to another.

It would be good to avoid a pile of irrelevant decrementations and
incrementations, and improper event counting, and unnecessary descent of
the radix_tree under tree_lock (to set the PAGECACHE_TAG_DIRTY which
radix_tree_replace_slot() left in place anyway).

Do the NR_FILE_DIRTY movement, like the other stats movements, while
interrupts still disabled in migrate_page_move_mapping(); and don't even
bother if the zone is the same.  Do the PageDirty movement there under
tree_lock too, where old page is frozen and newpage not yet visible:
bearing in mind that as soon as newpage becomes visible in radix_tree, an
un-page-locked set_page_dirty() might interfere (or perhaps that's just
not possible: anything doing so should already hold an additional
reference to the old page, preventing its migration; but play safe).

But we do still need to transfer PageDirty in migrate_page_copy(), for
those who don't go the mapping route through migrate_page_move_mapping().

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ciwillia@brocade.com: backported to 3.14: adjusted context]
Signed-off-by: Charles (Chas) Williams <ciwillia@brocade.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 mm/migrate.c |   51 +++++++++++++++++++++++++++++++--------------------
 1 file changed, 31 insertions(+), 20 deletions(-)

--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -30,6 +30,7 @@
 #include <linux/mempolicy.h>
 #include <linux/vmalloc.h>
 #include <linux/security.h>
+#include <linux/backing-dev.h>
 #include <linux/memcontrol.h>
 #include <linux/syscalls.h>
 #include <linux/hugetlb.h>
@@ -344,6 +345,8 @@ int migrate_page_move_mapping(struct add
 		struct buffer_head *head, enum migrate_mode mode,
 		int extra_count)
 {
+	struct zone *oldzone, *newzone;
+	int dirty;
 	int expected_count = 1 + extra_count;
 	void **pslot;
 
@@ -354,6 +357,9 @@ int migrate_page_move_mapping(struct add
 		return MIGRATEPAGE_SUCCESS;
 	}
 
+	oldzone = page_zone(page);
+	newzone = page_zone(newpage);
+
 	spin_lock_irq(&mapping->tree_lock);
 
 	pslot = radix_tree_lookup_slot(&mapping->page_tree,
@@ -394,6 +400,13 @@ int migrate_page_move_mapping(struct add
 		set_page_private(newpage, page_private(page));
 	}
 
+	/* Move dirty while page refs frozen and newpage not yet exposed */
+	dirty = PageDirty(page);
+	if (dirty) {
+		ClearPageDirty(page);
+		SetPageDirty(newpage);
+	}
+
 	radix_tree_replace_slot(pslot, newpage);
 
 	/*
@@ -403,6 +416,9 @@ int migrate_page_move_mapping(struct add
 	 */
 	page_unfreeze_refs(page, expected_count - 1);
 
+	spin_unlock(&mapping->tree_lock);
+	/* Leave irq disabled to prevent preemption while updating stats */
+
 	/*
 	 * If moved to a different zone then also account
 	 * the page for that zone. Other VM counters will be
@@ -413,13 +429,19 @@ int migrate_page_move_mapping(struct add
 	 * via NR_FILE_PAGES and NR_ANON_PAGES if they
 	 * are mapped to swap space.
 	 */
-	__dec_zone_page_state(page, NR_FILE_PAGES);
-	__inc_zone_page_state(newpage, NR_FILE_PAGES);
-	if (!PageSwapCache(page) && PageSwapBacked(page)) {
-		__dec_zone_page_state(page, NR_SHMEM);
-		__inc_zone_page_state(newpage, NR_SHMEM);
+	if (newzone != oldzone) {
+		__dec_zone_state(oldzone, NR_FILE_PAGES);
+		__inc_zone_state(newzone, NR_FILE_PAGES);
+		if (PageSwapBacked(page) && !PageSwapCache(page)) {
+			__dec_zone_state(oldzone, NR_SHMEM);
+			__inc_zone_state(newzone, NR_SHMEM);
+		}
+		if (dirty && mapping_cap_account_dirty(mapping)) {
+			__dec_zone_state(oldzone, NR_FILE_DIRTY);
+			__inc_zone_state(newzone, NR_FILE_DIRTY);
+		}
 	}
-	spin_unlock_irq(&mapping->tree_lock);
+	local_irq_enable();
 
 	return MIGRATEPAGE_SUCCESS;
 }
@@ -544,20 +566,9 @@ void migrate_page_copy(struct page *newp
 	if (PageMappedToDisk(page))
 		SetPageMappedToDisk(newpage);
 
-	if (PageDirty(page)) {
-		clear_page_dirty_for_io(page);
-		/*
-		 * Want to mark the page and the radix tree as dirty, and
-		 * redo the accounting that clear_page_dirty_for_io undid,
-		 * but we can't use set_page_dirty because that function
-		 * is actually a signal that all of the page has become dirty.
-		 * Whereas only part of our page may be dirty.
-		 */
-		if (PageSwapBacked(page))
-			SetPageDirty(newpage);
-		else
-			__set_page_dirty_nobuffers(newpage);
- 	}
+	/* Move dirty on pages not done by migrate_page_move_mapping() */
+	if (PageDirty(page))
+		SetPageDirty(newpage);
 
 	/*
 	 * Copy NUMA information to the new page, to prevent over-eager

[PATCH 3.14 03/29] printk: do cond_resched() between lines while outputting to consoles

[Greg Kroah-Hartman]

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

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

From: Tejun Heo <tj@kernel.org>

commit 8d91f8b15361dfb438ab6eb3b319e2ded43458ff upstream.

@console_may_schedule tracks whether console_sem was acquired through
lock or trylock.  If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched().  This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.

However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines.  Also, only a few drivers call
console_conditional_schedule() to begin with.  This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.

If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.

Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Calvin Owens <calvinowens@fb.com>
Acked-by: Jan Kara <jack@suse.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ciwillia@brocade.com: adjust context for 3.14.y]
Signed-off-by: Chas Williams <ciwillia@brocade.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/console.h |    1 +
 kernel/panic.c          |    3 +++
 kernel/printk/printk.c  |   35 ++++++++++++++++++++++++++++++++++-
 3 files changed, 38 insertions(+), 1 deletion(-)

--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -150,6 +150,7 @@ extern int console_trylock(void);
 extern void console_unlock(void);
 extern void console_conditional_schedule(void);
 extern void console_unblank(void);
+extern void console_flush_on_panic(void);
 extern struct tty_driver *console_device(int *);
 extern void console_stop(struct console *);
 extern void console_start(struct console *);
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -23,6 +23,7 @@
 #include <linux/sysrq.h>
 #include <linux/init.h>
 #include <linux/nmi.h>
+#include <linux/console.h>
 
 #define PANIC_TIMER_STEP 100
 #define PANIC_BLINK_SPD 18
@@ -133,6 +134,8 @@ void panic(const char *fmt, ...)
 
 	bust_spinlocks(0);
 
+	console_flush_on_panic();
+
 	if (!panic_blink)
 		panic_blink = no_blink;
 
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2011,13 +2011,24 @@ void console_unlock(void)
 	static u64 seen_seq;
 	unsigned long flags;
 	bool wake_klogd = false;
-	bool retry;
+	bool do_cond_resched, retry;
 
 	if (console_suspended) {
 		up(&console_sem);
 		return;
 	}
 
+	/*
+	 * Console drivers are called under logbuf_lock, so
+	 * @console_may_schedule should be cleared before; however, we may
+	 * end up dumping a lot of lines, for example, if called from
+	 * console registration path, and should invoke cond_resched()
+	 * between lines if allowable.  Not doing so can cause a very long
+	 * scheduling stall on a slow console leading to RCU stall and
+	 * softlockup warnings which exacerbate the issue with more
+	 * messages practically incapacitating the system.
+	 */
+	do_cond_resched = console_may_schedule;
 	console_may_schedule = 0;
 
 	/* flush buffered message fragment immediately to console */
@@ -2074,6 +2085,9 @@ skip:
 		call_console_drivers(level, text, len);
 		start_critical_timings();
 		local_irq_restore(flags);
+
+		if (do_cond_resched)
+			cond_resched();
 	}
 	console_locked = 0;
 	mutex_release(&console_lock_dep_map, 1, _RET_IP_);
@@ -2142,6 +2156,25 @@ void console_unblank(void)
 	console_unlock();
 }
 
+/**
+ * console_flush_on_panic - flush console content on panic
+ *
+ * Immediately output all pending messages no matter what.
+ */
+void console_flush_on_panic(void)
+{
+	/*
+	 * If someone else is holding the console lock, trylock will fail
+	 * and may_schedule may be set.  Ignore and proceed to unlock so
+	 * that messages are flushed out.  As this can be called from any
+	 * context and we don't want to get preempted while flushing,
+	 * ensure may_schedule is cleared.
+	 */
+	console_trylock();
+	console_may_schedule = 0;
+	console_unlock();
+}
+
 /*
  * Return the console tty driver structure and its associated index
  */

[PATCH 3.14 04/29] x86/mm: Add barriers and document switch_mm()-vs-flush synchronization

[Greg Kroah-Hartman]

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

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

From: Andy Lutomirski <luto@kernel.org>

commit 71b3c126e61177eb693423f2e18a1914205b165e upstream.

When switch_mm() activates a new PGD, it also sets a bit that
tells other CPUs that the PGD is in use so that TLB flush IPIs
will be sent.  In order for that to work correctly, the bit
needs to be visible prior to loading the PGD and therefore
starting to fill the local TLB.

Document all the barriers that make this work correctly and add
a couple that were missing.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[ luis: backported to 3.16:
  - dropped N/A comment in flush_tlb_mm_range()
  - adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
[ciwillia@brocade.com: backported to 3.14: adjusted context]
Signed-off-by: Charles (Chas) Williams <ciwillia@brocade.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/include/asm/mmu_context.h |   32 +++++++++++++++++++++++++++++++-
 arch/x86/mm/tlb.c                  |   25 ++++++++++++++++++++++---
 2 files changed, 53 insertions(+), 4 deletions(-)

--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -42,7 +42,32 @@ static inline void switch_mm(struct mm_s
 #endif
 		cpumask_set_cpu(cpu, mm_cpumask(next));
 
-		/* Re-load page tables */
+		/*
+		 * Re-load page tables.
+		 *
+		 * This logic has an ordering constraint:
+		 *
+		 *  CPU 0: Write to a PTE for 'next'
+		 *  CPU 0: load bit 1 in mm_cpumask.  if nonzero, send IPI.
+		 *  CPU 1: set bit 1 in next's mm_cpumask
+		 *  CPU 1: load from the PTE that CPU 0 writes (implicit)
+		 *
+		 * We need to prevent an outcome in which CPU 1 observes
+		 * the new PTE value and CPU 0 observes bit 1 clear in
+		 * mm_cpumask.  (If that occurs, then the IPI will never
+		 * be sent, and CPU 0's TLB will contain a stale entry.)
+		 *
+		 * The bad outcome can occur if either CPU's load is
+		 * reordered before that CPU's store, so both CPUs much
+		 * execute full barriers to prevent this from happening.
+		 *
+		 * Thus, switch_mm needs a full barrier between the
+		 * store to mm_cpumask and any operation that could load
+		 * from next->pgd.  This barrier synchronizes with
+		 * remote TLB flushers.  Fortunately, load_cr3 is
+		 * serializing and thus acts as a full barrier.
+		 *
+		 */
 		load_cr3(next->pgd);
 
 		/* Stop flush ipis for the previous mm */
@@ -65,10 +90,15 @@ static inline void switch_mm(struct mm_s
 			 * schedule, protecting us from simultaneous changes.
 			 */
 			cpumask_set_cpu(cpu, mm_cpumask(next));
+
 			/*
 			 * We were in lazy tlb mode and leave_mm disabled
 			 * tlb flush IPI delivery. We must reload CR3
 			 * to make sure to use no freed page tables.
+			 *
+			 * As above, this is a barrier that forces
+			 * TLB repopulation to be ordered after the
+			 * store to mm_cpumask.
 			 */
 			load_cr3(next->pgd);
 			load_LDT_nolock(&next->context);
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -152,7 +152,10 @@ void flush_tlb_current_task(void)
 	preempt_disable();
 
 	count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
+
+	/* This is an implicit full barrier that synchronizes with switch_mm. */
 	local_flush_tlb();
+
 	if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids)
 		flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL);
 	preempt_enable();
@@ -166,11 +169,19 @@ void flush_tlb_mm_range(struct mm_struct
 	unsigned long nr_base_pages;
 
 	preempt_disable();
-	if (current->active_mm != mm)
+	if (current->active_mm != mm) {
+		/* Synchronize with switch_mm. */
+		smp_mb();
+
 		goto flush_all;
+	}
 
 	if (!current->mm) {
 		leave_mm(smp_processor_id());
+
+		/* Synchronize with switch_mm. */
+		smp_mb();
+
 		goto flush_all;
 	}
 
@@ -222,10 +233,18 @@ void flush_tlb_page(struct vm_area_struc
 	preempt_disable();
 
 	if (current->active_mm == mm) {
-		if (current->mm)
+		if (current->mm) {
+			/*
+			 * Implicit full barrier (INVLPG) that synchronizes
+			 * with switch_mm.
+			 */
 			__flush_tlb_one(start);
-		else
+		} else {
 			leave_mm(smp_processor_id());
+
+			/* Synchronize with switch_mm. */
+			smp_mb();
+		}
 	}
 
 	if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids)

[PATCH 3.14 05/29] sctp: Prevent soft lockup when sctp_accept() is called during a timeout event

[Greg Kroah-Hartman]

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

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

From: Karl Heiss <kheiss@gmail.com>

commit 635682a14427d241bab7bbdeebb48a7d7b91638e upstream.

A case can occur when sctp_accept() is called by the user during
a heartbeat timeout event after the 4-way handshake.  Since
sctp_assoc_migrate() changes both assoc->base.sk and assoc->ep, the
bh_sock_lock in sctp_generate_heartbeat_event() will be taken with
the listening socket but released with the new association socket.
The result is a deadlock on any future attempts to take the listening
socket lock.

Note that this race can occur with other SCTP timeouts that take
the bh_lock_sock() in the event sctp_accept() is called.

 BUG: soft lockup - CPU#9 stuck for 67s! [swapper:0]
 ...
 RIP: 0010:[<ffffffff8152d48e>]  [<ffffffff8152d48e>] _spin_lock+0x1e/0x30
 RSP: 0018:ffff880028323b20  EFLAGS: 00000206
 RAX: 0000000000000002 RBX: ffff880028323b20 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: ffff880028323be0 RDI: ffff8804632c4b48
 RBP: ffffffff8100bb93 R08: 0000000000000000 R09: 0000000000000000
 R10: ffff880610662280 R11: 0000000000000100 R12: ffff880028323aa0
 R13: ffff8804383c3880 R14: ffff880028323a90 R15: ffffffff81534225
 FS:  0000000000000000(0000) GS:ffff880028320000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
 CR2: 00000000006df528 CR3: 0000000001a85000 CR4: 00000000000006e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Process swapper (pid: 0, threadinfo ffff880616b70000, task ffff880616b6cab0)
 Stack:
 ffff880028323c40 ffffffffa01c2582 ffff880614cfb020 0000000000000000
 <d> 0100000000000000 00000014383a6c44 ffff8804383c3880 ffff880614e93c00
 <d> ffff880614e93c00 0000000000000000 ffff8804632c4b00 ffff8804383c38b8
 Call Trace:
 <IRQ>
 [<ffffffffa01c2582>] ? sctp_rcv+0x492/0xa10 [sctp]
 [<ffffffff8148c559>] ? nf_iterate+0x69/0xb0
 [<ffffffff814974a0>] ? ip_local_deliver_finish+0x0/0x2d0
 [<ffffffff8148c716>] ? nf_hook_slow+0x76/0x120
 [<ffffffff814974a0>] ? ip_local_deliver_finish+0x0/0x2d0
 [<ffffffff8149757d>] ? ip_local_deliver_finish+0xdd/0x2d0
 [<ffffffff81497808>] ? ip_local_deliver+0x98/0xa0
 [<ffffffff81496ccd>] ? ip_rcv_finish+0x12d/0x440
 [<ffffffff81497255>] ? ip_rcv+0x275/0x350
 [<ffffffff8145cfeb>] ? __netif_receive_skb+0x4ab/0x750
 ...

With lockdep debugging:

 =====================================
 [ BUG: bad unlock balance detected! ]
 -------------------------------------
 CslRx/12087 is trying to release lock (slock-AF_INET) at:
 [<ffffffffa01bcae0>] sctp_generate_timeout_event+0x40/0xe0 [sctp]
 but there are no more locks to release!

 other info that might help us debug this:
 2 locks held by CslRx/12087:
 #0:  (&asoc->timers[i]){+.-...}, at: [<ffffffff8108ce1f>] run_timer_softirq+0x16f/0x3e0
 #1:  (slock-AF_INET){+.-...}, at: [<ffffffffa01bcac3>] sctp_generate_timeout_event+0x23/0xe0 [sctp]

Ensure the socket taken is also the same one that is released by
saving a copy of the socket before entering the timeout event
critical section.

Signed-off-by: Karl Heiss <kheiss@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
(cherry picked from commit 013dd9e038723bbd2aa67be51847384b75be8253)
Signed-off-by: Chas Williams <3chas3@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/sctp/sm_sideeffect.c |   42 +++++++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 19 deletions(-)

--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -244,12 +244,13 @@ void sctp_generate_t3_rtx_event(unsigned
 	int error;
 	struct sctp_transport *transport = (struct sctp_transport *) peer;
 	struct sctp_association *asoc = transport->asoc;
-	struct net *net = sock_net(asoc->base.sk);
+	struct sock *sk = asoc->base.sk;
+	struct net *net = sock_net(sk);
 
 	/* Check whether a task is in the sock.  */
 
-	bh_lock_sock(asoc->base.sk);
-	if (sock_owned_by_user(asoc->base.sk)) {
+	bh_lock_sock(sk);
+	if (sock_owned_by_user(sk)) {
 		pr_debug("%s: sock is busy\n", __func__);
 
 		/* Try again later.  */
@@ -272,10 +273,10 @@ void sctp_generate_t3_rtx_event(unsigned
 			   transport, GFP_ATOMIC);
 
 	if (error)
-		asoc->base.sk->sk_err = -error;
+		sk->sk_err = -error;
 
 out_unlock:
-	bh_unlock_sock(asoc->base.sk);
+	bh_unlock_sock(sk);
 	sctp_transport_put(transport);
 }
 
@@ -285,11 +286,12 @@ out_unlock:
 static void sctp_generate_timeout_event(struct sctp_association *asoc,
 					sctp_event_timeout_t timeout_type)
 {
-	struct net *net = sock_net(asoc->base.sk);
+	struct sock *sk = asoc->base.sk;
+	struct net *net = sock_net(sk);
 	int error = 0;
 
-	bh_lock_sock(asoc->base.sk);
-	if (sock_owned_by_user(asoc->base.sk)) {
+	bh_lock_sock(sk);
+	if (sock_owned_by_user(sk)) {
 		pr_debug("%s: sock is busy: timer %d\n", __func__,
 			 timeout_type);
 
@@ -312,10 +314,10 @@ static void sctp_generate_timeout_event(
 			   (void *)timeout_type, GFP_ATOMIC);
 
 	if (error)
-		asoc->base.sk->sk_err = -error;
+		sk->sk_err = -error;
 
 out_unlock:
-	bh_unlock_sock(asoc->base.sk);
+	bh_unlock_sock(sk);
 	sctp_association_put(asoc);
 }
 
@@ -365,10 +367,11 @@ void sctp_generate_heartbeat_event(unsig
 	int error = 0;
 	struct sctp_transport *transport = (struct sctp_transport *) data;
 	struct sctp_association *asoc = transport->asoc;
-	struct net *net = sock_net(asoc->base.sk);
+	struct sock *sk = asoc->base.sk;
+	struct net *net = sock_net(sk);
 
-	bh_lock_sock(asoc->base.sk);
-	if (sock_owned_by_user(asoc->base.sk)) {
+	bh_lock_sock(sk);
+	if (sock_owned_by_user(sk)) {
 		pr_debug("%s: sock is busy\n", __func__);
 
 		/* Try again later.  */
@@ -389,10 +392,10 @@ void sctp_generate_heartbeat_event(unsig
 			   transport, GFP_ATOMIC);
 
 	 if (error)
-		 asoc->base.sk->sk_err = -error;
+		sk->sk_err = -error;
 
 out_unlock:
-	bh_unlock_sock(asoc->base.sk);
+	bh_unlock_sock(sk);
 	sctp_transport_put(transport);
 }
 
@@ -403,10 +406,11 @@ void sctp_generate_proto_unreach_event(u
 {
 	struct sctp_transport *transport = (struct sctp_transport *) data;
 	struct sctp_association *asoc = transport->asoc;
-	struct net *net = sock_net(asoc->base.sk);
+	struct sock *sk = asoc->base.sk;
+	struct net *net = sock_net(sk);
 
-	bh_lock_sock(asoc->base.sk);
-	if (sock_owned_by_user(asoc->base.sk)) {
+	bh_lock_sock(sk);
+	if (sock_owned_by_user(sk)) {
 		pr_debug("%s: sock is busy\n", __func__);
 
 		/* Try again later.  */
@@ -427,7 +431,7 @@ void sctp_generate_proto_unreach_event(u
 		   asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
 
 out_unlock:
-	bh_unlock_sock(asoc->base.sk);
+	bh_unlock_sock(sk);
 	sctp_association_put(asoc);
 }
 

[PATCH 3.14 06/29] x86/mm: Improve switch_mm() barrier comments

[Greg Kroah-Hartman]

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

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

From: Andy Lutomirski <luto@kernel.org>

commit 4eaffdd5a5fe6ff9f95e1ab4de1ac904d5e0fa8b upstream.

My previous comments were still a bit confusing and there was a
typo. Fix it up.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: 71b3c126e611 ("x86/mm: Add barriers and document switch_mm()-vs-flush synchronization")
Link: http://lkml.kernel.org/r/0a0b43cdcdd241c5faaaecfbcc91a155ddedc9a1.1452631609.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/include/asm/mmu_context.h |   15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -58,14 +58,16 @@ static inline void switch_mm(struct mm_s
 		 * be sent, and CPU 0's TLB will contain a stale entry.)
 		 *
 		 * The bad outcome can occur if either CPU's load is
-		 * reordered before that CPU's store, so both CPUs much
+		 * reordered before that CPU's store, so both CPUs must
 		 * execute full barriers to prevent this from happening.
 		 *
 		 * Thus, switch_mm needs a full barrier between the
 		 * store to mm_cpumask and any operation that could load
-		 * from next->pgd.  This barrier synchronizes with
-		 * remote TLB flushers.  Fortunately, load_cr3 is
-		 * serializing and thus acts as a full barrier.
+		 * from next->pgd.  TLB fills are special and can happen
+		 * due to instruction fetches or for no reason at all,
+		 * and neither LOCK nor MFENCE orders them.
+		 * Fortunately, load_cr3() is serializing and gives the
+		 * ordering guarantee we need.
 		 *
 		 */
 		load_cr3(next->pgd);
@@ -96,9 +98,8 @@ static inline void switch_mm(struct mm_s
 			 * tlb flush IPI delivery. We must reload CR3
 			 * to make sure to use no freed page tables.
 			 *
-			 * As above, this is a barrier that forces
-			 * TLB repopulation to be ordered after the
-			 * store to mm_cpumask.
+			 * As above, load_cr3() is serializing and orders TLB
+			 * fills with respect to the mm_cpumask write.
 			 */
 			load_cr3(next->pgd);
 			load_LDT_nolock(&next->context);

[PATCH 3.14 08/29] USB: fix up incorrect quirk

[Greg Kroah-Hartman]

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

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

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Ben Hutchings reported that commit ddbe1fca0bcb ("USB: Add device quirk
for ASUS T100 Base Station keyboard") was incorrectly ported.

This patch fixes up the quirk by putting it in the correct table.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/core/quirks.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -164,6 +164,10 @@ static const struct usb_device_id usb_qu
 	/* MAYA44USB sound device */
 	{ USB_DEVICE(0x0a92, 0x0091), .driver_info = USB_QUIRK_RESET_RESUME },
 
+	/* ASUS Base Station(T100) */
+	{ USB_DEVICE(0x0b05, 0x17e0), .driver_info =
+			USB_QUIRK_IGNORE_REMOTE_WAKEUP },
+
 	/* Action Semiconductor flash disk */
 	{ USB_DEVICE(0x10d6, 0x2200), .driver_info =
 			USB_QUIRK_STRING_FETCH_255 },
@@ -186,10 +190,6 @@ static const struct usb_device_id usb_in
 	{ USB_VENDOR_AND_INTERFACE_INFO(0x046d, USB_CLASS_VIDEO, 1, 0),
 	  .driver_info = USB_QUIRK_RESET_RESUME },
 
-	/* ASUS Base Station(T100) */
-	{ USB_DEVICE(0x0b05, 0x17e0), .driver_info =
-			USB_QUIRK_IGNORE_REMOTE_WAKEUP },
-
 	{ }  /* terminating entry must be last */
 };
 

[PATCH 3.14 09/29] arm: oabi compat: add missing access checks

[Greg Kroah-Hartman]

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

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

From: Dave Weinstein <olorin@google.com>

commit 7de249964f5578e67b99699c5f0b405738d820a2 upstream.

Add access checks to sys_oabi_epoll_wait() and sys_oabi_semtimedop().
This fixes CVE-2016-3857, a local privilege escalation under
CONFIG_OABI_COMPAT.

Reported-by: Chiachih Wu <wuchiachih@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Dave Weinstein <olorin@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm/kernel/sys_oabi-compat.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/arch/arm/kernel/sys_oabi-compat.c
+++ b/arch/arm/kernel/sys_oabi-compat.c
@@ -275,8 +275,12 @@ asmlinkage long sys_oabi_epoll_wait(int
 	mm_segment_t fs;
 	long ret, err, i;
 
-	if (maxevents <= 0 || maxevents > (INT_MAX/sizeof(struct epoll_event)))
+	if (maxevents <= 0 ||
+			maxevents > (INT_MAX/sizeof(*kbuf)) ||
+			maxevents > (INT_MAX/sizeof(*events)))
 		return -EINVAL;
+	if (!access_ok(VERIFY_WRITE, events, sizeof(*events) * maxevents))
+		return -EFAULT;
 	kbuf = kmalloc(sizeof(*kbuf) * maxevents, GFP_KERNEL);
 	if (!kbuf)
 		return -ENOMEM;
@@ -313,6 +317,8 @@ asmlinkage long sys_oabi_semtimedop(int
 
 	if (nsops < 1 || nsops > SEMOPM)
 		return -EINVAL;
+	if (!access_ok(VERIFY_READ, tsops, sizeof(*tsops) * nsops))
+		return -EFAULT;
 	sops = kmalloc(sizeof(*sops) * nsops, GFP_KERNEL);
 	if (!sops)
 		return -ENOMEM;

[PATCH 3.14 10/29] KEYS: 64-bit MIPS needs to use compat_sys_keyctl for 32-bit userspace

[Greg Kroah-Hartman]

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

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

From: David Howells <dhowells@redhat.com>

commit 20f06ed9f61a185c6dabd662c310bed6189470df upstream.

MIPS64 needs to use compat_sys_keyctl for 32-bit userspace rather than
calling sys_keyctl.  The latter will work in a lot of cases, thereby hiding
the issue.

Reported-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: keyrings@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13832/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/kernel/scall64-n32.S |    2 +-
 arch/mips/kernel/scall64-o32.S |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -350,7 +350,7 @@ EXPORT(sysn32_call_table)
 	PTR	sys_ni_syscall			/* available, was setaltroot */
 	PTR	sys_add_key
 	PTR	sys_request_key
-	PTR	sys_keyctl			/* 6245 */
+	PTR	compat_sys_keyctl		/* 6245 */
 	PTR	sys_set_thread_area
 	PTR	sys_inotify_init
 	PTR	sys_inotify_add_watch
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -474,7 +474,7 @@ EXPORT(sys32_call_table)
 	PTR	sys_ni_syscall			/* available, was setaltroot */
 	PTR	sys_add_key			/* 4280 */
 	PTR	sys_request_key
-	PTR	sys_keyctl
+	PTR	compat_sys_keyctl
 	PTR	sys_set_thread_area
 	PTR	sys_inotify_init
 	PTR	sys_inotify_add_watch		/* 4285 */

[PATCH 3.14 11/29] apparmor: fix ref count leak when profile sha1 hash is read

[Greg Kroah-Hartman]

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

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

From: John Johansen <john.johansen@canonical.com>

commit 0b938a2e2cf0b0a2c8bac9769111545aff0fee97 upstream.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 security/apparmor/apparmorfs.c |    1 +
 1 file changed, 1 insertion(+)

--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -331,6 +331,7 @@ static int aa_fs_seq_hash_show(struct se
 			seq_printf(seq, "%.2x", profile->hash[i]);
 		seq_puts(seq, "\n");
 	}
+	aa_put_profile(profile);
 
 	return 0;
 }

[PATCH 3.14 12/29] random: strengthen input validation for RNDADDTOENTCNT

[Greg Kroah-Hartman]

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

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

From: Theodore Ts'o <tytso@mit.edu>

commit 86a574de4590ffe6fd3f3ca34cdcf655a78e36ec upstream.

Don't allow RNDADDTOENTCNT or RNDADDENTROPY to accept a negative
entropy value.  It doesn't make any sense to subtract from the entropy
counter, and it can trigger a warning:

random: negative entropy/overflow: pool input count -40000
------------[ cut here ]------------
WARNING: CPU: 3 PID: 6828 at drivers/char/random.c:670[<      none
 >] credit_entropy_bits+0x21e/0xad0 drivers/char/random.c:670
Modules linked in:
CPU: 3 PID: 6828 Comm: a.out Not tainted 4.7.0-rc4+ #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffffffff880b58e0 ffff88005dd9fcb0 ffffffff82cc838f ffffffff87158b40
 fffffbfff1016b1c 0000000000000000 0000000000000000 ffffffff87158b40
 ffffffff83283dae 0000000000000009 ffff88005dd9fcf8 ffffffff8136d27f
Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff82cc838f>] dump_stack+0x12e/0x18f lib/dump_stack.c:51
 [<ffffffff8136d27f>] __warn+0x19f/0x1e0 kernel/panic.c:516
 [<ffffffff8136d48c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:551
 [<ffffffff83283dae>] credit_entropy_bits+0x21e/0xad0 drivers/char/random.c:670
 [<     inline     >] credit_entropy_bits_safe drivers/char/random.c:734
 [<ffffffff8328785d>] random_ioctl+0x21d/0x250 drivers/char/random.c:1546
 [<     inline     >] vfs_ioctl fs/ioctl.c:43
 [<ffffffff8185316c>] do_vfs_ioctl+0x18c/0xff0 fs/ioctl.c:674
 [<     inline     >] SYSC_ioctl fs/ioctl.c:689
 [<ffffffff8185405f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:680
 [<ffffffff86a995c0>] entry_SYSCALL_64_fastpath+0x23/0xc1
arch/x86/entry/entry_64.S:207
---[ end trace 5d4902b2ba842f1f ]---

This was triggered using the test program:

// autogenerated by syzkaller (http://github.com/google/syzkaller)

int main() {
        int fd = open("/dev/random", O_RDWR);
        int val = -5000;
        ioctl(fd, RNDADDTOENTCNT, &val);
        return 0;
}

It's harmless in that (a) only root can trigger it, and (b) after
complaining the code never does let the entropy count go negative, but
it's better to simply not allow this userspace from passing in a
negative entropy value altogether.

Google-Bug-Id: #29575089
Reported-By: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/char/random.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -698,15 +698,18 @@ retry:
 	}
 }
 
-static void credit_entropy_bits_safe(struct entropy_store *r, int nbits)
+static int credit_entropy_bits_safe(struct entropy_store *r, int nbits)
 {
 	const int nbits_max = (int)(~0U >> (ENTROPY_SHIFT + 1));
 
+	if (nbits < 0)
+		return -EINVAL;
+
 	/* Cap the value to avoid overflows */
 	nbits = min(nbits,  nbits_max);
-	nbits = max(nbits, -nbits_max);
 
 	credit_entropy_bits(r, nbits);
+	return 0;
 }
 
 /*********************************************************************
@@ -1420,8 +1423,7 @@ static long random_ioctl(struct file *f,
 			return -EPERM;
 		if (get_user(ent_count, p))
 			return -EFAULT;
-		credit_entropy_bits_safe(&input_pool, ent_count);
-		return 0;
+		return credit_entropy_bits_safe(&input_pool, ent_count);
 	case RNDADDENTROPY:
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;
@@ -1435,8 +1437,7 @@ static long random_ioctl(struct file *f,
 				    size);
 		if (retval < 0)
 			return retval;
-		credit_entropy_bits_safe(&input_pool, ent_count);
-		return 0;
+		return credit_entropy_bits_safe(&input_pool, ent_count);
 	case RNDZAPENTCNT:
 	case RNDCLEARPOOL:
 		/*

[PATCH 3.14 13/29] scsi: remove scsi_end_request

[Greg Kroah-Hartman]

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

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

From: Christoph Hellwig <hch@lst.de>

commit bc85dc500f9df9b2eec15077e5046672c46adeaa upstream.

By folding scsi_end_request into its only caller we can significantly clean
up the completion logic.  We can use simple goto labels now to only have
a single place to finish or requeue command there instead of the previous
convoluted logic.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
[jwang: backport to 3.12]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/scsi/scsi_lib.c |  113 +++++++++++++-----------------------------------
 1 file changed, 31 insertions(+), 82 deletions(-)

--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -540,66 +540,6 @@ void scsi_run_host_queues(struct Scsi_Ho
 
 static void __scsi_release_buffers(struct scsi_cmnd *, int);
 
-/*
- * Function:    scsi_end_request()
- *
- * Purpose:     Post-processing of completed commands (usually invoked at end
- *		of upper level post-processing and scsi_io_completion).
- *
- * Arguments:   cmd	 - command that is complete.
- *              error    - 0 if I/O indicates success, < 0 for I/O error.
- *              bytes    - number of bytes of completed I/O
- *		requeue  - indicates whether we should requeue leftovers.
- *
- * Lock status: Assumed that lock is not held upon entry.
- *
- * Returns:     cmd if requeue required, NULL otherwise.
- *
- * Notes:       This is called for block device requests in order to
- *              mark some number of sectors as complete.
- * 
- *		We are guaranteeing that the request queue will be goosed
- *		at some point during this call.
- * Notes:	If cmd was requeued, upon return it will be a stale pointer.
- */
-static struct scsi_cmnd *scsi_end_request(struct scsi_cmnd *cmd, int error,
-					  int bytes, int requeue)
-{
-	struct request_queue *q = cmd->device->request_queue;
-	struct request *req = cmd->request;
-
-	/*
-	 * If there are blocks left over at the end, set up the command
-	 * to queue the remainder of them.
-	 */
-	if (blk_end_request(req, error, bytes)) {
-		/* kill remainder if no retrys */
-		if (error && scsi_noretry_cmd(cmd))
-			blk_end_request_all(req, error);
-		else {
-			if (requeue) {
-				/*
-				 * Bleah.  Leftovers again.  Stick the
-				 * leftovers in the front of the
-				 * queue, and goose the queue again.
-				 */
-				scsi_release_buffers(cmd);
-				scsi_requeue_command(q, cmd);
-				cmd = NULL;
-			}
-			return cmd;
-		}
-	}
-
-	/*
-	 * This will goose the queue request function at the end, so we don't
-	 * need to worry about launching another command.
-	 */
-	__scsi_release_buffers(cmd, 0);
-	scsi_next_command(cmd);
-	return NULL;
-}
-
 static inline unsigned int scsi_sgtable_index(unsigned short nents)
 {
 	unsigned int index;
@@ -751,16 +691,9 @@ static int __scsi_error_from_host_byte(s
  *
  * Returns:     Nothing
  *
- * Notes:       This function is matched in terms of capabilities to
- *              the function that created the scatter-gather list.
- *              In other words, if there are no bounce buffers
- *              (the normal case for most drivers), we don't need
- *              the logic to deal with cleaning up afterwards.
- *
- *		We must call scsi_end_request().  This will finish off
- *		the specified number of sectors.  If we are done, the
- *		command block will be released and the queue function
- *		will be goosed.  If we are not done then we have to
+ * Notes:       We will finish off the specified number of sectors.  If we
+ *		are done, the command block will be released and the queue
+ *		function will be goosed.  If we are not done then we have to
  *		figure out what to do next:
  *
  *		a) We can call scsi_requeue_command().  The request
@@ -769,7 +702,7 @@ static int __scsi_error_from_host_byte(s
  *		   be used if we made forward progress, or if we want
  *		   to switch from READ(10) to READ(6) for example.
  *
- *		b) We can call scsi_queue_insert().  The request will
+ *		b) We can call __scsi_queue_insert().  The request will
  *		   be put back on the queue and retried using the same
  *		   command as before, possibly after a delay.
  *
@@ -873,12 +806,25 @@ void scsi_io_completion(struct scsi_cmnd
 	}
 
 	/*
-	 * A number of bytes were successfully read.  If there
-	 * are leftovers and there is some kind of error
-	 * (result != 0), retry the rest.
+	 * If we finished all bytes in the request we are done now.
 	 */
-	if (scsi_end_request(cmd, error, good_bytes, result == 0) == NULL)
-		return;
+	if (!blk_end_request(req, error, good_bytes))
+		goto next_command;
+
+	/*
+	 * Kill remainder if no retrys.
+	 */
+	if (error && scsi_noretry_cmd(cmd)) {
+		blk_end_request_all(req, error);
+		goto next_command;
+	}
+
+	/*
+	 * If there had been no error, but we have leftover bytes in the
+	 * requeues just queue the command up again.
+	 */
+	if (result == 0)
+		goto requeue;
 
 	error = __scsi_error_from_host_byte(cmd, result);
 
@@ -1000,7 +946,6 @@ void scsi_io_completion(struct scsi_cmnd
 	switch (action) {
 	case ACTION_FAIL:
 		/* Give up and fail the remainder of the request */
-		scsi_release_buffers(cmd);
 		if (!(req->cmd_flags & REQ_QUIET)) {
 			if (description)
 				scmd_printk(KERN_INFO, cmd, "%s\n",
@@ -1010,12 +955,11 @@ void scsi_io_completion(struct scsi_cmnd
 				scsi_print_sense("", cmd);
 			scsi_print_command(cmd);
 		}
-		if (blk_end_request_err(req, error))
-			scsi_requeue_command(q, cmd);
-		else
-			scsi_next_command(cmd);
-		break;
+		if (!blk_end_request_err(req, error))
+			goto next_command;
+		/*FALLTHRU*/
 	case ACTION_REPREP:
+	requeue:
 		/* Unprep the request and put it back at the head of the queue.
 		 * A new command will be prepared and issued.
 		 */
@@ -1031,6 +975,11 @@ void scsi_io_completion(struct scsi_cmnd
 		__scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY, 0);
 		break;
 	}
+	return;
+
+next_command:
+	__scsi_release_buffers(cmd, 0);
+	scsi_next_command(cmd);
 }
 
 static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb,

[PATCH 3.14 14/29] scsi_lib: correctly retry failed zero length REQ_TYPE_FS commands

[Greg Kroah-Hartman]

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

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

From: James Bottomley <James.Bottomley@HansenPartnership.com>

commit a621bac3044ed6f7ec5fa0326491b2d4838bfa93 upstream.

When SCSI was written, all commands coming from the filesystem
(REQ_TYPE_FS commands) had data.  This meant that our signal for needing
to complete the command was the number of bytes completed being equal to
the number of bytes in the request.  Unfortunately, with the advent of
flush barriers, we can now get zero length REQ_TYPE_FS commands, which
confuse this logic because they satisfy the condition every time.  This
means they never get retried even for retryable conditions, like UNIT
ATTENTION because we complete them early assuming they're done.  Fix
this by special casing the early completion condition to recognise zero
length commands with errors and let them drop through to the retry code.

Reported-by: Sebastian Parschauer <s.parschauer@gmx.de>
Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
Tested-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[ jwang: backport from upstream 4.7 to fix scsi resize issue ]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/scsi/scsi_lib.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -806,9 +806,12 @@ void scsi_io_completion(struct scsi_cmnd
 	}
 
 	/*
-	 * If we finished all bytes in the request we are done now.
+	 * special case: failed zero length commands always need to
+	 * drop down into the retry code. Otherwise, if we finished
+	 * all bytes in the request we are done now.
 	 */
-	if (!blk_end_request(req, error, good_bytes))
+	if (!(blk_rq_bytes(req) == 0 && error) &&
+	    !blk_end_request(req, error, good_bytes))
 		goto next_command;
 
 	/*

[PATCH 3.14 15/29] IB/security: Restrict use of the write() interface

[Greg Kroah-Hartman]

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

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

From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

commit e6bd18f57aad1a2d1ef40e646d03ed0f2515c9e3 upstream.

The drivers/infiniband stack uses write() as a replacement for
bi-directional ioctl().  This is not safe. There are ways to
trigger write calls that result in the return structure that
is normally written to user space being shunted off to user
specified kernel memory instead.

For the immediate repair, detect and deny suspicious accesses to
the write API.

For long term, update the user space libraries and the kernel API
to something that doesn't present the same security vulnerabilities
(likely a structured ioctl() interface).

The impacted uAPI interfaces are generally only available if
hardware from drivers/infiniband is installed in the system.

Reported-by: Jann Horn <jann@thejh.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
[ Expanded check to all known write() entry points ]
Signed-off-by: Doug Ledford <dledford@redhat.com>
[ Expanded to include removed ipath driver, and dropped non-existent
  hfi1 driver ]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/infiniband/core/ucm.c                |    4 ++++
 drivers/infiniband/core/ucma.c               |    3 +++
 drivers/infiniband/core/uverbs_main.c        |    5 +++++
 drivers/infiniband/hw/ipath/ipath_file_ops.c |    5 +++++
 drivers/infiniband/hw/qib/qib_file_ops.c     |    5 +++++
 include/rdma/ib.h                            |   16 ++++++++++++++++
 6 files changed, 38 insertions(+)

--- a/drivers/infiniband/core/ucm.c
+++ b/drivers/infiniband/core/ucm.c
@@ -48,6 +48,7 @@
 
 #include <asm/uaccess.h>
 
+#include <rdma/ib.h>
 #include <rdma/ib_cm.h>
 #include <rdma/ib_user_cm.h>
 #include <rdma/ib_marshall.h>
@@ -1104,6 +1105,9 @@ static ssize_t ib_ucm_write(struct file
 	struct ib_ucm_cmd_hdr hdr;
 	ssize_t result;
 
+	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
+		return -EACCES;
+
 	if (len < sizeof(hdr))
 		return -EINVAL;
 
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -1487,6 +1487,9 @@ static ssize_t ucma_write(struct file *f
 	struct rdma_ucm_cmd_hdr hdr;
 	ssize_t ret;
 
+	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
+		return -EACCES;
+
 	if (len < sizeof(hdr))
 		return -EINVAL;
 
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -48,6 +48,8 @@
 
 #include <asm/uaccess.h>
 
+#include <rdma/ib.h>
+
 #include "uverbs.h"
 
 MODULE_AUTHOR("Roland Dreier");
@@ -605,6 +607,9 @@ static ssize_t ib_uverbs_write(struct fi
 	struct ib_uverbs_cmd_hdr hdr;
 	__u32 flags;
 
+	if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
+		return -EACCES;
+
 	if (count < sizeof hdr)
 		return -EINVAL;
 
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -45,6 +45,8 @@
 #include <linux/cpu.h>
 #include <asm/pgtable.h>
 
+#include "rdma/ib.h"
+
 #include "ipath_kernel.h"
 #include "ipath_common.h"
 #include "ipath_user_sdma.h"
@@ -2240,6 +2242,9 @@ static ssize_t ipath_write(struct file *
 	ssize_t ret = 0;
 	void *dest;
 
+	if (WARN_ON_ONCE(!ib_safe_file_access(fp)))
+		return -EACCES;
+
 	if (count < sizeof(cmd.type)) {
 		ret = -EINVAL;
 		goto bail;
--- a/drivers/infiniband/hw/qib/qib_file_ops.c
+++ b/drivers/infiniband/hw/qib/qib_file_ops.c
@@ -45,6 +45,8 @@
 #include <linux/delay.h>
 #include <linux/export.h>
 
+#include <rdma/ib.h>
+
 #include "qib.h"
 #include "qib_common.h"
 #include "qib_user_sdma.h"
@@ -2058,6 +2060,9 @@ static ssize_t qib_write(struct file *fp
 	ssize_t ret = 0;
 	void *dest;
 
+	if (WARN_ON_ONCE(!ib_safe_file_access(fp)))
+		return -EACCES;
+
 	if (count < sizeof(cmd.type)) {
 		ret = -EINVAL;
 		goto bail;
--- a/include/rdma/ib.h
+++ b/include/rdma/ib.h
@@ -34,6 +34,7 @@
 #define _RDMA_IB_H
 
 #include <linux/types.h>
+#include <linux/sched.h>
 
 struct ib_addr {
 	union {
@@ -86,4 +87,19 @@ struct sockaddr_ib {
 	__u64			sib_scope_id;
 };
 
+/*
+ * The IB interfaces that use write() as bi-directional ioctl() are
+ * fundamentally unsafe, since there are lots of ways to trigger "write()"
+ * calls from various contexts with elevated privileges. That includes the
+ * traditional suid executable error message writes, but also various kernel
+ * interfaces that can write to file descriptors.
+ *
+ * This function provides protection for the legacy API by restricting the
+ * calling context.
+ */
+static inline bool ib_safe_file_access(struct file *filp)
+{
+	return filp->f_cred == current_cred() && segment_eq(get_fs(), USER_DS);
+}
+
 #endif /* _RDMA_IB_H */

[PATCH 3.14 16/29] block: fix use-after-free in seq file

[Greg Kroah-Hartman]

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

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

From: Vegard Nossum <vegard.nossum@oracle.com>

commit 77da160530dd1dc94f6ae15a981f24e5f0021e84 upstream.

I got a KASAN report of use-after-free:

    ==================================================================
    BUG: KASAN: use-after-free in klist_iter_exit+0x61/0x70 at addr ffff8800b6581508
    Read of size 8 by task trinity-c1/315
    =============================================================================
    BUG kmalloc-32 (Not tainted): kasan: bad access detected
    -----------------------------------------------------------------------------

    Disabling lock debugging due to kernel taint
    INFO: Allocated in disk_seqf_start+0x66/0x110 age=144 cpu=1 pid=315
            ___slab_alloc+0x4f1/0x520
            __slab_alloc.isra.58+0x56/0x80
            kmem_cache_alloc_trace+0x260/0x2a0
            disk_seqf_start+0x66/0x110
            traverse+0x176/0x860
            seq_read+0x7e3/0x11a0
            proc_reg_read+0xbc/0x180
            do_loop_readv_writev+0x134/0x210
            do_readv_writev+0x565/0x660
            vfs_readv+0x67/0xa0
            do_preadv+0x126/0x170
            SyS_preadv+0xc/0x10
            do_syscall_64+0x1a1/0x460
            return_from_SYSCALL_64+0x0/0x6a
    INFO: Freed in disk_seqf_stop+0x42/0x50 age=160 cpu=1 pid=315
            __slab_free+0x17a/0x2c0
            kfree+0x20a/0x220
            disk_seqf_stop+0x42/0x50
            traverse+0x3b5/0x860
            seq_read+0x7e3/0x11a0
            proc_reg_read+0xbc/0x180
            do_loop_readv_writev+0x134/0x210
            do_readv_writev+0x565/0x660
            vfs_readv+0x67/0xa0
            do_preadv+0x126/0x170
            SyS_preadv+0xc/0x10
            do_syscall_64+0x1a1/0x460
            return_from_SYSCALL_64+0x0/0x6a

    CPU: 1 PID: 315 Comm: trinity-c1 Tainted: G    B           4.7.0+ #62
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
     ffffea0002d96000 ffff880119b9f918 ffffffff81d6ce81 ffff88011a804480
     ffff8800b6581500 ffff880119b9f948 ffffffff8146c7bd ffff88011a804480
     ffffea0002d96000 ffff8800b6581500 fffffffffffffff4 ffff880119b9f970
    Call Trace:
     [<ffffffff81d6ce81>] dump_stack+0x65/0x84
     [<ffffffff8146c7bd>] print_trailer+0x10d/0x1a0
     [<ffffffff814704ff>] object_err+0x2f/0x40
     [<ffffffff814754d1>] kasan_report_error+0x221/0x520
     [<ffffffff8147590e>] __asan_report_load8_noabort+0x3e/0x40
     [<ffffffff83888161>] klist_iter_exit+0x61/0x70
     [<ffffffff82404389>] class_dev_iter_exit+0x9/0x10
     [<ffffffff81d2e8ea>] disk_seqf_stop+0x3a/0x50
     [<ffffffff8151f812>] seq_read+0x4b2/0x11a0
     [<ffffffff815f8fdc>] proc_reg_read+0xbc/0x180
     [<ffffffff814b24e4>] do_loop_readv_writev+0x134/0x210
     [<ffffffff814b4c45>] do_readv_writev+0x565/0x660
     [<ffffffff814b8a17>] vfs_readv+0x67/0xa0
     [<ffffffff814b8de6>] do_preadv+0x126/0x170
     [<ffffffff814b92ec>] SyS_preadv+0xc/0x10

This problem can occur in the following situation:

open()
 - pread()
    - .seq_start()
       - iter = kmalloc() // succeeds
       - seqf->private = iter
    - .seq_stop()
       - kfree(seqf->private)
 - pread()
    - .seq_start()
       - iter = kmalloc() // fails
    - .seq_stop()
       - class_dev_iter_exit(seqf->private) // boom! old pointer

As the comment in disk_seqf_stop() says, stop is called even if start
failed, so we need to reinitialise the private pointer to NULL when seq
iteration stops.

An alternative would be to set the private pointer to NULL when the
kmalloc() in disk_seqf_start() fails.

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 block/genhd.c |    1 +
 1 file changed, 1 insertion(+)

--- a/block/genhd.c
+++ b/block/genhd.c
@@ -829,6 +829,7 @@ static void disk_seqf_stop(struct seq_fi
 	if (iter) {
 		class_dev_iter_exit(iter);
 		kfree(iter);
+		seqf->private = NULL;
 	}
 }
 

[PATCH 3.14 17/29] sysv, ipc: fix security-layer leaking

[Greg Kroah-Hartman]

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

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

From: Fabian Frederick <fabf@skynet.be>

commit 9b24fef9f0410fb5364245d6cc2bd044cc064007 upstream.

Commit 53dad6d3a8e5 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
to receive rcu freeing function but used generic ipc_rcu_free() instead
of msg_rcu_free() which does security cleaning.

Running LTP msgsnd06 with kmemleak gives the following:

  cat /sys/kernel/debug/kmemleak

  unreferenced object 0xffff88003c0a11f8 (size 8):
    comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
    hex dump (first 8 bytes):
      1b 00 00 00 01 00 00 00                          ........
    backtrace:
      kmemleak_alloc+0x23/0x40
      kmem_cache_alloc_trace+0xe1/0x180
      selinux_msg_queue_alloc_security+0x3f/0xd0
      security_msg_queue_alloc+0x2e/0x40
      newque+0x4e/0x150
      ipcget+0x159/0x1b0
      SyS_msgget+0x39/0x40
      entry_SYSCALL_64_fastpath+0x13/0x8f

Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
only use ipc_rcu_free in case of security allocation failure in newary()

Fixes: 53dad6d3a8e ("ipc: fix race with LSMs")
Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 ipc/msg.c |    2 +-
 ipc/sem.c |   12 ++++++------
 2 files changed, 7 insertions(+), 7 deletions(-)

--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -745,7 +745,7 @@ long do_msgsnd(int msqid, long mtype, vo
 		rcu_read_lock();
 		ipc_lock_object(&msq->q_perm);
 
-		ipc_rcu_putref(msq, ipc_rcu_free);
+		ipc_rcu_putref(msq, msg_rcu_free);
 		/* raced with RMID? */
 		if (!ipc_valid_object(&msq->q_perm)) {
 			err = -EIDRM;
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -441,7 +441,7 @@ static inline struct sem_array *sem_obta
 static inline void sem_lock_and_putref(struct sem_array *sma)
 {
 	sem_lock(sma, NULL, -1);
-	ipc_rcu_putref(sma, ipc_rcu_free);
+	ipc_rcu_putref(sma, sem_rcu_free);
 }
 
 static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
@@ -1371,7 +1371,7 @@ static int semctl_main(struct ipc_namesp
 			rcu_read_unlock();
 			sem_io = ipc_alloc(sizeof(ushort)*nsems);
 			if (sem_io == NULL) {
-				ipc_rcu_putref(sma, ipc_rcu_free);
+				ipc_rcu_putref(sma, sem_rcu_free);
 				return -ENOMEM;
 			}
 
@@ -1405,20 +1405,20 @@ static int semctl_main(struct ipc_namesp
 		if (nsems > SEMMSL_FAST) {
 			sem_io = ipc_alloc(sizeof(ushort)*nsems);
 			if (sem_io == NULL) {
-				ipc_rcu_putref(sma, ipc_rcu_free);
+				ipc_rcu_putref(sma, sem_rcu_free);
 				return -ENOMEM;
 			}
 		}
 
 		if (copy_from_user(sem_io, p, nsems*sizeof(ushort))) {
-			ipc_rcu_putref(sma, ipc_rcu_free);
+			ipc_rcu_putref(sma, sem_rcu_free);
 			err = -EFAULT;
 			goto out_free;
 		}
 
 		for (i = 0; i < nsems; i++) {
 			if (sem_io[i] > SEMVMX) {
-				ipc_rcu_putref(sma, ipc_rcu_free);
+				ipc_rcu_putref(sma, sem_rcu_free);
 				err = -ERANGE;
 				goto out_free;
 			}
@@ -1708,7 +1708,7 @@ static struct sem_undo *find_alloc_undo(
 	/* step 2: allocate new undo structure */
 	new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL);
 	if (!new) {
-		ipc_rcu_putref(sma, ipc_rcu_free);
+		ipc_rcu_putref(sma, sem_rcu_free);
 		return ERR_PTR(-ENOMEM);
 	}
 

Re: [PATCH 3.14 17/29] sysv, ipc: fix security-layer leaking

[Willy Tarreau]

Hi guys,

On Sun, Aug 14, 2016 at 10:07:45PM +0200, Greg Kroah-Hartman wrote:
> 3.14-stable review patch.  If anyone has any objections, please let me know.
> 
> ------------------
> 
> From: Fabian Frederick <fabf@skynet.be>
> 
> commit 9b24fef9f0410fb5364245d6cc2bd044cc064007 upstream.
> 
> Commit 53dad6d3a8e5 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
> to receive rcu freeing function but used generic ipc_rcu_free() instead
> of msg_rcu_free() which does security cleaning.
> 
> Running LTP msgsnd06 with kmemleak gives the following:
> 
>   cat /sys/kernel/debug/kmemleak
> 
>   unreferenced object 0xffff88003c0a11f8 (size 8):
>     comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
>     hex dump (first 8 bytes):
>       1b 00 00 00 01 00 00 00                          ........
>     backtrace:
>       kmemleak_alloc+0x23/0x40
>       kmem_cache_alloc_trace+0xe1/0x180
>       selinux_msg_queue_alloc_security+0x3f/0xd0
>       security_msg_queue_alloc+0x2e/0x40
>       newque+0x4e/0x150
>       ipcget+0x159/0x1b0
>       SyS_msgget+0x39/0x40
>       entry_SYSCALL_64_fastpath+0x13/0x8f
> 
> Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
> only use ipc_rcu_free in case of security allocation failure in newary()
> 
> Fixes: 53dad6d3a8e ("ipc: fix race with LSMs")
> Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.be
> Signed-off-by: Fabian Frederick <fabf@skynet.be>
> Cc: Davidlohr Bueso <dbueso@suse.de>
> Cc: Manfred Spraul <manfred@colorfullife.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The patch above was tagged for stable v3.12+, however it references a fix
that was backported in 3.10.16 as commit e84ca333, so I'm unsure whether
3.10 is affected or not. It *seems* to me that I should replace remaining
instances of ipc_rcu_free with sem_rcu_free in sem.c, and with msg_rcu_free
in msg.c, but I'd prefer a confirmation. For now I'm postponing this fix,
any hint would be much appreciated.

Thanks,
Willy

Re: [PATCH 3.14 17/29] sysv, ipc: fix security-layer leaking

[Manfred Spraul]

Hi Willy,

On 08/21/2016 01:49 PM, Willy Tarreau wrote:
> Hi guys,
>
> On Sun, Aug 14, 2016 at 10:07:45PM +0200, Greg Kroah-Hartman wrote:
>> 3.14-stable review patch.  If anyone has any objections, please let me know.
>>
>> ------------------
>>
>> From: Fabian Frederick <fabf@skynet.be>
>>
>> commit 9b24fef9f0410fb5364245d6cc2bd044cc064007 upstream.
>>
>> Commit 53dad6d3a8e5 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
>> to receive rcu freeing function but used generic ipc_rcu_free() instead
>> of msg_rcu_free() which does security cleaning.
>>
>> Running LTP msgsnd06 with kmemleak gives the following:
>>
>>    cat /sys/kernel/debug/kmemleak
>>
>>    unreferenced object 0xffff88003c0a11f8 (size 8):
>>      comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
>>      hex dump (first 8 bytes):
>>        1b 00 00 00 01 00 00 00                          ........
>>      backtrace:
>>        kmemleak_alloc+0x23/0x40
>>        kmem_cache_alloc_trace+0xe1/0x180
>>        selinux_msg_queue_alloc_security+0x3f/0xd0
>>        security_msg_queue_alloc+0x2e/0x40
>>        newque+0x4e/0x150
>>        ipcget+0x159/0x1b0
>>        SyS_msgget+0x39/0x40
>>        entry_SYSCALL_64_fastpath+0x13/0x8f
>>
>> Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
>> only use ipc_rcu_free in case of security allocation failure in newary()
>>
>> Fixes: 53dad6d3a8e ("ipc: fix race with LSMs")
>> Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.be
>> Signed-off-by: Fabian Frederick <fabf@skynet.be>
>> Cc: Davidlohr Bueso <dbueso@suse.de>
>> Cc: Manfred Spraul <manfred@colorfullife.com>
>> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
>> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
>> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> The patch above was tagged for stable v3.12+, however it references a fix
> that was backported in 3.10.16 as commit e84ca333, so I'm unsure whether
> 3.10 is affected or not. It *seems* to me that I should replace remaining
> instances of ipc_rcu_free with sem_rcu_free in sem.c, and with msg_rcu_free
> in msg.c, but I'd prefer a confirmation. For now I'm postponing this fix,
> any hint would be much appreciated.
Yes, we need the patch for v3.10 as well.
There must be exactly two instances of ipc_rcu_free in each of sem.c, 
msg.c, shm.c:
It is called when security_{sem,msg_queue,shm}_alloc fails.
And obviously within sem_rcu_free, ... .

The rest must be sem_rcu_free(), ... .

Should I test if the patch from 3.14 works with v3.10?

--
     Manfred

Re: [PATCH 3.14 17/29] sysv, ipc: fix security-layer leaking

[Willy Tarreau]

Hi Manfred,

On Mon, Aug 29, 2016 at 11:23:55AM +0200, Manfred Spraul wrote:
> Hi Willy,
> 
> On 08/21/2016 01:49 PM, Willy Tarreau wrote:
> > Hi guys,
> > 
> > On Sun, Aug 14, 2016 at 10:07:45PM +0200, Greg Kroah-Hartman wrote:
> > > 3.14-stable review patch.  If anyone has any objections, please let me know.
> > > 
> > > ------------------
> > > 
> > > From: Fabian Frederick <fabf@skynet.be>
> > > 
> > > commit 9b24fef9f0410fb5364245d6cc2bd044cc064007 upstream.
> > > 
> > > Commit 53dad6d3a8e5 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
> > > to receive rcu freeing function but used generic ipc_rcu_free() instead
> > > of msg_rcu_free() which does security cleaning.
> > > 
> > > Running LTP msgsnd06 with kmemleak gives the following:
> > > 
> > >    cat /sys/kernel/debug/kmemleak
> > > 
> > >    unreferenced object 0xffff88003c0a11f8 (size 8):
> > >      comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
> > >      hex dump (first 8 bytes):
> > >        1b 00 00 00 01 00 00 00                          ........
> > >      backtrace:
> > >        kmemleak_alloc+0x23/0x40
> > >        kmem_cache_alloc_trace+0xe1/0x180
> > >        selinux_msg_queue_alloc_security+0x3f/0xd0
> > >        security_msg_queue_alloc+0x2e/0x40
> > >        newque+0x4e/0x150
> > >        ipcget+0x159/0x1b0
> > >        SyS_msgget+0x39/0x40
> > >        entry_SYSCALL_64_fastpath+0x13/0x8f
> > > 
> > > Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
> > > only use ipc_rcu_free in case of security allocation failure in newary()
> > > 
> > > Fixes: 53dad6d3a8e ("ipc: fix race with LSMs")
> > > Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.be
> > > Signed-off-by: Fabian Frederick <fabf@skynet.be>
> > > Cc: Davidlohr Bueso <dbueso@suse.de>
> > > Cc: Manfred Spraul <manfred@colorfullife.com>
> > > Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> > > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
> > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > The patch above was tagged for stable v3.12+, however it references a fix
> > that was backported in 3.10.16 as commit e84ca333, so I'm unsure whether
> > 3.10 is affected or not. It *seems* to me that I should replace remaining
> > instances of ipc_rcu_free with sem_rcu_free in sem.c, and with msg_rcu_free
> > in msg.c, but I'd prefer a confirmation. For now I'm postponing this fix,
> > any hint would be much appreciated.
> Yes, we need the patch for v3.10 as well.
> There must be exactly two instances of ipc_rcu_free in each of sem.c, msg.c,
> shm.c:
> It is called when security_{sem,msg_queue,shm}_alloc fails.
> And obviously within sem_rcu_free, ... .
> 
> The rest must be sem_rcu_free(), ... .

OK that seems clear enough.

> Should I test if the patch from 3.14 works with v3.10?

As you like. Your explanation seems clear to me, I think I'll get it
right. However if you have an easy reproducer and don't mind testing
it on 3.10.103, that would indeed be appreciated, otherwise do not
waste your time.

thanks,
Willy

[PATCH 3.14 18/29] fuse: fix wrong assignment of ->flags in fuse_send_init()

[Greg Kroah-Hartman]

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

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

From: Wei Fang <fangwei1@huawei.com>

commit 9446385f05c9af25fed53dbed3cc75763730be52 upstream.

FUSE_HAS_IOCTL_DIR should be assigned to ->flags, it may be a typo.

Signed-off-by: Wei Fang <fangwei1@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 69fe05c90ed5 ("fuse: add missing INIT flags")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -911,7 +911,7 @@ static void fuse_send_init(struct fuse_c
 	arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
 		FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
 		FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
-		FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
+		FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
 		FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO;
 	req->in.h.opcode = FUSE_INIT;
 	req->in.numargs = 1;

[PATCH 3.14 19/29] crypto: gcm - Filter out async ghash if necessary

[Greg Kroah-Hartman]

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

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

From: Herbert Xu <herbert@gondor.apana.org.au>

commit b30bdfa86431afbafe15284a3ad5ac19b49b88e3 upstream.

As it is if you ask for a sync gcm you may actually end up with
an async one because it does not filter out async implementations
of ghash.

This patch fixes this by adding the necessary filter when looking
for ghash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 crypto/gcm.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/crypto/gcm.c
+++ b/crypto/gcm.c
@@ -716,7 +716,9 @@ static struct crypto_instance *crypto_gc
 
 	ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
 				    CRYPTO_ALG_TYPE_HASH,
-				    CRYPTO_ALG_TYPE_AHASH_MASK);
+				    CRYPTO_ALG_TYPE_AHASH_MASK |
+				    crypto_requires_sync(algt->type,
+							 algt->mask));
 	if (IS_ERR(ghash_alg))
 		return ERR_CAST(ghash_alg);
 

[PATCH 3.14 20/29] crypto: scatterwalk - Fix test in scatterwalk_done

[Greg Kroah-Hartman]

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

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

From: Herbert Xu <herbert@gondor.apana.org.au>

commit 5f070e81bee35f1b7bd1477bb223a873ff657803 upstream.

When there is more data to be processed, the current test in
scatterwalk_done may prevent us from calling pagedone even when
we should.

In particular, if we're on an SG entry spanning multiple pages
where the last page is not a full page, we will incorrectly skip
calling pagedone on the second last page.

This patch fixes this by adding a separate test for whether we've
reached the end of a page.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 crypto/scatterwalk.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/crypto/scatterwalk.c
+++ b/crypto/scatterwalk.c
@@ -68,7 +68,8 @@ static void scatterwalk_pagedone(struct
 
 void scatterwalk_done(struct scatter_walk *walk, int out, int more)
 {
-	if (!(scatterwalk_pagelen(walk) & (PAGE_SIZE - 1)) || !more)
+	if (!more || walk->offset >= walk->sg->offset + walk->sg->length ||
+	    !(walk->offset & (PAGE_SIZE - 1)))
 		scatterwalk_pagedone(walk, out, more);
 }
 EXPORT_SYMBOL_GPL(scatterwalk_done);

[PATCH 3.14 21/29] ext4: check for extents that wrap around

[Greg Kroah-Hartman]

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

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

From: Vegard Nossum <vegard.nossum@oracle.com>

commit f70749ca42943faa4d4dcce46dfdcaadb1d0c4b6 upstream.

An extent with lblock = 4294967295 and len = 1 will pass the
ext4_valid_extent() test:

	ext4_lblk_t last = lblock + len - 1;

	if (len == 0 || lblock > last)
		return 0;

since last = 4294967295 + 1 - 1 = 4294967295. This would later trigger
the BUG_ON(es->es_lblk + es->es_len < es->es_lblk) in ext4_es_end().

We can simplify it by removing the - 1 altogether and changing the test
to use lblock + len <= lblock, since now if len = 0, then lblock + 0 ==
lblock and it fails, and if len > 0 then lblock + len > lblock in order
to pass (i.e. it doesn't overflow).

Fixes: 5946d0893 ("ext4: check for overlapping extents in ext4_valid_extent_entries()")
Fixes: 2f974865f ("ext4: check for zero length extent explicitly")
Cc: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -359,9 +359,13 @@ static int ext4_valid_extent(struct inod
 	ext4_fsblk_t block = ext4_ext_pblock(ext);
 	int len = ext4_ext_get_actual_len(ext);
 	ext4_lblk_t lblock = le32_to_cpu(ext->ee_block);
-	ext4_lblk_t last = lblock + len - 1;
 
-	if (len == 0 || lblock > last)
+	/*
+	 * We allow neither:
+	 *  - zero length
+	 *  - overflow/wrap-around
+	 */
+	if (lblock + len <= lblock)
 		return 0;
 	return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
 }

[PATCH 3.14 22/29] ext4: fix deadlock during page writeback

[Greg Kroah-Hartman]

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

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

From: Jan Kara <jack@suse.cz>

commit 646caa9c8e196880b41cd3e3d33a2ebc752bdb85 upstream.

Commit 06bd3c36a733 (ext4: fix data exposure after a crash) uncovered a
deadlock in ext4_writepages() which was previously much harder to hit.
After this commit xfstest generic/130 reproduces the deadlock on small
filesystems.

The problem happens when ext4_do_update_inode() sets LARGE_FILE feature
and marks current inode handle as synchronous. That subsequently results
in ext4_journal_stop() called from ext4_writepages() to block waiting for
transaction commit while still holding page locks, reference to io_end,
and some prepared bio in mpd structure each of which can possibly block
transaction commit from completing and thus results in deadlock.

Fix the problem by releasing page locks, io_end reference, and
submitting prepared bio before calling ext4_journal_stop().

[ Changed to defer the call to ext4_journal_stop() only if the handle
  is synchronous.  --tytso ]

Reported-and-tested-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/ext4/inode.c |   29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2579,13 +2579,36 @@ retry:
 				done = true;
 			}
 		}
-		ext4_journal_stop(handle);
+		/*
+		 * Caution: If the handle is synchronous,
+		 * ext4_journal_stop() can wait for transaction commit
+		 * to finish which may depend on writeback of pages to
+		 * complete or on page lock to be released.  In that
+		 * case, we have to wait until after after we have
+		 * submitted all the IO, released page locks we hold,
+		 * and dropped io_end reference (for extent conversion
+		 * to be able to complete) before stopping the handle.
+		 */
+		if (!ext4_handle_valid(handle) || handle->h_sync == 0) {
+			ext4_journal_stop(handle);
+			handle = NULL;
+		}
 		/* Submit prepared bio */
 		ext4_io_submit(&mpd.io_submit);
 		/* Unlock pages we didn't use */
 		mpage_release_unused_pages(&mpd, give_up_on_write);
-		/* Drop our io_end reference we got from init */
-		ext4_put_io_end(mpd.io_submit.io_end);
+		/*
+		 * Drop our io_end reference we got from init. We have
+		 * to be careful and use deferred io_end finishing if
+		 * we are still holding the transaction as we can
+		 * release the last reference to io_end which may end
+		 * up doing unwritten extent conversion.
+		 */
+		if (handle) {
+			ext4_put_io_end_defer(mpd.io_submit.io_end);
+			ext4_journal_stop(handle);
+		} else
+			ext4_put_io_end(mpd.io_submit.io_end);
 
 		if (ret == -ENOSPC && sbi->s_journal) {
 			/*

[PATCH 3.14 23/29] ext4: dont call ext4_should_journal_data() on the journal inode

[Greg Kroah-Hartman]

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

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

From: Vegard Nossum <vegard.nossum@oracle.com>

commit 6a7fd522a7c94cdef0a3b08acf8e6702056e635c upstream.

If ext4_fill_super() fails early, it's possible for ext4_evict_inode()
to call ext4_should_journal_data() before superblock options and flags
are fully set up.  In that case, the iput() on the journal inode can
end up causing a BUG().

Work around this problem by reordering the tests so we only call
ext4_should_journal_data() after we know it's not the journal inode.

Fixes: 2d859db3e4 ("ext4: fix data corruption in inodes with journalled data")
Fixes: 2b405bfa84 ("ext4: fix data=journal fast mount/umount hang")
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/ext4/inode.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -204,9 +204,9 @@ void ext4_evict_inode(struct inode *inod
 		 * Note that directories do not have this problem because they
 		 * don't use page cache.
 		 */
-		if (ext4_should_journal_data(inode) &&
-		    (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) &&
-		    inode->i_ino != EXT4_JOURNAL_INO) {
+		if (inode->i_ino != EXT4_JOURNAL_INO &&
+		    ext4_should_journal_data(inode) &&
+		    (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) {
 			journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
 			tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;
 

[PATCH 3.14 24/29] ext4: short-cut orphan cleanup on error

[Greg Kroah-Hartman]

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

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

From: Vegard Nossum <vegard.nossum@oracle.com>

commit c65d5c6c81a1f27dec5f627f67840726fcd146de upstream.

If we encounter a filesystem error during orphan cleanup, we should stop.
Otherwise, we may end up in an infinite loop where the same inode is
processed again and again.

    EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended
    EXT4-fs error (device loop0): ext4_mb_generate_buddy:758: group 2, block bitmap and bg descriptor inconsistent: 6117 vs 0 free clusters
    Aborting journal on device loop0-8.
    EXT4-fs (loop0): Remounting filesystem read-only
    EXT4-fs error (device loop0) in ext4_free_blocks:4895: Journal has aborted
    EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
    EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
    EXT4-fs error (device loop0) in ext4_ext_remove_space:3068: IO failure
    EXT4-fs error (device loop0) in ext4_ext_truncate:4667: Journal has aborted
    EXT4-fs error (device loop0) in ext4_orphan_del:2927: Journal has aborted
    EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
    EXT4-fs (loop0): Inode 16 (00000000618192a0): orphan list check failed!
    [...]
    EXT4-fs (loop0): Inode 16 (0000000061819748): orphan list check failed!
    [...]
    EXT4-fs (loop0): Inode 16 (0000000061819bf0): orphan list check failed!
    [...]

See-also: c9eb13a9105 ("ext4: fix hang when processing corrupted orphaned inode list")
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/ext4/super.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2222,6 +2222,16 @@ static void ext4_orphan_cleanup(struct s
 	while (es->s_last_orphan) {
 		struct inode *inode;
 
+		/*
+		 * We may have encountered an error during cleanup; if
+		 * so, skip the rest.
+		 */
+		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
+			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
+			es->s_last_orphan = 0;
+			break;
+		}
+
 		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
 		if (IS_ERR(inode)) {
 			es->s_last_orphan = 0;

[PATCH 3.14 25/29] bonding: set carrier off for devices created through netlink

[Greg Kroah-Hartman]

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

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

From: Beniamino Galvani <bgalvani@redhat.com>

[ Upstream commit 005db31d5f5f7c31cfdc43505d77eb3ca5cf8ec6 ]

Commit e826eafa65c6 ("bonding: Call netif_carrier_off after
register_netdevice") moved netif_carrier_off() from bond_init() to
bond_create(), but the latter is called only for initial default
devices and ones created through sysfs:

 $ modprobe bonding
 $ echo +bond1 > /sys/class/net/bonding_masters
 $ ip link add bond2 type bond
 $ grep "MII Status" /proc/net/bonding/*
 /proc/net/bonding/bond0:MII Status: down
 /proc/net/bonding/bond1:MII Status: down
 /proc/net/bonding/bond2:MII Status: up

Ensure that carrier is initially off also for devices created through
netlink.

Signed-off-by: Beniamino Galvani <bgalvani@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/bonding/bond_netlink.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/net/bonding/bond_netlink.c
+++ b/drivers/net/bonding/bond_netlink.c
@@ -360,7 +360,11 @@ static int bond_newlink(struct net *src_
 	if (err < 0)
 		return err;
 
-	return register_netdevice(bond_dev);
+	err = register_netdevice(bond_dev);
+
+	netif_carrier_off(bond_dev);
+
+	return err;
 }
 
 static size_t bond_get_size(const struct net_device *bond_dev)

[PATCH 3.14 26/29] net/irda: fix NULL pointer dereference on memory allocation failure

[Greg Kroah-Hartman]

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

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

From: Vegard Nossum <vegard.nossum@oracle.com>

[ Upstream commit d3e6952cfb7ba5f4bfa29d4803ba91f96ce1204d ]

I ran into this:

    kasan: CONFIG_KASAN_INLINE enabled
    kasan: GPF could be caused by NULL-ptr deref or user memory access
    general protection fault: 0000 [#1] PREEMPT SMP KASAN
    CPU: 2 PID: 2012 Comm: trinity-c3 Not tainted 4.7.0-rc7+ #19
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
    task: ffff8800b745f2c0 ti: ffff880111740000 task.ti: ffff880111740000
    RIP: 0010:[<ffffffff82bbf066>]  [<ffffffff82bbf066>] irttp_connect_request+0x36/0x710
    RSP: 0018:ffff880111747bb8  EFLAGS: 00010286
    RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000069dd8358
    RDX: 0000000000000009 RSI: 0000000000000027 RDI: 0000000000000048
    RBP: ffff880111747c00 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000069dd8358 R11: 1ffffffff0759723 R12: 0000000000000000
    R13: ffff88011a7e4780 R14: 0000000000000027 R15: 0000000000000000
    FS:  00007fc738404700(0000) GS:ffff88011af00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007fc737fdfb10 CR3: 0000000118087000 CR4: 00000000000006e0
    Stack:
     0000000000000200 ffff880111747bd8 ffffffff810ee611 ffff880119f1f220
     ffff880119f1f4f8 ffff880119f1f4f0 ffff88011a7e4780 ffff880119f1f232
     ffff880119f1f220 ffff880111747d58 ffffffff82bca542 0000000000000000
    Call Trace:
     [<ffffffff82bca542>] irda_connect+0x562/0x1190
     [<ffffffff825ae582>] SYSC_connect+0x202/0x2a0
     [<ffffffff825b4489>] SyS_connect+0x9/0x10
     [<ffffffff8100334c>] do_syscall_64+0x19c/0x410
     [<ffffffff83295ca5>] entry_SYSCALL64_slow_path+0x25/0x25
    Code: 41 89 ca 48 89 e5 41 57 41 56 41 55 41 54 41 89 d7 53 48 89 fb 48 83 c7 48 48 89 fa 41 89 f6 48 c1 ea 03 48 83 ec 20 4c 8b 65 10 <0f> b6 04 02 84 c0 74 08 84 c0 0f 8e 4c 04 00 00 80 7b 48 00 74
    RIP  [<ffffffff82bbf066>] irttp_connect_request+0x36/0x710
     RSP <ffff880111747bb8>
    ---[ end trace 4cda2588bc055b30 ]---

The problem is that irda_open_tsap() can fail and leave self->tsap = NULL,
and then irttp_connect_request() almost immediately dereferences it.

Cc: stable@vger.kernel.org
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/irda/af_irda.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/net/irda/af_irda.c
+++ b/net/irda/af_irda.c
@@ -1037,8 +1037,11 @@ static int irda_connect(struct socket *s
 	}
 
 	/* Check if we have opened a local TSAP */
-	if (!self->tsap)
-		irda_open_tsap(self, LSAP_ANY, addr->sir_name);
+	if (!self->tsap) {
+		err = irda_open_tsap(self, LSAP_ANY, addr->sir_name);
+		if (err)
+			goto out;
+	}
 
 	/* Move to connecting socket, start sending Connect Requests */
 	sock->state = SS_CONNECTING;

[PATCH 3.14 27/29] tcp: consider recv buf for the initial window scale

[Greg Kroah-Hartman]

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

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

From: Soheil Hassas Yeganeh <soheil@google.com>

[ Upstream commit f626300a3e776ccc9671b0dd94698fb3aa315966 ]

tcp_select_initial_window() intends to advertise a window
scaling for the maximum possible window size. To do so,
it considers the maximum of net.ipv4.tcp_rmem[2] and
net.core.rmem_max as the only possible upper-bounds.
However, users with CAP_NET_ADMIN can use SO_RCVBUFFORCE
to set the socket's receive buffer size to values
larger than net.ipv4.tcp_rmem[2] and net.core.rmem_max.
Thus, SO_RCVBUFFORCE is effectively ignored by
tcp_select_initial_window().

To fix this, consider the maximum of net.ipv4.tcp_rmem[2],
net.core.rmem_max and socket's initial buffer space.

Fixes: b0573dea1fb3 ("[NET]: Introduce SO_{SND,RCV}BUFFORCE socket options")
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Suggested-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_output.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -242,7 +242,8 @@ void tcp_select_initial_window(int __spa
 		/* Set window scaling on max possible window
 		 * See RFC1323 for an explanation of the limit to 14
 		 */
-		space = max_t(u32, sysctl_tcp_rmem[2], sysctl_rmem_max);
+		space = max_t(u32, space, sysctl_tcp_rmem[2]);
+		space = max_t(u32, space, sysctl_rmem_max);
 		space = min_t(u32, space, *window_clamp);
 		while (space > 65535 && (*rcv_wscale) < 14) {
 			space >>= 1;

[PATCH 3.14 28/29] [PATCH 1/8] tcp: make challenge acks less predictable

[Greg Kroah-Hartman]

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

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

[ Upstream commit 75ff39ccc1bd5d3c455b6822ab09e533c551f758 ]

Yue Cao claims that current host rate limiting of challenge ACKS
(RFC 5961) could leak enough information to allow a patient attacker
to hijack TCP sessions. He will soon provide details in an academic
paper.

This patch increases the default limit from 100 to 1000, and adds
some randomization so that the attacker can no longer hijack
sessions without spending a considerable amount of probes.

Based on initial analysis and patch from Linus.

Note that we also have per socket rate limiting, so it is tempting
to remove the host limit in the future.

v2: randomize the count of challenge acks per second, not the period.

Fixes: 282f23c6ee34 ("tcp: implement RFC 5961 3.2")
Reported-by: Yue Cao <ycao009@ucr.edu>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/ipv4/tcp_input.c |   12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -87,7 +87,7 @@ int sysctl_tcp_adv_win_scale __read_most
 EXPORT_SYMBOL(sysctl_tcp_adv_win_scale);
 
 /* rfc5961 challenge ack rate limiting */
-int sysctl_tcp_challenge_ack_limit = 100;
+int sysctl_tcp_challenge_ack_limit = 1000;
 
 int sysctl_tcp_stdurg __read_mostly;
 int sysctl_tcp_rfc1337 __read_mostly;
@@ -3293,12 +3293,18 @@ static void tcp_send_challenge_ack(struc
 	static u32 challenge_timestamp;
 	static unsigned int challenge_count;
 	u32 now = jiffies / HZ;
+	u32 count;
 
 	if (now != challenge_timestamp) {
+		u32 half = (sysctl_tcp_challenge_ack_limit + 1) >> 1;
+
 		challenge_timestamp = now;
-		challenge_count = 0;
+		challenge_count = half +
+				  prandom_u32_max(sysctl_tcp_challenge_ack_limit);
 	}
-	if (++challenge_count <= sysctl_tcp_challenge_ack_limit) {
+	count = challenge_count;
+	if (count > 0) {
+		challenge_count = count - 1;
 		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPCHALLENGEACK);
 		tcp_send_ack(sk);
 	}

[PATCH 3.14 29/29] ext4: fix reference counting bug on block allocation error

[Greg Kroah-Hartman]

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

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

From: Vegard Nossum <vegard.nossum@oracle.com>

commit 554a5ccc4e4a20c5f3ec859de0842db4b4b9c77e upstream.

If we hit this error when mounted with errors=continue or
errors=remount-ro:

    EXT4-fs error (device loop0): ext4_mb_mark_diskspace_used:2940: comm ext4.exe: Allocating blocks 5090-6081 which overlap fs metadata

then ext4_mb_new_blocks() will call ext4_mb_release_context() and try to
continue. However, ext4_mb_release_context() is the wrong thing to call
here since we are still actually using the allocation context.

Instead, just error out. We could retry the allocation, but there is a
possibility of getting stuck in an infinite loop instead, so this seems
safer.

[ Fixed up so we don't return EAGAIN to userspace. --tytso ]

Fixes: 8556e8f3b6 ("ext4: Don't allow new groups to be added during block allocation")
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/ext4/mballoc.c |   17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2897,7 +2897,7 @@ ext4_mb_mark_diskspace_used(struct ext4_
 		ext4_error(sb, "Allocating blocks %llu-%llu which overlap "
 			   "fs metadata", block, block+len);
 		/* File system mounted not to panic on error
-		 * Fix the bitmap and repeat the block allocation
+		 * Fix the bitmap and return EUCLEAN
 		 * We leak some of the blocks here.
 		 */
 		ext4_lock_group(sb, ac->ac_b_ex.fe_group);
@@ -2906,7 +2906,7 @@ ext4_mb_mark_diskspace_used(struct ext4_
 		ext4_unlock_group(sb, ac->ac_b_ex.fe_group);
 		err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
 		if (!err)
-			err = -EAGAIN;
+			err = -EUCLEAN;
 		goto out_err;
 	}
 
@@ -4476,18 +4476,7 @@ repeat:
 	}
 	if (likely(ac->ac_status == AC_STATUS_FOUND)) {
 		*errp = ext4_mb_mark_diskspace_used(ac, handle, reserv_clstrs);
-		if (*errp == -EAGAIN) {
-			/*
-			 * drop the reference that we took
-			 * in ext4_mb_use_best_found
-			 */
-			ext4_mb_release_context(ac);
-			ac->ac_b_ex.fe_group = 0;
-			ac->ac_b_ex.fe_start = 0;
-			ac->ac_b_ex.fe_len = 0;
-			ac->ac_status = AC_STATUS_CONTINUE;
-			goto repeat;
-		} else if (*errp) {
+		if (*errp) {
 			ext4_discard_allocated_blocks(ac);
 			goto errout;
 		} else {

Re: [PATCH 3.14 00/29] 3.14.76-stable review

[Guenter Roeck]

On 08/14/2016 01:07 PM, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 3.14.76 release.
> There are 29 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 Tue Aug 16 20:07:18 UTC 2016.
> Anything received after that time might be too late.
>

Build results:
	total: 131 pass: 131 fail: 0
Qemu test results:
	total: 89 pass: 89 fail: 0

Details are available at http://kerneltests.org/builders.

Guenter

Re: [PATCH 3.14 00/29] 3.14.76-stable review

[Shuah Khan]

On 08/14/2016 02:07 PM, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 3.14.76 release.
> There are 29 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 Tue Aug 16 20:07:18 UTC 2016.
> 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.x/stable-review/patch-3.14.76-rc1.gz
> or in the git tree and branch at:
>   git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-3.14.y
> and the diffstat can be found below.
> 

Compiled and booted on my test system. No dmesg regressions.

thanks,
-- Shuah


-- 
Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America(Silicon Valley)
shuah.kh@samsung.com