Move as much as possible to kernel space; leave the parts in user space
that rely on checking memory allocation failures to detect the
transition between an exceptional entry and a bitmap.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Convert to new API and move to kernel space.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Convert to new API and move to kernel space.  Take the opportunity to
test the situation a little more thoroughly (ie at different offsets).
Signed-off-by: Matthew Wilcox <willy@infradead.org>

We can't move this test to kernel space because there's no way to
force kmalloc to fail.  But we can use the new API and check this
works when the test is in userspace.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Start transitioning the IDA tests into kernel space.  Framework heavily
cribbed from test_xarray.c.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Since the session is never looked up by ID, we can use the more
space-efficient IDA instead of the IDR.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The problem is that iscsi_login_zero_tsih_s1 sets conn->sess early in
iscsi_login_set_conn_values. If the function fails later like when we
alloc the idr it does kfree(sess) and leaves the conn->sess pointer set.
iscsi_login_zero_tsih_s1 then returns -Exyz and we then call
iscsi_target_login_sess_out and access the freed memory.

This patch has iscsi_login_zero_tsih_s1 either completely setup the
session or completely tear it down, so later in
iscsi_target_login_sess_out we can just check for it being set to the
connection.

Cc: stable@vger.kernel.org
Fixes: 0957627a ("iscsi-target: Fix sess allocation leak in...")
Signed-off-by: Mike Christie <mchristi@redhat.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Reorder allocation to avoid an awkward lock/unlock/lock sequence.
Simpler code due to being able to use ida_alloc_max(), even if we can't
eliminate the driver's spinlock.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>

Simpler and shorter code.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Vinod Koul <vkoul@kernel.org>

Removes a custom spinlock and simplifies the code.  Also fix an
error where we could allocate one ID too many.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Removes a call to ida_pre_get().
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

ida_alloc_range is the perfect fit for this use case.  Eliminates
a custom spinlock, a call to ida_pre_get and a local check for the
allocated ID exceeding a maximum.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

Signed-off-by: Matthew Wilcox <willy@infradead.org>

Eliminates the custom spinlock and the call to ida_pre_get.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>

Eliminate the custom spinlock and the call to ida_pre_get.
Also add a call to ida_free() in the card remove routine, which I believe
fixes a bug in this driver.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Slightly simpler code.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Allows us to remove an explicit spinlock.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

ida_alloc_max() matches what this driver wants to do.  Also removes a
call to ida_pre_get().  We no longer need the protection of the mutex,
so convert pty_count to an atomic_t and remove the mutex entirely.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

We don't need to keep track of the starting value; the IDA is efficient.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The new API is much easier for this user.  Also add kerneldoc for
get_anon_bdev().
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Removes a use of ida_pre_get() and a personalised spinlock.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

Add ida_alloc(), ida_alloc_min(), ida_alloc_max(), ida_alloc_range()
and ida_free().  The ida_alloc_max() and ida_alloc_range() functions
differ from ida_simple_get() in that they take an inclusive 'max'
parameter instead of an exclusive 'end' parameter.  Callers are about
evenly split whether they'd like inclusive or exclusive parameters and
'max' is easier to document than 'end'.

Change the IDA allocation to first attempt to allocate a bit using
existing memory, and only allocate memory afterwards.  Also change the
behaviour of 'min' > INT_MAX from being a BUG() to returning -ENOSPC.

Leave compatibility wrappers in place for ida_simple_get() and
ida_simple_remove() to avoid changing all callers.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The user has no need to handle locking between ida_simple_get() and
ida_simple_remove().  They shouldn't be forced to think about whether
ida_destroy() might be called at the same time as any of their other
IDA manipulation calls.  Improve the documnetation while I'm in here.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

get_slot_offset() can be called with a NULL 'parent' argument.
In this case, the calculated value will not be used, but calculating
it is undefined.  Rather than fixing the caller (__radix_tree_delete)
to not call get_slot_offset(), make get_slot_offset() robust against
being called with a NULL parent.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Add support for the undefined behaviour sanitizer and fix the bugs
that ubsan pointed out.  Nothing major, and all in the test suite,
not the code.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

An include of xarray.h was added to lib/idr.c without updating the test
suite.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Pull SCSI fixes from James Bottomley:
 "Eight fixes.

  The most important one is the mpt3sas fix which makes the driver work
  again on big endian systems. The rest are mostly minor error path or
  checker issues and the vmw_scsi one fixes a performance problem"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: vmw_pvscsi: Return DID_RESET for status SAM_STAT_COMMAND_TERMINATED
  scsi: sr: Avoid that opening a CD-ROM hangs with runtime power management enabled
  scsi: mpt3sas: Swap I/O memory read value back to cpu endianness
  scsi: fcoe: clear FC_RP_STARTED flags when receiving a LOGO
  scsi: fcoe: drop frames in ELS LOGO error path
  scsi: fcoe: fix use-after-free in fcoe_ctlr_els_send
  scsi: qedi: Fix a potential buffer overflow
  scsi: qla2xxx: Fix memory leak for allocating abort IOCB

This is purely a preparatory patch for upcoming changes during the 4.19
merge window.

We have a function called "boot_cpu_state_init()" that isn't really
about the bootup cpu state: that is done much earlier by the similarly
named "boot_cpu_init()" (note lack of "state" in name).

This function initializes some hotplug CPU state, and needs to run after
the percpu data has been properly initialized.  It even has a comment to
that effect.

Except it _doesn't_ actually run after the percpu data has been properly
initialized.  On x86 it happens to do that, but on at least arm and
arm64, the percpu base pointers are initialized by the arch-specific
'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init().

This had some unexpected results, and in particular we have a patch
pending for the merge window that did the obvious cleanup of using
'this_cpu_write()' in the cpu hotplug init code:

  -       per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE;
  +       this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);

which is obviously the right thing to do.  Except because of the
ordering issue, it actually failed miserably and unexpectedly on arm64.

So this just fixes the ordering, and changes the name of the function to
be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu
hotplug state, because the core CPU state was supposed to have already
been done earlier.

Marked for stable, since the (not yet merged) patch that will show this
problem is marked for stable.
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull vfs fixes from Al Viro:
 "A bunch of race fixes, mostly around lazy pathwalk.

  All of it is -stable fodder, a large part going back to 2013"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  make sure that __dentry_kill() always invalidates d_seq, unhashed or not
  fix __legitimize_mnt()/mntput() race
  fix mntput/mntput race
  root dentries need RCU-delayed freeing

Pull networking fixes from David Miller:
 "Last bit of straggler fixes...

  1) Fix btf library licensing to LGPL, from Martin KaFai lau.

  2) Fix error handling in bpf sockmap code, from Daniel Borkmann.

  3) XDP cpumap teardown handling wrt. execution contexts, from Jesper
     Dangaard Brouer.

  4) Fix loss of runtime PM on failed vlan add/del, from Ivan
     Khoronzhuk.

  5) xen-netfront caches skb_shinfo(skb) across a __pskb_pull_tail()
     call, which potentially changes the skb's data buffer, and thus
     skb_shinfo(). Fix from Juergen Gross"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  xen/netfront: don't cache skb_shinfo()
  net: ethernet: ti: cpsw: fix runtime_pm while add/kill vlan
  net: ethernet: ti: cpsw: clear all entries when delete vid
  xdp: fix bug in devmap teardown code path
  samples/bpf: xdp_redirect_cpu adjustment to reproduce teardown race easier
  xdp: fix bug in cpumap teardown code path
  bpf, sockmap: fix cork timeout for select due to epipe
  bpf, sockmap: fix leak in bpf_tcp_sendmsg wait for mem path
  bpf, sockmap: fix bpf_tcp_sendmsg sock error handling
  bpf: btf: Change tools/lib/bpf/btf to LGPL

skb_shinfo() can change when calling __pskb_pull_tail(): Don't cache
its return value.

Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Grygorii Strashko says:

====================
net: ethernet: ti: cpsw: fix runtime pm while add/del reserved vid

Here 2 not critical fixes for:
- vlan ale table leak while error if deleting vlan (simplifies next fix)
- runtime pm while try to set reserved vlan
====================
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It's exclusive with normal behaviour but if try to set vlan to one of
the reserved values is made, the cpsw runtime pm is broken.

Fixes: a6c5d14f ("drivers: net: cpsw: ndev: fix accessing to suspended device")
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

In cases if some of the entries were not found in forwarding table
while killing vlan, the rest not needed entries still left in the
table. No need to stop, as entry was deleted anyway. So fix this by
returning error only after all was cleaned. To implement this, return
-ENOENT in cpsw_ale_del_mcast() as it's supposed to be.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

If zram supports writeback feature, it's no longer a
BD_CAP_SYNCHRONOUS_IO device beause zram does asynchronous IO operations
for incompressible pages.

Do not pretend to be synchronous IO device.  It makes the system very
sluggish due to waiting for IO completion from upper layers.

Furthermore, it causes a user-after-free problem because swap thinks the
opearion is done when the IO functions returns so it can free the page
(e.g., lock_page_or_retry and goto out_release in do_swap_page) but in
fact, IO is asynchronous so the driver could access a just freed page
afterward.

This patch fixes the problem.

  BUG: Bad page state in process qemu-system-x86  pfn:3dfab21
  page:ffffdfb137eac840 count:0 mapcount:0 mapping:0000000000000000 index:0x1
  flags: 0x17fffc000000008(uptodate)
  raw: 017fffc000000008 dead000000000100 dead000000000200 0000000000000000
  raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
  page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
  bad because of flags: 0x8(uptodate)
  CPU: 4 PID: 1039 Comm: qemu-system-x86 Tainted: G    B 4.18.0-rc5+ #1
  Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0b 05/02/2017
  Call Trace:
    dump_stack+0x5c/0x7b
    bad_page+0xba/0x120
    get_page_from_freelist+0x1016/0x1250
    __alloc_pages_nodemask+0xfa/0x250
    alloc_pages_vma+0x7c/0x1c0
    do_swap_page+0x347/0x920
    __handle_mm_fault+0x7b4/0x1110
    handle_mm_fault+0xfc/0x1f0
    __get_user_pages+0x12f/0x690
    get_user_pages_unlocked+0x148/0x1f0
    __gfn_to_pfn_memslot+0xff/0x3c0 [kvm]
    try_async_pf+0x87/0x230 [kvm]
    tdp_page_fault+0x132/0x290 [kvm]
    kvm_mmu_page_fault+0x74/0x570 [kvm]
    kvm_arch_vcpu_ioctl_run+0x9b3/0x1990 [kvm]
    kvm_vcpu_ioctl+0x388/0x5d0 [kvm]
    do_vfs_ioctl+0xa2/0x630
    ksys_ioctl+0x70/0x80
    __x64_sys_ioctl+0x16/0x20
    do_syscall_64+0x55/0x100
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
[minchan@kernel.org: fix changelog, add comment]
 Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
 Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
 Link: http://lkml.kernel.org/r/20180805233722.217347-1-minchan@kernel.org
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Tino Lehnig <tino.lehnig@contabo.de>
Tested-by: Tino Lehnig <tino.lehnig@contabo.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>	[4.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ioremap_prot() can return NULL which could lead to an oops.

Link: http://lkml.kernel.org/r/1533195441-58594-1-git-send-email-chenjie6@huawei.comSigned-off-by: chen jie <chenjie6@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: chenjie <chenjie6@huawei.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With gcc-8 fsanitize=null become very noisy.  GCC started to complain
about things like &a->b, where 'a' is NULL pointer.  There is no NULL
dereference, we just calculate address to struct member.  It's
technically undefined behavior so UBSAN is correct to report it.  But as
long as there is no real NULL-dereference, I think, we should be fine.

-fno-delete-null-pointer-checks compiler flag should protect us from any
consequences.  So let's just no use -fsanitize=null as it's not useful
for us.  If there is a real NULL-deref we will see crash.  Even if
userspace mapped something at NULL (root can do this), with things like
SMAP should catch the issue.

Link: http://lkml.kernel.org/r/20180802153209.813-1-aryabinin@virtuozzo.comSigned-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This entry was created with my personal e-mail address.  Update this entry
to my open-source kernel.org account.

Link: http://lkml.kernel.org/r/20180806143904.4716-4-kieran.bingham@ideasonboard.comSigned-off-by: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull i2c fix from Wolfram Sang:
 "A single driver bugfix for I2C.

  The bug was found by systematically stress testing the driver, so I am
  confident to merge it that late in the cycle although it is probably
  unusually large"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: xlp9xx: Fix case where SSIF read transaction completes early