The check based on index is not sufficient because

  IB_USER_VERBS_EX_CMD_CREATE_CQ = IB_USER_VERBS_CMD_CREATE_CQ

and IB_USER_VERBS_CMD_CREATE_CQ <= IB_USER_VERBS_CMD_OPEN_QP,
so if we execute IB_USER_VERBS_EX_CMD_CREATE_CQ this code checks
ib_dev->uverbs_cmd_mask not ib_dev->uverbs_ex_cmd_mask.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Move all command header processing into separate function
and perform those checks before acquiring SRCU read lock.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

The non-existing command is supposed to return -EOPNOTSUPP, but the
current code returns different errors for different flows for the
same failure. This patch unifies those flows.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Command that doesn't exist means that it is not supported,
so update code to return -EOPNOTSUPP in case of failure.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Fail as early as possible if not enough header data
was provided.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Since commit f21519b2 ("IB/core: extended command: an
improved infrastructure for uverbs commands"), the uverbs
supports extra flags as an input to the command interface.

However actually, there is only one flag available and used,
so it is better to refactor the code, so the resolution and
report to the users is done as early as possible.

As part of this change, we changed the return value of failure case
from ENOSYS to be EINVAL to be consistent with the rest flags checks.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Update sizeof() users to be consistent with coding style.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

The function validate_command_mask() returns only two results: success
or failure, so convert it to return bool instead of 0 and -1.
Reported-by: Noa Osherovich <noaos@mellanox.com>
Reviewed-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

There is a 14 patch series waiting to come into for-next that has a
dependecy on code submitted into this kernel's for-rc series.  So, merge
the for-rc branch into the current for-next in order to make the patch
series apply cleanly.
Signed-off-by: Doug Ledford <dledford@redhat.com>

Merge tag 'mlx5-updates-2018-02-21' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux into k.o/wip/dl-for-next

mlx5-updates-2018-02-21

This series includes shared code updates for mlx5 core driver for both
netdev and rdma subsystems.

By Saeed,
First six patches of the series are meant to address a performance issue
and should provide a performance boost for multi core IRQ interrupt hungry
workloads.  The issue is fixed in the first patch, all other patches are
meant to refactor the code in light of this fix.

The problem it comes to fix, is a shared spinlock accessed across all HCA
IRQs which protects the CQ database.  To solve this we simply move the CQ
database and its spinlock to be per EQ (IRQ), thus per core.

By Yonatan,
Fragmented completion queue (CQ) for RDMA,
core driver implementation to create fragmented CQ buffers rather than
one large contiguous memory buffer, the implementation scheme already
exist and used by the netdev CQs, the patch shares that code with the
rdma CQ creation flow and makes use of the new API in mlx5_ib driver.

Thanks,
Saeed.

Merged into rdma-next tree as well as net-next tree to prevent conflicts
in future patches between the two trees.
Signed-off-by: Doug Ledford <dledford@redhat.com>

Attempt to modify XRC_TGT QP type from the user space (ibv_xsrq_pingpong
invocation) will trigger the following kernel panic. It is caused by the
fact that such QPs missed uobject initialization.

[   17.408845] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[   17.412645] IP: rdma_lookup_put_uobject+0x9/0x50
[   17.416567] PGD 0 P4D 0
[   17.419262] Oops: 0000 [#1] SMP PTI
[   17.422915] CPU: 0 PID: 455 Comm: ibv_xsrq_pingpo Not tainted 4.16.0-rc1+ #86
[   17.424765] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[   17.427399] RIP: 0010:rdma_lookup_put_uobject+0x9/0x50
[   17.428445] RSP: 0018:ffffb8c7401e7c90 EFLAGS: 00010246
[   17.429543] RAX: 0000000000000000 RBX: ffffb8c7401e7cf8 RCX: 0000000000000000
[   17.432426] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
[   17.437448] RBP: 0000000000000000 R08: 00000000000218f0 R09: ffffffff8ebc4cac
[   17.440223] R10: fffff6038052cd80 R11: ffff967694b36400 R12: ffff96769391f800
[   17.442184] R13: ffffb8c7401e7cd8 R14: 0000000000000000 R15: ffff967699f60000
[   17.443971] FS:  00007fc29207d700(0000) GS:ffff96769fc00000(0000) knlGS:0000000000000000
[   17.446623] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   17.448059] CR2: 0000000000000048 CR3: 000000001397a000 CR4: 00000000000006b0
[   17.449677] Call Trace:
[   17.450247]  modify_qp.isra.20+0x219/0x2f0
[   17.451151]  ib_uverbs_modify_qp+0x90/0xe0
[   17.452126]  ib_uverbs_write+0x1d2/0x3c0
[   17.453897]  ? __handle_mm_fault+0x93c/0xe40
[   17.454938]  __vfs_write+0x36/0x180
[   17.455875]  vfs_write+0xad/0x1e0
[   17.456766]  SyS_write+0x52/0xc0
[   17.457632]  do_syscall_64+0x75/0x180
[   17.458631]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[   17.460004] RIP: 0033:0x7fc29198f5a0
[   17.460982] RSP: 002b:00007ffccc71f018 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   17.463043] RAX: ffffffffffffffda RBX: 0000000000000078 RCX: 00007fc29198f5a0
[   17.464581] RDX: 0000000000000078 RSI: 00007ffccc71f050 RDI: 0000000000000003
[   17.466148] RBP: 0000000000000000 R08: 0000000000000078 R09: 00007ffccc71f050
[   17.467750] R10: 000055b6cf87c248 R11: 0000000000000246 R12: 00007ffccc71f300
[   17.469541] R13: 000055b6cf8733a0 R14: 0000000000000000 R15: 0000000000000000
[   17.471151] Code: 00 00 0f 1f 44 00 00 48 8b 47 48 48 8b 00 48 8b 40 10 e9 0b 8b 68 00 90 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 53 89 f5 <48> 8b 47 48 48 89 fb 40 0f b6 f6 48 8b 00 48 8b 40 20 e8 e0 8a
[   17.475185] RIP: rdma_lookup_put_uobject+0x9/0x50 RSP: ffffb8c7401e7c90
[   17.476841] CR2: 0000000000000048
[   17.477764] ---[ end trace 1dbcc5354071a712 ]---
[   17.478880] Kernel panic - not syncing: Fatal exception
[   17.480277] Kernel Offset: 0xd000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)

Fixes: 2f08ee36 ("RDMA/restrack: don't use uaccess_kernel()")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

BNXT_RE_FLAG_TASK_IN_PROG doesn't handle multiple work
requests posted together. Track schedule of multiple
workqueue items by maintaining a per device counter
and proceed with IB dereg only if this counter is zero.
flush_workqueue is no longer required from
NETDEV_UNREGISTER path.
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

During driver unload, the driver proceeds with cleanup
without waiting for the scheduled events. So the device
pointers get freed up and driver crashes when the events
are scheduled later.

Flush the bnxt_re_task work queue before starting
device removal.
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Avoid system crash when destroy_qp is invoked while
the driver is processing the poll_cq. Synchronize these
functions using the cq_lock.
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Driver leaves the QP memory pinned if QP create command
fails from the FW. Avoids this scenario by adding a proper
exit path if the FW command fails.
Signed-off-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

More testing needs to be done before enabling this feature.
Disabling the feature temporarily
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

uaccess_kernel() isn't sufficient to determine if an rdma resource is
user-mode or not.  For example, resources allocated in the add_one()
function of an ib_client get falsely labeled as user mode, when they
are kernel mode allocations.  EG: mad qps.

The result is that these qps are skipped over during a nldev query
because of an erroneous namespace mismatch.

So now we determine if the resource is user-mode by looking at the object
struct's uobject or similar pointer to know if it was allocated for user
mode applications.

Fixes: 02d8883f ("RDMA/restrack: Add general infrastructure to track RDMA resources")
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Update all the flows to ensure that function pointer exists prior
to accessing it.

This is much safer than checking the uverbs_ex_mask variable, especially
since we know that test isn't working properly and will be removed
in -next.

This prevents a user triggereable oops.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Ensure that cv_end is equal to ibdev->num_comp_vectors for the
NUMA node with the highest index. This patch improves spreading
of RDMA channels over completion vectors and thereby improves
performance, especially on systems with only a single NUMA node.
This patch drops support for the comp_vector login parameter by
ignoring the value of that parameter since I have not found a
good way to combine support for that parameter and automatic
spreading of RDMA channels over completion vectors.

Fixes: d92c0da7 ("IB/srp: Add multichannel support")
Reported-by: Alexander Schmid <alex@modula-shop-systems.de>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Alexander Schmid <alex@modula-shop-systems.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This ensures that we return the right structures back to userspace.
Otherwise, it looks like the reserved fields in the response structures
in userspace might have uninitialized data in them.

Fixes: 8b10ba78 ("RDMA/vmw_pvrdma: Add shared receive queue support")
Fixes: 29c8d9eb ("IB: Add vmw_pvrdma driver")
Suggested-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Bryan Tan <bryantan@vmware.com>
Reviewed-by: Aditya Sarwade <asarwade@vmware.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Adit Ranadive <aditr@vmware.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

==================================================================
BUG: KASAN: use-after-free in copy_ah_attr_from_uverbs+0x6f2/0x8c0
Read of size 4 at addr ffff88006476a198 by task syzkaller697701/265

CPU: 0 PID: 265 Comm: syzkaller697701 Not tainted 4.15.0+ #90
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
Call Trace:
 dump_stack+0xde/0x164
 ? dma_virt_map_sg+0x22c/0x22c
 ? show_regs_print_info+0x17/0x17
 ? lock_contended+0x11a0/0x11a0
 print_address_description+0x83/0x3e0
 kasan_report+0x18c/0x4b0
 ? copy_ah_attr_from_uverbs+0x6f2/0x8c0
 ? copy_ah_attr_from_uverbs+0x6f2/0x8c0
 ? lookup_get_idr_uobject+0x120/0x200
 ? copy_ah_attr_from_uverbs+0x6f2/0x8c0
 copy_ah_attr_from_uverbs+0x6f2/0x8c0
 ? modify_qp+0xd0e/0x1350
 modify_qp+0xd0e/0x1350
 ib_uverbs_modify_qp+0xf9/0x170
 ? ib_uverbs_query_qp+0xa70/0xa70
 ib_uverbs_write+0x7f9/0xef0
 ? attach_entity_load_avg+0x8b0/0x8b0
 ? ib_uverbs_query_qp+0xa70/0xa70
 ? uverbs_devnode+0x110/0x110
 ? cyc2ns_read_end+0x10/0x10
 ? print_irqtrace_events+0x280/0x280
 ? sched_clock_cpu+0x18/0x200
 ? _raw_spin_unlock_irq+0x29/0x40
 ? _raw_spin_unlock_irq+0x29/0x40
 ? _raw_spin_unlock_irq+0x29/0x40
 ? time_hardirqs_on+0x27/0x670
 __vfs_write+0x10d/0x700
 ? uverbs_devnode+0x110/0x110
 ? kernel_read+0x170/0x170
 ? _raw_spin_unlock_irq+0x29/0x40
 ? finish_task_switch+0x1bd/0x7a0
 ? finish_task_switch+0x194/0x7a0
 ? prandom_u32_state+0xe/0x180
 ? rcu_read_unlock+0x80/0x80
 ? security_file_permission+0x93/0x260
 vfs_write+0x1b0/0x550
 SyS_write+0xc7/0x1a0
 ? SyS_read+0x1a0/0x1a0
 ? trace_hardirqs_on_thunk+0x1a/0x1c
 entry_SYSCALL_64_fastpath+0x1e/0x8b
RIP: 0033:0x433c29
RSP: 002b:00007ffcf2be82a8 EFLAGS: 00000217

Allocated by task 62:
 kasan_kmalloc+0xa0/0xd0
 kmem_cache_alloc+0x141/0x480
 dup_fd+0x101/0xcc0
 copy_process.part.62+0x166f/0x4390
 _do_fork+0x1cb/0xe90
 kernel_thread+0x34/0x40
 call_usermodehelper_exec_work+0x112/0x260
 process_one_work+0x929/0x1aa0
 worker_thread+0x5c6/0x12a0
 kthread+0x346/0x510
 ret_from_fork+0x3a/0x50

Freed by task 259:
 kasan_slab_free+0x71/0xc0
 kmem_cache_free+0xf3/0x4c0
 put_files_struct+0x225/0x2c0
 exit_files+0x88/0xc0
 do_exit+0x67c/0x1520
 do_group_exit+0xe8/0x380
 SyS_exit_group+0x1e/0x20
 entry_SYSCALL_64_fastpath+0x1e/0x8b

The buggy address belongs to the object at ffff88006476a000
 which belongs to the cache files_cache of size 832
The buggy address is located 408 bytes inside of
 832-byte region [ffff88006476a000, ffff88006476a340)
The buggy address belongs to the page:
page:ffffea000191da80 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
flags: 0x4000000000008100(slab|head)
raw: 4000000000008100 0000000000000000 0000000000000000 0000000100080008
raw: 0000000000000000 0000000100000001 ffff88006bcf7a80 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88006476a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88006476a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88006476a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88006476a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88006476a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Cc: syzkaller <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # 4.11
Fixes: 44c58487 ("IB/core: Define 'ib' and 'roce' rdma_ah_attr types")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Avoid circular locking dependency by calling
to uobj_alloc_commit() outside of xrcd_tree_mutex lock.

======================================================
WARNING: possible circular locking dependency detected
4.15.0+ #87 Not tainted
------------------------------------------------------
syzkaller401056/269 is trying to acquire lock:
 (&uverbs_dev->xrcd_tree_mutex){+.+.}, at: [<000000006c12d2cd>] uverbs_free_xrcd+0xd2/0x360

but task is already holding lock:
 (&ucontext->uobjects_lock){+.+.}, at: [<00000000da010f09>] uverbs_cleanup_ucontext+0x168/0x730

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&ucontext->uobjects_lock){+.+.}:
       __mutex_lock+0x111/0x1720
       rdma_alloc_commit_uobject+0x22c/0x600
       ib_uverbs_open_xrcd+0x61a/0xdd0
       ib_uverbs_write+0x7f9/0xef0
       __vfs_write+0x10d/0x700
       vfs_write+0x1b0/0x550
       SyS_write+0xc7/0x1a0
       entry_SYSCALL_64_fastpath+0x1e/0x8b

-> #0 (&uverbs_dev->xrcd_tree_mutex){+.+.}:
       lock_acquire+0x19d/0x440
       __mutex_lock+0x111/0x1720
       uverbs_free_xrcd+0xd2/0x360
       remove_commit_idr_uobject+0x6d/0x110
       uverbs_cleanup_ucontext+0x2f0/0x730
       ib_uverbs_cleanup_ucontext.constprop.3+0x52/0x120
       ib_uverbs_close+0xf2/0x570
       __fput+0x2cd/0x8d0
       task_work_run+0xec/0x1d0
       do_exit+0x6a1/0x1520
       do_group_exit+0xe8/0x380
       SyS_exit_group+0x1e/0x20
       entry_SYSCALL_64_fastpath+0x1e/0x8b

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ucontext->uobjects_lock);
                               lock(&uverbs_dev->xrcd_tree_mutex);
                               lock(&ucontext->uobjects_lock);
  lock(&uverbs_dev->xrcd_tree_mutex);

 *** DEADLOCK ***

3 locks held by syzkaller401056/269:
 #0:  (&file->cleanup_mutex){+.+.}, at: [<00000000c9f0c252>] ib_uverbs_close+0xac/0x570
 #1:  (&ucontext->cleanup_rwsem){++++}, at: [<00000000b6994d49>] uverbs_cleanup_ucontext+0xf6/0x730
 #2:  (&ucontext->uobjects_lock){+.+.}, at: [<00000000da010f09>] uverbs_cleanup_ucontext+0x168/0x730

stack backtrace:
CPU: 0 PID: 269 Comm: syzkaller401056 Not tainted 4.15.0+ #87
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
Call Trace:
 dump_stack+0xde/0x164
 ? dma_virt_map_sg+0x22c/0x22c
 ? uverbs_cleanup_ucontext+0x168/0x730
 ? console_unlock+0x502/0xbd0
 print_circular_bug.isra.24+0x35e/0x396
 ? print_circular_bug_header+0x12e/0x12e
 ? find_usage_backwards+0x30/0x30
 ? entry_SYSCALL_64_fastpath+0x1e/0x8b
 validate_chain.isra.28+0x25d1/0x40c0
 ? check_usage+0xb70/0xb70
 ? graph_lock+0x160/0x160
 ? find_usage_backwards+0x30/0x30
 ? cyc2ns_read_end+0x10/0x10
 ? print_irqtrace_events+0x280/0x280
 ? __lock_acquire+0x93d/0x1630
 __lock_acquire+0x93d/0x1630
 lock_acquire+0x19d/0x440
 ? uverbs_free_xrcd+0xd2/0x360
 __mutex_lock+0x111/0x1720
 ? uverbs_free_xrcd+0xd2/0x360
 ? uverbs_free_xrcd+0xd2/0x360
 ? __mutex_lock+0x828/0x1720
 ? mutex_lock_io_nested+0x1550/0x1550
 ? uverbs_cleanup_ucontext+0x168/0x730
 ? __lock_acquire+0x9a9/0x1630
 ? mutex_lock_io_nested+0x1550/0x1550
 ? uverbs_cleanup_ucontext+0xf6/0x730
 ? lock_contended+0x11a0/0x11a0
 ? uverbs_free_xrcd+0xd2/0x360
 uverbs_free_xrcd+0xd2/0x360
 remove_commit_idr_uobject+0x6d/0x110
 uverbs_cleanup_ucontext+0x2f0/0x730
 ? sched_clock_cpu+0x18/0x200
 ? uverbs_close_fd+0x1c0/0x1c0
 ib_uverbs_cleanup_ucontext.constprop.3+0x52/0x120
 ib_uverbs_close+0xf2/0x570
 ? ib_uverbs_remove_one+0xb50/0xb50
 ? ib_uverbs_remove_one+0xb50/0xb50
 __fput+0x2cd/0x8d0
 task_work_run+0xec/0x1d0
 do_exit+0x6a1/0x1520
 ? fsnotify_first_mark+0x220/0x220
 ? exit_notify+0x9f0/0x9f0
 ? entry_SYSCALL_64_fastpath+0x5/0x8b
 ? entry_SYSCALL_64_fastpath+0x5/0x8b
 ? trace_hardirqs_on_thunk+0x1a/0x1c
 ? time_hardirqs_on+0x27/0x670
 ? time_hardirqs_off+0x27/0x490
 ? syscall_return_slowpath+0x6c/0x460
 ? entry_SYSCALL_64_fastpath+0x5/0x8b
 do_group_exit+0xe8/0x380
 SyS_exit_group+0x1e/0x20
 entry_SYSCALL_64_fastpath+0x1e/0x8b
RIP: 0033:0x431ce9

Cc: syzkaller <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # 4.11
Fixes: fd3c7904 ("IB/core: Change idr objects to use the new schema")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

There is no matching lock for this mutex. Git history suggests this is
just a missed remnant from an earlier version of the function before
this locking was moved into uverbs_free_xrcd.

Originally this lock was protecting the xrcd_table_delete()

=====================================
WARNING: bad unlock balance detected!
4.15.0+ #87 Not tainted
-------------------------------------
syzkaller223405/269 is trying to release lock (&uverbs_dev->xrcd_tree_mutex) at:
[<00000000b8703372>] ib_uverbs_close_xrcd+0x195/0x1f0
but there are no more locks to release!

other info that might help us debug this:
1 lock held by syzkaller223405/269:
 #0:  (&uverbs_dev->disassociate_srcu){....}, at: [<000000005af3b960>] ib_uverbs_write+0x265/0xef0

stack backtrace:
CPU: 0 PID: 269 Comm: syzkaller223405 Not tainted 4.15.0+ #87
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
Call Trace:
 dump_stack+0xde/0x164
 ? dma_virt_map_sg+0x22c/0x22c
 ? ib_uverbs_write+0x265/0xef0
 ? console_unlock+0x502/0xbd0
 ? ib_uverbs_close_xrcd+0x195/0x1f0
 print_unlock_imbalance_bug+0x131/0x160
 lock_release+0x59d/0x1100
 ? ib_uverbs_close_xrcd+0x195/0x1f0
 ? lock_acquire+0x440/0x440
 ? lock_acquire+0x440/0x440
 __mutex_unlock_slowpath+0x88/0x670
 ? wait_for_completion+0x4c0/0x4c0
 ? rdma_lookup_get_uobject+0x145/0x2f0
 ib_uverbs_close_xrcd+0x195/0x1f0
 ? ib_uverbs_open_xrcd+0xdd0/0xdd0
 ib_uverbs_write+0x7f9/0xef0
 ? cyc2ns_read_end+0x10/0x10
 ? ib_uverbs_open_xrcd+0xdd0/0xdd0
 ? uverbs_devnode+0x110/0x110
 ? cyc2ns_read_end+0x10/0x10
 ? cyc2ns_read_end+0x10/0x10
 ? sched_clock_cpu+0x18/0x200
 __vfs_write+0x10d/0x700
 ? uverbs_devnode+0x110/0x110
 ? kernel_read+0x170/0x170
 ? __fget+0x358/0x5d0
 ? security_file_permission+0x93/0x260
 vfs_write+0x1b0/0x550
 SyS_write+0xc7/0x1a0
 ? SyS_read+0x1a0/0x1a0
 ? trace_hardirqs_on_thunk+0x1a/0x1c
 entry_SYSCALL_64_fastpath+0x1e/0x8b
RIP: 0033:0x4335c9

Cc: syzkaller <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # 4.11
Fixes: fd3c7904 ("IB/core: Change idr objects to use the new schema")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Once the uobj is committed it is immediately possible another thread
could destroy it, which worst case, can result in a use-after-free
of the restrack objects.

Cc: syzkaller <syzkaller@googlegroups.com>
Fixes: 08f294a1 ("RDMA/core: Add resource tracking for create and destroy CQs")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The command number is not bounds checked against the command mask before it
is shifted, resulting in an ubsan hit. This does not cause malfunction since
the command number is eventually bounds checked, but we can make this ubsan
clean by moving the bounds check to before the mask check.

================================================================================
UBSAN: Undefined behaviour in
drivers/infiniband/core/uverbs_main.c:647:21
shift exponent 207 is too large for 64-bit type 'long long unsigned int'
CPU: 0 PID: 446 Comm: syz-executor3 Not tainted 4.15.0-rc2+ #61
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
Call Trace:
dump_stack+0xde/0x164
? dma_virt_map_sg+0x22c/0x22c
ubsan_epilogue+0xe/0x81
__ubsan_handle_shift_out_of_bounds+0x293/0x2f7
? debug_check_no_locks_freed+0x340/0x340
? __ubsan_handle_load_invalid_value+0x19b/0x19b
? lock_acquire+0x440/0x440
? lock_acquire+0x19d/0x440
? __might_fault+0xf4/0x240
? ib_uverbs_write+0x68d/0xe20
ib_uverbs_write+0x68d/0xe20
? __lock_acquire+0xcf7/0x3940
? uverbs_devnode+0x110/0x110
? cyc2ns_read_end+0x10/0x10
? sched_clock_cpu+0x18/0x200
? sched_clock_cpu+0x18/0x200
__vfs_write+0x10d/0x700
? uverbs_devnode+0x110/0x110
? kernel_read+0x170/0x170
? __fget+0x35b/0x5d0
? security_file_permission+0x93/0x260
vfs_write+0x1b0/0x550
SyS_write+0xc7/0x1a0
? SyS_read+0x1a0/0x1a0
? trace_hardirqs_on_thunk+0x1a/0x1c
entry_SYSCALL_64_fastpath+0x18/0x85
RIP: 0033:0x448e29
RSP: 002b:00007f033f567c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f033f5686bc RCX: 0000000000448e29
RDX: 0000000000000060 RSI: 0000000020001000 RDI: 0000000000000012
RBP: 000000000070bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000056a0 R14: 00000000006e8740 R15: 0000000000000000
================================================================================

Cc: syzkaller <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # 4.5
Fixes: 2dbd5186 ("IB/core: IB/core: Allow legacy verbs through extended interfaces")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Reviewed-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

If remove_commit fails then the lock is left locked while the uobj still
exists. Eventually the kernel will deadlock.

lockdep detects this and says:

 test/4221 is leaving the kernel with locks still held!
 1 lock held by test/4221:
  #0:  (&ucontext->cleanup_rwsem){.+.+}, at: [<000000001e5c7523>] rdma_explicit_destroy+0x37/0x120 [ib_uverbs]

Fixes: 4da70da2 ("IB/core: Explicitly destroy an object while keeping uobject")
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This is really being used as an assert that the expected usecnt
is being held and implicitly that the usecnt is valid. Rename it to
assert_uverbs_usecnt and tighten the checks to only accept valid
values of usecnt (eg 0 and < -1 are invalid).

The tigher checkes make the assertion cover more cases and is more
likely to find bugs via syzkaller/etc.

Fixes: 38321256 ("IB/core: Add support for idr types")
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The race is between lookup_get_idr_uobject and
uverbs_idr_remove_uobj -> uverbs_uobject_put.

We deliberately do not call sychronize_rcu after the idr_remove in
uverbs_idr_remove_uobj for performance reasons, instead we call
kfree_rcu() during uverbs_uobject_put.

However, this means we can obtain pointers to uobj's that have
already been released and must protect against krefing them
using kref_get_unless_zero.

==================================================================
BUG: KASAN: use-after-free in copy_ah_attr_from_uverbs.isra.2+0x860/0xa00
Read of size 4 at addr ffff88005fda1ac8 by task syz-executor2/441

CPU: 1 PID: 441 Comm: syz-executor2 Not tainted 4.15.0-rc2+ #56
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
Call Trace:
dump_stack+0x8d/0xd4
print_address_description+0x73/0x290
kasan_report+0x25c/0x370
? copy_ah_attr_from_uverbs.isra.2+0x860/0xa00
copy_ah_attr_from_uverbs.isra.2+0x860/0xa00
? uverbs_try_lock_object+0x68/0xc0
? modify_qp.isra.7+0xdc4/0x10e0
modify_qp.isra.7+0xdc4/0x10e0
ib_uverbs_modify_qp+0xfe/0x170
? ib_uverbs_query_qp+0x970/0x970
? __lock_acquire+0xa11/0x1da0
ib_uverbs_write+0x55a/0xad0
? ib_uverbs_query_qp+0x970/0x970
? ib_uverbs_query_qp+0x970/0x970
? ib_uverbs_open+0x760/0x760
? futex_wake+0x147/0x410
? sched_clock_cpu+0x18/0x180
? check_prev_add+0x1680/0x1680
? do_futex+0x3b6/0xa30
? sched_clock_cpu+0x18/0x180
__vfs_write+0xf7/0x5c0
? ib_uverbs_open+0x760/0x760
? kernel_read+0x110/0x110
? lock_acquire+0x370/0x370
? __fget+0x264/0x3b0
vfs_write+0x18a/0x460
SyS_write+0xc7/0x1a0
? SyS_read+0x1a0/0x1a0
? trace_hardirqs_on_thunk+0x1a/0x1c
entry_SYSCALL_64_fastpath+0x18/0x85
RIP: 0033:0x448e29
RSP: 002b:00007f443fee0c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f443fee16bc RCX: 0000000000448e29
RDX: 0000000000000078 RSI: 00000000209f8000 RDI: 0000000000000012
RBP: 000000000070bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000008e98 R14: 00000000006ebf38 R15: 0000000000000000

Allocated by task 1:
kmem_cache_alloc_trace+0x16c/0x2f0
mlx5_alloc_cmd_msg+0x12e/0x670
cmd_exec+0x419/0x1810
mlx5_cmd_exec+0x40/0x70
mlx5_core_mad_ifc+0x187/0x220
mlx5_MAD_IFC+0xd7/0x1b0
mlx5_query_mad_ifc_gids+0x1f3/0x650
mlx5_ib_query_gid+0xa4/0xc0
ib_query_gid+0x152/0x1a0
ib_query_port+0x21e/0x290
mlx5_port_immutable+0x30f/0x490
ib_register_device+0x5dd/0x1130
mlx5_ib_add+0x3e7/0x700
mlx5_add_device+0x124/0x510
mlx5_register_interface+0x11f/0x1c0
mlx5_ib_init+0x56/0x61
do_one_initcall+0xa3/0x250
kernel_init_freeable+0x309/0x3b8
kernel_init+0x14/0x180
ret_from_fork+0x24/0x30

Freed by task 1:
kfree+0xeb/0x2f0
mlx5_free_cmd_msg+0xcd/0x140
cmd_exec+0xeba/0x1810
mlx5_cmd_exec+0x40/0x70
mlx5_core_mad_ifc+0x187/0x220
mlx5_MAD_IFC+0xd7/0x1b0
mlx5_query_mad_ifc_gids+0x1f3/0x650
mlx5_ib_query_gid+0xa4/0xc0
ib_query_gid+0x152/0x1a0
ib_query_port+0x21e/0x290
mlx5_port_immutable+0x30f/0x490
ib_register_device+0x5dd/0x1130
mlx5_ib_add+0x3e7/0x700
mlx5_add_device+0x124/0x510
mlx5_register_interface+0x11f/0x1c0
mlx5_ib_init+0x56/0x61
do_one_initcall+0xa3/0x250
kernel_init_freeable+0x309/0x3b8
kernel_init+0x14/0x180
ret_from_fork+0x24/0x30

The buggy address belongs to the object at ffff88005fda1ab0
which belongs to the cache kmalloc-32 of size 32
The buggy address is located 24 bytes inside of
32-byte region [ffff88005fda1ab0, ffff88005fda1ad0)
The buggy address belongs to the page:
page:00000000d5655c19 count:1 mapcount:0 mapping: (null)
index:0xffff88005fda1fc0
flags: 0x4000000000000100(slab)
raw: 4000000000000100 0000000000000000 ffff88005fda1fc0 0000000180550008
raw: ffffea00017f6780 0000000400000004 ffff88006c803980 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff88005fda1980: fc fc fb fb fb fb fc fc fb fb fb fb fc fc fb fb
ffff88005fda1a00: fb fb fc fc fb fb fb fb fc fc 00 00 00 00 fc fc
ffff88005fda1a80: fb fb fb fb fc fc fb fb fb fb fc fc fb fb fb fb
ffff88005fda1b00: fc fc 00 00 00 00 fc fc fb fb fb fb fc fc fb fb
ffff88005fda1b80: fb fb fc fc fb fb fb fb fc fc fb fb fb fb fc fc
==================================================================@

Cc: syzkaller <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # 4.11
Fixes: 38321256 ("IB/core: Add support for idr types")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This clarifies the design intention that time between allocate and
commit has the uobj exclusive to the caller. We already guarantee
this by delaying publishing the uobj pointer via idr_insert,
fd_install, list_add, etc.

Additionally holding the usecnt lock during this period provides
extra clarity and more protection against future mistakes.

Fixes: 38321256 ("IB/core: Add support for idr types")
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

If the same attribute is listed twice by the user in the ioctl attribute
list then error unwind can cause the kernel to deref garbage.

This happens when an object with WRITE access is sent twice. The second
parse properly fails but corrupts the state required for the error unwind
it triggers.

Fixing this by making duplicates in the attribute list invalid. This is
not something we need to support.

The ioctl interface is currently recommended to be disabled in kConfig.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

32 bit processes running on a 64 bit kernel call compat_ioctl so that
implementations can revise any structure layout issues. Point compat_ioctl
at our normal ioctl because:

- All our structures are designed to be the same on 32 and 64 bit, ie we
  use __aligned_u64 when required and are careful to manage padding.

- Any pointers are stored in u64's and userspace is expected
  to prepare them properly.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This has no impact on the structure layout since these structs already
have their u64s already properly aligned, but it does document that we
have this requirement for 32 bit compatibility.
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Fix a bug in uverbs_ioctl_merge that looked at the object's iterator
number instead of the method's iterator number when merging methods.

While we're at it, make the uverbs_ioctl_merge code a bit more clear
and faster.

Fixes: 118620d3 ('IB/core: Add uverbs merge trees functionality')
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The union approach will get the endianness wrong sometimes if the kernel's
pointer size is 32 bits resulting in EFAULTs when trying to copy to/from
user.
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The rule for the API is pointers less than 8 bytes are inlined into
the .data field of the attribute. Fix the creation of the driver udata
struct to follow this rule and point to the .data itself when the size
is less than 8 bytes.

Otherwise if the UHW struct is less than 8 bytes the driver will get
EFAULT during copy_from_user.
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

This fixes several bugs around the copy_to/from user path:
 - copy_to used the user provided size of the attribute
   and could copy data beyond the end of the kernel buffer into
   userspace.
 - copy_from didn't know the size of the kernel buffer and
   could have left kernel memory unexpectedly un-initialized.
 - copy_from did not use the user length to determine if the
   attribute data is inlined or not.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Resource tracking of XRCD objects is not implemented in current
version of restrack and hence can be removed.

Fixes: 02d8883f ("RDMA/restrack: Add general infrastructure to track RDMA resources")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

netdev_wait_allrefs() could rebroadcast NETDEV_UNREGISTER event
multiple times until all refs are gone, which will result in calling
ipoib_delete_debug_files multiple times and printing a warning.

Remove the WARN_ONCE since checks of NULL pointers before calling
debugfs_remove are not needed.

Fixes: 771a5258 ("IB/IPoIB: ibX: failed to create mcg debug file")
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The current implementation of create CQ requires contiguous
memory, such requirement is problematic once the memory is
fragmented or the system is low in memory, it causes for
failures in dma_zalloc_coherent().

This patch implements new scheme of fragmented CQ to overcome
this issue by introducing new type: 'struct mlx5_frag_buf_ctrl'
to allocate fragmented buffers, rather than contiguous ones.

Base the Completion Queues (CQs) on this new fragmented buffer.

It fixes following crashes:
kworker/29:0: page allocation failure: order:6, mode:0x80d0
CPU: 29 PID: 8374 Comm: kworker/29:0 Tainted: G OE 3.10.0
Workqueue: ib_cm cm_work_handler [ib_cm]
Call Trace:
[<>] dump_stack+0x19/0x1b
[<>] warn_alloc_failed+0x110/0x180
[<>] __alloc_pages_slowpath+0x6b7/0x725
[<>] __alloc_pages_nodemask+0x405/0x420
[<>] dma_generic_alloc_coherent+0x8f/0x140
[<>] x86_swiotlb_alloc_coherent+0x21/0x50
[<>] mlx5_dma_zalloc_coherent_node+0xad/0x110 [mlx5_core]
[<>] ? mlx5_db_alloc_node+0x69/0x1b0 [mlx5_core]
[<>] mlx5_buf_alloc_node+0x3e/0xa0 [mlx5_core]
[<>] mlx5_buf_alloc+0x14/0x20 [mlx5_core]
[<>] create_cq_kernel+0x90/0x1f0 [mlx5_ib]
[<>] mlx5_ib_create_cq+0x3b0/0x4e0 [mlx5_ib]
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

EQ structure and API is private to mlx5_core driver only, external
drivers should not have access or the means to manipulate EQ objects.

Remove redundant exports and move API functions out of the linux/mlx5
include directory into the driver's mlx5_core.h private include file.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Gal Pressman <galp@mellanox.com>