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add CFI flags in mi8937_defconfig #2

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@codeReie codeReie commented Mar 7, 2022

kernel tree already has CFI commits same as:
CFI commit in Mido
Google's CFI for Clang commit
hence added CFI flags in default disabled mode

kernel tree already has CFI commits same as:
[CFI commit in Mido](ping2109/kernel_xiaomi_mido@00a195e)
[Google's CFI for Clang commit](https://android.googlesource.com/kernel/msm/+/4ca69fba291799969e4330178379e2ce97ba84dc%5E%21/)
hence added CFI flags in default disabled mode
me-cafebabe pushed a commit that referenced this pull request Jun 13, 2022
commit d1dc87763f406d4e67caf16dbe438a5647692395 upstream.

A rare BUG_ON triggered in assoc_array_gc:

    [3430308.818153] kernel BUG at lib/assoc_array.c:1609!

Which corresponded to the statement currently at line 1593 upstream:

    BUG_ON(assoc_array_ptr_is_meta(p));

Using the data from the core dump, I was able to generate a userspace
reproducer[1] and determine the cause of the bug.

[1]: https://github.com/brenns10/kernel_stuff/tree/master/assoc_array_gc

After running the iterator on the entire branch, an internal tree node
looked like the following:

    NODE (nr_leaves_on_branch: 3)
      SLOT [0] NODE (2 leaves)
      SLOT [1] NODE (1 leaf)
      SLOT [2..f] NODE (empty)

In the userspace reproducer, the pr_devel output when compressing this
node was:

    -- compress node 0x5607cc089380 --
    free=0, leaves=0
    [0] retain node 2/1 [nx 0]
    [1] fold node 1/1 [nx 0]
    [2] fold node 0/1 [nx 2]
    [3] fold node 0/2 [nx 2]
    [4] fold node 0/3 [nx 2]
    [5] fold node 0/4 [nx 2]
    [6] fold node 0/5 [nx 2]
    [7] fold node 0/6 [nx 2]
    [8] fold node 0/7 [nx 2]
    [9] fold node 0/8 [nx 2]
    [10] fold node 0/9 [nx 2]
    [11] fold node 0/10 [nx 2]
    [12] fold node 0/11 [nx 2]
    [13] fold node 0/12 [nx 2]
    [14] fold node 0/13 [nx 2]
    [15] fold node 0/14 [nx 2]
    after: 3

At slot 0, an internal node with 2 leaves could not be folded into the
node, because there was only one available slot (slot 0). Thus, the
internal node was retained. At slot 1, the node had one leaf, and was
able to be folded in successfully. The remaining nodes had no leaves,
and so were removed. By the end of the compression stage, there were 14
free slots, and only 3 leaf nodes. The tree was ascended and then its
parent node was compressed. When this node was seen, it could not be
folded, due to the internal node it contained.

The invariant for compression in this function is: whenever
nr_leaves_on_branch < ASSOC_ARRAY_FAN_OUT, the node should contain all
leaf nodes. The compression step currently cannot guarantee this, given
the corner case shown above.

To fix this issue, retry compression whenever we have retained a node,
and yet nr_leaves_on_branch < ASSOC_ARRAY_FAN_OUT. This second
compression will then allow the node in slot 1 to be folded in,
satisfying the invariant. Below is the output of the reproducer once the
fix is applied:

    -- compress node 0x560e9c562380 --
    free=0, leaves=0
    [0] retain node 2/1 [nx 0]
    [1] fold node 1/1 [nx 0]
    [2] fold node 0/1 [nx 2]
    [3] fold node 0/2 [nx 2]
    [4] fold node 0/3 [nx 2]
    [5] fold node 0/4 [nx 2]
    [6] fold node 0/5 [nx 2]
    [7] fold node 0/6 [nx 2]
    [8] fold node 0/7 [nx 2]
    [9] fold node 0/8 [nx 2]
    [10] fold node 0/9 [nx 2]
    [11] fold node 0/10 [nx 2]
    [12] fold node 0/11 [nx 2]
    [13] fold node 0/12 [nx 2]
    [14] fold node 0/13 [nx 2]
    [15] fold node 0/14 [nx 2]
    internal nodes remain despite enough space, retrying
    -- compress node 0x560e9c562380 --
    free=14, leaves=1
    [0] fold node 2/15 [nx 0]
    after: 3

Changes
=======
DH:
 - Use false instead of 0.
 - Reorder the inserted lines in a couple of places to put retained before
   next_slot.

ver #2)
 - Fix typo in pr_devel, correct comparison to "<="

Fixes: 3cb9895 ("Add a generic associative array implementation.")
Cc: <[email protected]>
Signed-off-by: Stephen Brennan <[email protected]>
Signed-off-by: David Howells <[email protected]>
cc: Andrew Morton <[email protected]>
cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]/ # v1
Link: https://lore.kernel.org/r/[email protected]/ # v2
Reviewed-by: Jarkko Sakkinen <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Jun 23, 2022
[ Upstream commit 6b9dbedbe3499fef862c4dff5217cf91f34e43b3 ]

pty_write() invokes kmalloc() which may invoke a normal printk() to print
failure message.  This can cause a deadlock in the scenario reported by
syz-bot below:

       CPU0              CPU1                    CPU2
       ----              ----                    ----
                         lock(console_owner);
                                                 lock(&port_lock_key);
  lock(&port->lock);
                         lock(&port_lock_key);
                                                 lock(&port->lock);
  lock(console_owner);

As commit dbdda842fe96 ("printk: Add console owner and waiter logic to
load balance console writes") said, such deadlock can be prevented by
using printk_deferred() in kmalloc() (which is invoked in the section
guarded by the port->lock).  But there are too many printk() on the
kmalloc() path, and kmalloc() can be called from anywhere, so changing
printk() to printk_deferred() is too complicated and inelegant.

Therefore, this patch chooses to specify __GFP_NOWARN to kmalloc(), so
that printk() will not be called, and this deadlock problem can be
avoided.

Syzbot reported the following lockdep error:

======================================================
WARNING: possible circular locking dependency detected
5.4.143-00237-g08ccc19a-dirty #10 Not tainted
------------------------------------------------------
syz-executor.4/29420 is trying to acquire lock:
ffffffff8aedb2a0 (console_owner){....}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:1752 [inline]
ffffffff8aedb2a0 (console_owner){....}-{0:0}, at: vprintk_emit+0x2ca/0x470 kernel/printk/printk.c:2023

but task is already holding lock:
ffff8880119c9158 (&port->lock){-.-.}-{2:2}, at: pty_write+0xf4/0x1f0 drivers/tty/pty.c:120

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&port->lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x35/0x50 kernel/locking/spinlock.c:159
       tty_port_tty_get drivers/tty/tty_port.c:288 [inline]          		<-- lock(&port->lock);
       tty_port_default_wakeup+0x1d/0xb0 drivers/tty/tty_port.c:47
       serial8250_tx_chars+0x530/0xa80 drivers/tty/serial/8250/8250_port.c:1767
       serial8250_handle_irq.part.0+0x31f/0x3d0 drivers/tty/serial/8250/8250_port.c:1854
       serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1827 [inline] 	<-- lock(&port_lock_key);
       serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1870
       serial8250_interrupt+0xfd/0x200 drivers/tty/serial/8250/8250_core.c:126
       __handle_irq_event_percpu+0x109/0xa50 kernel/irq/handle.c:156
       [...]

-> #1 (&port_lock_key){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x35/0x50 kernel/locking/spinlock.c:159
       serial8250_console_write+0x184/0xa40 drivers/tty/serial/8250/8250_port.c:3198
										<-- lock(&port_lock_key);
       call_console_drivers kernel/printk/printk.c:1819 [inline]
       console_unlock+0x8cb/0xd00 kernel/printk/printk.c:2504
       vprintk_emit+0x1b5/0x470 kernel/printk/printk.c:2024			<-- lock(console_owner);
       vprintk_func+0x8d/0x250 kernel/printk/printk_safe.c:394
       printk+0xba/0xed kernel/printk/printk.c:2084
       register_console+0x8b3/0xc10 kernel/printk/printk.c:2829
       univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:681
       console_init+0x49d/0x6d3 kernel/printk/printk.c:2915
       start_kernel+0x5e9/0x879 init/main.c:713
       secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

-> #0 (console_owner){....}-{0:0}:
       [...]
       lock_acquire+0x127/0x340 kernel/locking/lockdep.c:4734
       console_trylock_spinning kernel/printk/printk.c:1773 [inline]		<-- lock(console_owner);
       vprintk_emit+0x307/0x470 kernel/printk/printk.c:2023
       vprintk_func+0x8d/0x250 kernel/printk/printk_safe.c:394
       printk+0xba/0xed kernel/printk/printk.c:2084
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail+0x67b/0x7c0 lib/fault-inject.c:144
       __should_failslab+0x152/0x1c0 mm/failslab.c:33
       should_failslab+0x5/0x10 mm/slab_common.c:1224
       slab_pre_alloc_hook mm/slab.h:468 [inline]
       slab_alloc_node mm/slub.c:2723 [inline]
       slab_alloc mm/slub.c:2807 [inline]
       __kmalloc+0x72/0x300 mm/slub.c:3871
       kmalloc include/linux/slab.h:582 [inline]
       tty_buffer_alloc+0x23f/0x2a0 drivers/tty/tty_buffer.c:175
       __tty_buffer_request_room+0x156/0x2a0 drivers/tty/tty_buffer.c:273
       tty_insert_flip_string_fixed_flag+0x93/0x250 drivers/tty/tty_buffer.c:318
       tty_insert_flip_string include/linux/tty_flip.h:37 [inline]
       pty_write+0x126/0x1f0 drivers/tty/pty.c:122				<-- lock(&port->lock);
       n_tty_write+0xa7a/0xfc0 drivers/tty/n_tty.c:2356
       do_tty_write drivers/tty/tty_io.c:961 [inline]
       tty_write+0x512/0x930 drivers/tty/tty_io.c:1045
       __vfs_write+0x76/0x100 fs/read_write.c:494
       [...]

other info that might help us debug this:

Chain exists of:
  console_owner --> &port_lock_key --> &port->lock

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: b6da31b2c07c ("tty: Fix data race in tty_insert_flip_string_fixed_flag")
Signed-off-by: Qi Zheng <[email protected]>
Acked-by: Jiri Slaby <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Cc: Akinobu Mita <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Jun 23, 2022
commit 863e0d81b6683c4cbc588ad831f560c90e494bef upstream.

When user_dlm_destroy_lock failed, it didn't clean up the flags it set
before exit.  For USER_LOCK_IN_TEARDOWN, if this function fails because of
lock is still in used, next time when unlink invokes this function, it
will return succeed, and then unlink will remove inode and dentry if lock
is not in used(file closed), but the dlm lock is still linked in dlm lock
resource, then when bast come in, it will trigger a panic due to
user-after-free.  See the following panic call trace.  To fix this,
USER_LOCK_IN_TEARDOWN should be reverted if fail.  And also error should
be returned if USER_LOCK_IN_TEARDOWN is set to let user know that unlink
fail.

For the case of ocfs2_dlm_unlock failure, besides USER_LOCK_IN_TEARDOWN,
USER_LOCK_BUSY is also required to be cleared.  Even though spin lock is
released in between, but USER_LOCK_IN_TEARDOWN is still set, for
USER_LOCK_BUSY, if before every place that waits on this flag,
USER_LOCK_IN_TEARDOWN is checked to bail out, that will make sure no flow
waits on the busy flag set by user_dlm_destroy_lock(), then we can
simplely revert USER_LOCK_BUSY when ocfs2_dlm_unlock fails.  Fix
user_dlm_cluster_lock() which is the only function not following this.

[  941.336392] (python,26174,16):dlmfs_unlink:562 ERROR: unlink
004fb0000060000b5a90b8c847b72e1, error -16 from destroy
[  989.757536] ------------[ cut here ]------------
[  989.757709] kernel BUG at fs/ocfs2/dlmfs/userdlm.c:173!
[  989.757876] invalid opcode: 0000 [#1] SMP
[  989.758027] Modules linked in: ksplice_2zhuk2jr_ib_ipoib_new(O)
ksplice_2zhuk2jr(O) mptctl mptbase xen_netback xen_blkback xen_gntalloc
xen_gntdev xen_evtchn cdc_ether usbnet mii ocfs2 jbd2 rpcsec_gss_krb5
auth_rpcgss nfsv4 nfsv3 nfs_acl nfs fscache lockd grace ocfs2_dlmfs
ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs bnx2fc
fcoe libfcoe libfc scsi_transport_fc sunrpc ipmi_devintf bridge stp llc
rds_rdma rds bonding ib_sdp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad
rdma_cm ib_cm iw_cm falcon_lsm_serviceable(PE) falcon_nf_netcontain(PE)
mlx4_vnic falcon_kal(E) falcon_lsm_pinned_13402(E) mlx4_ib ib_sa ib_mad
ib_core ib_addr xenfs xen_privcmd dm_multipath iTCO_wdt iTCO_vendor_support
pcspkr sb_edac edac_core i2c_i801 lpc_ich mfd_core ipmi_ssif i2c_core ipmi_si
ipmi_msghandler
[  989.760686]  ioatdma sg ext3 jbd mbcache sd_mod ahci libahci ixgbe dca ptp
pps_core vxlan udp_tunnel ip6_udp_tunnel megaraid_sas mlx4_core crc32c_intel
be2iscsi bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi ipv6 cxgb3 mdio
libiscsi_tcp qla4xxx iscsi_boot_sysfs libiscsi scsi_transport_iscsi wmi
dm_mirror dm_region_hash dm_log dm_mod [last unloaded:
ksplice_2zhuk2jr_ib_ipoib_old]
[  989.761987] CPU: 10 PID: 19102 Comm: dlm_thread Tainted: P           OE
4.1.12-124.57.1.el6uek.x86_64 #2
[  989.762290] Hardware name: Oracle Corporation ORACLE SERVER
X5-2/ASM,MOTHERBOARD,1U, BIOS 30350100 06/17/2021
[  989.762599] task: ffff880178af6200 ti: ffff88017f7c8000 task.ti:
ffff88017f7c8000
[  989.762848] RIP: e030:[<ffffffffc07d4316>]  [<ffffffffc07d4316>]
__user_dlm_queue_lockres.part.4+0x76/0x80 [ocfs2_dlmfs]
[  989.763185] RSP: e02b:ffff88017f7cbcb8  EFLAGS: 00010246
[  989.763353] RAX: 0000000000000000 RBX: ffff880174d48008 RCX:
0000000000000003
[  989.763565] RDX: 0000000000120012 RSI: 0000000000000003 RDI:
ffff880174d48170
[  989.763778] RBP: ffff88017f7cbcc8 R08: ffff88021f4293b0 R09:
0000000000000000
[  989.763991] R10: ffff880179c8c000 R11: 0000000000000003 R12:
ffff880174d48008
[  989.764204] R13: 0000000000000003 R14: ffff880179c8c000 R15:
ffff88021db7a000
[  989.764422] FS:  0000000000000000(0000) GS:ffff880247480000(0000)
knlGS:ffff880247480000
[  989.764685] CS:  e033 DS: 0000 ES: 0000 CR0: 0000000080050033
[  989.764865] CR2: ffff8000007f6800 CR3: 0000000001ae0000 CR4:
0000000000042660
[  989.765081] Stack:
[  989.765167]  0000000000000003 ffff880174d48040 ffff88017f7cbd18
ffffffffc07d455f
[  989.765442]  ffff88017f7cbd88 ffffffff816fb639 ffff88017f7cbd38
ffff8800361b5600
[  989.765717]  ffff88021db7a000 ffff88021f429380 0000000000000003
ffffffffc0453020
[  989.765991] Call Trace:
[  989.766093]  [<ffffffffc07d455f>] user_bast+0x5f/0xf0 [ocfs2_dlmfs]
[  989.766287]  [<ffffffff816fb639>] ? schedule_timeout+0x169/0x2d0
[  989.766475]  [<ffffffffc0453020>] ? o2dlm_lock_ast_wrapper+0x20/0x20
[ocfs2_stack_o2cb]
[  989.766738]  [<ffffffffc045303a>] o2dlm_blocking_ast_wrapper+0x1a/0x20
[ocfs2_stack_o2cb]
[  989.767010]  [<ffffffffc0864ec6>] dlm_do_local_bast+0x46/0xe0 [ocfs2_dlm]
[  989.767217]  [<ffffffffc084f5cc>] ? dlm_lockres_calc_usage+0x4c/0x60
[ocfs2_dlm]
[  989.767466]  [<ffffffffc08501f1>] dlm_thread+0xa31/0x1140 [ocfs2_dlm]
[  989.767662]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.767834]  [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[  989.768006]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.768178]  [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[  989.768349]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.768521]  [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[  989.768693]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.768893]  [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[  989.769067]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.769241]  [<ffffffff810ce4d0>] ? wait_woken+0x90/0x90
[  989.769411]  [<ffffffffc084f7c0>] ? dlm_kick_thread+0x80/0x80 [ocfs2_dlm]
[  989.769617]  [<ffffffff810a8bbb>] kthread+0xcb/0xf0
[  989.769774]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.769945]  [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[  989.770117]  [<ffffffff810a8af0>] ? kthread_create_on_node+0x180/0x180
[  989.770321]  [<ffffffff816fdaa1>] ret_from_fork+0x61/0x90
[  989.770492]  [<ffffffff810a8af0>] ? kthread_create_on_node+0x180/0x180
[  989.770689] Code: d0 00 00 00 f0 45 7d c0 bf 00 20 00 00 48 89 83 c0 00 00
00 48 89 83 c8 00 00 00 e8 55 c1 8c c0 83 4b 04 10 48 83 c4 08 5b 5d c3 <0f>
0b 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 55 41 54 53 48 83
[  989.771892] RIP  [<ffffffffc07d4316>]
__user_dlm_queue_lockres.part.4+0x76/0x80 [ocfs2_dlmfs]
[  989.772174]  RSP <ffff88017f7cbcb8>
[  989.772704] ---[ end trace ebd1e38cebcc93a8 ]---
[  989.772907] Kernel panic - not syncing: Fatal exception
[  989.773173] Kernel Offset: disabled

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Junxiao Bi <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Joseph Qi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Jun 23, 2022
commit 520778042ccca019f3ffa136dd0ca565c486cedd upstream.

Since 3e135cd ("netfilter: nft_dynset: dynamic stateful expression
instantiation"), it is possible to attach stateful expressions to set
elements.

cd5125d8f518 ("netfilter: nf_tables: split set destruction in deactivate
and destroy phase") introduces conditional destruction on the object to
accomodate transaction semantics.

nft_expr_init() calls expr->ops->init() first, then check for
NFT_STATEFUL_EXPR, this stills allows to initialize a non-stateful
lookup expressions which points to a set, which might lead to UAF since
the set is not properly detached from the set->binding for this case.
Anyway, this combination is non-sense from nf_tables perspective.

This patch fixes this problem by checking for NFT_STATEFUL_EXPR before
expr->ops->init() is called.

The reporter provides a KASAN splat and a poc reproducer (similar to
those autogenerated by syzbot to report use-after-free errors). It is
unknown to me if they are using syzbot or if they use similar automated
tool to locate the bug that they are reporting.

For the record, this is the KASAN splat.

[   85.431824] ==================================================================
[   85.432901] BUG: KASAN: use-after-free in nf_tables_bind_set+0x81b/0xa20
[   85.433825] Write of size 8 at addr ffff8880286f0e98 by task poc/776
[   85.434756]
[   85.434999] CPU: 1 PID: 776 Comm: poc Tainted: G        W         5.18.0+ #2
[   85.436023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014

Fixes: 0b2d8a7 ("netfilter: nf_tables: add helper functions for expression handling")
Reported-and-tested-by: Aaron Adams <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
[Ajay: Regenerated the patch for v4.9.y]
Signed-off-by: Ajay Kaher <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Jul 7, 2022
[ Upstream commit 1b710b1b10eff9d46666064ea25f079f70bc67a8 ]

Sergey didn't like the locking order,

uart_port->lock  ->  tty_port->lock

uart_write (uart_port->lock)
  __uart_start
    pl011_start_tx
      pl011_tx_chars
        uart_write_wakeup
          tty_port_tty_wakeup
            tty_port_default
              tty_port_tty_get (tty_port->lock)

but those code is so old, and I have no clue how to de-couple it after
checking other locks in the splat. There is an onging effort to make all
printk() as deferred, so until that happens, workaround it for now as a
short-term fix.

LTP: starting iogen01 (export LTPROOT; rwtest -N iogen01 -i 120s -s
read,write -Da -Dv -n 2 500b:$TMPDIR/doio.f1.$$
1000b:$TMPDIR/doio.f2.$$)
WARNING: possible circular locking dependency detected
------------------------------------------------------
doio/49441 is trying to acquire lock:
ffff008b7cff7290 (&(&zone->lock)->rlock){..-.}, at: rmqueue+0x138/0x2050

but task is already holding lock:
60ff000822352818 (&pool->lock/1){-.-.}, at: start_flush_work+0xd8/0x3f0

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #4 (&pool->lock/1){-.-.}:
       lock_acquire+0x320/0x360
       _raw_spin_lock+0x64/0x80
       __queue_work+0x4b4/0xa10
       queue_work_on+0xac/0x11c
       tty_schedule_flip+0x84/0xbc
       tty_flip_buffer_push+0x1c/0x28
       pty_write+0x98/0xd0
       n_tty_write+0x450/0x60c
       tty_write+0x338/0x474
       __vfs_write+0x88/0x214
       vfs_write+0x12c/0x1a4
       redirected_tty_write+0x90/0xdc
       do_loop_readv_writev+0x140/0x180
       do_iter_write+0xe0/0x10c
       vfs_writev+0x134/0x1cc
       do_writev+0xbc/0x130
       __arm64_sys_writev+0x58/0x8c
       el0_svc_handler+0x170/0x240
       el0_sync_handler+0x150/0x250
       el0_sync+0x164/0x180

  -> #3 (&(&port->lock)->rlock){-.-.}:
       lock_acquire+0x320/0x360
       _raw_spin_lock_irqsave+0x7c/0x9c
       tty_port_tty_get+0x24/0x60
       tty_port_default_wakeup+0x1c/0x3c
       tty_port_tty_wakeup+0x34/0x40
       uart_write_wakeup+0x28/0x44
       pl011_tx_chars+0x1b8/0x270
       pl011_start_tx+0x24/0x70
       __uart_start+0x5c/0x68
       uart_write+0x164/0x1c8
       do_output_char+0x33c/0x348
       n_tty_write+0x4bc/0x60c
       tty_write+0x338/0x474
       redirected_tty_write+0xc0/0xdc
       do_loop_readv_writev+0x140/0x180
       do_iter_write+0xe0/0x10c
       vfs_writev+0x134/0x1cc
       do_writev+0xbc/0x130
       __arm64_sys_writev+0x58/0x8c
       el0_svc_handler+0x170/0x240
       el0_sync_handler+0x150/0x250
       el0_sync+0x164/0x180

  -> #2 (&port_lock_key){-.-.}:
       lock_acquire+0x320/0x360
       _raw_spin_lock+0x64/0x80
       pl011_console_write+0xec/0x2cc
       console_unlock+0x794/0x96c
       vprintk_emit+0x260/0x31c
       vprintk_default+0x54/0x7c
       vprintk_func+0x218/0x254
       printk+0x7c/0xa4
       register_console+0x734/0x7b0
       uart_add_one_port+0x734/0x834
       pl011_register_port+0x6c/0xac
       sbsa_uart_probe+0x234/0x2ec
       platform_drv_probe+0xd4/0x124
       really_probe+0x250/0x71c
       driver_probe_device+0xb4/0x200
       __device_attach_driver+0xd8/0x188
       bus_for_each_drv+0xbc/0x110
       __device_attach+0x120/0x220
       device_initial_probe+0x20/0x2c
       bus_probe_device+0x54/0x100
       device_add+0xae8/0xc2c
       platform_device_add+0x278/0x3b8
       platform_device_register_full+0x238/0x2ac
       acpi_create_platform_device+0x2dc/0x3a8
       acpi_bus_attach+0x390/0x3cc
       acpi_bus_attach+0x108/0x3cc
       acpi_bus_attach+0x108/0x3cc
       acpi_bus_attach+0x108/0x3cc
       acpi_bus_scan+0x7c/0xb0
       acpi_scan_init+0xe4/0x304
       acpi_init+0x100/0x114
       do_one_initcall+0x348/0x6a0
       do_initcall_level+0x190/0x1fc
       do_basic_setup+0x34/0x4c
       kernel_init_freeable+0x19c/0x260
       kernel_init+0x18/0x338
       ret_from_fork+0x10/0x18

  -> #1 (console_owner){-...}:
       lock_acquire+0x320/0x360
       console_lock_spinning_enable+0x6c/0x7c
       console_unlock+0x4f8/0x96c
       vprintk_emit+0x260/0x31c
       vprintk_default+0x54/0x7c
       vprintk_func+0x218/0x254
       printk+0x7c/0xa4
       get_random_u64+0x1c4/0x1dc
       shuffle_pick_tail+0x40/0xac
       __free_one_page+0x424/0x710
       free_one_page+0x70/0x120
       __free_pages_ok+0x61c/0xa94
       __free_pages_core+0x1bc/0x294
       memblock_free_pages+0x38/0x48
       __free_pages_memory+0xcc/0xfc
       __free_memory_core+0x70/0x78
       free_low_memory_core_early+0x148/0x18c
       memblock_free_all+0x18/0x54
       mem_init+0xb4/0x17c
       mm_init+0x14/0x38
       start_kernel+0x19c/0x530

  -> #0 (&(&zone->lock)->rlock){..-.}:
       validate_chain+0xf6c/0x2e2c
       __lock_acquire+0x868/0xc2c
       lock_acquire+0x320/0x360
       _raw_spin_lock+0x64/0x80
       rmqueue+0x138/0x2050
       get_page_from_freelist+0x474/0x688
       __alloc_pages_nodemask+0x3b4/0x18dc
       alloc_pages_current+0xd0/0xe0
       alloc_slab_page+0x2b4/0x5e0
       new_slab+0xc8/0x6bc
       ___slab_alloc+0x3b8/0x640
       kmem_cache_alloc+0x4b4/0x588
       __debug_object_init+0x778/0x8b4
       debug_object_init_on_stack+0x40/0x50
       start_flush_work+0x16c/0x3f0
       __flush_work+0xb8/0x124
       flush_work+0x20/0x30
       xlog_cil_force_lsn+0x88/0x204 [xfs]
       xfs_log_force_lsn+0x128/0x1b8 [xfs]
       xfs_file_fsync+0x3c4/0x488 [xfs]
       vfs_fsync_range+0xb0/0xd0
       generic_write_sync+0x80/0xa0 [xfs]
       xfs_file_buffered_aio_write+0x66c/0x6e4 [xfs]
       xfs_file_write_iter+0x1a0/0x218 [xfs]
       __vfs_write+0x1cc/0x214
       vfs_write+0x12c/0x1a4
       ksys_write+0xb0/0x120
       __arm64_sys_write+0x54/0x88
       el0_svc_handler+0x170/0x240
       el0_sync_handler+0x150/0x250
       el0_sync+0x164/0x180

       other info that might help us debug this:

 Chain exists of:
   &(&zone->lock)->rlock --> &(&port->lock)->rlock --> &pool->lock/1

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&pool->lock/1);
                               lock(&(&port->lock)->rlock);
                               lock(&pool->lock/1);
  lock(&(&zone->lock)->rlock);

                *** DEADLOCK ***

4 locks held by doio/49441:
 #0: a0ff00886fc27408 (sb_writers#8){.+.+}, at: vfs_write+0x118/0x1a4
 #1: 8fff00080810dfe0 (&xfs_nondir_ilock_class){++++}, at:
xfs_ilock+0x2a8/0x300 [xfs]
 #2: ffff9000129f2390 (rcu_read_lock){....}, at:
rcu_lock_acquire+0x8/0x38
 #3: 60ff000822352818 (&pool->lock/1){-.-.}, at:
start_flush_work+0xd8/0x3f0

               stack backtrace:
CPU: 48 PID: 49441 Comm: doio Tainted: G        W
Hardware name: HPE Apollo 70             /C01_APACHE_MB         , BIOS
L50_5.13_1.11 06/18/2019
Call trace:
 dump_backtrace+0x0/0x248
 show_stack+0x20/0x2c
 dump_stack+0xe8/0x150
 print_circular_bug+0x368/0x380
 check_noncircular+0x28c/0x294
 validate_chain+0xf6c/0x2e2c
 __lock_acquire+0x868/0xc2c
 lock_acquire+0x320/0x360
 _raw_spin_lock+0x64/0x80
 rmqueue+0x138/0x2050
 get_page_from_freelist+0x474/0x688
 __alloc_pages_nodemask+0x3b4/0x18dc
 alloc_pages_current+0xd0/0xe0
 alloc_slab_page+0x2b4/0x5e0
 new_slab+0xc8/0x6bc
 ___slab_alloc+0x3b8/0x640
 kmem_cache_alloc+0x4b4/0x588
 __debug_object_init+0x778/0x8b4
 debug_object_init_on_stack+0x40/0x50
 start_flush_work+0x16c/0x3f0
 __flush_work+0xb8/0x124
 flush_work+0x20/0x30
 xlog_cil_force_lsn+0x88/0x204 [xfs]
 xfs_log_force_lsn+0x128/0x1b8 [xfs]
 xfs_file_fsync+0x3c4/0x488 [xfs]
 vfs_fsync_range+0xb0/0xd0
 generic_write_sync+0x80/0xa0 [xfs]
 xfs_file_buffered_aio_write+0x66c/0x6e4 [xfs]
 xfs_file_write_iter+0x1a0/0x218 [xfs]
 __vfs_write+0x1cc/0x214
 vfs_write+0x12c/0x1a4
 ksys_write+0xb0/0x120
 __arm64_sys_write+0x54/0x88
 el0_svc_handler+0x170/0x240
 el0_sync_handler+0x150/0x250
 el0_sync+0x164/0x180

Reviewed-by: Sergey Senozhatsky <[email protected]>
Signed-off-by: Qian Cai <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Aug 1, 2022
In 2019, Sergey fixed a lockdep splat with 15341b1dd409 ("char/random:
silence a lockdep splat with printk()"), but that got reverted soon
after from 4.19 because back then it apparently caused various problems.
But the issue it was fixing is still there, and more generally, many
patches turning printk() into printk_deferred() have landed since,
making me suspect it's okay to try this out again.

This should fix the following deadlock found by the kernel test robot:

[   18.287691] WARNING: possible circular locking dependency detected
[   18.287692] 4.19.248-00165-g3d1f971aa81f #1 Not tainted
[   18.287693] ------------------------------------------------------
[   18.287712] stop/202 is trying to acquire lock:
[   18.287713] (ptrval) (console_owner){..-.}, at: console_unlock (??:?)
[   18.287717]
[   18.287718] but task is already holding lock:
[   18.287718] (ptrval) (&(&port->lock)->rlock){-...}, at: pty_write (pty.c:?)
[   18.287722]
[   18.287722] which lock already depends on the new lock.
[   18.287723]
[   18.287724]
[   18.287725] the existing dependency chain (in reverse order) is:
[   18.287725]
[   18.287726] -> #2 (&(&port->lock)->rlock){-...}:
[   18.287729] validate_chain+0x84a/0xe00
[   18.287729] __lock_acquire (lockdep.c:?)
[   18.287730] lock_acquire (??:?)
[   18.287731] _raw_spin_lock_irqsave (??:?)
[   18.287732] tty_port_tty_get (??:?)
[   18.287733] tty_port_default_wakeup (tty_port.c:?)
[   18.287734] tty_port_tty_wakeup (??:?)
[   18.287734] uart_write_wakeup (??:?)
[   18.287735] serial8250_tx_chars (??:?)
[   18.287736] serial8250_handle_irq (??:?)
[   18.287737] serial8250_default_handle_irq (8250_port.c:?)
[   18.287738] serial8250_interrupt (8250_core.c:?)
[   18.287738] __handle_irq_event_percpu (??:?)
[   18.287739] handle_irq_event_percpu (??:?)
[   18.287740] handle_irq_event (??:?)
[   18.287741] handle_edge_irq (??:?)
[   18.287742] handle_irq (??:?)
[   18.287742] do_IRQ (??:?)
[   18.287743] common_interrupt (entry_32.o:?)
[   18.287744] _raw_spin_unlock_irqrestore (??:?)
[   18.287745] uart_write (serial_core.c:?)
[   18.287746] process_output_block (n_tty.c:?)
[   18.287747] n_tty_write (n_tty.c:?)
[   18.287747] tty_write (tty_io.c:?)
[   18.287748] __vfs_write (??:?)
[   18.287749] vfs_write (??:?)
[   18.287750] ksys_write (??:?)
[   18.287750] sys_write (??:?)
[   18.287751] do_fast_syscall_32 (??:?)
[   18.287752] entry_SYSENTER_32 (??:?)
[   18.287752]
[   18.287753] -> #1 (&port_lock_key){-.-.}:
[   18.287756]
[   18.287756] -> #0 (console_owner){..-.}:
[   18.287759] check_prevs_add (lockdep.c:?)
[   18.287760] validate_chain+0x84a/0xe00
[   18.287761] __lock_acquire (lockdep.c:?)
[   18.287761] lock_acquire (??:?)
[   18.287762] console_unlock (??:?)
[   18.287763] vprintk_emit (??:?)
[   18.287764] vprintk_default (??:?)
[   18.287764] vprintk_func (??:?)
[   18.287765] printk (??:?)
[   18.287766] get_random_u32 (??:?)
[   18.287767] shuffle_freelist (slub.c:?)
[   18.287767] allocate_slab (slub.c:?)
[   18.287768] new_slab (slub.c:?)
[   18.287769] ___slab_alloc+0x6d0/0xb20
[   18.287770] __slab_alloc+0xd6/0x2e0
[   18.287770] __kmalloc (??:?)
[   18.287771] tty_buffer_alloc (tty_buffer.c:?)
[   18.287772] __tty_buffer_request_room (tty_buffer.c:?)
[   18.287773] tty_insert_flip_string_fixed_flag (??:?)
[   18.287774] pty_write (pty.c:?)
[   18.287775] process_output_block (n_tty.c:?)
[   18.287776] n_tty_write (n_tty.c:?)
[   18.287777] tty_write (tty_io.c:?)
[   18.287778] __vfs_write (??:?)
[   18.287779] vfs_write (??:?)
[   18.287780] ksys_write (??:?)
[   18.287780] sys_write (??:?)
[   18.287781] do_fast_syscall_32 (??:?)
[   18.287782] entry_SYSENTER_32 (??:?)
[   18.287783]
[   18.287783] other info that might help us debug this:
[   18.287784]
[   18.287785] Chain exists of:
[   18.287785]   console_owner --> &port_lock_key --> &(&port->lock)->rlock
[   18.287789]
[   18.287790]  Possible unsafe locking scenario:
[   18.287790]
[   18.287791]        CPU0                    CPU1
[   18.287792]        ----                    ----
[   18.287792]   lock(&(&port->lock)->rlock);
[   18.287794]                                lock(&port_lock_key);
[   18.287814]                                lock(&(&port->lock)->rlock);
[   18.287815]   lock(console_owner);
[   18.287817]
[   18.287818]  *** DEADLOCK ***
[   18.287818]
[   18.287819] 6 locks held by stop/202:
[   18.287820] #0: (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read (??:?)
[   18.287823] #1: (ptrval) (&tty->atomic_write_lock){+.+.}, at: tty_write_lock (tty_io.c:?)
[   18.287826] #2: (ptrval) (&o_tty->termios_rwsem/1){++++}, at: n_tty_write (n_tty.c:?)
[   18.287830] #3: (ptrval) (&ldata->output_lock){+.+.}, at: process_output_block (n_tty.c:?)
[   18.287834] #4: (ptrval) (&(&port->lock)->rlock){-...}, at: pty_write (pty.c:?)
[   18.287838] #5: (ptrval) (console_lock){+.+.}, at: console_trylock_spinning (printk.c:?)
[   18.287841]
[   18.287842] stack backtrace:
[   18.287843] CPU: 0 PID: 202 Comm: stop Not tainted 4.19.248-00165-g3d1f971aa81f #1
[   18.287843] Call Trace:
[   18.287844] dump_stack (??:?)
[   18.287845] print_circular_bug.cold+0x78/0x8b
[   18.287846] check_prev_add+0x66a/0xd20
[   18.287847] check_prevs_add (lockdep.c:?)
[   18.287848] validate_chain+0x84a/0xe00
[   18.287848] __lock_acquire (lockdep.c:?)
[   18.287849] lock_acquire (??:?)
[   18.287850] ? console_unlock (??:?)
[   18.287851] console_unlock (??:?)
[   18.287851] ? console_unlock (??:?)
[   18.287852] ? native_save_fl (??:?)
[   18.287853] vprintk_emit (??:?)
[   18.287854] vprintk_default (??:?)
[   18.287855] vprintk_func (??:?)
[   18.287855] printk (??:?)
[   18.287856] get_random_u32 (??:?)
[   18.287857] ? shuffle_freelist (slub.c:?)
[   18.287858] shuffle_freelist (slub.c:?)
[   18.287858] ? page_address (??:?)
[   18.287859] allocate_slab (slub.c:?)
[   18.287860] new_slab (slub.c:?)
[   18.287861] ? pvclock_clocksource_read (??:?)
[   18.287862] ___slab_alloc+0x6d0/0xb20
[   18.287862] ? kvm_sched_clock_read (kvmclock.c:?)
[   18.287863] ? __slab_alloc+0xbc/0x2e0
[   18.287864] ? native_wbinvd (paravirt.c:?)
[   18.287865] __slab_alloc+0xd6/0x2e0
[   18.287865] __kmalloc (??:?)
[   18.287866] ? __lock_acquire (lockdep.c:?)
[   18.287867] ? tty_buffer_alloc (tty_buffer.c:?)
[   18.287868] tty_buffer_alloc (tty_buffer.c:?)
[   18.287869] __tty_buffer_request_room (tty_buffer.c:?)
[   18.287869] tty_insert_flip_string_fixed_flag (??:?)
[   18.287870] pty_write (pty.c:?)
[   18.287871] process_output_block (n_tty.c:?)
[   18.287872] n_tty_write (n_tty.c:?)
[   18.287873] ? print_dl_stats (??:?)
[   18.287874] ? n_tty_ioctl (n_tty.c:?)
[   18.287874] tty_write (tty_io.c:?)
[   18.287875] ? n_tty_ioctl (n_tty.c:?)
[   18.287876] ? tty_write_unlock (tty_io.c:?)
[   18.287877] __vfs_write (??:?)
[   18.287877] vfs_write (??:?)
[   18.287878] ? __fget_light (file.c:?)
[   18.287879] ksys_write (??:?)

Cc: Sergey Senozhatsky <[email protected]>
Cc: Qian Cai <[email protected]>
Cc: Lech Perczak <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Theodore Ts'o <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: John Ogness <[email protected]>
Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/lkml/Ytz+lo4zRQYG3JUR@xsang-OptiPlex-9020
Signed-off-by: Jason A. Donenfeld <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Jan 10, 2023
[ Upstream commit f9574cd48679926e2a569e1957a5a1bcc8a719ac ]

Patch series "rapidio: fix three possible memory leaks".

This patchset fixes three name leaks in error handling.
 - patch #1 fixes two name leaks while rio_add_device() fails.
 - patch #2 fixes a name leak while  rio_register_mport() fails.

This patch (of 2):

If rio_add_device() returns error, the name allocated by dev_set_name()
need be freed.  It should use put_device() to give up the reference in the
error path, so that the name can be freed in kobject_cleanup(), and the
'rdev' can be freed in rio_release_dev().

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: e8de370 ("rapidio: add mport char device driver")
Fixes: 1fa5ae8 ("driver core: get rid of struct device's bus_id string array")
Signed-off-by: Yang Yingliang <[email protected]>
Cc: Alexandre Bounine <[email protected]>
Cc: Matt Porter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
me-cafebabe pushed a commit that referenced this pull request Jan 10, 2023
…g the sock

[ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ]

There is a race condition in vxlan that when deleting a vxlan device
during receiving packets, there is a possibility that the sock is
released after getting vxlan_sock vs from sk_user_data. Then in
later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got
NULL pointer dereference. e.g.

   #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757
   #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d
   #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48
   #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b
   #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb
   #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542
   #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62
      [exception RIP: vxlan_ecn_decapsulate+0x3b]
      RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246
      RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000
      RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700
      RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae
      R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700
      R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]
   #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507
   #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45
  #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807
  #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951
  #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde
  #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b
  #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139
  #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a
  #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3
  #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca
  #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3

Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh

Fix this by waiting for all sk_user_data reader to finish before
releasing the sock.

Reported-by: Jianlin Shi <[email protected]>
Suggested-by: Jakub Sitnicki <[email protected]>
Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs")
Signed-off-by: Hangbin Liu <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
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