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fbcon and mali seem to cause crash if both loaded #56

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TJC opened this issue Jul 19, 2012 · 4 comments
Closed

fbcon and mali seem to cause crash if both loaded #56

TJC opened this issue Jul 19, 2012 · 4 comments

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@TJC
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TJC commented Jul 19, 2012

I'm currently at commit 23e5456 in the allwinner-v3.0-android-v2 branch.

If I attempt to load the various Mali display modules, as well as fbcon for the console, then the modprobe on fbcon hangs for a long time, then my device crashes.

Apologies for the brevity of this error report -- I do not have a current way to capture any kernel panics as my device is headless and had not written it to syslog.

Note that everything was being loaded as modules, not compiled into kernel.

@amery
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amery commented Jul 19, 2012

unfortunatelly fbcon is not supported

@amery
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amery commented Jul 19, 2012

see #6

@amery amery closed this as completed Jul 19, 2012
@TJC
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TJC commented Jul 19, 2012

Ah, my apologies.

@hno
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hno commented Jul 19, 2012

ons 2012-07-18 klockan 22:09 -0700 skrev Toby Corkindale:

If I attempt to load the various Mali display modules, as well as fbcon for the console, then the modprobe on fbcon hangs for a long time, then my device crashes.

fbcon is known to be broken with the sunxi disp framebuffer driver. Not
related to mali.

Regards
Henrik

amery pushed a commit that referenced this issue Oct 17, 2013
When CMA fails to initialize in v3.12-rc4, the chipidea driver oopses
the kernel while trying to remove and put the HCD which doesn't exist:

WARNING: CPU: 0 PID: 6 at /home/rmk/git/linux-rmk/arch/arm/mm/dma-mapping.c:511
__dma_alloc+0x200/0x240()
coherent pool not initialised!
Modules linked in:
CPU: 0 PID: 6 Comm: kworker/u2:0 Tainted: G        W    3.12.0-rc4+ #56
Workqueue: deferwq deferred_probe_work_func
Backtrace:
[<c001218c>] (dump_backtrace+0x0/0x10c) from [<c0012328>] (show_stack+0x18/0x1c)
 r6:c05fd9cc r5:000001ff r4:00000000 r3:df86ad00
[<c0012310>] (show_stack+0x0/0x1c) from [<c05f3a4c>] (dump_stack+0x70/0x8c)
[<c05f39dc>] (dump_stack+0x0/0x8c) from [<c00230a8>] (warn_slowpath_common+0x6c/0x8c)
 r4:df883a60 r3:df86ad00
[<c002303c>] (warn_slowpath_common+0x0/0x8c) from [<c002316c>] (warn_slowpath_fmt+0x38/0x40)
 r8:ffffffff r7:00001000 r6:c083b808 r5:00000000 r4:df2efe80
[<c0023134>] (warn_slowpath_fmt+0x0/0x40) from [<c00196bc>] (__dma_alloc+0x200/0x240)
 r3:00000000 r2:c05fda00
[<c00194bc>] (__dma_alloc+0x0/0x240) from [<c001982c>] (arm_dma_alloc+0x88/0xa0)
[<c00197a4>] (arm_dma_alloc+0x0/0xa0) from [<c03e2904>] (ehci_setup+0x1f4/0x438)
[<c03e2710>] (ehci_setup+0x0/0x438) from [<c03cbd60>] (usb_add_hcd+0x18c/0x664)
[<c03cbbd4>] (usb_add_hcd+0x0/0x664) from [<c03e89f4>] (host_start+0xf0/0x180)
[<c03e8904>] (host_start+0x0/0x180) from [<c03e7c34>] (ci_hdrc_probe+0x360/0x670
)
 r6:df2ef410 r5:00000000 r4:df2c3010 r3:c03e8904
[<c03e78d4>] (ci_hdrc_probe+0x0/0x670) from [<c0311044>] (platform_drv_probe+0x20/0x24)
[<c0311024>] (platform_drv_probe+0x0/0x24) from [<c030fcac>] (driver_probe_device+0x9c/0x234)
...
---[ end trace c88ccaf3969e8422 ]---
Unable to handle kernel NULL pointer dereference at virtual address 00000028
pgd = c0004000
[00000028] *pgd=00000000
Internal error: Oops: 17 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 6 Comm: kworker/u2:0 Tainted: G        W    3.12.0-rc4+ #56
Workqueue: deferwq deferred_probe_work_func
task: df86ad00 ti: df882000 task.ti: df882000
PC is at usb_remove_hcd+0x10/0x150
LR is at host_stop+0x1c/0x3c
pc : [<c03cacec>]    lr : [<c03e88e4>]    psr: 60000013
sp : df883b50  ip : df883b78  fp : df883b74
r10: c11f4c54  r9 : c0836450  r8 : df30c400
r7 : fffffff4  r6 : df2ef410  r5 : 00000000  r4 : df2c3010
r3 : 00000000  r2 : 00000000  r1 : df86b0a0  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 2f29404a  DAC: 00000015
Process kworker/u2:0 (pid: 6, stack limit = 0xdf882240)
Stack: (0xdf883b50 to 0xdf884000)
...
Backtrace:
[<c03cacdc>] (usb_remove_hcd+0x0/0x150) from [<c03e88e4>] (host_stop+0x1c/0x3c)
 r6:df2ef410 r5:00000000 r4:df2c3010
[<c03e88c8>] (host_stop+0x0/0x3c) from [<c03e8aa0>] (ci_hdrc_host_destroy+0x1c/0x20)
 r5:00000000 r4:df2c3010
[<c03e8a84>] (ci_hdrc_host_destroy+0x0/0x20) from [<c03e7c80>] (ci_hdrc_probe+0x3ac/0x670)
[<c03e78d4>] (ci_hdrc_probe+0x0/0x670) from [<c0311044>] (platform_drv_probe+0x20/0x24)
[<c0311024>] (platform_drv_probe+0x0/0x24) from [<c030fcac>] (driver_probe_device+0x9c/0x234)
[<c030fc10>] (driver_probe_device+0x0/0x234) from [<c030ff28>] (__device_attach+0x44/0x48)
...
---[ end trace c88ccaf3969e8423 ]---

Fix this so at least we can continue booting and get to a shell prompt.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Nov 12, 2013
As the new x86 CPU bootup printout format code maintainer, I am
taking immediate action to improve and clean (and thus indulge
my OCD) the reporting of the cores when coming up online.

Fix padding to a right-hand alignment, cleanup code and bind
reporting width to the max number of supported CPUs on the
system, like this:

 [    0.074509] smpboot: Booting Node   0, Processors:      #1  #2  #3  #4  #5  #6  #7 OK
 [    0.644008] smpboot: Booting Node   1, Processors:  #8  #9 #10 #11 #12 #13 #14 #15 OK
 [    1.245006] smpboot: Booting Node   2, Processors: #16 #17 #18 #19 #20 #21 #22 #23 OK
 [    1.864005] smpboot: Booting Node   3, Processors: #24 #25 #26 #27 #28 #29 #30 #31 OK
 [    2.489005] smpboot: Booting Node   4, Processors: #32 #33 #34 #35 #36 #37 #38 #39 OK
 [    3.093005] smpboot: Booting Node   5, Processors: #40 #41 #42 #43 #44 #45 #46 #47 OK
 [    3.698005] smpboot: Booting Node   6, Processors: #48 #49 #50 #51 #52 #53 #54 #55 OK
 [    4.304005] smpboot: Booting Node   7, Processors: #56 #57 #58 #59 #60 #61 #62 #63 OK
 [    4.961413] Brought up 64 CPUs

and this:

 [    0.072367] smpboot: Booting Node   0, Processors:    #1 #2 #3 #4 #5 #6 #7 OK
 [    0.686329] Brought up 8 CPUs

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Libin <huawei.libin@huawei.com>
Cc: wangyijing@huawei.com
Cc: fenghua.yu@intel.com
Cc: guohanjun@huawei.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/20130927143554.GF4422@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
amery pushed a commit that referenced this issue Nov 12, 2013
Turn it into (for example):

[    0.073380] x86: Booting SMP configuration:
[    0.074005] .... node   #0, CPUs:          #1   #2   #3   #4   #5   #6   #7
[    0.603005] .... node   #1, CPUs:     #8   #9  #10  #11  #12  #13  #14  #15
[    1.200005] .... node   #2, CPUs:    #16  #17  #18  #19  #20  #21  #22  #23
[    1.796005] .... node   #3, CPUs:    #24  #25  #26  #27  #28  #29  #30  #31
[    2.393005] .... node   #4, CPUs:    #32  #33  #34  #35  #36  #37  #38  #39
[    2.996005] .... node   #5, CPUs:    #40  #41  #42  #43  #44  #45  #46  #47
[    3.600005] .... node   #6, CPUs:    #48  #49  #50  #51  #52  #53  #54  #55
[    4.202005] .... node   #7, CPUs:    #56  #57  #58  #59  #60  #61  #62  #63
[    4.811005] .... node   #8, CPUs:    #64  #65  #66  #67  #68  #69  #70  #71
[    5.421006] .... node   #9, CPUs:    #72  #73  #74  #75  #76  #77  #78  #79
[    6.032005] .... node  #10, CPUs:    #80  #81  #82  #83  #84  #85  #86  #87
[    6.648006] .... node  #11, CPUs:    #88  #89  #90  #91  #92  #93  #94  #95
[    7.262005] .... node  #12, CPUs:    #96  #97  #98  #99 #100 #101 #102 #103
[    7.865005] .... node  #13, CPUs:   #104 #105 #106 #107 #108 #109 #110 #111
[    8.466005] .... node  #14, CPUs:   #112 #113 #114 #115 #116 #117 #118 #119
[    9.073006] .... node  #15, CPUs:   #120 #121 #122 #123 #124 #125 #126 #127
[    9.679901] x86: Booted up 16 nodes, 128 CPUs

and drop useless elements.

Change num_digits() to hpa's division-avoiding, cell-phone-typed
version which he went at great lengths and pains to submit on a
Saturday evening.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: huawei.libin@huawei.com
Cc: wangyijing@huawei.com
Cc: fenghua.yu@intel.com
Cc: guohanjun@huawei.com
Cc: paul.gortmaker@windriver.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130930095624.GB16383@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
turl referenced this issue in allwinner-dev-team/linux-allwinner Jan 28, 2014
…p() properly shutdown

request_queue is refcounted but actually depdends on lifetime
management from the queue owner - on blk_cleanup_queue(), block layer
expects that there's no request passing through request_queue and no
new one will.

This is fundamentally broken.  The queue owner (e.g. SCSI layer)
doesn't have a way to know whether there are other active users before
calling blk_cleanup_queue() and other users (e.g. bsg) don't have any
guarantee that the queue is and would stay valid while it's holding a
reference.

With delay added in blk_queue_bio() before queue_lock is grabbed, the
following oops can be easily triggered when a device is removed with
in-flight IOs.

 sd 0:0:1:0: [sdb] Stopping disk
 ata1.01: disabled
 general protection fault: 0000 [#1] PREEMPT SMP
 CPU 2
 Modules linked in:

 Pid: 648, comm: test_rawio Not tainted 3.1.0-rc3-work+ torvalds#56 Bochs Bochs
 RIP: 0010:[<ffffffff8137d651>]  [<ffffffff8137d651>] elv_rqhash_find+0x61/0x100
 ...
 Process test_rawio (pid: 648, threadinfo ffff880019efa000, task ffff880019ef8a80)
 ...
 Call Trace:
  [<ffffffff8137d774>] elv_merge+0x84/0xe0
  [<ffffffff81385b54>] blk_queue_bio+0xf4/0x400
  [<ffffffff813838ea>] generic_make_request+0xca/0x100
  [<ffffffff81383994>] submit_bio+0x74/0x100
  [<ffffffff811c53ec>] dio_bio_submit+0xbc/0xc0
  [<ffffffff811c610e>] __blockdev_direct_IO+0x92e/0xb40
  [<ffffffff811c39f7>] blkdev_direct_IO+0x57/0x60
  [<ffffffff8113b1c5>] generic_file_aio_read+0x6d5/0x760
  [<ffffffff8118c1ca>] do_sync_read+0xda/0x120
  [<ffffffff8118ce55>] vfs_read+0xc5/0x180
  [<ffffffff8118cfaa>] sys_pread64+0x9a/0xb0
  [<ffffffff81afaf6b>] system_call_fastpath+0x16/0x1b

This happens because blk_queue_cleanup() destroys the queue and
elevator whether IOs are in progress or not and DEAD tests are
sprinkled in the request processing path without proper
synchronization.

Similar problem exists for blk-throtl.  On queue cleanup, blk-throtl
is shutdown whether it has requests in it or not.  Depending on
timing, it either oopses or throttled bios are lost putting tasks
which are waiting for bio completion into eternal D state.

The way it should work is having the usual clear distinction between
shutdown and release.  Shutdown drains all currently pending requests,
marks the queue dead, and performs partial teardown of the now
unnecessary part of the queue.  Even after shutdown is complete,
reference holders are still allowed to issue requests to the queue
although they will be immmediately failed.  The rest of teardown
happens on release.

This patch makes the following changes to make blk_queue_cleanup()
behave as proper shutdown.

* QUEUE_FLAG_DEAD is now set while holding both q->exit_mutex and
  queue_lock.

* Unsynchronized DEAD check in generic_make_request_checks() removed.
  This couldn't make any meaningful difference as the queue could die
  after the check.

* blk_drain_queue() updated such that it can drain all requests and is
  now called during cleanup.

* blk_throtl updated such that it checks DEAD on grabbing queue_lock,
  drains all throttled bios during cleanup and free td when queue is
  released.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
amery pushed a commit that referenced this issue Nov 22, 2014
Kernel dump (WARN_ON) ocurred during system boot-up inside regmap_write():

------------[ cut here ]------------
WARNING: CPU: 0 PID: 47 at kernel/locking/lockdep.c:2744 lockdep_trace_alloc+0xe8/0x108()
DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
Modules linked in:
CPU: 0 PID: 47 Comm: kworker/u2:2 Not tainted 3.18.0-rc1-10245-gb75d289-dirty #56
Workqueue: deferwq deferred_probe_work_func
Backtrace:
[<80012294>] (dump_backtrace) from [<80012578>] (show_stack+0x18/0x1c)
 r6:8097c73c r5:8097c73c r4:00000000 r3:be33ba80
[<80012560>] (show_stack) from [<806aac48>] (dump_stack+0x8c/0xa4)
[<806aabbc>] (dump_stack) from [<8002a694>] (warn_slowpath_common+0x70/0x94)
 r6:80062838 r5:00000009 r4:bd827b30 r3:be33ba80
[<8002a624>] (warn_slowpath_common) from [<8002a6f0>] (warn_slowpath_fmt+0x38/0x40)
 r8:00000004 r7:00000001 r6:000080d0 r5:60000193 r4:bd826010
[<8002a6bc>] (warn_slowpath_fmt) from [<80062838>] (lockdep_trace_alloc+0xe8/0x108)
 r3:80831590 r2:8082e160
[<80062750>] (lockdep_trace_alloc) from [<800ea5dc>] (kmem_cache_alloc+0x28/0x134)
 r5:000080d0 r4:be001f00
[<800ea5b4>] (kmem_cache_alloc) from [<8038d72c>] (regcache_rbtree_write+0x15c/0x648)
 r10:00000000 r9:0000001c r8:00000004 r7:00000001 r6:00000000 r5:bd819a00
 r4:00000000 r3:811aea88
[<8038d5d0>] (regcache_rbtree_write) from [<8038c4d8>] (regcache_write+0x5c/0x64)
 r10:be3f9f88 r9:00000000 r8:00000004 r7:00000001 r6:00000000 r5:00000001
 r4:bd819a00
[<8038c47c>] (regcache_write) from [<8038b0dc>] (_regmap_raw_write+0x134/0x5f4)
 r6:be3f9f84 r5:00000001 r4:bd819a00 r3:00000001
[<8038afa8>] (_regmap_raw_write) from [<8038b610>] (_regmap_bus_raw_write+0x74/0x94)
 r10:00000000 r9:00000001 r8:be3fb080 r7:bd819a00 r6:00000001 r5:00000000
 r4:bd819a00
[<8038b59c>] (_regmap_bus_raw_write) from [<8038a8b4>] (_regmap_write+0x60/0x9c)
 r6:00000001 r5:00000000 r4:bd819a00 r3:8038b59c
[<8038a854>] (_regmap_write) from [<8038ba24>] (regmap_write+0x48/0x68)
 r7:bd81ad80 r6:00000001 r5:00000000 r4:bd819a00
[<8038b9dc>] (regmap_write) from [<80528f30>] (fsl_asrc_dai_probe+0x34/0x104)
 r6:bd888628 r5:be3fb080 r4:be3b4410 r3:be3b442c
------------[ dump end ]------------

=============================================================================
2741         /*
2742          * Oi! Can't be having __GFP_FS allocations with IRQs disabled.
2743          */
2744         if (DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags)))
2745                 return;
=============================================================================

By looking at 2744 line, we can get that it's because regcache_rbtree_write()
would call kmalloc() with GFP flag if it couldn't find an existing block to
insert nodes while this kmalloc() call is inside a spin_lock_irq_save pair,
i.e. IRQs disabled.

Even though this may be a bug that should be fixed, I still try to send this
patch as a quick fix (work around) since it does no harm to assign default
values of every registers when using regcache.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
wens pushed a commit that referenced this issue Dec 2, 2016
The breadcrumbs are about to be used from within IRQ context sections
(e.g. nouveau signals a fence from an interrupt handler causing us to
submit a new request) and/or from bottom-half tasklets (i.e.
intel_lrc_irq_handler), therefore we need to employ the irqsafe spinlock
variants.

For example, deferring the request submission to the
intel_lrc_irq_handler generates this trace:

[   66.388639] =================================
[   66.388650] [ INFO: inconsistent lock state ]
[   66.388663] 4.9.0-rc2+ #56 Not tainted
[   66.388672] ---------------------------------
[   66.388682] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   66.388695] swapper/1/0 [HC0[0]:SC1[1]:HE0:SE0] takes:
[   66.388706]  (&(&b->lock)->rlock){+.?...} , at: [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.388761] {SOFTIRQ-ON-W} state was registered at:
[   66.388772]   [   66.388783] [<ffffffff810bd842>] __lock_acquire+0x682/0x1870
[   66.388795]   [   66.388803] [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.388814]   [   66.388824] [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.388835]   [   66.388845] [<ffffffff81401e41>] intel_engine_reset_breadcrumbs+0x21/0xb0
[   66.388857]   [   66.388866] [<ffffffff81403ae7>] gen8_init_common_ring+0x67/0x100
[   66.388878]   [   66.388887] [<ffffffff81403b92>] gen8_init_render_ring+0x12/0x60
[   66.388903]   [   66.388912] [<ffffffff813f8707>] i915_gem_init_hw+0xf7/0x2a0
[   66.388927]   [   66.388936] [<ffffffff813f899b>] i915_gem_init+0xbb/0xf0
[   66.388950]   [   66.388959] [<ffffffff813b4980>] i915_driver_load+0x7e0/0x1330
[   66.388978]   [   66.388988] [<ffffffff813c09d8>] i915_pci_probe+0x28/0x40
[   66.389003]   [   66.389013] [<ffffffff812fa0db>] pci_device_probe+0x8b/0xf0
[   66.389028]   [   66.389037] [<ffffffff8147737e>] driver_probe_device+0x21e/0x430
[   66.389056]   [   66.389065] [<ffffffff8147766e>] __driver_attach+0xde/0xe0
[   66.389080]   [   66.389090] [<ffffffff814751ad>] bus_for_each_dev+0x5d/0x90
[   66.389105]   [   66.389113] [<ffffffff81477799>] driver_attach+0x19/0x20
[   66.389134]   [   66.389144] [<ffffffff81475ced>] bus_add_driver+0x15d/0x260
[   66.389159]   [   66.389168] [<ffffffff81477e3b>] driver_register+0x5b/0xd0
[   66.389183]   [   66.389281] [<ffffffff812fa19b>] __pci_register_driver+0x5b/0x60
[   66.389301]   [   66.389312] [<ffffffff81aed333>] i915_init+0x3e/0x45
[   66.389326]   [   66.389336] [<ffffffff81ac2ffa>] do_one_initcall+0x8b/0x118
[   66.389350]   [   66.389359] [<ffffffff81ac323a>] kernel_init_freeable+0x1b3/0x23b
[   66.389378]   [   66.389387] [<ffffffff8160fc39>] kernel_init+0x9/0x100
[   66.389402]   [   66.389411] [<ffffffff816180e7>] ret_from_fork+0x27/0x40
[   66.389426] irq event stamp: 315865
[   66.389438] hardirqs last  enabled at (315864): [<ffffffff816178f1>] _raw_spin_unlock_irqrestore+0x31/0x50
[   66.389469] hardirqs last disabled at (315865): [<ffffffff816176b3>] _raw_spin_lock_irqsave+0x13/0x50
[   66.389499] softirqs last  enabled at (315818): [<ffffffff8107a04c>] _local_bh_enable+0x1c/0x50
[   66.389530] softirqs last disabled at (315819): [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.389559]
[   66.389559] other info that might help us debug this:
[   66.389580]  Possible unsafe locking scenario:
[   66.389580]
[   66.389598]        CPU0
[   66.389609]        ----
[   66.389620]   lock(&(&b->lock)->rlock);
[   66.389650]   <Interrupt>
[   66.389661]     lock(&(&b->lock)->rlock);
[   66.389690]
[   66.389690]  *** DEADLOCK ***
[   66.389690]
[   66.389715] 2 locks held by swapper/1/0:
[   66.389728]  #0: (&(&tl->lock)->rlock){..-...}, at: [<ffffffff81403e01>] intel_lrc_irq_handler+0x201/0x3c0
[   66.389785]  #1: (&(&req->lock)->rlock/1){..-...}, at: [<ffffffff813fc0af>] __i915_gem_request_submit+0x8f/0x170
[   66.389854]
[   66.389854] stack backtrace:
[   66.389959] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.0-rc2+ #56
[   66.389976] Hardware name:                  /        , BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[   66.389999]  ffff88027fd03c58 ffffffff812beae5 ffff88027696e680 ffffffff822afe20
[   66.390036]  ffff88027fd03ca8 ffffffff810bb420 0000000000000001 0000000000000000
[   66.390070]  0000000000000000 0000000000000006 0000000000000004 ffff88027696ee10
[   66.390104] Call Trace:
[   66.390117]  <IRQ>
[   66.390128]  [<ffffffff812beae5>] dump_stack+0x68/0x93
[   66.390147]  [<ffffffff810bb420>] print_usage_bug+0x1d0/0x1e0
[   66.390164]  [<ffffffff810bb8a0>] mark_lock+0x470/0x4f0
[   66.390181]  [<ffffffff810ba9d0>] ? print_shortest_lock_dependencies+0x1b0/0x1b0
[   66.390203]  [<ffffffff810bd75d>] __lock_acquire+0x59d/0x1870
[   66.390221]  [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.390237]  [<ffffffff810bedbc>] ? lock_acquire+0x6c/0xb0
[   66.390255]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390273]  [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.390291]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390309]  [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.390327]  [<ffffffff813fc170>] __i915_gem_request_submit+0x150/0x170
[   66.390345]  [<ffffffff81403e8b>] intel_lrc_irq_handler+0x28b/0x3c0
[   66.390363]  [<ffffffff81079d97>] tasklet_action+0x57/0xc0
[   66.390380]  [<ffffffff8107a249>] __do_softirq+0x119/0x240
[   66.390396]  [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.390414]  [<ffffffff8101afd5>] do_IRQ+0x65/0x110
[   66.390431]  [<ffffffff81618806>] common_interrupt+0x86/0x86
[   66.390446]  <EOI>
[   66.390457]  [<ffffffff814ec6d1>] ? cpuidle_enter_state+0x151/0x200
[   66.390480]  [<ffffffff814ec7a2>] cpuidle_enter+0x12/0x20
[   66.390498]  [<ffffffff810b639e>] call_cpuidle+0x1e/0x40
[   66.390516]  [<ffffffff810b65ae>] cpu_startup_entry+0x10e/0x1f0
[   66.390534]  [<ffffffff81036133>] start_secondary+0x103/0x130

(This is split out of the defer global seqno allocation patch due to
realisation that we need a more complete conversion if we want to defer
request submission even further.)

v2: lockdep was warning about mixed SOFTIRQ contexts not HARDIRQ
contexts so we only need to use spin_lock_bh and not disable interrupts.

v3: We need full irq protection as we may be called from a third party
interrupt handler (via fences).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-32-chris@chris-wilson.co.uk
amery pushed a commit that referenced this issue Jul 28, 2017
The following warning was triggered by missing srcu locks around
the storage key handling functions.

=============================
WARNING: suspicious RCU usage
4.12.0+ #56 Not tainted
-----------------------------
./include/linux/kvm_host.h:572 suspicious rcu_dereference_check() usage!
rcu_scheduler_active = 2, debug_locks = 1
 1 lock held by live_migration/4936:
  #0:  (&mm->mmap_sem){++++++}, at: [<0000000000141be0>]
kvm_arch_vm_ioctl+0x6b8/0x22d0

 CPU: 8 PID: 4936 Comm: live_migration Not tainted 4.12.0+ #56
 Hardware name: IBM 2964 NC9 704 (LPAR)
 Call Trace:
 ([<000000000011378a>] show_stack+0xea/0xf0)
  [<000000000055cc4c>] dump_stack+0x94/0xd8
  [<000000000012ee70>] gfn_to_memslot+0x1a0/0x1b8
  [<0000000000130b76>] gfn_to_hva+0x2e/0x48
  [<0000000000141c3c>] kvm_arch_vm_ioctl+0x714/0x22d0
  [<000000000013306c>] kvm_vm_ioctl+0x11c/0x7b8
  [<000000000037e2c0>] do_vfs_ioctl+0xa8/0x6c8
  [<000000000037e984>] SyS_ioctl+0xa4/0xb8
  [<00000000008b20a4>] system_call+0xc4/0x27c
 1 lock held by live_migration/4936:
  #0:  (&mm->mmap_sem){++++++}, at: [<0000000000141be0>]
kvm_arch_vm_ioctl+0x6b8/0x22d0

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Pierre Morel<pmorel@linux.vnet.ibm.com>
amery pushed a commit that referenced this issue Sep 1, 2017
The below commit added a call to ->destroy() on init failure, but multiq
still frees ->queues on error in init, but ->queues is also freed by
->destroy() thus we get double free and corrupted memory.

Very easy to reproduce (eth0 not multiqueue):
$ tc qdisc add dev eth0 root multiq
RTNETLINK answers: Operation not supported
$ ip l add dumdum type dummy
(crash)

Trace log:
[ 3929.467747] general protection fault: 0000 [#1] SMP
[ 3929.468083] Modules linked in:
[ 3929.468302] CPU: 3 PID: 967 Comm: ip Not tainted 4.13.0-rc6+ #56
[ 3929.468625] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 3929.469124] task: ffff88003716a700 task.stack: ffff88005872c000
[ 3929.469449] RIP: 0010:__kmalloc_track_caller+0x117/0x1be
[ 3929.469746] RSP: 0018:ffff88005872f6a0 EFLAGS: 00010246
[ 3929.470042] RAX: 00000000000002de RBX: 0000000058a59000 RCX: 00000000000002df
[ 3929.470406] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff821f7020
[ 3929.470770] RBP: ffff88005872f6e8 R08: 000000000001f010 R09: 0000000000000000
[ 3929.471133] R10: ffff88005872f730 R11: 0000000000008cdd R12: ff006d75646d7564
[ 3929.471496] R13: 00000000014000c0 R14: ffff88005b403c00 R15: ffff88005b403c00
[ 3929.471869] FS:  00007f0b70480740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000
[ 3929.472286] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3929.472677] CR2: 00007ffcee4f3000 CR3: 0000000059d45000 CR4: 00000000000406e0
[ 3929.473209] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 3929.474109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 3929.474873] Call Trace:
[ 3929.475337]  ? kstrdup_const+0x23/0x25
[ 3929.475863]  kstrdup+0x2e/0x4b
[ 3929.476338]  kstrdup_const+0x23/0x25
[ 3929.478084]  __kernfs_new_node+0x28/0xbc
[ 3929.478478]  kernfs_new_node+0x35/0x55
[ 3929.478929]  kernfs_create_link+0x23/0x76
[ 3929.479478]  sysfs_do_create_link_sd.isra.2+0x85/0xd7
[ 3929.480096]  sysfs_create_link+0x33/0x35
[ 3929.480649]  device_add+0x200/0x589
[ 3929.481184]  netdev_register_kobject+0x7c/0x12f
[ 3929.481711]  register_netdevice+0x373/0x471
[ 3929.482174]  rtnl_newlink+0x614/0x729
[ 3929.482610]  ? rtnl_newlink+0x17f/0x729
[ 3929.483080]  rtnetlink_rcv_msg+0x188/0x197
[ 3929.483533]  ? rcu_read_unlock+0x3e/0x5f
[ 3929.483984]  ? rtnl_newlink+0x729/0x729
[ 3929.484420]  netlink_rcv_skb+0x6c/0xce
[ 3929.484858]  rtnetlink_rcv+0x23/0x2a
[ 3929.485291]  netlink_unicast+0x103/0x181
[ 3929.485735]  netlink_sendmsg+0x326/0x337
[ 3929.486181]  sock_sendmsg_nosec+0x14/0x3f
[ 3929.486614]  sock_sendmsg+0x29/0x2e
[ 3929.486973]  ___sys_sendmsg+0x209/0x28b
[ 3929.487340]  ? do_raw_spin_unlock+0xcd/0xf8
[ 3929.487719]  ? _raw_spin_unlock+0x27/0x31
[ 3929.488092]  ? __handle_mm_fault+0x651/0xdb1
[ 3929.488471]  ? check_chain_key+0xb0/0xfd
[ 3929.488847]  __sys_sendmsg+0x45/0x63
[ 3929.489206]  ? __sys_sendmsg+0x45/0x63
[ 3929.489576]  SyS_sendmsg+0x19/0x1b
[ 3929.489901]  entry_SYSCALL_64_fastpath+0x23/0xc2
[ 3929.490172] RIP: 0033:0x7f0b6fb93690
[ 3929.490423] RSP: 002b:00007ffcee4ed588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 3929.490881] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f0b6fb93690
[ 3929.491198] RDX: 0000000000000000 RSI: 00007ffcee4ed5d0 RDI: 0000000000000003
[ 3929.491521] RBP: ffff88005872ff98 R08: 0000000000000001 R09: 0000000000000000
[ 3929.491801] R10: 00007ffcee4ed350 R11: 0000000000000246 R12: 0000000000000002
[ 3929.492075] R13: 000000000066f1a0 R14: 00007ffcee4f5680 R15: 0000000000000000
[ 3929.492352]  ? trace_hardirqs_off_caller+0xa7/0xcf
[ 3929.492590] Code: 8b 45 c0 48 8b 45 b8 74 17 48 8b 4d c8 83 ca ff 44
89 ee 4c 89 f7 e8 83 ca ff ff 49 89 c4 eb 49 49 63 56 20 48 8d 48 01 4d
8b 06 <49> 8b 1c 14 48 89 c2 4c 89 e0 65 49 0f c7 08 0f 94 c0 83 f0 01
[ 3929.493335] RIP: __kmalloc_track_caller+0x117/0x1be RSP: ffff88005872f6a0

Fixes: 87b60cf ("net_sched: fix error recovery at qdisc creation")
Fixes: f07d150 ("multiq: Further multiqueue cleanup")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
amery pushed a commit that referenced this issue Sep 7, 2017
Commit d300627 ("powerpc/6xx: Handle DABR match before calling
do_page_fault") breaks non 6xx platforms.

  Failed to execute /init (error -14)
  Starting init: /bin/sh exists but couldn't execute it (error -14)
  Kernel panic - not syncing: No working init found.  Try passing init= ...
  CPU: 0 PID: 1 Comm: init Not tainted 4.13.0-rc3-s3k-dev-00143-g7aa62e972a56 #56
  Call Trace:
    panic+0x108/0x250 (unreliable)
    rootfs_mount+0x0/0x58
    ret_from_kernel_thread+0x5c/0x64
  Rebooting in 180 seconds..

This is because in handle_page_fault(), the call to do_page_fault() has been
mistakenly enclosed inside an #ifdef CONFIG_6xx

Fixes: d300627 ("powerpc/6xx: Handle DABR match before calling do_page_fault")
Brown-paper-bag-to-be-worn-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
amery pushed a commit that referenced this issue Nov 9, 2017
A CDC Ethernet functional descriptor with wMaxSegmentSize = 0 will
cause a divide error in usbnet_probe:

divide error: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc8-44453-g1fdc1a82c34f #56
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: usb_hub_wq hub_event
task: ffff88006bef5c00 task.stack: ffff88006bf60000
RIP: 0010:usbnet_update_max_qlen+0x24d/0x390 drivers/net/usb/usbnet.c:355
RSP: 0018:ffff88006bf67508 EFLAGS: 00010246
RAX: 00000000000163c8 RBX: ffff8800621fce40 RCX: ffff8800621fcf34
RDX: 0000000000000000 RSI: ffffffff837ecb7a RDI: ffff8800621fcf34
RBP: ffff88006bf67520 R08: ffff88006bef5c00 R09: ffffed000c43f881
R10: ffffed000c43f880 R11: ffff8800621fc406 R12: 0000000000000003
R13: ffffffff85c71de0 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88006ca00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe9c0d6dac CR3: 00000000614f4000 CR4: 00000000000006f0
Call Trace:
 usbnet_probe+0x18b5/0x2790 drivers/net/usb/usbnet.c:1783
 qmi_wwan_probe+0x133/0x220 drivers/net/usb/qmi_wwan.c:1338
 usb_probe_interface+0x324/0x940 drivers/usb/core/driver.c:361
 really_probe drivers/base/dd.c:413
 driver_probe_device+0x522/0x740 drivers/base/dd.c:557

Fix by simply ignoring the bogus descriptor, as it is optional
for QMI devices anyway.

Fixes: 423ce8c ("net: usb: qmi_wwan: New driver for Huawei QMI based WWAN devices")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
amery pushed a commit that referenced this issue Feb 22, 2018
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: 3832125 ("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>
jer-gentoo pushed a commit to MI-Group/linux-sunxi that referenced this issue Mar 12, 2018
commit e89d469 upstream.

The below commit added a call to ->destroy() on init failure, but multiq
still frees ->queues on error in init, but ->queues is also freed by
->destroy() thus we get double free and corrupted memory.

Very easy to reproduce (eth0 not multiqueue):
$ tc qdisc add dev eth0 root multiq
RTNETLINK answers: Operation not supported
$ ip l add dumdum type dummy
(crash)

Trace log:
[ 3929.467747] general protection fault: 0000 [linux-sunxi#1] SMP
[ 3929.468083] Modules linked in:
[ 3929.468302] CPU: 3 PID: 967 Comm: ip Not tainted 4.13.0-rc6+ linux-sunxi#56
[ 3929.468625] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 3929.469124] task: ffff88003716a700 task.stack: ffff88005872c000
[ 3929.469449] RIP: 0010:__kmalloc_track_caller+0x117/0x1be
[ 3929.469746] RSP: 0018:ffff88005872f6a0 EFLAGS: 00010246
[ 3929.470042] RAX: 00000000000002de RBX: 0000000058a59000 RCX:
00000000000002df
[ 3929.470406] RDX: 0000000000000000 RSI: 0000000000000000 RDI:
ffffffff821f7020
[ 3929.470770] RBP: ffff88005872f6e8 R08: 000000000001f010 R09:
0000000000000000
[ 3929.471133] R10: ffff88005872f730 R11: 0000000000008cdd R12:
ff006d75646d7564
[ 3929.471496] R13: 00000000014000c0 R14: ffff88005b403c00 R15:
ffff88005b403c00
[ 3929.471869] FS:  00007f0b70480740(0000) GS:ffff88005d980000(0000)
knlGS:0000000000000000
[ 3929.472286] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3929.472677] CR2: 00007ffcee4f3000 CR3: 0000000059d45000 CR4:
00000000000406e0
[ 3929.473209] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 3929.474109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 3929.474873] Call Trace:
[ 3929.475337]  ? kstrdup_const+0x23/0x25
[ 3929.475863]  kstrdup+0x2e/0x4b
[ 3929.476338]  kstrdup_const+0x23/0x25
[ 3929.478084]  __kernfs_new_node+0x28/0xbc
[ 3929.478478]  kernfs_new_node+0x35/0x55
[ 3929.478929]  kernfs_create_link+0x23/0x76
[ 3929.479478]  sysfs_do_create_link_sd.isra.2+0x85/0xd7
[ 3929.480096]  sysfs_create_link+0x33/0x35
[ 3929.480649]  device_add+0x200/0x589
[ 3929.481184]  netdev_register_kobject+0x7c/0x12f
[ 3929.481711]  register_netdevice+0x373/0x471
[ 3929.482174]  rtnl_newlink+0x614/0x729
[ 3929.482610]  ? rtnl_newlink+0x17f/0x729
[ 3929.483080]  rtnetlink_rcv_msg+0x188/0x197
[ 3929.483533]  ? rcu_read_unlock+0x3e/0x5f
[ 3929.483984]  ? rtnl_newlink+0x729/0x729
[ 3929.484420]  netlink_rcv_skb+0x6c/0xce
[ 3929.484858]  rtnetlink_rcv+0x23/0x2a
[ 3929.485291]  netlink_unicast+0x103/0x181
[ 3929.485735]  netlink_sendmsg+0x326/0x337
[ 3929.486181]  sock_sendmsg_nosec+0x14/0x3f
[ 3929.486614]  sock_sendmsg+0x29/0x2e
[ 3929.486973]  ___sys_sendmsg+0x209/0x28b
[ 3929.487340]  ? do_raw_spin_unlock+0xcd/0xf8
[ 3929.487719]  ? _raw_spin_unlock+0x27/0x31
[ 3929.488092]  ? __handle_mm_fault+0x651/0xdb1
[ 3929.488471]  ? check_chain_key+0xb0/0xfd
[ 3929.488847]  __sys_sendmsg+0x45/0x63
[ 3929.489206]  ? __sys_sendmsg+0x45/0x63
[ 3929.489576]  SyS_sendmsg+0x19/0x1b
[ 3929.489901]  entry_SYSCALL_64_fastpath+0x23/0xc2
[ 3929.490172] RIP: 0033:0x7f0b6fb93690
[ 3929.490423] RSP: 002b:00007ffcee4ed588 EFLAGS: 00000246 ORIG_RAX:
000000000000002e
[ 3929.490881] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX:
00007f0b6fb93690
[ 3929.491198] RDX: 0000000000000000 RSI: 00007ffcee4ed5d0 RDI:
0000000000000003
[ 3929.491521] RBP: ffff88005872ff98 R08: 0000000000000001 R09:
0000000000000000
[ 3929.491801] R10: 00007ffcee4ed350 R11: 0000000000000246 R12:
0000000000000002
[ 3929.492075] R13: 000000000066f1a0 R14: 00007ffcee4f5680 R15:
0000000000000000
[ 3929.492352]  ? trace_hardirqs_off_caller+0xa7/0xcf
[ 3929.492590] Code: 8b 45 c0 48 8b 45 b8 74 17 48 8b 4d c8 83 ca ff 44
89 ee 4c 89 f7 e8 83 ca ff ff 49 89 c4 eb 49 49 63 56 20 48 8d 48 01 4d
8b 06 <49> 8b 1c 14 48 89 c2 4c 89 e0 65 49 0f c7 08 0f 94 c0 83 f0 01
[ 3929.493335] RIP: __kmalloc_track_caller+0x117/0x1be RSP:
ffff88005872f6a0

Fixes: 87b60cf ("net_sched: fix error recovery at qdisc creation")
Fixes: f07d150 ("multiq: Further multiqueue cleanup")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: delete now-unused 'err' variable]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
codekipper pushed a commit to codekipper/linux-sunxi that referenced this issue Jul 29, 2019
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
linux-sunxi#42: FILE: fs/ocfs2/aops.c:2155:
+	unsigned i_blkbits = inode->i_sb->s_blocksize_bits;

ERROR: code indent should use tabs where possible
linux-sunxi#53: FILE: fs/ocfs2/aops.c:2166:
+ ^I * "pos" and "end", we need map twice to return different buffer state:$

WARNING: please, no space before tabs
linux-sunxi#53: FILE: fs/ocfs2/aops.c:2166:
+ ^I * "pos" and "end", we need map twice to return different buffer state:$

ERROR: code indent should use tabs where possible
linux-sunxi#54: FILE: fs/ocfs2/aops.c:2167:
+ ^I * 1. area in file size, not set NEW;$

WARNING: please, no space before tabs
linux-sunxi#54: FILE: fs/ocfs2/aops.c:2167:
+ ^I * 1. area in file size, not set NEW;$

ERROR: code indent should use tabs where possible
linux-sunxi#55: FILE: fs/ocfs2/aops.c:2168:
+ ^I * 2. area out file size, set  NEW.$

WARNING: please, no space before tabs
linux-sunxi#55: FILE: fs/ocfs2/aops.c:2168:
+ ^I * 2. area out file size, set  NEW.$

ERROR: code indent should use tabs where possible
linux-sunxi#56: FILE: fs/ocfs2/aops.c:2169:
+ ^I *$

WARNING: please, no space before tabs
linux-sunxi#56: FILE: fs/ocfs2/aops.c:2169:
+ ^I *$

ERROR: code indent should use tabs where possible
linux-sunxi#57: FILE: fs/ocfs2/aops.c:2170:
+ ^I *^I^I   iblock    endblk$

WARNING: please, no space before tabs
linux-sunxi#57: FILE: fs/ocfs2/aops.c:2170:
+ ^I *^I^I   iblock    endblk$

ERROR: code indent should use tabs where possible
linux-sunxi#58: FILE: fs/ocfs2/aops.c:2171:
+ ^I * |--------|---------|---------|---------$

WARNING: please, no space before tabs
linux-sunxi#58: FILE: fs/ocfs2/aops.c:2171:
+ ^I * |--------|---------|---------|---------$

ERROR: code indent should use tabs where possible
linux-sunxi#59: FILE: fs/ocfs2/aops.c:2172:
+ ^I * |<-------area in file------->|$

WARNING: please, no space before tabs
linux-sunxi#59: FILE: fs/ocfs2/aops.c:2172:
+ ^I * |<-------area in file------->|$

ERROR: code indent should use tabs where possible
linux-sunxi#60: FILE: fs/ocfs2/aops.c:2173:
+ ^I */$

WARNING: please, no space before tabs
linux-sunxi#60: FILE: fs/ocfs2/aops.c:2173:
+ ^I */$

total: 8 errors, 9 warnings, 40 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

NOTE: Whitespace errors detected.
      You may wish to use scripts/cleanpatch or scripts/cleanfile

./patches/ocfs2-clear-zero-in-unaligned-direct-io.patch has style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Jia Guo <guojia12@huawei.com>
Cc: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
codekipper pushed a commit to codekipper/linux-sunxi that referenced this issue Aug 8, 2019
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
linux-sunxi#42: FILE: fs/ocfs2/aops.c:2155:
+	unsigned i_blkbits = inode->i_sb->s_blocksize_bits;

ERROR: code indent should use tabs where possible
linux-sunxi#53: FILE: fs/ocfs2/aops.c:2166:
+ ^I * "pos" and "end", we need map twice to return different buffer state:$

WARNING: please, no space before tabs
linux-sunxi#53: FILE: fs/ocfs2/aops.c:2166:
+ ^I * "pos" and "end", we need map twice to return different buffer state:$

ERROR: code indent should use tabs where possible
linux-sunxi#54: FILE: fs/ocfs2/aops.c:2167:
+ ^I * 1. area in file size, not set NEW;$

WARNING: please, no space before tabs
linux-sunxi#54: FILE: fs/ocfs2/aops.c:2167:
+ ^I * 1. area in file size, not set NEW;$

ERROR: code indent should use tabs where possible
linux-sunxi#55: FILE: fs/ocfs2/aops.c:2168:
+ ^I * 2. area out file size, set  NEW.$

WARNING: please, no space before tabs
linux-sunxi#55: FILE: fs/ocfs2/aops.c:2168:
+ ^I * 2. area out file size, set  NEW.$

ERROR: code indent should use tabs where possible
linux-sunxi#56: FILE: fs/ocfs2/aops.c:2169:
+ ^I *$

WARNING: please, no space before tabs
linux-sunxi#56: FILE: fs/ocfs2/aops.c:2169:
+ ^I *$

ERROR: code indent should use tabs where possible
linux-sunxi#57: FILE: fs/ocfs2/aops.c:2170:
+ ^I *^I^I   iblock    endblk$

WARNING: please, no space before tabs
linux-sunxi#57: FILE: fs/ocfs2/aops.c:2170:
+ ^I *^I^I   iblock    endblk$

ERROR: code indent should use tabs where possible
linux-sunxi#58: FILE: fs/ocfs2/aops.c:2171:
+ ^I * |--------|---------|---------|---------$

WARNING: please, no space before tabs
linux-sunxi#58: FILE: fs/ocfs2/aops.c:2171:
+ ^I * |--------|---------|---------|---------$

ERROR: code indent should use tabs where possible
linux-sunxi#59: FILE: fs/ocfs2/aops.c:2172:
+ ^I * |<-------area in file------->|$

WARNING: please, no space before tabs
linux-sunxi#59: FILE: fs/ocfs2/aops.c:2172:
+ ^I * |<-------area in file------->|$

ERROR: code indent should use tabs where possible
linux-sunxi#60: FILE: fs/ocfs2/aops.c:2173:
+ ^I */$

WARNING: please, no space before tabs
linux-sunxi#60: FILE: fs/ocfs2/aops.c:2173:
+ ^I */$

total: 8 errors, 9 warnings, 40 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

NOTE: Whitespace errors detected.
      You may wish to use scripts/cleanpatch or scripts/cleanfile

./patches/ocfs2-clear-zero-in-unaligned-direct-io.patch has style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Jia Guo <guojia12@huawei.com>
Cc: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
codekipper pushed a commit to codekipper/linux-sunxi that referenced this issue Aug 16, 2019
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
linux-sunxi#42: FILE: fs/ocfs2/aops.c:2155:
+	unsigned i_blkbits = inode->i_sb->s_blocksize_bits;

ERROR: code indent should use tabs where possible
linux-sunxi#53: FILE: fs/ocfs2/aops.c:2166:
+ ^I * "pos" and "end", we need map twice to return different buffer state:$

WARNING: please, no space before tabs
linux-sunxi#53: FILE: fs/ocfs2/aops.c:2166:
+ ^I * "pos" and "end", we need map twice to return different buffer state:$

ERROR: code indent should use tabs where possible
linux-sunxi#54: FILE: fs/ocfs2/aops.c:2167:
+ ^I * 1. area in file size, not set NEW;$

WARNING: please, no space before tabs
linux-sunxi#54: FILE: fs/ocfs2/aops.c:2167:
+ ^I * 1. area in file size, not set NEW;$

ERROR: code indent should use tabs where possible
linux-sunxi#55: FILE: fs/ocfs2/aops.c:2168:
+ ^I * 2. area out file size, set  NEW.$

WARNING: please, no space before tabs
linux-sunxi#55: FILE: fs/ocfs2/aops.c:2168:
+ ^I * 2. area out file size, set  NEW.$

ERROR: code indent should use tabs where possible
linux-sunxi#56: FILE: fs/ocfs2/aops.c:2169:
+ ^I *$

WARNING: please, no space before tabs
linux-sunxi#56: FILE: fs/ocfs2/aops.c:2169:
+ ^I *$

ERROR: code indent should use tabs where possible
linux-sunxi#57: FILE: fs/ocfs2/aops.c:2170:
+ ^I *^I^I   iblock    endblk$

WARNING: please, no space before tabs
linux-sunxi#57: FILE: fs/ocfs2/aops.c:2170:
+ ^I *^I^I   iblock    endblk$

ERROR: code indent should use tabs where possible
linux-sunxi#58: FILE: fs/ocfs2/aops.c:2171:
+ ^I * |--------|---------|---------|---------$

WARNING: please, no space before tabs
linux-sunxi#58: FILE: fs/ocfs2/aops.c:2171:
+ ^I * |--------|---------|---------|---------$

ERROR: code indent should use tabs where possible
linux-sunxi#59: FILE: fs/ocfs2/aops.c:2172:
+ ^I * |<-------area in file------->|$

WARNING: please, no space before tabs
linux-sunxi#59: FILE: fs/ocfs2/aops.c:2172:
+ ^I * |<-------area in file------->|$

ERROR: code indent should use tabs where possible
linux-sunxi#60: FILE: fs/ocfs2/aops.c:2173:
+ ^I */$

WARNING: please, no space before tabs
linux-sunxi#60: FILE: fs/ocfs2/aops.c:2173:
+ ^I */$

total: 8 errors, 9 warnings, 40 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

NOTE: Whitespace errors detected.
      You may wish to use scripts/cleanpatch or scripts/cleanfile

./patches/ocfs2-clear-zero-in-unaligned-direct-io.patch has style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Jia Guo <guojia12@huawei.com>
Cc: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Dec 23, 2019
…isten()

With multi-transport support, listener sockets are not bound to any
transport. So, calling virtio_transport_reset(), when an error
occurs, on a listener socket produces the following null-pointer
dereference:

  BUG: kernel NULL pointer dereference, address: 00000000000000e8
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  CPU: 0 PID: 20 Comm: kworker/0:1 Not tainted 5.5.0-rc1-ste-00003-gb4be21f316ac-dirty linux-sunxi#56
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
  Workqueue: virtio_vsock virtio_transport_rx_work [vmw_vsock_virtio_transport]
  RIP: 0010:virtio_transport_send_pkt_info+0x20/0x130 [vmw_vsock_virtio_transport_common]
  Code: 1f 84 00 00 00 00 00 0f 1f 00 55 48 89 e5 41 57 41 56 41 55 49 89 f5 41 54 49 89 fc 53 48 83 ec 10 44 8b 76 20 e8 c0 ba fe ff <48> 8b 80 e8 00 00 00 e8 64 e3 7d c1 45 8b 45 00 41 8b 8c 24 d4 02
  RSP: 0018:ffffc900000b7d08 EFLAGS: 00010282
  RAX: 0000000000000000 RBX: ffff88807bf12728 RCX: 0000000000000000
  RDX: ffff88807bf12700 RSI: ffffc900000b7d50 RDI: ffff888035c84000
  RBP: ffffc900000b7d40 R08: ffff888035c84000 R09: ffffc900000b7d08
  R10: ffff8880781de800 R11: 0000000000000018 R12: ffff888035c84000
  R13: ffffc900000b7d50 R14: 0000000000000000 R15: ffff88807bf12724
  FS:  0000000000000000(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000000000e8 CR3: 00000000790f4004 CR4: 0000000000160ef0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   virtio_transport_reset+0x59/0x70 [vmw_vsock_virtio_transport_common]
   virtio_transport_recv_pkt+0x5bb/0xe50 [vmw_vsock_virtio_transport_common]
   ? detach_buf_split+0xf1/0x130
   virtio_transport_rx_work+0xba/0x130 [vmw_vsock_virtio_transport]
   process_one_work+0x1c0/0x300
   worker_thread+0x45/0x3c0
   kthread+0xfc/0x130
   ? current_work+0x40/0x40
   ? kthread_park+0x90/0x90
   ret_from_fork+0x35/0x40
  Modules linked in: sunrpc kvm_intel kvm vmw_vsock_virtio_transport vmw_vsock_virtio_transport_common irqbypass vsock virtio_rng rng_core
  CR2: 00000000000000e8
  ---[ end trace e75400e2ea2fa824 ]---

This happens because virtio_transport_reset() calls
virtio_transport_send_pkt_info() that can be used only on
connecting/connected sockets.

This patch fixes the issue, using virtio_transport_reset_no_sock()
instead of virtio_transport_reset() when we are handling a listener
socket.

Fixes: c0cfa2d ("vsock: add multi-transports support")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Jan 25, 2021
I was hitting the below panic continuously when attaching kprobes to
scheduler functions

	[  159.045212] Unexpected kernel BRK exception at EL1
	[  159.053753] Internal error: BRK handler: f2000006 [#1] PREEMPT SMP
	[  159.059954] Modules linked in:
	[  159.063025] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.11.0-rc4-00008-g1e2a199f6ccd linux-sunxi#56
	[rt-app] <notice> [1] Exiting.[  159.071166] Hardware name: ARM Juno development board (r2) (DT)
	[  159.079689] pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO BTYPE=--)

	[  159.085723] pc : 0xffff80001624501c
	[  159.089377] lr : attach_entity_load_avg+0x2ac/0x350
	[  159.094271] sp : ffff80001622b640
	[rt-app] <notice> [0] Exiting.[  159.097591] x29: ffff80001622b640 x28: 0000000000000001
	[  159.105515] x27: 0000000000000049 x26: ffff000800b79980

	[  159.110847] x25: ffff00097ef37840 x24: 0000000000000000
	[  159.116331] x23: 00000024eacec1ec x22: ffff00097ef12b90
	[  159.121663] x21: ffff00097ef37700 x20: ffff800010119170
	[rt-app] <notice> [11] Exiting.[  159.126995] x19: ffff00097ef37840 x18: 000000000000000e
	[  159.135003] x17: 0000000000000001 x16: 0000000000000019
	[  159.140335] x15: 0000000000000000 x14: 0000000000000000
	[  159.145666] x13: 0000000000000002 x12: 0000000000000002
	[  159.150996] x11: ffff80001592f9f0 x10: 0000000000000060
	[  159.156327] x9 : ffff8000100f6f9c x8 : be618290de0999a1
	[  159.161659] x7 : ffff80096a4b1000 x6 : 0000000000000000
	[  159.166990] x5 : ffff00097ef37840 x4 : 0000000000000000
	[  159.172321] x3 : ffff000800328948 x2 : 0000000000000000
	[  159.177652] x1 : 0000002507d52fec x0 : ffff00097ef12b90
	[  159.182983] Call trace:
	[  159.185433]  0xffff80001624501c
	[  159.188581]  update_load_avg+0x2d0/0x778
	[  159.192516]  enqueue_task_fair+0x134/0xe20
	[  159.196625]  enqueue_task+0x4c/0x2c8
	[  159.200211]  ttwu_do_activate+0x70/0x138
	[  159.204147]  sched_ttwu_pending+0xbc/0x160
	[  159.208253]  flush_smp_call_function_queue+0x16c/0x320
	[  159.213408]  generic_smp_call_function_single_interrupt+0x1c/0x28
	[  159.219521]  ipi_handler+0x1e8/0x3c8
	[  159.223106]  handle_percpu_devid_irq+0xd8/0x460
	[  159.227650]  generic_handle_irq+0x38/0x50
	[  159.231672]  __handle_domain_irq+0x6c/0xc8
	[  159.235781]  gic_handle_irq+0xcc/0xf0
	[  159.239452]  el1_irq+0xb4/0x180
	[  159.242600]  rcu_is_watching+0x28/0x70
	[  159.246359]  rcu_read_lock_held_common+0x44/0x88
	[  159.250991]  rcu_read_lock_any_held+0x30/0xc0
	[  159.255360]  kretprobe_dispatcher+0xc4/0xf0
	[  159.259555]  __kretprobe_trampoline_handler+0xc0/0x150
	[  159.264710]  trampoline_probe_handler+0x38/0x58
	[  159.269255]  kretprobe_trampoline+0x70/0xc4
	[  159.273450]  run_rebalance_domains+0x54/0x80
	[  159.277734]  __do_softirq+0x164/0x684
	[  159.281406]  irq_exit+0x198/0x1b8
	[  159.284731]  __handle_domain_irq+0x70/0xc8
	[  159.288840]  gic_handle_irq+0xb0/0xf0
	[  159.292510]  el1_irq+0xb4/0x180
	[  159.295658]  arch_cpu_idle+0x18/0x28
	[  159.299245]  default_idle_call+0x9c/0x3e8
	[  159.303265]  do_idle+0x25c/0x2a8
	[  159.306502]  cpu_startup_entry+0x2c/0x78
	[  159.310436]  secondary_start_kernel+0x160/0x198
	[  159.314984] Code: d42000c0 aa1e03e9 d42000c0 aa1e03e9 (d42000c0)

After a bit of head scratching and debugging it turned out that it is
due to kprobe handler being interrupted by a tick that causes us to go
into (I think another) kprobe handler.

The culprit was kprobe_breakpoint_ss_handler() returning DBG_HOOK_ERROR
which leads to the Unexpected kernel BRK exception.

Reverting commit ba090f9 ("arm64: kprobes: Remove redundant
kprobe_step_ctx") seemed to fix the problem for me.

Further analysis showed that kcb->kprobe_status is set to
KPROBE_REENTER when the error occurs. By teaching
kprobe_breakpoint_ss_handler() to handle this status I can no  longer
reproduce the problem.

Fixes: ba090f9 ("arm64: kprobes: Remove redundant kprobe_step_ctx")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20210122110909.3324607-1-qais.yousef@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Mar 23, 2023
[ Upstream commit 9ca5e7e ]

When a file descriptor of pppol2tp socket is passed as file descriptor
of UDP socket, a recursive deadlock occurs in l2tp_tunnel_register().
This situation is reproduced by the following program:

int main(void)
{
	int sock;
	struct sockaddr_pppol2tp addr;

	sock = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP);
	if (sock < 0) {
		perror("socket");
		return 1;
	}

	addr.sa_family = AF_PPPOX;
	addr.sa_protocol = PX_PROTO_OL2TP;
	addr.pppol2tp.pid = 0;
	addr.pppol2tp.fd = sock;
	addr.pppol2tp.addr.sin_family = PF_INET;
	addr.pppol2tp.addr.sin_port = htons(0);
	addr.pppol2tp.addr.sin_addr.s_addr = inet_addr("192.168.0.1");
	addr.pppol2tp.s_tunnel = 1;
	addr.pppol2tp.s_session = 0;
	addr.pppol2tp.d_tunnel = 0;
	addr.pppol2tp.d_session = 0;

	if (connect(sock, (const struct sockaddr *)&addr, sizeof(addr)) < 0) {
		perror("connect");
		return 1;
	}

	return 0;
}

This program causes the following lockdep warning:

 ============================================
 WARNING: possible recursive locking detected
 6.2.0-rc5-00205-gc96618275234 linux-sunxi#56 Not tainted
 --------------------------------------------
 repro/8607 is trying to acquire lock:
 ffff8880213c8130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: l2tp_tunnel_register+0x2b7/0x11c0

 but task is already holding lock:
 ffff8880213c8130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0xa82/0x1a30

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(sk_lock-AF_PPPOX);
   lock(sk_lock-AF_PPPOX);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 1 lock held by repro/8607:
  #0: ffff8880213c8130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0xa82/0x1a30

 stack backtrace:
 CPU: 0 PID: 8607 Comm: repro Not tainted 6.2.0-rc5-00205-gc96618275234 linux-sunxi#56
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x100/0x178
  __lock_acquire.cold+0x119/0x3b9
  ? lockdep_hardirqs_on_prepare+0x410/0x410
  lock_acquire+0x1e0/0x610
  ? l2tp_tunnel_register+0x2b7/0x11c0
  ? lock_downgrade+0x710/0x710
  ? __fget_files+0x283/0x3e0
  lock_sock_nested+0x3a/0xf0
  ? l2tp_tunnel_register+0x2b7/0x11c0
  l2tp_tunnel_register+0x2b7/0x11c0
  ? sprintf+0xc4/0x100
  ? l2tp_tunnel_del_work+0x6b0/0x6b0
  ? debug_object_deactivate+0x320/0x320
  ? lockdep_init_map_type+0x16d/0x7a0
  ? lockdep_init_map_type+0x16d/0x7a0
  ? l2tp_tunnel_create+0x2bf/0x4b0
  ? l2tp_tunnel_create+0x3c6/0x4b0
  pppol2tp_connect+0x14e1/0x1a30
  ? pppol2tp_put_sk+0xd0/0xd0
  ? aa_sk_perm+0x2b7/0xa80
  ? aa_af_perm+0x260/0x260
  ? bpf_lsm_socket_connect+0x9/0x10
  ? pppol2tp_put_sk+0xd0/0xd0
  __sys_connect_file+0x14f/0x190
  __sys_connect+0x133/0x160
  ? __sys_connect_file+0x190/0x190
  ? lockdep_hardirqs_on+0x7d/0x100
  ? ktime_get_coarse_real_ts64+0x1b7/0x200
  ? ktime_get_coarse_real_ts64+0x147/0x200
  ? __audit_syscall_entry+0x396/0x500
  __x64_sys_connect+0x72/0xb0
  do_syscall_64+0x38/0xb0
  entry_SYSCALL_64_after_hwframe+0x63/0xcd

This patch fixes the issue by getting/creating the tunnel before
locking the pppol2tp socket.

Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()")
Cc: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Oct 25, 2023
…ress

If we specify a valid CQ ring address but an invalid SQ ring address,
we'll correctly spot this and free the allocated pages and clear them
to NULL. However, we don't clear the ring page count, and hence will
attempt to free the pages again. We've already cleared the address of
the page array when freeing them, but we don't check for that. This
causes the following crash:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Oops [#1]
Modules linked in:
CPU: 0 PID: 20 Comm: kworker/u2:1 Not tainted 6.6.0-rc5-dirty linux-sunxi#56
Hardware name: ucbbar,riscvemu-bare (DT)
Workqueue: events_unbound io_ring_exit_work
epc : io_pages_free+0x2a/0x58
 ra : io_rings_free+0x3a/0x50
 epc : ffffffff808811a2 ra : ffffffff80881406 sp : ffff8f80000c3cd0
 status: 0000000200000121 badaddr: 0000000000000000 cause: 000000000000000d
 [<ffffffff808811a2>] io_pages_free+0x2a/0x58
 [<ffffffff80881406>] io_rings_free+0x3a/0x50
 [<ffffffff80882176>] io_ring_exit_work+0x37e/0x424
 [<ffffffff80027234>] process_one_work+0x10c/0x1f4
 [<ffffffff8002756e>] worker_thread+0x252/0x31c
 [<ffffffff8002f5e4>] kthread+0xc4/0xe0
 [<ffffffff8000332a>] ret_from_fork+0xa/0x1c

Check for a NULL array in io_pages_free(), but also clear the page counts
when we free them to be on the safer side.

Reported-by: rtm@csail.mit.edu
Fixes: 03d89a2 ("io_uring: support for user allocated memory for rings/sqes")
Cc: stable@vger.kernel.org
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Sep 6, 2024
[ Upstream commit 26afda7 ]

Christoph reported the following splat:

WARNING: CPU: 1 PID: 772 at net/ipv4/af_inet.c:761 __inet_accept+0x1f4/0x4a0
Modules linked in:
CPU: 1 PID: 772 Comm: syz-executor510 Not tainted 6.9.0-rc7-g7da7119fe22b linux-sunxi#56
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
RIP: 0010:__inet_accept+0x1f4/0x4a0 net/ipv4/af_inet.c:759
Code: 04 38 84 c0 0f 85 87 00 00 00 41 c7 04 24 03 00 00 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 ec b7 da fd <0f> 0b e9 7f fe ff ff e8 e0 b7 da fd 0f 0b e9 fe fe ff ff 89 d9 80
RSP: 0018:ffffc90000c2fc58 EFLAGS: 00010293
RAX: ffffffff836bdd14 RBX: 0000000000000000 RCX: ffff888104668000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff836bdb89 R09: fffff52000185f64
R10: dffffc0000000000 R11: fffff52000185f64 R12: dffffc0000000000
R13: 1ffff92000185f98 R14: ffff88810754d880 R15: ffff8881007b7800
FS:  000000001c772880(0000) GS:ffff88811b280000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb9fcf2e178 CR3: 00000001045d2002 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 inet_accept+0x138/0x1d0 net/ipv4/af_inet.c:786
 do_accept+0x435/0x620 net/socket.c:1929
 __sys_accept4_file net/socket.c:1969 [inline]
 __sys_accept4+0x9b/0x110 net/socket.c:1999
 __do_sys_accept net/socket.c:2016 [inline]
 __se_sys_accept net/socket.c:2013 [inline]
 __x64_sys_accept+0x7d/0x90 net/socket.c:2013
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0x100 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x4315f9
Code: fd ff 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 ab b4 fd ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdb26d9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002b
RAX: ffffffffffffffda RBX: 0000000000400300 RCX: 00000000004315f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00000000006e1018 R08: 0000000000400300 R09: 0000000000400300
R10: 0000000000400300 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000040cdf0 R14: 000000000040ce80 R15: 0000000000000055
 </TASK>

The reproducer invokes shutdown() before entering the listener status.
After commit 9406279 ("tcp: defer shutdown(SEND_SHUTDOWN) for
TCP_SYN_RECV sockets"), the above causes the child to reach the accept
syscall in FIN_WAIT1 status.

Eric noted we can relax the existing assertion in __inet_accept()

Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: multipath-tcp/mptcp_net-next#490
Suggested-by: Eric Dumazet <edumazet@google.com>
Fixes: 9406279 ("tcp: defer shutdown(SEND_SHUTDOWN) for TCP_SYN_RECV sockets")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/23ab880a44d8cfd967e84de8b93dbf48848e3d8c.1716299669.git.pabeni@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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