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rename properties like DRM_I915_PERF_PROP_foo #11

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rib opened this issue Feb 4, 2016 · 0 comments
Closed

rename properties like DRM_I915_PERF_PROP_foo #11

rib opened this issue Feb 4, 2016 · 0 comments

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rib commented Feb 4, 2016

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rib pushed a commit that referenced this issue Feb 22, 2016
Fixes segmentation fault using, for instance:

  (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".

 Program received signal SIGSEGV, Segmentation fault.
  0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  (gdb) bt
  #0  0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  #1  0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:433
  #2  0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:498
  #3  0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:936
  #4  0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391
  #5  0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361
  #6  0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401
  #7  0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253
  #8  0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364
  #9  0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664
  #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539
  #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264
  #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390
  #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451
  #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495
  #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618
(gdb)

Intel PT attempts to find the sched:sched_switch tracepoint but that seg
faults if tracefs is not readable, because the error reporting structure
is null, as errors are not reported when automatically adding
tracepoints.  Fix by checking before using.

Committer note:

This doesn't take place in a kernel that supports
perf_event_attr.context_switch, that is the default way that will be
used for tracking context switches, only in older kernels, like 4.2, in
a machine with Intel PT (e.g. Broadwell) for non-priviledged users.

Further info from a similar patch by Wang:

The error is in tracepoint_error: it assumes the 'e' parameter is valid.

However, there are many situation a parse_event() can be called without
parse_events_error. See result of

  $ grep 'parse_events(.*NULL)' ./tools/perf/ -r'

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Tong Zhang <ztong@vt.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output")
Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
@rib rib closed this as completed Mar 24, 2016
matt-auld pushed a commit to matt-auld/linux that referenced this issue Apr 26, 2016
Adding a 2nd PHY to cpsw results in a NULL pointer dereference
as below. Fix by maintaining a reference to each PHY node in slave
struct instead of a single reference in the priv struct which was
overwritten by the 2nd PHY.

[   17.870933] Unable to handle kernel NULL pointer dereference at virtual address 00000180
[   17.879557] pgd = dc8bc000
[   17.882514] [00000180] *pgd=9c882831, *pte=00000000, *ppte=00000000
[   17.889213] Internal error: Oops: 17 [rib#1] ARM
[   17.893838] Modules linked in:
[   17.897102] CPU: 0 PID: 1657 Comm: connmand Not tainted 4.5.0-ge463dfb-dirty rib#11
[   17.904947] Hardware name: Cambrionix whippet
[   17.909576] task: dc859240 ti: dc968000 task.ti: dc968000
[   17.915339] PC is at phy_attached_print+0x18/0x8c
[   17.920339] LR is at phy_attached_info+0x14/0x18
[   17.925247] pc : [<c042baec>]    lr : [<c042bb74>]    psr: 600f0113
[   17.925247] sp : dc969cf8  ip : dc969d28  fp : dc969d18
[   17.937425] r10: dda7a400  r9 : 00000000  r8 : 00000000
[   17.942971] r7 : 00000001  r6 : ddb00480  r5 : ddb8cb34  r4 : 00000000
[   17.949898] r3 : c0954cc0  r2 : c09562b0  r1 : 00000000  r0 : 00000000
[   17.956829] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[   17.964401] Control: 10c5387d  Table: 9c8bc019  DAC: 00000051
[   17.970500] Process connmand (pid: 1657, stack limit = 0xdc968210)
[   17.977059] Stack: (0xdc969cf8 to 0xdc96a000)
[   17.981692] 9ce0:                                                       dc969d28 dc969d08
[   17.990386] 9d00: c038f9bc c038f6b4 ddb00480 dc969d34 dc969d28 c042bb74 c042bae4 00000000
[   17.999080] 9d20: c09562b0 c0954cc0 dc969d5c dc969d38 c043ebfc c042bb6c 00000007 00000003
[   18.007773] 9d40: ddb00000 ddb8cb58 ddb00480 00000001 dc969dec dc969d60 c0441614 c043ea68
[   18.016465] 9d60: 00000000 00000003 00000000 fffffff4 dc969df4 0000000d 00000000 00000000
[   18.025159] 9d80: dc969db4 dc969d90 c005dc08 c05839e0 dc969df4 0000000d ddb00000 00001002
[   18.033851] 9da0: 00000000 00000000 dc969dcc dc969db8 c005ddf4 c005dbc8 00000000 00000118
[   18.042544] 9dc0: dc969dec dc969dd0 ddb00000 c06db27c ffff9003 00001002 00000000 00000000
[   18.051237] 9de0: dc969e0c dc969df0 c057c88c c04410dc dc969e0c ddb00000 ddb00000 00000001
[   18.059930] 9e00: dc969e34 dc969e10 c057cb44 c057c7d8 ddb00000 ddb00138 00001002 beaeda20
[   18.068622] 9e20: 00000000 00000000 dc969e5c dc969e38 c057cc28 c057cac0 00000000 dc969e80
[   18.077315] 9e40: dda7a40c beaeda20 00000000 00000000 dc969ecc dc969e60 c05e36d0 c057cc14
[   18.086007] 9e60: dc969e84 00000051 beaeda20 00000000 dda7a40c 00000014 ddb00000 00008914
[   18.094699] 9e80: 30687465 00000000 00000000 00000000 00009003 00000000 00000000 00000000
[   18.103391] 9ea0: 00001002 00008914 dd257ae0 beaeda20 c098a428 beaeda20 00000011 00000000
[   18.112084] 9ec0: dc969edc dc969ed0 c05e4e54 c05e3030 dc969efc dc969ee0 c055f5ac c05e4cc4
[   18.120777] 9ee0: beaeda20 dd257ae0 dc8ab4c0 00008914 dc969f7c dc969f00 c010b388 c055f45c
[   18.129471] 9f00: c071ca40 dd257ac0 c00165e8 dc968000 dc969f3c dc969f20 dc969f64 dc969f28
[   18.138164] 9f20: c0115708 c0683ec8 dd257ac0 dd257ac0 dc969f74 dc969f40 c055f350 c00fc66c
[   18.146857] 9f40: dd82e4d0 00000011 00000000 00080000 dd257ac0 00000000 dc8ab4c0 dc8ab4c0
[   18.155550] 9f60: 00008914 beaeda20 00000011 00000000 dc969fa4 dc969f80 c010bc34 c010b2fc
[   18.164242] 9f80: 00000000 00000011 00000002 00000036 c00165e8 dc968000 00000000 dc969fa8
[   18.172935] 9fa0: c00163e0 c010bbcc 00000000 00000011 00000011 00008914 beaeda20 00009003
[   18.181628] 9fc0: 00000000 00000011 00000002 00000036 00081018 00000001 00000000 beaedc10
[   18.190320] 9fe0: 00083188 beaeda1c 00043a5d b6d29c0c 600b0010 00000011 00000000 00000000
[   18.198989] Backtrace:
[   18.201621] [<c042bad8>] (phy_attached_print) from [<c042bb74>] (phy_attached_info+0x14/0x18)
[   18.210664]  r3:c0954cc0 r2:c09562b0 r1:00000000
[   18.215588]  r4:ddb00480
[   18.218322] [<c042bb60>] (phy_attached_info) from [<c043ebfc>] (cpsw_slave_open+0x1a0/0x280)
[   18.227293] [<c043ea5c>] (cpsw_slave_open) from [<c0441614>] (cpsw_ndo_open+0x544/0x674)
[   18.235874]  r7:00000001 r6:ddb00480 r5:ddb8cb58 r4:ddb00000
[   18.241944] [<c04410d0>] (cpsw_ndo_open) from [<c057c88c>] (__dev_open+0xc0/0x128)
[   18.249972]  r9:00000000 r8:00000000 r7:00001002 r6:ffff9003 r5:c06db27c r4:ddb00000
[   18.258255] [<c057c7cc>] (__dev_open) from [<c057cb44>] (__dev_change_flags+0x90/0x154)
[   18.266745]  r5:00000001 r4:ddb00000
[   18.270575] [<c057cab4>] (__dev_change_flags) from [<c057cc28>] (dev_change_flags+0x20/0x50)
[   18.279523]  r9:00000000 r8:00000000 r7:beaeda20 r6:00001002 r5:ddb00138 r4:ddb00000
[   18.287811] [<c057cc08>] (dev_change_flags) from [<c05e36d0>] (devinet_ioctl+0x6ac/0x76c)
[   18.296483]  r9:00000000 r8:00000000 r7:beaeda20 r6:dda7a40c r5:dc969e80 r4:00000000
[   18.304762] [<c05e3024>] (devinet_ioctl) from [<c05e4e54>] (inet_ioctl+0x19c/0x1c8)
[   18.312882]  r10:00000000 r9:00000011 r8:beaeda20 r7:c098a428 r6:beaeda20 r5:dd257ae0
[   18.321235]  r4:00008914
[   18.323956] [<c05e4cb8>] (inet_ioctl) from [<c055f5ac>] (sock_ioctl+0x15c/0x2d8)
[   18.331829] [<c055f450>] (sock_ioctl) from [<c010b388>] (do_vfs_ioctl+0x98/0x8d0)
[   18.339765]  r7:00008914 r6:dc8ab4c0 r5:dd257ae0 r4:beaeda20
[   18.345822] [<c010b2f0>] (do_vfs_ioctl) from [<c010bc34>] (SyS_ioctl+0x74/0x84)
[   18.353573]  r10:00000000 r9:00000011 r8:beaeda20 r7:00008914 r6:dc8ab4c0 r5:dc8ab4c0
[   18.361924]  r4:00000000
[   18.364653] [<c010bbc0>] (SyS_ioctl) from [<c00163e0>] (ret_fast_syscall+0x0/0x3c)
[   18.372682]  r9:dc968000 r8:c00165e8 r7:00000036 r6:00000002 r5:00000011 r4:00000000
[   18.380960] Code: e92dd810 e24cb010 e24dd010 e59b4004 (e5902180)
[   18.387580] ---[ end trace c80529466223f3f3 ]---

Signed-off-by: Andrew Goodbody <andrew.goodbody@cambrionix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Sep 16, 2016
When a seq-virmidi driver is initialized, it registers a rawmidi
instance with its callback to create an associated seq kernel client.
Currently it's done throughly in rawmidi's register_mutex context.
Recently it was found that this may lead to a deadlock another rawmidi
device that is being attached with the sequencer is accessed, as both
open with the same register_mutex.  This was actually triggered by
syzkaller, as Dmitry Vyukov reported:

======================================================
 [ INFO: possible circular locking dependency detected ]
 4.8.0-rc1+ rib#11 Not tainted
 -------------------------------------------------------
 syz-executor/7154 is trying to acquire lock:
  (register_mutex#5){+.+.+.}, at: [<ffffffff84fd6d4b>] snd_rawmidi_kernel_open+0x4b/0x260 sound/core/rawmidi.c:341

 but task is already holding lock:
  (&grp->list_mutex){++++.+}, at: [<ffffffff850138bb>] check_and_subscribe_port+0x5b/0x5c0 sound/core/seq/seq_ports.c:495

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> rib#1 (&grp->list_mutex){++++.+}:
    [<ffffffff8147a3a8>] lock_acquire+0x208/0x430 kernel/locking/lockdep.c:3746
    [<ffffffff863f6199>] down_read+0x49/0xc0 kernel/locking/rwsem.c:22
    [<     inline     >] deliver_to_subscribers sound/core/seq/seq_clientmgr.c:681
    [<ffffffff85005c5e>] snd_seq_deliver_event+0x35e/0x890 sound/core/seq/seq_clientmgr.c:822
    [<ffffffff85006e96>] > snd_seq_kernel_client_dispatch+0x126/0x170 sound/core/seq/seq_clientmgr.c:2418
    [<ffffffff85012c52>] snd_seq_system_broadcast+0xb2/0xf0 sound/core/seq/seq_system.c:101
    [<ffffffff84fff70a>] snd_seq_create_kernel_client+0x24a/0x330 sound/core/seq/seq_clientmgr.c:2297
    [<     inline     >] snd_virmidi_dev_attach_seq sound/core/seq/seq_virmidi.c:383
    [<ffffffff8502d29f>] snd_virmidi_dev_register+0x29f/0x750 sound/core/seq/seq_virmidi.c:450
    [<ffffffff84fd208c>] snd_rawmidi_dev_register+0x30c/0xd40 sound/core/rawmidi.c:1645
    [<ffffffff84f816d3>] __snd_device_register.part.0+0x63/0xc0 sound/core/device.c:164
    [<     inline     >] __snd_device_register sound/core/device.c:162
    [<ffffffff84f8235d>] snd_device_register_all+0xad/0x110 sound/core/device.c:212
    [<ffffffff84f7546f>] snd_card_register+0xef/0x6c0 sound/core/init.c:749
    [<ffffffff85040b7f>] snd_virmidi_probe+0x3ef/0x590 sound/drivers/virmidi.c:123
    [<ffffffff833ebf7b>] platform_drv_probe+0x8b/0x170 drivers/base/platform.c:564
    ......

 -> #0 (register_mutex#5){+.+.+.}:
    [<     inline     >] check_prev_add kernel/locking/lockdep.c:1829
    [<     inline     >] check_prevs_add kernel/locking/lockdep.c:1939
    [<     inline     >] validate_chain kernel/locking/lockdep.c:2266
    [<ffffffff814791f4>] __lock_acquire+0x4d44/0x4d80 kernel/locking/lockdep.c:3335
    [<ffffffff8147a3a8>] lock_acquire+0x208/0x430 kernel/locking/lockdep.c:3746
    [<     inline     >] __mutex_lock_common kernel/locking/mutex.c:521
    [<ffffffff863f0ef1>] mutex_lock_nested+0xb1/0xa20 kernel/locking/mutex.c:621
    [<ffffffff84fd6d4b>] snd_rawmidi_kernel_open+0x4b/0x260 sound/core/rawmidi.c:341
    [<ffffffff8502e7c7>] midisynth_subscribe+0xf7/0x350 sound/core/seq/seq_midi.c:188
    [<     inline     >] subscribe_port sound/core/seq/seq_ports.c:427
    [<ffffffff85013cc7>] check_and_subscribe_port+0x467/0x5c0 sound/core/seq/seq_ports.c:510
    [<ffffffff85015da9>] snd_seq_port_connect+0x2c9/0x500 sound/core/seq/seq_ports.c:579
    [<ffffffff850079b8>] snd_seq_ioctl_subscribe_port+0x1d8/0x2b0 sound/core/seq/seq_clientmgr.c:1480
    [<ffffffff84ffe9e4>] snd_seq_do_ioctl+0x184/0x1e0 sound/core/seq/seq_clientmgr.c:2225
    [<ffffffff84ffeae8>] snd_seq_kernel_client_ctl+0xa8/0x110 sound/core/seq/seq_clientmgr.c:2440
    [<ffffffff85027664>] snd_seq_oss_midi_open+0x3b4/0x610 sound/core/seq/oss/seq_oss_midi.c:375
    [<ffffffff85023d67>] snd_seq_oss_synth_setup_midi+0x107/0x4c0 sound/core/seq/oss/seq_oss_synth.c:281
    [<ffffffff8501b0a8>] snd_seq_oss_open+0x748/0x8d0 sound/core/seq/oss/seq_oss_init.c:274
    [<ffffffff85019d8a>] odev_open+0x6a/0x90 sound/core/seq/oss/seq_oss.c:138
    [<ffffffff84f7040f>] soundcore_open+0x30f/0x640 sound/sound_core.c:639
    ......

 other info that might help us debug this:

 Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&grp->list_mutex);
                                lock(register_mutex#5);
                                lock(&grp->list_mutex);
   lock(register_mutex#5);

 *** DEADLOCK ***
======================================================

The fix is to simply move the registration parts in
snd_rawmidi_dev_register() to the outside of the register_mutex lock.
The lock is needed only to manage the linked list, and it's not
necessarily to cover the whole initialization process.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
rib pushed a commit that referenced this issue Feb 13, 2017
[12493.693827] WARNING: CPU: 1 PID: 14860 at drivers/gpu/drm/i915/intel_uncore.c:795 __unclaimed_reg_debug+0x5d/0x80 [i915]
[12493.693868] Unclaimed read from register 0x1f0024
[12493.693905] Modules linked in: vgem i915 drm_kms_helper drm intel_gtt i2c_algo_bit syscopyarea sysfillrect sysimgblt fb_sys_fops prime_numbers intel_powerclamp crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel cryptd lpc_ich i2c_i801 mfd_core video i2c_designware_platform i2c_designware_core i2c_core button autofs4 sd_mod ahci libahci libata scsi_mod [last unloaded: i915]
[12493.694039] CPU: 1 PID: 14860 Comm: intel-gpu-overl Tainted: G     U          4.10.0-rc7+ #11
[12493.694079] Hardware name: GIGABYTE GB-BXBT-1900/MZBAYAB-00, BIOS F8 03/02/2016
[12493.694121] Call Trace:
[12493.694169]  dump_stack+0x67/0x9d
[12493.694235]  __warn+0x117/0x140
[12493.694288]  warn_slowpath_fmt+0x4f/0x60
[12493.694344]  ? do_raw_spin_lock+0x116/0x180
[12493.694533]  ? check_for_unclaimed_mmio+0x98/0xe0 [i915]
[12493.694727]  __unclaimed_reg_debug+0x5d/0x80 [i915]
[12493.694923]  fwtable_read32+0x2c5/0x330 [i915]
[12493.695108]  i915_interrupt_info+0xd52/0xf80 [i915]
[12493.695302]  ? gen6_write16+0x310/0x310 [i915]
[12493.695357]  seq_read+0x187/0x710
[12493.695412]  full_proxy_read+0x75/0xc0
[12493.695472]  __vfs_read+0x5a/0x220
[12493.695524]  ? kmem_cache_free+0x6c/0x260
[12493.695577]  ? putname+0x97/0xa0
[12493.695629]  ? putname+0x97/0xa0
[12493.695682]  ? rcu_read_lock_sched_held+0xb8/0xd0
[12493.695735]  ? rw_verify_area+0x65/0x140
[12493.695787]  vfs_read+0xd1/0x1f0
[12493.695840]  SyS_read+0x62/0xc0
[12493.695893]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[12493.695943] RIP: 0033:0x7f82dca99ba0
[12493.695985] RSP: 002b:00007ffc0bdfd4f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[12493.696031] RAX: ffffffffffffffda RBX: 00007ffc0be005a0 RCX: 00007f82dca99ba0
[12493.696073] RDX: 0000000000001fff RSI: 00007ffc0bdfd500 RDI: 000000000000001a
[12493.696115] RBP: ffffffff810fb639 R08: 302f6972642f6775 R09: 00007f82dca0999a
[12493.696157] R10: 00007f82dcd62760 R11: 0000000000000246 R12: ffff880069a17f98
[12493.696199] R13: 00007ffc0bdfd428 R14: 0000000000000003 R15: 00007ffc0bdfd428
[12493.696250]  ? trace_hardirqs_off_caller+0xd9/0x130
[12493.696300] ---[ end trace 52ccf4d39793cc59 ]---

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99761
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210133632.16946-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 8, 2017
nla_memdup_cookie was overwriting err value, declared at function
scope and earlier initialized with result of ->init(). At success
nla_memdup_cookie() returns 0, and thus module refcnt decremented,
although the action was installed.

$ sudo tc actions add action pass index 1 cookie 1234
$ sudo tc actions ls action gact

        action order 0: gact action pass
         random type none pass val 0
         index 1 ref 1 bind 0
$
$ lsmod
Module                  Size  Used by
act_gact               16384  0
...
$
$ sudo rmmod act_gact
[   52.310283] ------------[ cut here ]------------
[   52.312551] WARNING: CPU: 1 PID: 455 at kernel/module.c:1113
module_put+0x99/0xa0
[   52.316278] Modules linked in: act_gact(-) crct10dif_pclmul crc32_pclmul
ghash_clmulni_intel psmouse pcbc evbug aesni_intel aes_x86_64 crypto_simd
serio_raw glue_helper pcspkr cryptd
[   52.322285] CPU: 1 PID: 455 Comm: rmmod Not tainted 4.10.0+ rib#11
[   52.324261] Call Trace:
[   52.325132]  dump_stack+0x63/0x87
[   52.326236]  __warn+0xd1/0xf0
[   52.326260]  warn_slowpath_null+0x1d/0x20
[   52.326260]  module_put+0x99/0xa0
[   52.326260]  tcf_hashinfo_destroy+0x7f/0x90
[   52.326260]  gact_exit_net+0x27/0x40 [act_gact]
[   52.326260]  ops_exit_list.isra.6+0x38/0x60
[   52.326260]  unregister_pernet_operations+0x90/0xe0
[   52.326260]  unregister_pernet_subsys+0x21/0x30
[   52.326260]  tcf_unregister_action+0x68/0xa0
[   52.326260]  gact_cleanup_module+0x17/0xa0f [act_gact]
[   52.326260]  SyS_delete_module+0x1ba/0x220
[   52.326260]  entry_SYSCALL_64_fastpath+0x1e/0xad
[   52.326260] RIP: 0033:0x7f527ffae367
[   52.326260] RSP: 002b:00007ffeb402a598 EFLAGS: 00000202 ORIG_RAX:
00000000000000b0
[   52.326260] RAX: ffffffffffffffda RBX: 0000559b069912a0 RCX: 00007f527ffae367
[   52.326260] RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559b06991308
[   52.326260] RBP: 0000000000000003 R08: 00007f5280264420 R09: 00007ffeb4029511
[   52.326260] R10: 000000000000087b R11: 0000000000000202 R12: 00007ffeb4029580
[   52.326260] R13: 0000000000000000 R14: 0000000000000000 R15: 0000559b069912a0
[   52.354856] ---[ end trace 90d89401542b0db6 ]---
$

With the fix:

$ sudo modprobe act_gact
$ lsmod
Module                  Size  Used by
act_gact               16384  0
...
$ sudo tc actions add action pass index 1 cookie 1234
$ sudo tc actions ls action gact

        action order 0: gact action pass
         random type none pass val 0
         index 1 ref 1 bind 0
$
$ lsmod
Module                  Size  Used by
act_gact               16384  1
...
$ sudo rmmod act_gact
rmmod: ERROR: Module act_gact is in use
$
$ sudo /home/mrv/bin/tc actions del action gact index 1
$ sudo rmmod act_gact
$ lsmod
Module                  Size  Used by
$

Fixes: 1045ba7 ("net sched actions: Add support for user cookies")
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rib pushed a commit that referenced this issue Mar 23, 2017
As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.

We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:

 #8 [] page_fault at ffffffff8163e648
    [exception RIP: __tcp_ack_snd_check+74]
.
.
 #9 [] tcp_rcv_established at ffffffff81580b64
#10 [] tcp_v4_do_rcv at ffffffff8158b54a
#11 [] tcp_v4_rcv at ffffffff8158cd02
#12 [] ip_local_deliver_finish at ffffffff815668f4
#13 [] ip_local_deliver at ffffffff81566bd9
#14 [] ip_rcv_finish at ffffffff8156656d
#15 [] ip_rcv at ffffffff81566f06
#16 [] __netif_receive_skb_core at ffffffff8152b3a2
#17 [] __netif_receive_skb at ffffffff8152b608
#18 [] netif_receive_skb at ffffffff8152b690
#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
#21 [] net_rx_action at ffffffff8152bac2
#22 [] __do_softirq at ffffffff81084b4f
#23 [] call_softirq at ffffffff8164845c
#24 [] do_softirq at ffffffff81016fc5
#25 [] irq_exit at ffffffff81084ee5
torvalds#26 [] do_IRQ at ffffffff81648ff8

Of course it may happen with other NIC drivers as well.

It's found the freed dst_entry here:

 224 static bool tcp_in_quickack_mode(struct sock *sk)↩
 225 {↩
 226 ▹       const struct inet_connection_sock *icsk = inet_csk(sk);↩
 227 ▹       const struct dst_entry *dst = __sk_dst_get(sk);↩
 228 ↩
 229 ▹       return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
 230 ▹       ▹       (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
 231 }↩

But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.

All the vmcores showed 2 significant clues:

- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.

- All vmcores showed a postitive LockDroppedIcmps value, e.g:

LockDroppedIcmps                  267

A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:

do_redirect()->__sk_dst_check()-> dst_release().

Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.

To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.

The dccp/IPv6 code is very similar in this respect, so fixing it there too.

As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().

Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
djdeath pushed a commit to djdeath/linux that referenced this issue Apr 26, 2017
commit 4dfce57 upstream.

There have been several reports over the years of NULL pointer
dereferences in xfs_trans_log_inode during xfs_fsr processes,
when the process is doing an fput and tearing down extents
on the temporary inode, something like:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
PID: 29439  TASK: ffff880550584fa0  CPU: 6   COMMAND: "xfs_fsr"
    [exception RIP: xfs_trans_log_inode+0x10]
 rib#9 [ffff8800a57bbbe0] xfs_bunmapi at ffffffffa037398e [xfs]
rib#10 [ffff8800a57bbce8] xfs_itruncate_extents at ffffffffa0391b29 [xfs]
rib#11 [ffff8800a57bbd88] xfs_inactive_truncate at ffffffffa0391d0c [xfs]
rib#12 [ffff8800a57bbdb8] xfs_inactive at ffffffffa0392508 [xfs]
rib#13 [ffff8800a57bbdd8] xfs_fs_evict_inode at ffffffffa035907e [xfs]
rib#14 [ffff8800a57bbe00] evict at ffffffff811e1b67
rib#15 [ffff8800a57bbe28] iput at ffffffff811e23a5
rib#16 [ffff8800a57bbe58] dentry_kill at ffffffff811dcfc8
rib#17 [ffff8800a57bbe88] dput at ffffffff811dd06c
rib#18 [ffff8800a57bbea8] __fput at ffffffff811c823b
rib#19 [ffff8800a57bbef0] ____fput at ffffffff811c846e
rib#20 [ffff8800a57bbf00] task_work_run at ffffffff81093b27
rib#21 [ffff8800a57bbf30] do_notify_resume at ffffffff81013b0c
rib#22 [ffff8800a57bbf50] int_signal at ffffffff8161405d

As it turns out, this is because the i_itemp pointer, along
with the d_ops pointer, has been overwritten with zeros
when we tear down the extents during truncate.  When the in-core
inode fork on the temporary inode used by xfs_fsr was originally
set up during the extent swap, we mistakenly looked at di_nextents
to determine whether all extents fit inline, but this misses extents
generated by speculative preallocation; we should be using if_bytes
instead.

This mistake corrupts the in-memory inode, and code in
xfs_iext_remove_inline eventually gets bad inputs, causing
it to memmove and memset incorrect ranges; this became apparent
because the two values in ifp->if_u2.if_inline_ext[1] contained
what should have been in d_ops and i_itemp; they were memmoved due
to incorrect array indexing and then the original locations
were zeroed with memset, again due to an array overrun.

Fix this by properly using i_df.if_bytes to determine the number
of extents, not di_nextents.

Thanks to dchinner for looking at this with me and spotting the
root cause.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
djdeath pushed a commit to djdeath/linux that referenced this issue Apr 26, 2017
commit d1f1c0e upstream.

Starting with commit d94a461 ("ath9k: use ieee80211_tx_status_noskb
where possible") the driver uses rcu_read_lock() && rcu_read_unlock(), yet on
returning early in ath_tx_edma_tasklet() the unlock is missing leading to stalls
and suspicious RCU usage:

 ===============================
 [ INFO: suspicious RCU usage. ]
 4.9.0-rc8 rib#11 Not tainted
 -------------------------------
 kernel/rcu/tree.c:705 Illegal idle entry in RCU read-side critical section.!

 other info that might help us debug this:

 RCU used illegally from idle CPU!
 rcu_scheduler_active = 1, debug_locks = 0
 RCU used illegally from extended quiescent state!
 1 lock held by swapper/7/0:
 #0:
  (
 rcu_read_lock
 ){......}
 , at:
 [<ffffffffa06ed110>] ath_tx_edma_tasklet+0x0/0x450 [ath9k]

 stack backtrace:
 CPU: 7 PID: 0 Comm: swapper/7 Not tainted 4.9.0-rc8 rib#11
 Hardware name: Acer Aspire V3-571G/VA50_HC_CR, BIOS V2.21 12/16/2013
  ffff88025efc3f38 ffffffff8132b1e5 ffff88017ede4540 0000000000000001
  ffff88025efc3f68 ffffffff810a25f7 ffff88025efcee60 ffff88017edebdd8
  ffff88025eeb5400 0000000000000091 ffff88025efc3f88 ffffffff810c3cd4
 Call Trace:
  <IRQ>
  [<ffffffff8132b1e5>] dump_stack+0x68/0x93
  [<ffffffff810a25f7>] lockdep_rcu_suspicious+0xd7/0x110
  [<ffffffff810c3cd4>] rcu_eqs_enter_common.constprop.85+0x154/0x200
  [<ffffffff810c5a54>] rcu_irq_exit+0x44/0xa0
  [<ffffffff81058631>] irq_exit+0x61/0xd0
  [<ffffffff81018d25>] do_IRQ+0x65/0x110
  [<ffffffff81672189>] common_interrupt+0x89/0x89
  <EOI>
  [<ffffffff814ffe11>] ? cpuidle_enter_state+0x151/0x200
  [<ffffffff814ffee2>] cpuidle_enter+0x12/0x20
  [<ffffffff8109a6ae>] call_cpuidle+0x1e/0x40
  [<ffffffff8109a8f6>] cpu_startup_entry+0x146/0x220
  [<ffffffff810336f8>] start_secondary+0x148/0x170

Signed-off-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Fixes: d94a461 ("ath9k: use ieee80211_tx_status_noskb where possible")
Acked-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
djdeath pushed a commit to djdeath/linux that referenced this issue Apr 26, 2017
[ Upstream commit 45caeaa ]

As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.

We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:

 rib#8 [] page_fault at ffffffff8163e648
    [exception RIP: __tcp_ack_snd_check+74]
.
.
 rib#9 [] tcp_rcv_established at ffffffff81580b64
rib#10 [] tcp_v4_do_rcv at ffffffff8158b54a
rib#11 [] tcp_v4_rcv at ffffffff8158cd02
rib#12 [] ip_local_deliver_finish at ffffffff815668f4
rib#13 [] ip_local_deliver at ffffffff81566bd9
rib#14 [] ip_rcv_finish at ffffffff8156656d
rib#15 [] ip_rcv at ffffffff81566f06
rib#16 [] __netif_receive_skb_core at ffffffff8152b3a2
rib#17 [] __netif_receive_skb at ffffffff8152b608
rib#18 [] netif_receive_skb at ffffffff8152b690
rib#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
rib#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
rib#21 [] net_rx_action at ffffffff8152bac2
rib#22 [] __do_softirq at ffffffff81084b4f
rib#23 [] call_softirq at ffffffff8164845c
rib#24 [] do_softirq at ffffffff81016fc5
rib#25 [] irq_exit at ffffffff81084ee5
torvalds#26 [] do_IRQ at ffffffff81648ff8

Of course it may happen with other NIC drivers as well.

It's found the freed dst_entry here:

 224 static bool tcp_in_quickack_mode(struct sock *sk)↩
 225 {↩
 226 ▹       const struct inet_connection_sock *icsk = inet_csk(sk);↩
 227 ▹       const struct dst_entry *dst = __sk_dst_get(sk);↩
 228 ↩
 229 ▹       return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
 230 ▹       ▹       (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
 231 }↩

But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.

All the vmcores showed 2 significant clues:

- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.

- All vmcores showed a postitive LockDroppedIcmps value, e.g:

LockDroppedIcmps                  267

A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:

do_redirect()->__sk_dst_check()-> dst_release().

Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.

To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.

The dccp/IPv6 code is very similar in this respect, so fixing it there too.

As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().

Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
djdeath pushed a commit to djdeath/linux that referenced this issue May 8, 2017
mipsxx_pmu_handle_shared_irq() calls irq_work_run() while holding the
pmuint_rwlock for read.  irq_work_run() can, via perf_pending_event(),
call try_to_wake_up() which can try to take rq->lock.

However, perf can also call perf_pmu_enable() (and thus take the
pmuint_rwlock for write) while holding the rq->lock, from
finish_task_switch() via perf_event_context_sched_in().

This leads to an ABBA deadlock:

 PID: 3855   TASK: 8f7ce288  CPU: 2   COMMAND: "process"
  #0 [89c39ac8] __delay at 803b5be4
  rib#1 [89c39ac8] do_raw_spin_lock at 8008fdcc
  rib#2 [89c39af8] try_to_wake_up at 8006e47c
  rib#3 [89c39b38] pollwake at 8018eab0
  rib#4 [89c39b68] __wake_up_common at 800879f4
  rib#5 [89c39b98] __wake_up at 800880e4
  rib#6 [89c39bc8] perf_event_wakeup at 8012109c
  rib#7 [89c39be8] perf_pending_event at 80121184
  rib#8 [89c39c08] irq_work_run_list at 801151f0
  rib#9 [89c39c38] irq_work_run at 80115274
 rib#10 [89c39c50] mipsxx_pmu_handle_shared_irq at 8002cc7c

 PID: 1481   TASK: 8eaac6a8  CPU: 3   COMMAND: "process"
  #0 [8de7f900] do_raw_write_lock at 800900e0
  rib#1 [8de7f918] perf_event_context_sched_in at 80122310
  rib#2 [8de7f938] __perf_event_task_sched_in at 80122608
  rib#3 [8de7f958] finish_task_switch at 8006b8a4
  rib#4 [8de7f998] __schedule at 805e4dc4
  rib#5 [8de7f9f8] schedule at 805e5558
  rib#6 [8de7fa10] schedule_hrtimeout_range_clock at 805e9984
  rib#7 [8de7fa70] poll_schedule_timeout at 8018e8f8
  rib#8 [8de7fa88] do_select at 8018f338
  rib#9 [8de7fd88] core_sys_select at 8018f5cc
 rib#10 [8de7fee0] sys_select at 8018f854
 rib#11 [8de7ff28] syscall_common at 80028fc8

The lock seems to be there to protect the hardware counters so there is
no need to hold it across irq_work_run().

Signed-off-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
djdeath pushed a commit to djdeath/linux that referenced this issue May 24, 2017
On powerpc we can build the kernel with two different ABIs for mcount(), which
is used by ftrace. Kernels built with one ABI do not know how to load modules
built with the other ABI. The new style ABI is called "mprofile-kernel", for
want of a better name.

Currently if we build a module using the old style ABI, and the kernel with
mprofile-kernel, when we load the module we'll oops something like:

  # insmod autofs4-no-mprofile-kernel.ko
  ftrace-powerpc: Unexpected instruction f8810028 around bl _mcount
  ------------[ cut here ]------------
  WARNING: CPU: 6 PID: 3759 at ../kernel/trace/ftrace.c:2024 ftrace_bug+0x2b8/0x3c0
  CPU: 6 PID: 3759 Comm: insmod Not tainted 4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 rib#11
  ...
  NIP [c0000000001eaa48] ftrace_bug+0x2b8/0x3c0
  LR [c0000000001eaff8] ftrace_process_locs+0x4a8/0x590
  Call Trace:
    alloc_pages_current+0xc4/0x1d0 (unreliable)
    ftrace_process_locs+0x4a8/0x590
    load_module+0x1c8c/0x28f0
    SyS_finit_module+0x110/0x140
    system_call+0x38/0xfc
  ...
  ftrace failed to modify
  [<d000000002a31024>] 0xd000000002a31024
   actual:   35:65:00:48

We can avoid this by including in the vermagic whether the kernel/module was
built with mprofile-kernel. Which results in:

  # insmod autofs4-pg.ko
  autofs4: version magic
  '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 SMP mod_unload modversions '
  should be
  '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269-dirty SMP mod_unload modversions mprofile-kernel'
  insmod: ERROR: could not insert module autofs4-pg.ko: Invalid module format

Fixes: 8c50b72 ("powerpc/ftrace: Add Kconfig & Make glue for mprofile-kernel")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Jessica Yu <jeyu@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
djdeath pushed a commit to djdeath/linux that referenced this issue May 25, 2017
[ Upstream commit 45caeaa ]

As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.

We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:

 rib#8 [] page_fault at ffffffff8163e648
    [exception RIP: __tcp_ack_snd_check+74]
.
.
 rib#9 [] tcp_rcv_established at ffffffff81580b64
rib#10 [] tcp_v4_do_rcv at ffffffff8158b54a
rib#11 [] tcp_v4_rcv at ffffffff8158cd02
rib#12 [] ip_local_deliver_finish at ffffffff815668f4
rib#13 [] ip_local_deliver at ffffffff81566bd9
rib#14 [] ip_rcv_finish at ffffffff8156656d
rib#15 [] ip_rcv at ffffffff81566f06
rib#16 [] __netif_receive_skb_core at ffffffff8152b3a2
rib#17 [] __netif_receive_skb at ffffffff8152b608
rib#18 [] netif_receive_skb at ffffffff8152b690
rib#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
rib#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
rib#21 [] net_rx_action at ffffffff8152bac2
rib#22 [] __do_softirq at ffffffff81084b4f
rib#23 [] call_softirq at ffffffff8164845c
rib#24 [] do_softirq at ffffffff81016fc5
rib#25 [] irq_exit at ffffffff81084ee5
torvalds#26 [] do_IRQ at ffffffff81648ff8

Of course it may happen with other NIC drivers as well.

It's found the freed dst_entry here:

 224 static bool tcp_in_quickack_mode(struct sock *sk)↩
 225 {↩
 226 ▹       const struct inet_connection_sock *icsk = inet_csk(sk);↩
 227 ▹       const struct dst_entry *dst = __sk_dst_get(sk);↩
 228 ↩
 229 ▹       return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
 230 ▹       ▹       (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
 231 }↩

But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.

All the vmcores showed 2 significant clues:

- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.

- All vmcores showed a postitive LockDroppedIcmps value, e.g:

LockDroppedIcmps                  267

A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:

do_redirect()->__sk_dst_check()-> dst_release().

Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.

To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.

The dccp/IPv6 code is very similar in this respect, so fixing it there too.

As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().

Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
djdeath pushed a commit to djdeath/linux that referenced this issue Oct 26, 2017
Thomas reported that 'perf buildid-list' gets a SEGFAULT due to NULL
pointer deref when he ran it on a data with namespace events.  It was
because the buildid_id__mark_dso_hit_ops lacks the namespace event
handler and perf_too__fill_default() didn't set it.

  Program received signal SIGSEGV, Segmentation fault.
  0x0000000000000000 in ?? ()
  Missing separate debuginfos, use: dnf debuginfo-install audit-libs-2.7.7-1.fc25.s390x bzip2-libs-1.0.6-21.fc25.s390x elfutils-libelf-0.169-1.fc25.s390x
  +elfutils-libs-0.169-1.fc25.s390x libcap-ng-0.7.8-1.fc25.s390x numactl-libs-2.0.11-2.ibm.fc25.s390x openssl-libs-1.1.0e-1.1.ibm.fc25.s390x perl-libs-5.24.1-386.fc25.s390x
  +python-libs-2.7.13-2.fc25.s390x slang-2.3.0-7.fc25.s390x xz-libs-5.2.3-2.fc25.s390x zlib-1.2.8-10.fc25.s390x
  (gdb) where
  #0  0x0000000000000000 in ?? ()
  rib#1  0x00000000010fad6a in machines__deliver_event (machines=<optimized out>, machines@entry=0x2c6fd18,
      evlist=<optimized out>, event=event@entry=0x3fffdf00470, sample=0x3ffffffe880, sample@entry=0x3ffffffe888,
      tool=tool@entry=0x1312968 <build_id.mark_dso_hit_ops>, file_offset=1136) at util/session.c:1287
  rib#2  0x00000000010fbf4e in perf_session__deliver_event (file_offset=1136, tool=0x1312968 <build_id.mark_dso_hit_ops>,
      sample=0x3ffffffe888, event=0x3fffdf00470, session=0x2c6fc30) at util/session.c:1340
  rib#3  perf_session__process_event (session=0x2c6fc30, session@entry=0x0, event=event@entry=0x3fffdf00470,
      file_offset=file_offset@entry=1136) at util/session.c:1522
  rib#4  0x00000000010fddde in __perf_session__process_events (file_size=11880, data_size=<optimized out>,
      data_offset=<optimized out>, session=0x0) at util/session.c:1899
  rib#5  perf_session__process_events (session=0x0, session@entry=0x2c6fc30) at util/session.c:1953
  rib#6  0x000000000103b2ac in perf_session__list_build_ids (with_hits=<optimized out>, force=<optimized out>)
      at builtin-buildid-list.c:83
  rib#7  cmd_buildid_list (argc=<optimized out>, argv=<optimized out>) at builtin-buildid-list.c:115
  rib#8  0x00000000010a026c in run_builtin (p=0x1311f78 <commands+24>, argc=argc@entry=2, argv=argv@entry=0x3fffffff3c0)
      at perf.c:296
  rib#9  0x000000000102bc00 in handle_internal_command (argv=<optimized out>, argc=2) at perf.c:348
  rib#10 run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:392
  rib#11 main (argc=<optimized out>, argv=0x3fffffff3c0) at perf.c:536
  (gdb)

Fix it by adding a stub event handler for namespace event.

Committer testing:

Further clarifying, plain using 'perf buildid-list' will not end up in a
SEGFAULT when processing a perf.data file with namespace info:

  # perf record -a --namespaces sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 2.024 MB perf.data (1058 samples) ]
  # perf buildid-list | wc -l
  38
  # perf buildid-list | head -5
  e2a171c7b905826fc8494f0711ba76ab6abbd604 /lib/modules/4.14.0-rc3+/build/vmlinux
  874840a02d8f8a31cedd605d0b8653145472ced3 /lib/modules/4.14.0-rc3+/kernel/arch/x86/kvm/kvm-intel.ko
  ea7223776730cd8a22f320040aae4d54312984bc /lib/modules/4.14.0-rc3+/kernel/drivers/gpu/drm/i915/i915.ko
  5961535e6732a8edb7f22b3f148bb2fa2e0be4b9 /lib/modules/4.14.0-rc3+/kernel/drivers/gpu/drm/drm.ko
  f045f54aa78cf1931cc893f78b6cbc52c72a8cb1 /usr/lib64/libc-2.25.so
  #

It is only when one asks for checking what of those entries actually had
samples, i.e. when we use either -H or --with-hits, that we will process
all the PERF_RECORD_ events, and since tools/perf/builtin-buildid-list.c
neither explicitely set a perf_tool.namespaces() callback nor the
default stub was set that we end up, when processing a
PERF_RECORD_NAMESPACE record, causing a SEGFAULT:

  # perf buildid-list -H
  Segmentation fault (core dumped)
  ^C
  #

Reported-and-Tested-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Fixes: f3b3614 ("perf tools: Add PERF_RECORD_NAMESPACES to include namespaces related info")
Link: http://lkml.kernel.org/r/20171017132900.11043-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
djdeath pushed a commit to djdeath/linux that referenced this issue Mar 1, 2018
It was reported by Sergey Senozhatsky that if THP (Transparent Huge
Page) and frontswap (via zswap) are both enabled, when memory goes low
so that swap is triggered, segfault and memory corruption will occur in
random user space applications as follow,

kernel: urxvt[338]: segfault at 20 ip 00007fc08889ae0d sp 00007ffc73a7fc40 error 6 in libc-2.26.so[7fc08881a000+1ae000]
 #0  0x00007fc08889ae0d _int_malloc (libc.so.6)
 rib#1  0x00007fc08889c2f3 malloc (libc.so.6)
 rib#2  0x0000560e6004bff7 _Z14rxvt_wcstoutf8PKwi (urxvt)
 rib#3  0x0000560e6005e75c n/a (urxvt)
 rib#4  0x0000560e6007d9f1 _ZN16rxvt_perl_interp6invokeEP9rxvt_term9hook_typez (urxvt)
 rib#5  0x0000560e6003d988 _ZN9rxvt_term9cmd_parseEv (urxvt)
 rib#6  0x0000560e60042804 _ZN9rxvt_term6pty_cbERN2ev2ioEi (urxvt)
 rib#7  0x0000560e6005c10f _Z17ev_invoke_pendingv (urxvt)
 rib#8  0x0000560e6005cb55 ev_run (urxvt)
 rib#9  0x0000560e6003b9b9 main (urxvt)
 rib#10 0x00007fc08883af4a __libc_start_main (libc.so.6)
 rib#11 0x0000560e6003f9da _start (urxvt)

After bisection, it was found the first bad commit is bd4c82c ("mm,
THP, swap: delay splitting THP after swapped out").

The root cause is as follows:

When the pages are written to swap device during swapping out in
swap_writepage(), zswap (fontswap) is tried to compress the pages to
improve performance.  But zswap (frontswap) will treat THP as a normal
page, so only the head page is saved.  After swapping in, tail pages
will not be restored to their original contents, causing memory
corruption in the applications.

This is fixed by refusing to save page in the frontswap store functions
if the page is a THP.  So that the THP will be swapped out to swap
device.

Another choice is to split THP if frontswap is enabled.  But it is found
that the frontswap enabling isn't flexible.  For example, if
CONFIG_ZSWAP=y (cannot be module), frontswap will be enabled even if
zswap itself isn't enabled.

Frontswap has multiple backends, to make it easy for one backend to
enable THP support, the THP checking is put in backend frontswap store
functions instead of the general interfaces.

Link: http://lkml.kernel.org/r/20180209084947.22749-1-ying.huang@intel.com
Fixes: bd4c82c ("mm, THP, swap: delay splitting THP after swapped out")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Suggested-by: Minchan Kim <minchan@kernel.org>	[put THP checking in backend]
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Shaohua Li <shli@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org>	[4.14]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
djdeath pushed a commit to djdeath/linux that referenced this issue Dec 6, 2018
It was observed that a process blocked indefintely in
__fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP
to be cleared via fscache_wait_for_deferred_lookup().

At this time, ->backing_objects was empty, which would normaly prevent
__fscache_read_or_alloc_page() from getting to the point of waiting.
This implies that ->backing_objects was cleared *after*
__fscache_read_or_alloc_page was was entered.

When an object is "killed" and then "dropped",
FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then
KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is
->backing_objects cleared.  This leaves a window where
something else can set FSCACHE_COOKIE_LOOKING_UP and
__fscache_read_or_alloc_page() can start waiting, before
->backing_objects is cleared

There is some uncertainty in this analysis, but it seems to be fit the
observations.  Adding the wake in this patch will be handled correctly
by __fscache_read_or_alloc_page(), as it checks if ->backing_objects
is empty again, after waiting.

Customer which reported the hang, also report that the hang cannot be
reproduced with this fix.

The backtrace for the blocked process looked like:

PID: 29360  TASK: ffff881ff2ac0f80  CPU: 3   COMMAND: "zsh"
 #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1
 rib#1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed
 rib#2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8
 rib#3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e
 rib#4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache]
 rib#5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache]
 rib#6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs]
 rib#7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs]
 rib#8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73
 rib#9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs]
rib#10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756
rib#11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa
rib#12 [ffff881ff43eff18] sys_read at ffffffff811fda62
rib#13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David Howells <dhowells@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
…_map

Detected via gcc's ASan:

  Direct leak of 2048 byte(s) in 64 object(s) allocated from:
    6     #0 0x7f606512e370 in __interceptor_realloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee370)
    7     rib#1 0x556b0f1d7ddd in thread_map__realloc util/thread_map.c:43
    8     rib#2 0x556b0f1d84c7 in thread_map__new_by_tid util/thread_map.c:85
    9     rib#3 0x556b0f0e045e in is_event_supported util/parse-events.c:2250
   10     rib#4 0x556b0f0e1aa1 in print_hwcache_events util/parse-events.c:2382
   11     rib#5 0x556b0f0e3231 in print_events util/parse-events.c:2514
   12     rib#6 0x556b0ee0a66e in cmd_list /home/changbin/work/linux/tools/perf/builtin-list.c:58
   13     rib#7 0x556b0f01e0ae in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
   14     rib#8 0x556b0f01e859 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
   15     rib#9 0x556b0f01edc8 in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
   16     rib#10 0x556b0f01f71f in main /home/changbin/work/linux/tools/perf/perf.c:520
   17     rib#11 0x7f6062ccf09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 8989605 ("perf tools: Do not put a variable sized type not at the end of a struct")
Link: http://lkml.kernel.org/r/20190316080556.3075-3-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
…r-free issue

The evlist should be destroyed before the perf session.

Detected with gcc's ASan:

  =================================================================
  ==27350==ERROR: AddressSanitizer: heap-use-after-free on address 0x62b000002e38 at pc 0x5611da276999 bp 0x7ffce8f1d1a0 sp 0x7ffce8f1d190
  WRITE of size 8 at 0x62b000002e38 thread T0
      #0 0x5611da276998 in __list_del /home/work/linux/tools/include/linux/list.h:89
      rib#1 0x5611da276d4a in __list_del_entry /home/work/linux/tools/include/linux/list.h:102
      rib#2 0x5611da276e77 in list_del_init /home/work/linux/tools/include/linux/list.h:145
      rib#3 0x5611da2781cd in thread__put util/thread.c:130
      rib#4 0x5611da2cc0a8 in __thread__zput util/thread.h:68
      rib#5 0x5611da2d2dcb in hist_entry__delete util/hist.c:1148
      rib#6 0x5611da2cdf91 in hists__delete_entry util/hist.c:337
      rib#7 0x5611da2ce19e in hists__delete_entries util/hist.c:365
      rib#8 0x5611da2db2ab in hists__delete_all_entries util/hist.c:2639
      rib#9 0x5611da2db325 in hists_evsel__exit util/hist.c:2651
      rib#10 0x5611da1c5352 in perf_evsel__exit util/evsel.c:1304
      rib#11 0x5611da1c5390 in perf_evsel__delete util/evsel.c:1309
      rib#12 0x5611da1b35f0 in perf_evlist__purge util/evlist.c:124
      rib#13 0x5611da1b38e2 in perf_evlist__delete util/evlist.c:148
      rib#14 0x5611da069781 in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1645
      rib#15 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#16 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#17 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#18 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#19 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
      rib#20 0x5611d9ff35c9 in _start (/home/work/linux/tools/perf/perf+0x3e95c9)

  0x62b000002e38 is located 11320 bytes inside of 27448-byte region [0x62b000000200,0x62b000006d38)
  freed by thread T0 here:
      #0 0x7fdccb04ab70 in free (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedb70)
      rib#1 0x5611da260df4 in perf_session__delete util/session.c:201
      rib#2 0x5611da063de5 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1300
      rib#3 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642
      rib#4 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#5 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#6 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#7 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#8 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  previously allocated by thread T0 here:
      #0 0x7fdccb04b138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      rib#1 0x5611da26010c in zalloc util/util.h:23
      rib#2 0x5611da260824 in perf_session__new util/session.c:118
      rib#3 0x5611da0633a6 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1192
      rib#4 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642
      rib#5 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#6 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#7 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#8 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#9 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  SUMMARY: AddressSanitizer: heap-use-after-free /home/work/linux/tools/include/linux/list.h:89 in __list_del
  Shadow bytes around the buggy address:
    0x0c567fff8570: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff8580: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff8590: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff85a0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff85b0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  =>0x0c567fff85c0: fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd fd fd
    0x0c567fff85d0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff85e0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff85f0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff8600: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
    0x0c567fff8610: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  Shadow byte legend (one shadow byte represents 8 application bytes):
    Addressable:           00
    Partially addressable: 01 02 03 04 05 06 07
    Heap left redzone:       fa
    Freed heap region:       fd
    Stack left redzone:      f1
    Stack mid redzone:       f2
    Stack right redzone:     f3
    Stack after return:      f5
    Stack use after scope:   f8
    Global redzone:          f9
    Global init order:       f6
    Poisoned by user:        f7
    Container overflow:      fc
    Array cookie:            ac
    Intra object redzone:    bb
    ASan internal:           fe
    Left alloca redzone:     ca
    Right alloca redzone:    cb
  ==27350==ABORTING

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190316080556.3075-8-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
Using gcc's ASan, Changbin reports:

  =================================================================
  ==7494==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 48 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      rib#1 0x5625e5330a5e in zalloc util/util.h:23
      rib#2 0x5625e5330a9b in perf_counts__new util/counts.c:10
      rib#3 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47
      rib#4 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505
      rib#5 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347
      rib#6 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47
      rib#7 0x5625e51528e6 in run_test tests/builtin-test.c:358
      rib#8 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      rib#9 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      rib#10 0x5625e515572f in cmd_test tests/builtin-test.c:722
      rib#11 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#12 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#13 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#14 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#15 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  Indirect leak of 72 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      rib#1 0x5625e532560d in zalloc util/util.h:23
      rib#2 0x5625e532566b in xyarray__new util/xyarray.c:10
      rib#3 0x5625e5330aba in perf_counts__new util/counts.c:15
      rib#4 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47
      rib#5 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505
      rib#6 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347
      rib#7 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47
      rib#8 0x5625e51528e6 in run_test tests/builtin-test.c:358
      rib#9 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      rib#10 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      rib#11 0x5625e515572f in cmd_test tests/builtin-test.c:722
      rib#12 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#13 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#14 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#15 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#16 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

His patch took care of evsel->prev_raw_counts, but the above backtraces
are about evsel->counts, so fix that instead.

Reported-by: Changbin Du <changbin.du@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/n/tip-hd1x13g59f0nuhe4anxhsmfp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
…_event_on_all_cpus test

  =================================================================
  ==7497==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a88f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
      rib#1 0x5625e5326213 in cpu_map__trim_new util/cpumap.c:45
      rib#2 0x5625e5326703 in cpu_map__read util/cpumap.c:103
      rib#3 0x5625e53267ef in cpu_map__read_all_cpu_map util/cpumap.c:120
      rib#4 0x5625e5326915 in cpu_map__new util/cpumap.c:135
      rib#5 0x5625e517b355 in test__openat_syscall_event_on_all_cpus tests/openat-syscall-all-cpus.c:36
      rib#6 0x5625e51528e6 in run_test tests/builtin-test.c:358
      rib#7 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      rib#8 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      rib#9 0x5625e515572f in cmd_test tests/builtin-test.c:722
      rib#10 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#11 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#12 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#13 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#14 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: f30a79b ("perf tools: Add reference counting for cpu_map object")
Link: http://lkml.kernel.org/r/20190316080556.3075-15-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
  =================================================================
  ==7506==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 13 byte(s) in 3 object(s) allocated from:
      #0 0x7f03339d6070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
      rib#1 0x5625e53aaef0 in expr__find_other util/expr.y:221
      rib#2 0x5625e51bcd3f in test__expr tests/expr.c:52
      rib#3 0x5625e51528e6 in run_test tests/builtin-test.c:358
      rib#4 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      rib#5 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      rib#6 0x5625e515572f in cmd_test tests/builtin-test.c:722
      rib#7 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#8 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#9 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#10 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#11 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 0751673 ("perf tools: Add a simple expression parser for JSON")
Link: http://lkml.kernel.org/r/20190316080556.3075-16-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
  =================================================================
  ==20875==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 1160 byte(s) in 1 object(s) allocated from:
      #0 0x7f1b6fc84138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      rib#1 0x55bd50005599 in zalloc util/util.h:23
      rib#2 0x55bd500068f5 in perf_evsel__newtp_idx util/evsel.c:327
      rib#3 0x55bd4ff810fc in perf_evsel__newtp /home/work/linux/tools/perf/util/evsel.h:216
      rib#4 0x55bd4ff81608 in test__perf_evsel__tp_sched_test tests/evsel-tp-sched.c:69
      rib#5 0x55bd4ff528e6 in run_test tests/builtin-test.c:358
      rib#6 0x55bd4ff52baf in test_and_print tests/builtin-test.c:388
      rib#7 0x55bd4ff543fe in __cmd_test tests/builtin-test.c:583
      rib#8 0x55bd4ff5572f in cmd_test tests/builtin-test.c:722
      rib#9 0x55bd4ffc4087 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#10 0x55bd4ffc45c6 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#11 0x55bd4ffc49ca in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#12 0x55bd4ffc5138 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#13 0x7f1b6e34809a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  Indirect leak of 19 byte(s) in 1 object(s) allocated from:
      #0 0x7f1b6fc83f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
      rib#1 0x7f1b6e3ac30f in vasprintf (/lib/x86_64-linux-gnu/libc.so.6+0x8830f)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 6a6cd11 ("perf test: Add test for the sched tracepoint format fields")
Link: http://lkml.kernel.org/r/20190316080556.3075-17-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
djdeath pushed a commit to djdeath/linux that referenced this issue Apr 8, 2019
…ll_sock().

When it is to cleanup net namespace, rds_tcp_exit_net() will call
rds_tcp_kill_sock(), if t_sock is NULL, it will not call
rds_conn_destroy(), rds_conn_path_destroy() and rds_tcp_conn_free() to free
connection, and the worker cp_conn_w is not stopped, afterwards the net is freed in
net_drop_ns(); While cp_conn_w rds_connect_worker() will call rds_tcp_conn_path_connect()
and reference 'net' which has already been freed.

In rds_tcp_conn_path_connect(), rds_tcp_set_callbacks() will set t_sock = sock before
sock->ops->connect, but if connect() is failed, it will call
rds_tcp_restore_callbacks() and set t_sock = NULL, if connect is always
failed, rds_connect_worker() will try to reconnect all the time, so
rds_tcp_kill_sock() will never to cancel worker cp_conn_w and free the
connections.

Therefore, the condition !tc->t_sock is not needed if it is going to do
cleanup_net->rds_tcp_exit_net->rds_tcp_kill_sock, because tc->t_sock is always
NULL, and there is on other path to cancel cp_conn_w and free
connection. So this patch is to fix this.

rds_tcp_kill_sock():
...
if (net != c_net || !tc->t_sock)
...
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>

==================================================================
BUG: KASAN: use-after-free in inet_create+0xbcc/0xd28
net/ipv4/af_inet.c:340
Read of size 4 at addr ffff8003496a4684 by task kworker/u8:4/3721

CPU: 3 PID: 3721 Comm: kworker/u8:4 Not tainted 5.1.0 rib#11
Hardware name: linux,dummy-virt (DT)
Workqueue: krdsd rds_connect_worker
Call trace:
 dump_backtrace+0x0/0x3c0 arch/arm64/kernel/time.c:53
 show_stack+0x28/0x38 arch/arm64/kernel/traps.c:152
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x120/0x188 lib/dump_stack.c:113
 print_address_description+0x68/0x278 mm/kasan/report.c:253
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x21c/0x348 mm/kasan/report.c:409
 __asan_report_load4_noabort+0x30/0x40 mm/kasan/report.c:429
 inet_create+0xbcc/0xd28 net/ipv4/af_inet.c:340
 __sock_create+0x4f8/0x770 net/socket.c:1276
 sock_create_kern+0x50/0x68 net/socket.c:1322
 rds_tcp_conn_path_connect+0x2b4/0x690 net/rds/tcp_connect.c:114
 rds_connect_worker+0x108/0x1d0 net/rds/threads.c:175
 process_one_work+0x6e8/0x1700 kernel/workqueue.c:2153
 worker_thread+0x3b0/0xdd0 kernel/workqueue.c:2296
 kthread+0x2f0/0x378 kernel/kthread.c:255
 ret_from_fork+0x10/0x18 arch/arm64/kernel/entry.S:1117

Allocated by task 687:
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xd4/0x180 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x14/0x20 mm/kasan/kasan.c:490
 slab_post_alloc_hook mm/slab.h:444 [inline]
 slab_alloc_node mm/slub.c:2705 [inline]
 slab_alloc mm/slub.c:2713 [inline]
 kmem_cache_alloc+0x14c/0x388 mm/slub.c:2718
 kmem_cache_zalloc include/linux/slab.h:697 [inline]
 net_alloc net/core/net_namespace.c:384 [inline]
 copy_net_ns+0xc4/0x2d0 net/core/net_namespace.c:424
 create_new_namespaces+0x300/0x658 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xa0/0x198 kernel/nsproxy.c:206
 ksys_unshare+0x340/0x628 kernel/fork.c:2577
 __do_sys_unshare kernel/fork.c:2645 [inline]
 __se_sys_unshare kernel/fork.c:2643 [inline]
 __arm64_sys_unshare+0x38/0x58 kernel/fork.c:2643
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:47 [inline]
 el0_svc_common+0x168/0x390 arch/arm64/kernel/syscall.c:83
 el0_svc_handler+0x60/0xd0 arch/arm64/kernel/syscall.c:129
 el0_svc+0x8/0xc arch/arm64/kernel/entry.S:960

Freed by task 264:
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x114/0x220 mm/kasan/kasan.c:521
 kasan_slab_free+0x10/0x18 mm/kasan/kasan.c:528
 slab_free_hook mm/slub.c:1370 [inline]
 slab_free_freelist_hook mm/slub.c:1397 [inline]
 slab_free mm/slub.c:2952 [inline]
 kmem_cache_free+0xb8/0x3a8 mm/slub.c:2968
 net_free net/core/net_namespace.c:400 [inline]
 net_drop_ns.part.6+0x78/0x90 net/core/net_namespace.c:407
 net_drop_ns net/core/net_namespace.c:406 [inline]
 cleanup_net+0x53c/0x6d8 net/core/net_namespace.c:569
 process_one_work+0x6e8/0x1700 kernel/workqueue.c:2153
 worker_thread+0x3b0/0xdd0 kernel/workqueue.c:2296
 kthread+0x2f0/0x378 kernel/kthread.c:255
 ret_from_fork+0x10/0x18 arch/arm64/kernel/entry.S:1117

The buggy address belongs to the object at ffff8003496a3f80
 which belongs to the cache net_namespace of size 7872
The buggy address is located 1796 bytes inside of
 7872-byte region [ffff8003496a3f80, ffff8003496a5e40)
The buggy address belongs to the page:
page:ffff7e000d25a800 count:1 mapcount:0 mapping:ffff80036ce4b000
index:0x0 compound_mapcount: 0
flags: 0xffffe0000008100(slab|head)
raw: 0ffffe0000008100 dead000000000100 dead000000000200 ffff80036ce4b000
raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8003496a4580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8003496a4600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8003496a4680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8003496a4700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8003496a4780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Fixes: 467fa15("RDS-TCP: Support multiple RDS-TCP listen endpoints, one per netns.")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Mao Wenan <maowenan@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
By calling maps__insert() we assume to get 2 references on the map,
which we relese within maps__remove call.

However if there's already same map name, we currently don't bump the
reference and can crash, like:

  Program received signal SIGABRT, Aborted.
  0x00007ffff75e60f5 in raise () from /lib64/libc.so.6

  (gdb) bt
  #0  0x00007ffff75e60f5 in raise () from /lib64/libc.so.6
  rib#1  0x00007ffff75d0895 in abort () from /lib64/libc.so.6
  rib#2  0x00007ffff75d0769 in __assert_fail_base.cold () from /lib64/libc.so.6
  rib#3  0x00007ffff75de596 in __assert_fail () from /lib64/libc.so.6
  rib#4  0x00000000004fc006 in refcount_sub_and_test (i=1, r=0x1224e88) at tools/include/linux/refcount.h:131
  rib#5  refcount_dec_and_test (r=0x1224e88) at tools/include/linux/refcount.h:148
  rib#6  map__put (map=0x1224df0) at util/map.c:299
  rib#7  0x00000000004fdb95 in __maps__remove (map=0x1224df0, maps=0xb17d80) at util/map.c:953
  rib#8  maps__remove (maps=0xb17d80, map=0x1224df0) at util/map.c:959
  rib#9  0x00000000004f7d8a in map_groups__remove (map=<optimized out>, mg=<optimized out>) at util/map_groups.h:65
  rib#10 machine__process_ksymbol_unregister (sample=<optimized out>, event=0x7ffff7279670, machine=<optimized out>) at util/machine.c:728
  rib#11 machine__process_ksymbol (machine=<optimized out>, event=0x7ffff7279670, sample=<optimized out>) at util/machine.c:741
  rib#12 0x00000000004fffbb in perf_session__deliver_event (session=0xb11390, event=0x7ffff7279670, tool=0x7fffffffc7b0, file_offset=13936) at util/session.c:1362
  rib#13 0x00000000005039bb in do_flush (show_progress=false, oe=0xb17e80) at util/ordered-events.c:243
  rib#14 __ordered_events__flush (oe=0xb17e80, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:322
  rib#15 0x00000000005005e4 in perf_session__process_user_event (session=session@entry=0xb11390, event=event@entry=0x7ffff72a4af8,
  ...

Add the map to the list and getting the reference event if we find the
map with same name.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Fixes: 1e62856 ("perf symbols: Fix slowness due to -ffunction-section")
Link: http://lkml.kernel.org/r/20190416160127.30203-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matt-auld pushed a commit to matt-auld/linux that referenced this issue May 24, 2022
Kernel panic when injecting memory_failure for the global huge_zero_page,
when CONFIG_DEBUG_VM is enabled, as follows.

  Injecting memory failure for pfn 0x109ff9 at process virtual address 0x20ff9000
  page:00000000fb053fc3 refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109e00
  head:00000000fb053fc3 order:9 compound_mapcount:0 compound_pincount:0
  flags: 0x17fffc000010001(locked|head|node=0|zone=2|lastcpupid=0x1ffff)
  raw: 017fffc000010001 0000000000000000 dead000000000122 0000000000000000
  raw: 0000000000000000 0000000000000000 00000002ffffffff 0000000000000000
  page dumped because: VM_BUG_ON_PAGE(is_huge_zero_page(head))
  ------------[ cut here ]------------
  kernel BUG at mm/huge_memory.c:2499!
  invalid opcode: 0000 [rib#1] PREEMPT SMP PTI
  CPU: 6 PID: 553 Comm: split_bug Not tainted 5.18.0-rc1+ rib#11
  Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 3288b3c 04/01/2014
  RIP: 0010:split_huge_page_to_list+0x66a/0x880
  Code: 84 9b fb ff ff 48 8b 7c 24 08 31 f6 e8 9f 5d 2a 00 b8 b8 02 00 00 e9 e8 fb ff ff 48 c7 c6 e8 47 3c 82 4c b
  RSP: 0018:ffffc90000dcbdf8 EFLAGS: 00010246
  RAX: 000000000000003c RBX: 0000000000000001 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: ffffffff823e4c4f RDI: 00000000ffffffff
  RBP: ffff88843fffdb40 R08: 0000000000000000 R09: 00000000fffeffff
  R10: ffffc90000dcbc48 R11: ffffffff82d68448 R12: ffffea0004278000
  R13: ffffffff823c6203 R14: 0000000000109ff9 R15: ffffea000427fe40
  FS:  00007fc375a26740(0000) GS:ffff88842fd80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fc3757c9290 CR3: 0000000102174006 CR4: 00000000003706e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
  try_to_split_thp_page+0x3a/0x130
  memory_failure+0x128/0x800
  madvise_inject_error.cold+0x8b/0xa1
  __x64_sys_madvise+0x54/0x60
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae
  RIP: 0033:0x7fc3754f8bf9
  Code: 01 00 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 8
  RSP: 002b:00007ffeda93a1d8 EFLAGS: 00000217 ORIG_RAX: 000000000000001c
  RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc3754f8bf9
  RDX: 0000000000000064 RSI: 0000000000003000 RDI: 0000000020ff9000
  RBP: 00007ffeda93a200 R08: 0000000000000000 R09: 0000000000000000
  R10: 00000000ffffffff R11: 0000000000000217 R12: 0000000000400490
  R13: 00007ffeda93a2e0 R14: 0000000000000000 R15: 0000000000000000

We think that raising BUG is overkilling for splitting huge_zero_page, the
huge_zero_page can't be met from normal paths other than memory failure,
but memory failure is a valid caller.  So we tend to replace the BUG to
WARN + returning -EBUSY, and thus the panic above won't happen again.

Link: https://lkml.kernel.org/r/f35f8b97377d5d3ede1bc5ac3114da888c57cbce.1651052574.git.xuyu@linux.alibaba.com
Fixes: d173d54 ("mm/memory-failure.c: skip huge_zero_page in memory_failure()")
Fixes: 6a46079 ("HWPOISON: The high level memory error handler in the VM v7")
Signed-off-by: Xu Yu <xuyu@linux.alibaba.com>
Suggested-by: Yang Shi <shy828301@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matt-auld pushed a commit to matt-auld/linux that referenced this issue May 24, 2022
Do not allow to write timestamps on RX rings if PF is being configured.
When PF is being configured RX rings can be freed or rebuilt. If at the
same time timestamps are updated, the kernel will crash by dereferencing
null RX ring pointer.

PID: 1449   TASK: ff187d28ed658040  CPU: 34  COMMAND: "ice-ptp-0000:51"
 #0 [ff1966a94a713bb0] machine_kexec at ffffffff9d05a0be
 rib#1 [ff1966a94a713c08] __crash_kexec at ffffffff9d192e9d
 rib#2 [ff1966a94a713cd0] crash_kexec at ffffffff9d1941bd
 rib#3 [ff1966a94a713ce8] oops_end at ffffffff9d01bd54
 rib#4 [ff1966a94a713d08] no_context at ffffffff9d06bda4
 rib#5 [ff1966a94a713d60] __bad_area_nosemaphore at ffffffff9d06c10c
 rib#6 [ff1966a94a713da8] do_page_fault at ffffffff9d06cae4
 rib#7 [ff1966a94a713de0] page_fault at ffffffff9da0107e
    [exception RIP: ice_ptp_update_cached_phctime+91]
    RIP: ffffffffc076db8b  RSP: ff1966a94a713e98  RFLAGS: 00010246
    RAX: 16e3db9c6b7ccae4  RBX: ff187d269dd3c180  RCX: ff187d269cd4d018
    RDX: 0000000000000000  RSI: 0000000000000000  RDI: 0000000000000000
    RBP: ff187d269cfcc644   R8: ff187d339b9641b0   R9: 0000000000000000
    R10: 0000000000000002  R11: 0000000000000000  R12: ff187d269cfcc648
    R13: ffffffff9f128784  R14: ffffffff9d101b70  R15: ff187d269cfcc640
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 rib#8 [ff1966a94a713ea0] ice_ptp_periodic_work at ffffffffc076dbef [ice]
 rib#9 [ff1966a94a713ee0] kthread_worker_fn at ffffffff9d101c1b
 rib#10 [ff1966a94a713f10] kthread at ffffffff9d101b4d
 rib#11 [ff1966a94a713f50] ret_from_fork at ffffffff9da0023f

Fixes: 77a7811 ("ice: enable receive hardware timestamping")
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Michal Schmidt <mschmidt@redhat.com>
Tested-by: Dave Cain <dcain@redhat.com>
Tested-by: Gurucharan <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
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