kfree() is incorrectly used to release the pages allocated by
__get_free_page() and __get_free_pages(). Use the matching deallocators
i.e., free_page() and free_pages(), respectively.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
This reverts commit b3cf8528bb.
That commit unintentionally broke Xen balloon memory hotplug with
"hotplug_unpopulated" set to 1. As long as "System RAM" resource
got assigned under a new "Unusable memory" resource in IO/Mem tree
any attempt to online this memory would fail due to general kernel
restrictions on having "System RAM" resources as 1st level only.
The original issue that commit has tried to workaround fa564ad963
("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f,
60-7f)") also got amended by the following 03a551734 ("x86/PCI: Move
and shrink AMD 64-bit window to avoid conflict") which made the
original fix to Xen ballooning unnecessary.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Failure of an element of a Xen multicall is signalled via a WARN()
only if the kernel is compiled with MC_DEBUG. It is impossible to
know which element failed and why it did so.
Change that by printing the related information even without MC_DEBUG,
even if maybe in some limited form (e.g. without information which
caller produced the failing element).
Move the printing out of the switch statement in order to have the
same information for a single call.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Since commit 4378a7d4be ("arm64: implement syscall wrappers")
introduced "__arm64_" prefix to all syscall wrapper symbols in
sys_call_table, syscall tracer can not find corresponding
metadata from syscall name. In the result, we have no syscall
ftrace events on arm64 kernel, and some bpf testcases are failed
on arm64.
To fix this issue, this introduces custom
arch_syscall_match_sym_name() which skips first 8 bytes when
comparing the syscall and symbol names.
Fixes: 4378a7d4be ("arm64: implement syscall wrappers")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual address
for a cacheable mapping of a location is being accessed by a core while
another core is remapping the virtual address to a new physical page
using the recommended break-before-make sequence, then under very rare
circumstances TLBI+DSB completes before a read using the translation
being invalidated has been observed by other observers. The workaround
repeats the TLBI+DSB operation and is shared with the Qualcomm Falkor
erratum 1009
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Commit 32a4f5ecd7 ("net: sched: introduce chain object to uapi")
added new RTM_* definitions without properly updating SELinux, this
patch adds the necessary SELinux support.
While there was a BUILD_BUG_ON() in the SELinux code to protect from
exactly this case, it was bypassed in the broken commit. In order to
hopefully prevent this from happening in the future, add additional
comments which provide some instructions on how to resolve the
BUILD_BUG_ON() failures.
Fixes: 32a4f5ecd7 ("net: sched: introduce chain object to uapi")
Cc: <stable@vger.kernel.org> # 4.19
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>
of_dma_controller_free() was not called on module onloading.
This lead to a soft lockup:
watchdog: BUG: soft lockup - CPU#0 stuck for 23s!
Modules linked in: at_hdmac [last unloaded: at_hdmac]
when of_dma_request_slave_channel() tried to call ofdma->of_dma_xlate().
Cc: stable@vger.kernel.org
Fixes: bbe89c8e3d ("at_hdmac: move to generic DMA binding")
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The leak was found when opening/closing a serial port a great number of
time, increasing kmalloc-32 in slabinfo.
Each time the port was opened, dma_request_slave_channel() was called.
Then, in at_dma_xlate(), atslave was allocated with devm_kzalloc() and
never freed. (Well, it was free at module unload, but that's not what we
want).
So, here, kzalloc is more suited for the job since it has to be freed in
atc_free_chan_resources().
Cc: stable@vger.kernel.org
Fixes: bbe89c8e3d ("at_hdmac: move to generic DMA binding")
Reported-by: Mario Forner <m.forner@be4energy.com>
Suggested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In this second set of fixes for the current -rc cycle, we have some
regressions fixes for the old omap_udc driver done by Aaro Koskinen.
We're also reverting an old patch on dwc3 which is, now, known to
break USB certification in some cases.
We have a fix on u_ether for an unsafe list iteration.
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Merge tag 'fixes-for-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-linus
Felipe writes:
USB: fixes for v4.20-rc4
In this second set of fixes for the current -rc cycle, we have some
regressions fixes for the old omap_udc driver done by Aaro Koskinen.
We're also reverting an old patch on dwc3 which is, now, known to
break USB certification in some cases.
We have a fix on u_ether for an unsafe list iteration.
* tag 'fixes-for-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb:
usb: gadget: u_ether: fix unsafe list iteration
USB: omap_udc: fix rejection of out transfers when DMA is used
USB: omap_udc: fix USB gadget functionality on Palm Tungsten E
USB: omap_udc: fix omap_udc_start() on 15xx machines
USB: omap_udc: fix crashes on probe error and module removal
USB: omap_udc: use devm_request_irq()
Revert "usb: dwc3: gadget: skip Set/Clear Halt when invalid"
- Revert: Don't try to validate ports while destroying them (Lyude)
- core: Don't set device to master unless set_master succeeds (Sergio)
- meson: Do vblank_on/off on enable/disable (Neil)
- meson: Use fast_io regmap option to avoid sleeping in irq ctx (Lyude)
- meson: Don't walk off the end of the OSD EOTF LUTs (Lyude)
Cc: Lyude Paul <lyude@redhat.com>
Cc: Sergio Correia <sergio@correia.cc>
Cc: Neil Armstrong <narmstrong@baylibre.com>
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Merge tag 'drm-misc-fixes-2018-11-28-1' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
- mst: Don't try to validate ports while destroying them (Lyude)
- Revert: Don't try to validate ports while destroying them (Lyude)
- core: Don't set device to master unless set_master succeeds (Sergio)
- meson: Do vblank_on/off on enable/disable (Neil)
- meson: Use fast_io regmap option to avoid sleeping in irq ctx (Lyude)
- meson: Don't walk off the end of the OSD EOTF LUTs (Lyude)
Cc: Lyude Paul <lyude@redhat.com>
Cc: Sergio Correia <sergio@correia.cc>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20181128212936.GA21379@art_vandelay
If the platform has no IO space, ioregs is placed next to the already
allocated regs. In this case, it should not be separately freed.
This prevents a kernel warning from __vunmap "Trying to vfree()
nonexistent vm area" when unloading the driver.
Fixes: 0dd68309b9 ("drm/ast: Try to use MMIO registers when PIO isn't supported")
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This reverts commit:
c54c7374ff ("drm/dp_mst: Skip validating ports during destruction, just ref")
ugh.
In drm_dp_destroy_connector_work(), we have a pretty good chance of
freeing the actual struct drm_dp_mst_port. However, after destroying
things we send a hotplug through (*mgr->cbs->hotplug)(mgr) which is
where the problems start.
For i915, this calls all the way down to the fbcon probing helpers,
which start trying to access the port in a modeset.
[ 45.062001] ==================================================================
[ 45.062112] BUG: KASAN: use-after-free in ex_handler_refcount+0x146/0x180
[ 45.062196] Write of size 4 at addr ffff8882b4b70968 by task kworker/3:1/53
[ 45.062325] CPU: 3 PID: 53 Comm: kworker/3:1 Kdump: loaded Tainted: G O 4.20.0-rc4Lyude-Test+ #3
[ 45.062442] Hardware name: LENOVO 20BWS1KY00/20BWS1KY00, BIOS JBET71WW (1.35 ) 09/14/2018
[ 45.062554] Workqueue: events drm_dp_destroy_connector_work [drm_kms_helper]
[ 45.062641] Call Trace:
[ 45.062685] dump_stack+0xbd/0x15a
[ 45.062735] ? dump_stack_print_info.cold.0+0x1b/0x1b
[ 45.062801] ? printk+0x9f/0xc5
[ 45.062847] ? kmsg_dump_rewind_nolock+0xe4/0xe4
[ 45.062909] ? ex_handler_refcount+0x146/0x180
[ 45.062970] print_address_description+0x71/0x239
[ 45.063036] ? ex_handler_refcount+0x146/0x180
[ 45.063095] kasan_report.cold.5+0x242/0x30b
[ 45.063155] __asan_report_store4_noabort+0x1c/0x20
[ 45.063313] ex_handler_refcount+0x146/0x180
[ 45.063371] ? ex_handler_clear_fs+0xb0/0xb0
[ 45.063428] fixup_exception+0x98/0xd7
[ 45.063484] ? raw_notifier_call_chain+0x20/0x20
[ 45.063548] do_trap+0x6d/0x210
[ 45.063605] ? _GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[ 45.063732] do_error_trap+0xc0/0x170
[ 45.063802] ? _GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[ 45.063929] do_invalid_op+0x3b/0x50
[ 45.063997] ? _GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[ 45.064103] invalid_op+0x14/0x20
[ 45.064162] RIP: 0010:_GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[ 45.064274] Code: 00 48 c7 c7 80 fe 53 a0 48 89 e5 e8 5b 6f 26 e1 5d c3 48 8d 0e 0f 0b 48 8d 0b 0f 0b 48 8d 0f 0f 0b 48 8d 0f 0f 0b 49 8d 4d 00 <0f> 0b 49 8d 0e 0f 0b 48 8d 08 0f 0b 49 8d 4d 00 0f 0b 48 8d 0b 0f
[ 45.064569] RSP: 0018:ffff8882b789ee10 EFLAGS: 00010282
[ 45.064637] RAX: ffff8882af47ae70 RBX: ffff8882af47aa60 RCX: ffff8882b4b70968
[ 45.064723] RDX: ffff8882af47ae70 RSI: 0000000000000008 RDI: ffff8882b788bdb8
[ 45.064808] RBP: ffff8882b789ee28 R08: ffffed1056f13db4 R09: ffffed1056f13db3
[ 45.064894] R10: ffffed1056f13db3 R11: ffff8882b789ed9f R12: ffff8882af47ad28
[ 45.064980] R13: ffff8882b4b70968 R14: ffff8882acd86728 R15: ffff8882b4b75dc8
[ 45.065084] drm_dp_mst_reset_vcpi_slots+0x12/0x80 [drm_kms_helper]
[ 45.065225] intel_mst_disable_dp+0xda/0x180 [i915]
[ 45.065361] intel_encoders_disable.isra.107+0x197/0x310 [i915]
[ 45.065498] haswell_crtc_disable+0xbe/0x400 [i915]
[ 45.065622] ? i9xx_disable_plane+0x1c0/0x3e0 [i915]
[ 45.065750] intel_atomic_commit_tail+0x74e/0x3e60 [i915]
[ 45.065884] ? intel_pre_plane_update+0xbc0/0xbc0 [i915]
[ 45.065968] ? drm_atomic_helper_swap_state+0x88b/0x1d90 [drm_kms_helper]
[ 45.066054] ? kasan_check_write+0x14/0x20
[ 45.066165] ? i915_gem_track_fb+0x13a/0x330 [i915]
[ 45.066277] ? i915_sw_fence_complete+0xe9/0x140 [i915]
[ 45.066406] ? __i915_sw_fence_complete+0xc50/0xc50 [i915]
[ 45.066540] intel_atomic_commit+0x72e/0xef0 [i915]
[ 45.066635] ? drm_dev_dbg+0x200/0x200 [drm]
[ 45.066764] ? intel_atomic_commit_tail+0x3e60/0x3e60 [i915]
[ 45.066898] ? intel_atomic_commit_tail+0x3e60/0x3e60 [i915]
[ 45.067001] drm_atomic_commit+0xc4/0xf0 [drm]
[ 45.067074] restore_fbdev_mode_atomic+0x562/0x780 [drm_kms_helper]
[ 45.067166] ? drm_fb_helper_debug_leave+0x690/0x690 [drm_kms_helper]
[ 45.067249] ? kasan_check_read+0x11/0x20
[ 45.067324] restore_fbdev_mode+0x127/0x4b0 [drm_kms_helper]
[ 45.067364] ? kasan_check_read+0x11/0x20
[ 45.067406] drm_fb_helper_restore_fbdev_mode_unlocked+0x164/0x200 [drm_kms_helper]
[ 45.067462] ? drm_fb_helper_hotplug_event+0x30/0x30 [drm_kms_helper]
[ 45.067508] ? kasan_check_write+0x14/0x20
[ 45.070360] ? mutex_unlock+0x22/0x40
[ 45.073748] drm_fb_helper_set_par+0xb2/0xf0 [drm_kms_helper]
[ 45.075846] drm_fb_helper_hotplug_event.part.33+0x1cd/0x290 [drm_kms_helper]
[ 45.078088] drm_fb_helper_hotplug_event+0x1c/0x30 [drm_kms_helper]
[ 45.082614] intel_fbdev_output_poll_changed+0x9f/0x140 [i915]
[ 45.087069] drm_kms_helper_hotplug_event+0x67/0x90 [drm_kms_helper]
[ 45.089319] intel_dp_mst_hotplug+0x37/0x50 [i915]
[ 45.091496] drm_dp_destroy_connector_work+0x510/0x6f0 [drm_kms_helper]
[ 45.093675] ? drm_dp_update_payload_part1+0x1220/0x1220 [drm_kms_helper]
[ 45.095851] ? kasan_check_write+0x14/0x20
[ 45.098473] ? kasan_check_read+0x11/0x20
[ 45.101155] ? strscpy+0x17c/0x530
[ 45.103808] ? __switch_to_asm+0x34/0x70
[ 45.106456] ? syscall_return_via_sysret+0xf/0x7f
[ 45.109711] ? read_word_at_a_time+0x20/0x20
[ 45.113138] ? __switch_to_asm+0x40/0x70
[ 45.116529] ? __switch_to_asm+0x34/0x70
[ 45.119891] ? __switch_to_asm+0x40/0x70
[ 45.123224] ? __switch_to_asm+0x34/0x70
[ 45.126540] ? __switch_to_asm+0x34/0x70
[ 45.129824] process_one_work+0x88d/0x15d0
[ 45.133172] ? pool_mayday_timeout+0x850/0x850
[ 45.136459] ? pci_mmcfg_check_reserved+0x110/0x128
[ 45.139739] ? wake_q_add+0xb0/0xb0
[ 45.143010] ? check_preempt_wakeup+0x652/0x1050
[ 45.146304] ? worker_enter_idle+0x29e/0x740
[ 45.149589] ? __schedule+0x1ec0/0x1ec0
[ 45.152937] ? kasan_check_read+0x11/0x20
[ 45.156179] ? _raw_spin_lock_irq+0xa3/0x130
[ 45.159382] ? _raw_read_unlock_irqrestore+0x30/0x30
[ 45.162542] ? kasan_check_write+0x14/0x20
[ 45.165657] worker_thread+0x1a5/0x1470
[ 45.168725] ? set_load_weight+0x2e0/0x2e0
[ 45.171755] ? process_one_work+0x15d0/0x15d0
[ 45.174806] ? __switch_to_asm+0x34/0x70
[ 45.177645] ? __switch_to_asm+0x40/0x70
[ 45.180323] ? __switch_to_asm+0x34/0x70
[ 45.182936] ? __switch_to_asm+0x40/0x70
[ 45.185539] ? __switch_to_asm+0x34/0x70
[ 45.188100] ? __switch_to_asm+0x40/0x70
[ 45.190628] ? __schedule+0x7d4/0x1ec0
[ 45.193143] ? save_stack+0xa9/0xd0
[ 45.195632] ? kasan_check_write+0x10/0x20
[ 45.198162] ? kasan_kmalloc+0xc4/0xe0
[ 45.200609] ? kmem_cache_alloc_trace+0xdd/0x190
[ 45.203046] ? kthread+0x9f/0x3b0
[ 45.205470] ? ret_from_fork+0x35/0x40
[ 45.207876] ? unwind_next_frame+0x43/0x50
[ 45.210273] ? __save_stack_trace+0x82/0x100
[ 45.212658] ? deactivate_slab.isra.67+0x3d4/0x580
[ 45.215026] ? default_wake_function+0x35/0x50
[ 45.217399] ? kasan_check_read+0x11/0x20
[ 45.219825] ? _raw_spin_lock_irqsave+0xae/0x140
[ 45.222174] ? __lock_text_start+0x8/0x8
[ 45.224521] ? replenish_dl_entity.cold.62+0x4f/0x4f
[ 45.226868] ? __kthread_parkme+0x87/0xf0
[ 45.229200] kthread+0x2f7/0x3b0
[ 45.231557] ? process_one_work+0x15d0/0x15d0
[ 45.233923] ? kthread_park+0x120/0x120
[ 45.236249] ret_from_fork+0x35/0x40
[ 45.240875] Allocated by task 242:
[ 45.243136] save_stack+0x43/0xd0
[ 45.245385] kasan_kmalloc+0xc4/0xe0
[ 45.247597] kmem_cache_alloc_trace+0xdd/0x190
[ 45.249793] drm_dp_add_port+0x1e0/0x2170 [drm_kms_helper]
[ 45.252000] drm_dp_send_link_address+0x4a7/0x740 [drm_kms_helper]
[ 45.254389] drm_dp_check_and_send_link_address+0x1a7/0x210 [drm_kms_helper]
[ 45.256803] drm_dp_mst_link_probe_work+0x6f/0xb0 [drm_kms_helper]
[ 45.259200] process_one_work+0x88d/0x15d0
[ 45.261597] worker_thread+0x1a5/0x1470
[ 45.264038] kthread+0x2f7/0x3b0
[ 45.266371] ret_from_fork+0x35/0x40
[ 45.270937] Freed by task 53:
[ 45.273170] save_stack+0x43/0xd0
[ 45.275382] __kasan_slab_free+0x139/0x190
[ 45.277604] kasan_slab_free+0xe/0x10
[ 45.279826] kfree+0x99/0x1b0
[ 45.282044] drm_dp_free_mst_port+0x4a/0x60 [drm_kms_helper]
[ 45.284330] drm_dp_destroy_connector_work+0x43e/0x6f0 [drm_kms_helper]
[ 45.286660] process_one_work+0x88d/0x15d0
[ 45.288934] worker_thread+0x1a5/0x1470
[ 45.291231] kthread+0x2f7/0x3b0
[ 45.293547] ret_from_fork+0x35/0x40
[ 45.298206] The buggy address belongs to the object at ffff8882b4b70968
which belongs to the cache kmalloc-2k of size 2048
[ 45.303047] The buggy address is located 0 bytes inside of
2048-byte region [ffff8882b4b70968, ffff8882b4b71168)
[ 45.308010] The buggy address belongs to the page:
[ 45.310477] page:ffffea000ad2dc00 count:1 mapcount:0 mapping:ffff8882c080cf40 index:0x0 compound_mapcount: 0
[ 45.313051] flags: 0x8000000000010200(slab|head)
[ 45.315635] raw: 8000000000010200 ffffea000aac2808 ffffea000abe8608 ffff8882c080cf40
[ 45.318300] raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000
[ 45.320966] page dumped because: kasan: bad access detected
[ 45.326312] Memory state around the buggy address:
[ 45.329085] ffff8882b4b70800: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 45.331845] ffff8882b4b70880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 45.334584] >ffff8882b4b70900: fc fc fc fc fc fc fc fc fc fc fc fc fc fb fb fb
[ 45.337302] ^
[ 45.340061] ffff8882b4b70980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 45.342910] ffff8882b4b70a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 45.345748] ==================================================================
So, this definitely isn't a fix that we want. This being said; there's
no real easy fix for this problem because of some of the catch-22's of
the MST helpers current design. For starters; we always need to validate
a port with drm_dp_get_validated_port_ref(), but validation relies on
the lifetime of the port in the actual topology. So once the port is
gone, it can't be validated again.
If we were to try to make the payload helpers not use port validation,
then we'd cause another problem: if the port isn't validated, it could
be freed and we'd just start causing more KASAN issues. There are
already hacks that attempt to workaround this in
drm_dp_mst_destroy_connector_work() by re-initializing the kref so that
it can be used again and it's memory can be freed once the VCPI helpers
finish removing the port's respective payloads. But none of these really
do anything helpful since the port still can't be validated since it's
gone from the topology. Also, that workaround is immensely confusing to
read through.
What really needs to be done in order to fix this is to teach DRM how to
track the lifetime of the structs for MST ports and branch devices
separately from their lifetime in the actual topology. Simply put; this
means having two different krefs-one that removes the port/branch device
from the topology, and one that finally calls kfree(). This would let us
simplify things, since we'd now be able to keep ports around without
having to keep them in the topology at the same time, which is exactly
what we need in order to teach our VCPI helpers to only validate ports
when it's actually necessary without running the risk of trying to use
unallocated memory.
Such a fix is on it's way, but for now let's play it safe and just
revert this. If this bug has been around for well over a year, we can
wait a little while to get an actual proper fix here.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: c54c7374ff ("drm/dp_mst: Skip validating ports during destruction, just ref")
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sean Paul <sean@poorly.run>
Cc: Jerry Zuo <Jerry.Zuo@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: stable@vger.kernel.org # v4.6+
Acked-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20181128210005.24434-1-lyude@redhat.com
Pull networking fixes from David Miller:
1) ARM64 JIT fixes for subprog handling from Daniel Borkmann.
2) Various sparc64 JIT bug fixes (fused branch convergance, frame
pointer usage detection logic, PSEODU call argument handling).
3) Fix to use BH locking in nf_conncount, from Taehee Yoo.
4) Fix race of TX skb freeing in ipheth driver, from Bernd Eckstein.
5) Handle return value of TX NAPI completion properly in lan743x
driver, from Bryan Whitehead.
6) MAC filter deletion in i40e driver clears wrong state bit, from
Lihong Yang.
7) Fix use after free in rionet driver, from Pan Bian.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (53 commits)
s390/qeth: fix length check in SNMP processing
net: hisilicon: remove unexpected free_netdev
rapidio/rionet: do not free skb before reading its length
i40e: fix kerneldoc for xsk methods
ixgbe: recognize 1000BaseLX SFP modules as 1Gbps
i40e: Fix deletion of MAC filters
igb: fix uninitialized variables
netfilter: nf_tables: deactivate expressions in rule replecement routine
lan743x: Enable driver to work with LAN7431
tipc: fix lockdep warning during node delete
lan743x: fix return value for lan743x_tx_napi_poll
net: via: via-velocity: fix spelling mistake "alignement" -> "alignment"
qed: fix spelling mistake "attnetion" -> "attention"
net: thunderx: fix NULL pointer dereference in nic_remove
sctp: increase sk_wmem_alloc when head->truesize is increased
firestream: fix spelling mistake: "Inititing" -> "Initializing"
net: phy: add workaround for issue where PHY driver doesn't bind to the device
usbnet: ipheth: fix potential recvmsg bug and recvmsg bug 2
sparc: Adjust bpf JIT prologue for PSEUDO calls.
bpf, doc: add entries of who looks over which jits
...
- Fix kernel exception on userspace access to a currently disabled
coprocessor.
- Fix coprocessor data saving/restoring in configurations with multiple
coprocessors.
- Fix ptrace access to coprocessor data on configurations with multiple
coprocessors with high alignment requirements.
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Merge tag 'xtensa-20181128' of git://github.com/jcmvbkbc/linux-xtensa
Pull Xtensa fixes from Max Filippov:
- fix kernel exception on userspace access to a currently disabled
coprocessor
- fix coprocessor data saving/restoring in configurations with multiple
coprocessors
- fix ptrace access to coprocessor data on configurations with multiple
coprocessors with high alignment requirements
* tag 'xtensa-20181128' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: fix coprocessor part of ptrace_{get,set}xregs
xtensa: fix coprocessor context offset definitions
xtensa: enable coprocessors that are being flushed
Driver shouldn't try to access any GFX registers until RLC is idle.
During the test, it took 12 seconds for RLC to clear the BUSY bit
in RLC_GPM_STAT register which is un-acceptable for driver.
As per RLC engineer, it would take RLC Ucode less than 10,000 GFXCLK
cycles to finish its critical section. In a lowest 300M enginer clock
setting(default from vbios), 50 us delay is enough.
This commit fix the hang when RLC introduce the work around for XGMI
which requires more cycles to setup more registers than normal
Signed-off-by: shaoyunl <shaoyun.liu@amd.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Don't bounce back to the root level for fragment processing, because
huge pages are not supported at that level. This is unlikely to happen
with the default VM size on Vega, but can be exposed by limiting the
VM size with the amdgpu.vm_size module parameter.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Avoid potential integer overflows with left shift in huge-page mapping
code by casting the operand to uin64_t first.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Jeff Kirsher says:
====================
Intel Wired LAN Driver Fixes 2018-11-28
This series contains fixes to igb, ixgbe and i40e.
Yunjian Wang from Huawei resolves a variable that could potentially be
NULL before it is used.
Lihong fixes an i40e issue which goes back to 4.17 kernels, where
deleting any of the MAC filters was causing the incorrect syncing for
the PF.
Josh Elsasser caught that there were missing enum values in the link
capabilities for x550 devices, which was preventing link for 1000BaseLX
SFP modules.
Jan fixes the function header comments for XSK methods.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The response for a SNMP request can consist of multiple parts, which
the cmd callback stages into a kernel buffer until all parts have been
received. If the callback detects that the staging buffer provides
insufficient space, it bails out with error.
This processing is buggy for the first part of the response - while it
initially checks for a length of 'data_len', it later copies an
additional amount of 'offsetof(struct qeth_snmp_cmd, data)' bytes.
Fix the calculation of 'data_len' for the first part of the response.
This also nicely cleans up the memcpy code.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Disable BH while holding list spinlock in nf_conncount, from
Taehee Yoo.
2) List corruption in nf_conncount, also from Taehee.
3) Fix race that results in leaving around an empty list node in
nf_conncount, from Taehee Yoo.
4) Proper chain handling for inactive chains from the commit path,
from Florian Westphal. This includes a selftest for this.
5) Do duplicate rule handles when replacing rules, also from Florian.
6) Remove net_exit path in xt_RATEEST that results in splat, from Taehee.
7) Possible use-after-free in nft_compat when releasing extensions.
From Florian.
8) Memory leak in xt_hashlimit, from Taehee.
9) Call ip_vs_dst_notifier after ipv6_dev_notf, from Xin Long.
10) Fix cttimeout with udplite and gre, from Florian.
11) Preserve oif for IPv6 link-local generated traffic from mangle
table, from Alin Nastac.
12) Missing error handling in masquerade notifiers, from Taehee Yoo.
13) Use mutex to protect registration/unregistration of masquerade
extensions in order to prevent a race, from Taehee.
14) Incorrect condition check in tree_nodes_free(), also from Taehee.
15) Fix chain counter leak in rule replacement path, from Taehee.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The net device ndev is freed via free_netdev when failing to register
the device. The control flow then jumps to the error handling code
block. ndev is used and freed again. Resulting in a use-after-free bug.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb is freed via dev_kfree_skb_any, however, skb->len is read then. This
may result in a use-after-free bug.
Fixes: e6161d6426 ("rapidio/rionet: rework driver initialization and removal")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One method, xsk_umem_setup, had an incorrect kernel doc
description, which has been corrected.
Also fixes small typos found in the comments.
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
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Merge tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Some of these bugs are being hit during testing so we'd like to get
them merged, otherwise there are usual stability fixes for stable
trees"
* tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: relocation: set trans to be NULL after ending transaction
Btrfs: fix race between enabling quotas and subvolume creation
Btrfs: send, fix infinite loop due to directory rename dependencies
Btrfs: ensure path name is null terminated at btrfs_control_ioctl
Btrfs: fix rare chances for data loss when doing a fast fsync
btrfs: Always try all copies when reading extent buffers
A few driver specific fixes here, nothing big or that stands out for
anyone other than the driver users.
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Merge tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A few driver specific fixes here, nothing big or that stands out for
anyone other than the driver users.
The omap2-mcspi fix is for issues that started showing up with a
change in defconfig in this release to make cpuidle get turned on by
default"
* tag 'spi-fix-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: omap2-mcspi: Add missing suspend and resume calls
spi: mediatek: use correct mata->xfer_len when in fifo transfer
spi: uniphier: fix incorrect property items
Add the two 1000BaseLX enum values to the X550's check for 1Gbps modules,
allowing the core driver code to establish a link over this SFP type.
This is done by the out-of-tree driver but the fix wasn't in mainline.
Fixes: e23f333678 ("ixgbe: Fix 1G and 10G link stability for X550EM_x SFP+”)
Fixes: 6a14ee0cfb ("ixgbe: Add X550 support function pointers")
Signed-off-by: Josh Elsasser <jelsasser@appneta.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
merge window.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"Bugfixes, many of them reported by syzkaller and mostly predating the
merge window"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: svm: Ensure an IBPB on all affected CPUs when freeing a vmcb
kvm: mmu: Fix race in emulated page table writes
KVM: nVMX: vmcs12 revision_id is always VMCS12_REVISION even when copied from eVMCS
KVM: nVMX: Verify eVMCS revision id match supported eVMCS version on eVMCS VMPTRLD
KVM: nVMX/nSVM: Fix bug which sets vcpu->arch.tsc_offset to L1 tsc_offset
x86/kvm/vmx: fix old-style function declaration
KVM: x86: fix empty-body warnings
KVM: VMX: Update shared MSRs to be saved/restored on MSR_EFER.LMA changes
KVM: x86: Fix kernel info-leak in KVM_HC_CLOCK_PAIRING hypercall
KVM: nVMX: Fix kernel info-leak when enabling KVM_CAP_HYPERV_ENLIGHTENED_VMCS more than once
svm: Add mutex_lock to protect apic_access_page_done on AMD systems
KVM: X86: Fix scan ioapic use-before-initialization
KVM: LAPIC: Fix pv ipis use-before-initialization
KVM: VMX: re-add ple_gap module parameter
KVM: PPC: Book3S HV: Fix handling for interrupted H_ENTER_NESTED
In __i40e_del_filter function, the flag __I40E_MACVLAN_SYNC_PENDING for
the PF state is wrongly set for the VSI. Deleting any of the MAC filters
has caused the incorrect syncing for the PF. Fix it by setting this state
flag to the intended PF.
CC: stable <stable@vger.kernel.org>
Signed-off-by: Lihong Yang <lihong.yang@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This patch fixes the variable 'phy_word' may be used uninitialized.
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
[Description]
In a heavily loaded system where the system pagecache is nearing memory
limits and fscache is enabled, pages can be leaked by fscache while trying
read pages from cachefiles backend. This can happen because two
applications can be reading same page from a single mount, two threads can
be trying to read the backing page at same time. This results in one of
the threads finding that a page for the backing file or netfs file is
already in the radix tree. During the error handling cachefiles does not
clean up the reference on backing page, leading to page leak.
[Fix]
The fix is straightforward, to decrement the reference when error is
encountered.
[dhowells: Note that I've removed the clearance and put of newpage as
they aren't attested in the commit message and don't appear to actually
achieve anything since a new page is only allocated is newpage!=NULL and
any residual new page is cleared before returning.]
[Testing]
I have tested the fix using following method for 12+ hrs.
1) mkdir -p /mnt/nfs ; mount -o vers=3,fsc <server_ip>:/export /mnt/nfs
2) create 10000 files of 2.8MB in a NFS mount.
3) start a thread to simulate heavy VM presssure
(while true ; do echo 3 > /proc/sys/vm/drop_caches ; sleep 1 ; done)&
4) start multiple parallel reader for data set at same time
find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
..
..
find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
5) finally check using cat /proc/fs/fscache/stats | grep -i pages ;
free -h , cat /proc/meminfo and page-types -r -b lru
to ensure all pages are freed.
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Shantanu Goel <sgoel01@yahoo.com>
Signed-off-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
[dja: forward ported to current upstream]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the size of the buffer allocated to store the in-memory BBT.
This bug was previously hidden by a different bug, that was fixed in
commit d098093ba0 ("mtd: nand: Fix nanddev_neraseblocks()").
Fixes: 9c3736a3de ("mtd: nand: Add core infrastructure to deal with NAND devices")
Cc: <stable@vger.kernel.org>
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
The code in fscache_retrieval_complete is using atomic_sub followed by an
atomic_read:
atomic_sub(n_pages, &op->n_pages);
if (atomic_read(&op->n_pages) <= 0)
fscache_op_complete(&op->op, true);
This causes two threads doing a decrement of n_pages to race with each
other seeing the op->refcount 0 at same time - and they end up calling
fscache_op_complete() in both the threads leading to an assertion failure.
Fix this by using atomic_sub_return_relaxed() instead of two calls. Note
that I'm using 'relaxed' rather than, say, 'release' as there aren't
multiple variables that appear to need ordering across the release.
The oops looks something like:
FS-Cache: Assertion failed
FS-Cache: 0 > 0 is false
...
kernel BUG at /usr/src/linux-4.4.0/fs/fscache/operation.c:449!
...
Workqueue: fscache_operation fscache_op_work_func [fscache]
...
RIP: 0010:[<ffffffffc037eacd>] fscache_op_complete+0x10d/0x180 [fscache]
...
Call Trace:
[<ffffffffc1464cf9>] cachefiles_read_copier+0x3a9/0x410 [cachefiles]
[<ffffffffc037e272>] fscache_op_work_func+0x22/0x50 [fscache]
[<ffffffff81096da0>] process_one_work+0x150/0x3f0
[<ffffffff8109751a>] worker_thread+0x11a/0x470
[<ffffffff81808e59>] ? __schedule+0x359/0x980
[<ffffffff81097400>] ? rescuer_thread+0x310/0x310
[<ffffffff8109cdd6>] kthread+0xd6/0xf0
[<ffffffff8109cd00>] ? kthread_park+0x60/0x60
[<ffffffff8180d0cf>] ret_from_fork+0x3f/0x70
[<ffffffff8109cd00>] ? kthread_park+0x60/0x60
This seen this in 4.4.x kernels and the same bug affects fscache in latest
upstreams kernels.
Fixes: 1bb4b7f98f ("FS-Cache: The retrieval remaining-pages counter needs to be atomic_t")
Signed-off-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
If cachefiles gets an error other then ENOENT when trying to look up an
object in the cache (in this case, EACCES), the object state machine will
eventually transition to the DROP_OBJECT state.
This state invokes fscache_drop_object() which tries to sync the auxiliary
data with the cache (this is done lazily since commit 402cb8dda9) on an
incomplete cache object struct.
The problem comes when cachefiles_update_object_xattr() is called to
rewrite the xattr holding the data. There's an assertion there that the
cache object points to a dentry as we're going to update its xattr. The
assertion trips, however, as dentry didn't get set.
Fix the problem by skipping the update in cachefiles if the object doesn't
refer to a dentry. A better way to do it could be to skip the update from
the DROP_OBJECT state handler in fscache, but that might deny the cache the
opportunity to update intermediate state.
If this error occurs, the kernel log includes lines that look like the
following:
CacheFiles: Lookup failed error -13
CacheFiles:
CacheFiles: Assertion failed
------------[ cut here ]------------
kernel BUG at fs/cachefiles/xattr.c:138!
...
Workqueue: fscache_object fscache_object_work_func [fscache]
RIP: 0010:cachefiles_update_object_xattr.cold.4+0x18/0x1a [cachefiles]
...
Call Trace:
cachefiles_update_object+0xdd/0x1c0 [cachefiles]
fscache_update_aux_data+0x23/0x30 [fscache]
fscache_drop_object+0x18e/0x1c0 [fscache]
fscache_object_work_func+0x74/0x2b0 [fscache]
process_one_work+0x18d/0x340
worker_thread+0x2e/0x390
? pwq_unbound_release_workfn+0xd0/0xd0
kthread+0x112/0x130
? kthread_bind+0x30/0x30
ret_from_fork+0x35/0x40
Note that there are actually two issues here: (1) EACCES happened on a
cache object and (2) an oops occurred. I think that the second is a
consequence of the first (it certainly looks like it ought to be). This
patch only deals with the second.
Fixes: 402cb8dda9 ("fscache: Attach the index key and aux data to the cookie")
Reported-by: Zhibin Li <zhibli@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Provide the possibility to enable IBPB always in combination with 'prctl'
and 'seccomp'.
Add the extra command line options and rework the IBPB selection to
evaluate the command instead of the mode selected by the STIPB switch case.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185006.144047038@linutronix.de
If 'prctl' mode of user space protection from spectre v2 is selected
on the kernel command-line, STIBP and IBPB are applied on tasks which
restrict their indirect branch speculation via prctl.
SECCOMP enables the SSBD mitigation for sandboxed tasks already, so it
makes sense to prevent spectre v2 user space to user space attacks as
well.
The Intel mitigation guide documents how STIPB works:
Setting bit 1 (STIBP) of the IA32_SPEC_CTRL MSR on a logical processor
prevents the predicted targets of indirect branches on any logical
processor of that core from being controlled by software that executes
(or executed previously) on another logical processor of the same core.
Ergo setting STIBP protects the task itself from being attacked from a task
running on a different hyper-thread and protects the tasks running on
different hyper-threads from being attacked.
While the document suggests that the branch predictors are shielded between
the logical processors, the observed performance regressions suggest that
STIBP simply disables the branch predictor more or less completely. Of
course the document wording is vague, but the fact that there is also no
requirement for issuing IBPB when STIBP is used points clearly in that
direction. The kernel still issues IBPB even when STIBP is used until Intel
clarifies the whole mechanism.
IBPB is issued when the task switches out, so malicious sandbox code cannot
mistrain the branch predictor for the next user space task on the same
logical processor.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185006.051663132@linutronix.de
Now that all prerequisites are in place:
- Add the prctl command line option
- Default the 'auto' mode to 'prctl'
- When SMT state changes, update the static key which controls the
conditional STIBP evaluation on context switch.
- At init update the static key which controls the conditional IBPB
evaluation on context switch.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.958421388@linutronix.de
Add the PR_SPEC_INDIRECT_BRANCH option for the PR_GET_SPECULATION_CTRL and
PR_SET_SPECULATION_CTRL prctls to allow fine grained per task control of
indirect branch speculation via STIBP and IBPB.
Invocations:
Check indirect branch speculation status with
- prctl(PR_GET_SPECULATION_CTRL, PR_SPEC_INDIRECT_BRANCH, 0, 0, 0);
Enable indirect branch speculation with
- prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_INDIRECT_BRANCH, PR_SPEC_ENABLE, 0, 0);
Disable indirect branch speculation with
- prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_INDIRECT_BRANCH, PR_SPEC_DISABLE, 0, 0);
Force disable indirect branch speculation with
- prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_INDIRECT_BRANCH, PR_SPEC_FORCE_DISABLE, 0, 0);
See Documentation/userspace-api/spec_ctrl.rst.
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.866780996@linutronix.de
The upcoming fine grained per task STIBP control needs to be updated on CPU
hotplug as well.
Split out the code which controls the strict mode so the prctl control code
can be added later. Mark the SMP function call argument __unused while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.759457117@linutronix.de
The seccomp speculation control operates on all tasks of a process, but
only the current task of a process can update the MSR immediately. For the
other threads the update is deferred to the next context switch.
This creates the following situation with Process A and B:
Process A task 2 and Process B task 1 are pinned on CPU1. Process A task 2
does not have the speculation control TIF bit set. Process B task 1 has the
speculation control TIF bit set.
CPU0 CPU1
MSR bit is set
ProcB.T1 schedules out
ProcA.T2 schedules in
MSR bit is cleared
ProcA.T1
seccomp_update()
set TIF bit on ProcA.T2
ProcB.T1 schedules in
MSR is not updated <-- FAIL
This happens because the context switch code tries to avoid the MSR update
if the speculation control TIF bits of the incoming and the outgoing task
are the same. In the worst case ProcB.T1 and ProcA.T2 are the only tasks
scheduling back and forth on CPU1, which keeps the MSR stale forever.
In theory this could be remedied by IPIs, but chasing the remote task which
could be migrated is complex and full of races.
The straight forward solution is to avoid the asychronous update of the TIF
bit and defer it to the next context switch. The speculation control state
is stored in task_struct::atomic_flags by the prctl and seccomp updates
already.
Add a new TIF_SPEC_FORCE_UPDATE bit and set this after updating the
atomic_flags. Check the bit on context switch and force a synchronous
update of the speculation control if set. Use the same mechanism for
updating the current task.
Reported-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1811272247140.1875@nanos.tec.linutronix.de
The update of the TIF_SSBD flag and the conditional speculation control MSR
update is done in the ssb_prctl_set() function directly. The upcoming prctl
support for controlling indirect branch speculation via STIBP needs the
same mechanism.
Split the code out and make it reusable. Reword the comment about updates
for other tasks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.652305076@linutronix.de
The IBPB control code in x86 removed the usage. Remove the functionality
which was introduced for this.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.559149393@linutronix.de
The IBPB speculation barrier is issued from switch_mm() when the kernel
switches to a user space task with a different mm than the user space task
which ran last on the same CPU.
An additional optimization is to avoid IBPB when the incoming task can be
ptraced by the outgoing task. This optimization only works when switching
directly between two user space tasks. When switching from a kernel task to
a user space task the optimization fails because the previous task cannot
be accessed anymore. So for quite some scenarios the optimization is just
adding overhead.
The upcoming conditional IBPB support will issue IBPB only for user space
tasks which have the TIF_SPEC_IB bit set. This requires to handle the
following cases:
1) Switch from a user space task (potential attacker) which has
TIF_SPEC_IB set to a user space task (potential victim) which has
TIF_SPEC_IB not set.
2) Switch from a user space task (potential attacker) which has
TIF_SPEC_IB not set to a user space task (potential victim) which has
TIF_SPEC_IB set.
This needs to be optimized for the case where the IBPB can be avoided when
only kernel threads ran in between user space tasks which belong to the
same process.
The current check whether two tasks belong to the same context is using the
tasks context id. While correct, it's simpler to use the mm pointer because
it allows to mangle the TIF_SPEC_IB bit into it. The context id based
mechanism requires extra storage, which creates worse code.
When a task is scheduled out its TIF_SPEC_IB bit is mangled as bit 0 into
the per CPU storage which is used to track the last user space mm which was
running on a CPU. This bit can be used together with the TIF_SPEC_IB bit of
the incoming task to make the decision whether IBPB needs to be issued or
not to cover the two cases above.
As conditional IBPB is going to be the default, remove the dubious ptrace
check for the IBPB always case and simply issue IBPB always when the
process changes.
Move the storage to a different place in the struct as the original one
created a hole.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.466447057@linutronix.de
The TIF_SPEC_IB bit does not need to be evaluated in the decision to invoke
__switch_to_xtra() when:
- CONFIG_SMP is disabled
- The conditional STIPB mode is disabled
The TIF_SPEC_IB bit still controls IBPB in both cases so the TIF work mask
checks might invoke __switch_to_xtra() for nothing if TIF_SPEC_IB is the
only set bit in the work masks.
Optimize it out by masking the bit at compile time for CONFIG_SMP=n and at
run time when the static key controlling the conditional STIBP mode is
disabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.374062201@linutronix.de
Move the conditional invocation of __switch_to_xtra() into an inline
function so the logic can be shared between 32 and 64 bit.
Remove the handthrough of the TSS pointer and retrieve the pointer directly
in the bitmap handling function. Use this_cpu_ptr() instead of the
per_cpu() indirection.
This is a preparatory change so integration of conditional indirect branch
speculation optimization happens only in one place.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.280855518@linutronix.de
To avoid the overhead of STIBP always on, it's necessary to allow per task
control of STIBP.
Add a new task flag TIF_SPEC_IB and evaluate it during context switch if
SMT is active and flag evaluation is enabled by the speculation control
code. Add the conditional evaluation to x86_virt_spec_ctrl() as well so the
guest/host switch works properly.
This has no effect because TIF_SPEC_IB cannot be set yet and the static key
which controls evaluation is off. Preparatory patch for adding the control
code.
[ tglx: Simplify the context switch logic and make the TIF evaluation
depend on SMP=y and on the static key controlling the conditional
update. Rename it to TIF_SPEC_IB because it controls both STIBP and
IBPB ]
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.176917199@linutronix.de
Pan Bian