wilc_wlan_handle_isr_ext() takes the RX transfer size from the
device-reported interrupt status register (a 15-bit field shifted left by 2,
up to 131068 bytes) and reads that many bytes from the device into
rx_buffer, which is only WILC_RX_BUFF_SIZE (96K) large. The wrap
check only handles the current offset; the size itself is never
compared against the buffer, so a bogus SDIO device can make the driver
OOB-write rx_buffer by up to ~32K with data it controls.
The oversized transfer also leaves rx_buffer_offset past the end of
the buffer, after which the unsigned wrap check stops working and
the overflow can repeat.
Drop any transfer whose size exceeds the RX buffer, acknowledging
the data interrupt and re-arming the RX engine so the bogus frame is
discarded and reception can continue. This also restores the
rx_buffer_offset <= WILC_RX_BUFF_SIZE invariant the wrap check
relies on.
This is not expected to change driver behavior in most cases:
without this check, an oversized transfer would most likely
corrupt neighboring kernel memory instead of completing anyway, and
the drop path performs the same interrupt acknowledgment and RX
engine re-arming as the normal path, so subsequent transfers are
received unaffected.
Discovered by Atuin - Automated Vulnerability Discovery Engine.
Fixes: c5c77ba18e ("staging: wilc1000: Add SDIO/SPI 802.11 driver")
Cc: stable@vger.kernel.org
Assisted-by: LLM
Signed-off-by: Tianchu Chen <flynnnchen@tencent.com>
Link: https://patch.msgid.link/7c971924c6bdccf6c2f75704a5a746e9303aaf64@linux.dev
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a key is removed (data == NULL), rsi_hal_load_key() runs:
memset(&set_key[FRAME_DESC_SZ], 0, frame_len - FRAME_DESC_SZ);
set_key is a struct rsi_set_key *, so the subscript is scaled by
sizeof(struct rsi_set_key) (160 bytes): &set_key[FRAME_DESC_SZ] is
skb->data + 2560, and the memset writes 144 zero bytes starting
2.4KB past the end of the 160-byte skb data buffer, corrupting
unrelated heap objects. The intended byte offset would have been
(u8 *)set_key + FRAME_DESC_SZ.
The write fires on every DISABLE_KEY callback, so plain disconnects,
roams and interface teardowns trigger it on real networks.
The memset is redundant: the whole buffer is zeroed right after
allocation, so the frame sent to the device is byte-identical
without it. Drop the else branch; normal operation is unaffected.
Discovered by Atuin - Automated Vulnerability Discovery Engine.
Fixes: dad0d04fa7 ("rsi: Add RS9113 wireless driver")
Cc: stable@vger.kernel.org
Assisted-by: LLM
Signed-off-by: Tianchu Chen <flynnnchen@tencent.com>
Link: https://patch.msgid.link/90bb2b07007942064c04aa3729cedd9eb1e930b1@linux.dev
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a network namespace is destroyed, cfg80211_pernet_exit() moves any
wiphy back to the initial namespace, and just warns if that fails. But
moving an interface can fail (due to allocation failures), and then the
wiphy is left behind with a garbage netns pointer:
Kernel mode fault at addr 0x30
genlmsg_multicast_netns.constprop.0+0x46/0xcf [cfg80211]
nl80211_notify_wiphy+0xcd/0xe8 [cfg80211]
wiphy_unregister+0x169/0x3fc [cfg80211]
Note that commit debac3a20d ("net: Remove conflicting altnames for
dying netns in __dev_change_net_namespace().") fixed another path
that could reach it without allocation failures.
Remove interfaces that cannot be moved instead of failing the switch,
so that the wiphy always ends up in the initial namespace. In this
case the netdev core will unregister the interfaces anyway.
Assisted-by: LLM
Reported-by: syzbot+c5f8a81e794d4a4f2014@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c5f8a81e794d4a4f2014
Fixes: 463d018323 ("cfg80211: make aware of net namespaces")
Link: https://patch.msgid.link/20260904170220.7f3edc6d9992.I5e57921011244d3d8ef14d89e738aa19a5d972a0@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211 only removes vifs from the local->interfaces list when
an interface is removed via ieee80211_if_remove(), before it
unregisters the netdev. However, it's possible for a netdev to
be unregistered without going through that: When the netns that
holds the wiphy is destroyed, the wiphy is supposed to move to
the init_ns, but that can run into allocation failures.
Then, mac80211 has an interface listed that doesn't exist, and
will eventually hit
BUG: failure at net/wireless/core.h:141/wiphy_to_rdev()!
...
_cfg80211_unregister_wdev+0x24/0x36a [cfg80211]
cfg80211_unregister_wdev+0x15/0x1d [cfg80211]
ieee80211_remove_interfaces+0x1ff/0x257 [mac80211]
ieee80211_unregister_hw+0x73/0x1d1 [mac80211]
mac80211_hwsim_del_radio+0x114/0x166 [mac80211_hwsim]
Remove the interface from the list in ->ndo_uninit if it's still
around to avoid this.
Assisted-by: LLM
Fixes: 463d018323 ("cfg80211: make aware of net namespaces")
Link: https://patch.msgid.link/20260904170220.038ad73e6c04.I990abca78483e058746b6f42b4796717c3028164@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Switching a wiphy's netns has to clear netns_immutable before moving
interfaces, but then if any of the interfaces fails to move, it gets
netns_immutable cleared forever. Then userspace can move it by itself,
breaking the assumption that they all move together.
Fix the order here and always reset netns_immutable after attempting
the move.
Assisted-by: LLM
Fixes: 463d018323 ("cfg80211: make aware of net namespaces")
Link: https://patch.msgid.link/20260904170220.7ea88157dcbc.Id868585a790be8b9ece9b39b0db464a5963faaf3@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When the first interface comes up, the radio LED is turned on. This can
start the TPT trigger timer, which continues running.
But if bringing up the interface fails then the timer keeps running and
won't be stopped by anything, eventually it can be freed:
ODEBUG: free active (active state 0) object: ffff888127e12130 object type: timer_list hint: tpt_trig_timer+0x0/0x300 net/mac80211/led.c:145
WARNING: CPU: 0 PID: 5923 at lib/debugobjects.c:612 debug_print_object+0x1a2/0x2b0
debug_check_no_obj_freed+0x4b7/0x600 lib/debugobjects.c:1129
kfree+0x436/0x670 mm/slub.c:6818
ieee80211_led_exit+0x162/0x1c0 net/mac80211/led.c:210
ieee80211_unregister_hw+0x27e/0x3a0 net/mac80211/main.c:1706
rt2x00lib_remove_dev+0x55b/0x670
Undo the LED state in the error path.
Assisted-by: LLM
Fixes: 67408c8c7b ("mac80211: selective throughput LED trigger active")
Reported-by: syzbot+e84ecca6d1fa09a9b3d9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=e84ecca6d1fa09a9b3d9
Link: https://patch.msgid.link/20260904165722.044aa432f873.I601a67a2cd558b8ef8416a07554ae7efe896e9d8@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
ieee80211_start_ap() can set enable_beacon (and beacon_int) and fail
later, leaving it set forever. Scanning can then attempt to restore
beaconing on such an interface, leading to:
Oops: divide error: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:mac80211_hwsim_link_info_changed+0xca7/0xf00
Call Trace:
drv_link_info_changed+0x413/0x860 net/mac80211/driver-ops.c:495
ieee80211_link_info_change_notify+0x24b/0x3c0 net/mac80211/main.c:427
ieee80211_offchannel_return+0x381/0x580 net/mac80211/offchannel.c:160
__ieee80211_scan_completed+0x993/0xe30 net/mac80211/scan.c:519
ieee80211_scan_work+0x472/0x2010 net/mac80211/scan.c:1193
cfg80211_wiphy_work+0x2b7/0x550 net/wireless/core.c:538
in hwsim. Also, cfg80211 then allows changing the interface type,
and the off-channel path getgs confused about beaconing as well,
leading to another warning:
WARNING: net/mac80211/driver-ops.c:468 at drv_link_info_changed+0x583/0x880
ieee80211_link_info_change_notify+0x24b/0x3c0 net/mac80211/main.c:427
ieee80211_offchannel_stop_vifs+0x328/0x5c0 net/mac80211/offchannel.c:122
ieee80211_start_sw_scan net/mac80211/scan.c:583 [inline]
__ieee80211_start_scan+0xfb6/0x1af0 net/mac80211/scan.c:882
Reset the state on failures to always have it correct.
Assisted-by: LLM
Fixes: d6a8322882 ("mac80211: track enable_beacon explicitly")
Reported-by: syzbot+ca7a2759caaa6cd4e3db@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=ca7a2759caaa6cd4e3db
Reported-by: syzbot+c4686c3eb8b64032618f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c4686c3eb8b64032618f
Link: https://patch.msgid.link/20260904165722.9629429a5221.I7f599412bfe12a09d41ea4901be9ad165d07d133@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The ROC work can be pending when a scan starts (which requires
ROC list to be empty, but that's possible), and then a new ROC
can be added to the list and the work will pick it up.
Avoid starting that ROC if a scan made it between things, as
otherwise we'll hit a warning later:
WARNING: net/mac80211/offchannel.c:404 at ieee80211_start_next_roc+0x256/0x2d0
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
__ieee80211_scan_completed+0x4fd/0xe40 net/mac80211/scan.c:537
ieee80211_scan_work+0x472/0x1ff0 net/mac80211/scan.c:1193
cfg80211_wiphy_work+0x410/0x570 net/wireless/core.c:513
Assisted-by: LLM
Fixes: aaa016ccd5 ("mac80211: rewrite remain-on-channel logic")
Reported-by: syzbot+c3a167b5615df4ccd7fb@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c3a167b5615df4ccd7fb
Link: https://patch.msgid.link/20260904165722.f9d5b150edd8.I61bc9de8c8d089096ad695213b9c85c7df38c3bd@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
reg_wdev_chan_valid() returns early for any wdev that has no netdev,
which is fine for P2P originally (and later PD still), but NAN has
no netdev and yet enforcement code was added and is needed, but is
dead code right now.
Use wdev_running() instead so that netdev-less wdevs aren't skipped.
P2P/PD don't do anything in the later switch, but NAN code can now
be reached.
Assisted-by: LLM
Fixes: 0e8ec738a7 ("wifi: cfg80211: add support for NAN data interface")
Link: https://patch.msgid.link/20260904165614.6abc075b5401.Ib90696e3fa49b1698c27d64db5360d51f6f187a9@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When the IBSS is joined, we only record the BSSID/channel in the event
and look up the BSS entry when processing it. However, that's racy,
e.g. a new scan with NL80211_SCAN_FLAG_FLUSH can remove it, causing a
warning in the event work:
!bss
WARNING: net/wireless/ibss.c:37 at __cfg80211_ibss_joined+0x3d3/0x440
Workqueue: cfg80211 cfg80211_event_work
cfg80211_process_wdev_events+0x39f/0x5b0 net/wireless/util.c:1144
cfg80211_process_rdev_events+0xa1/0x110 net/wireless/util.c:1179
cfg80211_event_work+0x2f/0x40 net/wireless/core.c:393
Do the lookup early (the driver is expected to only join an IBSS that
has a BSS entry) and keep a reference to it.
Assisted-by: LLM
Fixes: 667503ddcb ("cfg80211: fix locking")
Reported-by: syzbot+7f064ba1704c2466e36d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7f064ba1704c2466e36d
Link: https://patch.msgid.link/20260904165614.f49a213f0e49.I192bfe738750ebb5f2c4faa3019a428da64cd3ec@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When an assoc AP switches to a channel that already has a BSS entry,
cfg80211_update_assoc_bss_entry() removes that entry before rehashing
the real one, since the two would otherwise collide in the BSS rbtree.
The lookup for that entry also required it to match the connection's BSS
type, so an entry advertising e.g. the IBSS capability bit was left in
place, and the following cfg80211_rehash_bss() then ran into it:
WARN_ON(!cmp)
Changing the type shouldn't really happen, but can be triggered by a
rogue AP/device, so drop the check and remove any entries matching
the comparison.
Assisted-by: LLM
Fixes: 0afd425b1b ("cfg80211: fix duplicated scan entries after channel switch")
Reported-by: syzbot+dc6f4dce0d707900cdea@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=dc6f4dce0d707900cdea
Link: https://patch.msgid.link/20260904165614.1f05dae1c546.Ib52d57b57caa912efee020f9d4a033a5160617ce@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a probe response for an unknown BSS comes in, __cfg80211_bss_update()
looks for an existing entry with the same BSSID and a hidden (zero-length
or NUL-filled) SSID, and if it finds one it groups them, using the beacon
IEs from the existing entry.
But that could find another entry without a beacon, if it was also from a
probe response (with SSID), so there's a group without beacon elements.
If a beacon with a hidden SSID for that BSSID arrives later,
cfg80211_combine_bsses() goes looking for the probe response entries that
belong to it - i.e. entries with the same BSSID and channel that have no
beacon IEs - and finds those two. They are already grouped with each
other, so it hits its
WARN_ON_ONCE(bss->pub.hidden_beacon_bss)
WARN_ON_ONCE(!list_empty(&bss->hidden_list))
which are there because an entry without beacon elements is not supposed
to be part of a group yet.
Only combine entries when a beacon was already received, ones that are
kept separate will be combined when a beacon arrives.
Assisted-by: LLM
Fixes: 4593c4cbe1 ("cfg80211: fix BSS list hidden SSID lookup")
Reported-by: syzbot+1a797e1c81be78a2ace7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1a797e1c81be78a2ace7
Link: https://patch.msgid.link/20260904165614.bcfa64715745.Iad740347c86de56d4ff4f96a95f3c3afc47c42de@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
swsusp_arch_suspend_exit() reinstalls the restored kernel's hyp stub
vectors with an hvc, but never passes the arguments. x0 is not set to
HVC_SET_VECTORS and x1 is not set to the vector address, so the stub
dispatch falls through and returns without writing vbar_el2. EL2 is
left pointing at the trans_pgd copy of the vectors, a page that
swsusp_free() releases right after resume.
Set the arguments up the same way __hyp_set_vectors() does.
Without this fix, Vladimir was able to trigger a hang when resuming from
hibernation with CONFIG_PAGE_POISONING=y and page_poison=on.
Fixes: 788bfdd974 ("arm64: trans_pgd: hibernate: Add trans_pgd_copy_el2_vectors")
Cc: stable@vger.kernel.org
Signed-off-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
When an interface goes down while a scan is running, cfg80211 completes
the scan towards userspace and frees the scan request. However, the
driver can be convinced that it owns the request, since the cancellation
is (intended to be) asynchronous.
The WARN_ON() in the netdev notifier was meant to catch this, but it's
not actually avoidable, so it triggers and we get a UAF in scan_done().
There doesn't seem to be a great way around it, so just track that the
driver is still convinced it owns the request, and then just free it on
completion if it was already cancelled. Also remove the warnings since
they can trigger in the intended architecture.
Assisted-by: LLM
Fixes: 4a58e7c384 ("cfg80211: don't "leak" uncompleted scans")
Reported-by: syzbot+189dcafc06865d38178d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=189dcafc06865d38178d
Link: https://patch.msgid.link/20260904165614.375e543228b1.I03cbb5a54cb02d6bba5034286af1ed73aba134d1@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
dma_issue_pending_all() walks the dma_device_list with
list_for_each_entry_rcu() under rcu_read_lock(). dma_device_release()
unlinks the device with list_del_rcu() and then calls
device->device_release() (which in many drivers, such as plx_dma.c,
directly calls kfree()).
Because there is no grace period between unlinking the device and
freeing it, concurrent RCU readers in dma_issue_pending_all() can
access the device after it has been freed.
The lockless walk originally relied on clients holding a dmaengine
reference to pin the provider module, and therefore the device, for as
long as they might traverse the list. Commit 8ad342a863 ("dmaengine:
Add reference counting to dma_device struct") decoupled the dma_device
lifetime from the module reference, so the device can now be released
while a reader is still walking the list.
Add synchronize_rcu() before the device is freed, so RCU readers are
guaranteed to have finished. Keep it unconditional: providers that do
not implement device_release() free the device themselves once
dma_async_device_unregister() returns. This call will delay for a grace
period with dma_list_mutex held, which is safe and only teardown path is
delayed.
Fixes: 2ba05622b8 ("dmaengine: provide a common 'issue_pending_all' implementation")
Suggested-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260526-dmaengine-kref-fix-v2-0-3df60afac01d@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-4-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When dma_device_put() drops the last reference on chan->device->ref,
dma_device_release() runs and may free the dma_device along with its
channels.
dma_chan_put() then still reads chan->device->owner via
dma_chan_to_owner() for the trailing module_put(). KASAN catches it:
slab-use-after-free in dma_chan_put+0x3e6/0x4c0
Read of size 8 by task insmod/6319
Freed by task 6319:
kfree+0x225/0x470
dma_chan_put+0x395/0x4c0
dmaengine_put+0xf8/0x160
Cache the module owner in dma_chan_put() before the put so the trailing
module_put() does not need chan->device.
Fixes: 8ad342a863 ("dmaengine: Add reference counting to dma_device struct")
Suggested-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
dma_chan_get() takes chan->device->ref only on the slow path:
/* no kref on fast path */
if (chan->client_count) {
__module_get(owner);
chan->client_count++;
return 0;
}
if (!try_module_get(owner))
return -ENODEV;
if (!dma_device_get(chan->device)) { // calls kref_get_unless_zero()
dma_chan_put() drops the ref unconditionally, so every fast-path
get/put pair drops one extra device reference.
The bug fires when two conditions hold together: a non-private
provider has a persistent client holding chan->client_count > 0
and another client cycles dmaengine_get()/dmaengine_put().
When the kref hits zero, the subsequent dma_find_channel() returns
NULL even though the provider module is still loaded.
Fix this by dropping device->ref only on the last put, matching the
single slow-path get.
Fixes: 8ad342a863 ("dmaengine: Add reference counting to dma_device struct")
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-2-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add dma_device_get() helper to match dma_device_put() to make code
symmetric. It wraps open-coded kref_get_unless_zero() and asserts that
dma_list_mutex is held, matching its put counterpart.
No functional change intended.
Suggested-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-1-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
sdio_uart_add_port() allocates the transmit fifo before claiming a
slot in sdio_uart_table[]. When all UART_NR slots are taken, it
returns -EBUSY with the fifo still allocated, but the probe error
path only kfree()s the port, leaking the transmit fifo.
Free the fifo in the failure path of sdio_uart_add_port() itself so
the function retains nothing on error.
Fixes: 8b197a5ce7 ("sdio_uart: Use kfifo instead of the messy circ stuff")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulfh@kernel.org>
dma_alloc_attrs() passes *dma_handle to trace_dma_alloc() without
checking whether the allocation succeeded. No backend writes it on
failure: dma_direct_alloc(), iommu_dma_alloc() and the dma_map_ops
instances assign it only on the path that returns a buffer. Callers
usually pass an uninitialized automatic variable, so a failed allocation
records whatever the stack held, next to the virt_addr=(null) that marks
the record as an error:
dma_alloc: dmatrace dir=BIDIRECTIONAL dma_addr=deadbeefdeadbeef
size=1099511627776 virt_addr=0000000000000000
The device coherent pool path reaches the same call: a non-zero return
from dma_alloc_from_dev_coherent() means the request was handled, not
that it succeeded, so cpu_addr is NULL and dma_handle is untouched once
the pool runs out.
For an allocation event a NULL virt_addr already means the request
failed, so the address field carries nothing. Report 0 for it in the
event class rather than at each call site, which covers dma_alloc_pages()
and dma_alloc_sgt_err() as well.
Fixes: 038eb433dc ("dma-mapping: add tracing for dma-mapping API calls")
Fixes: 68b6dbf1f4 ("dma-mapping: trace more error paths")
Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com>
Link: https://lore.kernel.org/r/20260907120124.603373-1-donggeunyoo.kernel@gmail.com
Reviewed-by: Sean Anderson <sean.anderson@linux.dev>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
The tc358768 declares static bridge timings requiring pixel data to be
sampled on the positive clock edge.
However, the DRM core default propagation simply copies the output-side
bus flags, coming from the next bridge, connector or panel, to the
input side. If the propagated flags are incompatible with the bridge
ones, the data is wrongly sampled, typically resulting in visual
artifacts on the panel.
Implement the atomic_check hook, replacing the mutually exclusive
mode_fixup, and set the bridge state input bus flags to the ones
required by the tc358768. The sync polarity defaulting previously done
in mode_fixup is carried over into atomic_check unchanged.
Fixes: ff1ca6397b ("drm/bridge: Add tc358768 driver")
Cc: stable@vger.kernel.org
Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Reviewed-by: Swamil Jain <s-jain1@ti.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Link: https://patch.msgid.link/20260706132440.1594239-1-leoreis.costa@gmail.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
legitimize_ns() takes a reference on the candidate namespace before
may_list_ns() has decided whether the caller may see it. The
__free(ns_put) cleanup on the denied path can drop the last reference to a
mount namespace while we still hold the rcu read lock, and put_mnt_ns()
may sleep there. This is the same problem commit 2ec2aff3c8 ("ns: make
sure reference are dropped outside of rcu lock") fixed for the put_user()
path. Neither ns_requested() nor may_list_ns() needs a reference, both
only look at the namespace type and at the caller's own namespaces, so do
the checks first and take the reference last.
Splat:
Voluntary context switch within RCU read-side critical section!
WARNING: kernel/rcu/tree_plugin.h:332 at rcu_note_context_switch+0x238/0x2a0, CPU#5: a/3442
CPU: 5 UID: 1000 PID: 3442 Comm: a Not tainted 7.0.0-30-generic #30-Ubuntu PREEMPT(lazy)
RIP: 0010:rcu_note_context_switch+0x238/0x2a0
Call Trace:
<TASK>
__schedule+0xcf/0x650
schedule+0x27/0x90
schedule_preempt_disabled+0x15/0x30
__mutex_lock.constprop.0+0x550/0xaf0
__mutex_lock_slowpath+0x13/0x20
mutex_lock+0x3b/0x50
exp_funnel_lock+0xb2/0x260
synchronize_rcu_expedited+0xe7/0x220
namespace_unlock+0x26a/0x320
put_mnt_ns+0xd3/0x120
mntns_put+0xe/0x20
do_listns+0x13e/0x560
__do_sys_listns+0x126/0x2d0
__x64_sys_listns+0x20/0x30
x64_sys_call+0x2366/0x2390
do_syscall_64+0x105/0x5a0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK>
Fixes: 76b6f5dfb3 ("nstree: add listns()")
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Link: https://patch.msgid.link/ABA32239-733B-438C-B95A-B13ED69FF0F3@doyensec.com
Reviewed-by: Bradley Morgan <brads@mainlining.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
do_close_on_exec() currently happens while holding the exec_update_lock,
which is used in a lot of places that access process state to
synchronize access checks.
I recently added another such use of exec_update_lock, causing a
regression.
do_close_on_exec() can block waiting for a reply from a filesystem.
That means a hung filesystem can block codepaths that use
exec_update_lock; and it also means that a FUSE filesystem which
attempts to inspect the calling process can deadlock.
To avoid such problems, move do_close_on_exec() before the
exec_update_lock is taken, but after the FD table has been copied if
necessary.
I have looked through all the calls between the old and new position of
the do_close_on_exec() call; there seems to be no file descriptor table
access in between.
Reported-by: Benjamin Peterson <benjamin@locrian.net>
Closes: https://lore.kernel.org/r/f5e8166a-88be-46c5-8939-1e5227ffe4c2@app.fastmail.com
Fixes: 6650527444 ("proc: protect ptrace_may_access() with exec_update_lock (part 1)")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Link: https://patch.msgid.link/20260907-cloexec-before-exec-update-lock-v1-1-8018c201a7df@google.com
Tested-by: Benjamin Peterson <benjamin@locrian.net>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Some of users of Polars (a data analytics library) have lost production
data from this bug. They seem to have just the right combination of
huge pages, MADV_FREE and heavy reclaim pressure.
pmd_modify() masks the old value with (_HPAGE_CHG_MASK & ~_PAGE_DIRTY),
silently discarding the hardware dirty bit. The subsequent
pmd_mksaveddirty() call is supposed to transfer _PAGE_DIRTY into
_PAGE_SAVED_DIRTY when write-protecting, but the dirty bit was already
stripped from the value, so there is nothing left to transfer.
Contrast with pte_modify(), which keeps _PAGE_DIRTY_BITS in its mask,
and pud_modify(), which keeps _HPAGE_CHG_MASK untouched: pmd_modify()
is the odd one out. Any pmd_modify() on a writable, dirty PMD loses
the dirty state.
One visible consequence is data loss with MADV_FREE on PMD-mapped THP:
memset(buf, 0x5A, size); // PMD-mapped THP, PMD dirty
madvise(buf, size, MADV_FREE); // PMD cleaned but left writable,
// folio marked lazyfree
memset(buf, 0x5A, size); // hardware sets _PAGE_DIRTY again
mprotect(buf, size, PROT_READ); // pmd_modify() drops the dirty bit
mprotect(buf, size, PROT_READ|PROT_WRITE);
// ... memory pressure ...
Reclaim (e.g. under memcg pressure) then finds the lazyfree folio with
no dirty bit set anywhere and frees it in
__discard_anon_folio_pmd_locked(), even though the data was rewritten
after MADV_FREE; subsequent reads fault in fresh zero pages. NUMA
hinting alone can trigger the same loss, as do_huge_pmd_numa_page()
restores the PMD through pmd_modify() as well.
PMD-mapped file THPs are affected too: mprotect()/NUMA hinting dropping
the dirty bit means rewritten data is never written back.
Fix it by keeping _PAGE_DIRTY in the preserved mask, exactly like
pte_modify() and pud_modify() do. The existing
pmd_mksaveddirty()/pmd_clear_saveddirty() pair then performs the
hardware-dirty <-> saved-dirty transition based on the write bit,
preserving the shadow-stack encoding rules.
Fixes: bb3aadf7d4 ("x86/mm: Start actually marking _PAGE_SAVED_DIRTY")
Closes: https://lore.kernel.org/r/CAJxLxMUGu1-L+O_nAONOwOXnS=cNbNApCWqdthRjd76LThtSPg@mail.gmail.com/
Reported-by: Orson Peters <orsonpeters@gmail.com>
Signed-off-by: Vernon Yang <yanglincheng@kylinos.cn>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260903031608.1194238-1-vernon2gm@gmail.com
A PTE is allocated directly without going through the standard page table
allocation routines (such as pte_alloc_one_kernel()) when the CPA code
splits a large page (__split_large_page()).
This means the page table constructor is never called nor is the page table
marked as a kernel page table.
The former results in the folio associated with the page table not being
marked as a page table (__pagetable_ctor() is never called thus neither is
__folio_set_pgtable()) nor are statistics updated to reflect
it (lruvec_stat_add_folio() is never called).
The latter issue of failing to mark the page table as a kernel page
table (ptdesc_set_kernel() is never called) is far more problematic.
Since commit:
5ba2f0a155 ("mm: introduce deferred freeing for kernel page tables")
kernel page table freeing has been batched and since the
subsequent commit:
e37d5a2d60 ("iommu/sva: invalidate stale IOTLB entries for kernel address space")
IOTLB cache entries for kernel page tables have been invalidated upon
being freed.
Since split page tables are freed without this invalidation, the IOTLB
can contain stale entries for them.
Resolve the issue by using the ordinary PTE allocation API at split time.
This results in these kernel page tables invoking a page table constructor,
and thus requires a page table destructor.
Destructors are not always present, like for early allocated direct map
page tables). Conditionally call pagetable_dtor_free() if the PG_table
folio flag for the ptdesc is set, otherwise we free the page table via
pagetable_free().
Regardless of which path is taken page tables marked as kernel page tables,
which now includes split page tables, take the correct route through
pagetable_free_kernel().
There is a user-visible side effect in that split page tables will appear
in nr_page_table_pages in /proc/vmstat (as do other kernel page tables
allocated after early boot), however this is a positive change.
This issue started being markedly problematic after commit:
5ba2f0a155 ("mm: introduce deferred freeing for kernel page tables")
so choose this as the Fixes target.
[ dhansen: rephrase in imperative mood ]
Fixes: 5ba2f0a155 ("mm: introduce deferred freeing for kernel page tables")
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Vishal Moola <vishal.moola@gmail.com>
Tested-by: Atish Patra <atishp@meta.com>
Tested-by: Nikunj A Dadhania <nikunj@amd.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260813-cpa-fixes-v2-4-39b4ff90f91d@kernel.org
From time to time, the following BUG can be observed
in the x86 alternatives patching code [0]:
> kernel BUG at arch/x86/kernel/alternative.c:2576!
> Oops: invalid opcode: 0000 [#1] SMP NOPTI
> CPU: 0 UID: 0 PID: 355 Comm: (udev-worker) Not tainted 7.1.3-1-default #1 PREEMPT(full) openSUSE Tumbleweed 8c1795b03ec64f997e57a8ad38b1161e3b98da64
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022
> RIP: 0010:__text_poke+0x2aa/0x450
> Call Trace:
> <TASK>
> smp_text_poke_batch_finish+0x2a7/0x320
> __static_call_transform+0xb7/0x220
> arch_static_call_transform+0x5b/0xb0
> __static_call_init+0xe9/0x270
> static_call_module_notify+0x11f/0x150
> notifier_call_chain+0x61/0xe0
> blocking_notifier_call_chain_robust+0x63/0xc0
> load_module+0x1c92/0x20c0
> init_module_from_file+0xd8/0x140
> idempotent_init_module+0x100/0x2f0
> __x64_sys_finit_module+0x71/0xe0
> do_syscall_64+0xe1/0x610
> entry_SYSCALL_64_after_hwframe+0x76/0x7e
which matches the following BUG_ON() in alternative.c:
/*
* If something went wrong, crash and burn since recovery paths are not
* implemented.
*/
BUG_ON(!pages[0] || (cross_page_boundary && !pages[1]));
This can happen if vmalloc_to_page() fails, for any reason. Such can happen
if text poking races with CPA, which can possibly result in the collapsing
of page tables (or breaking of PMD hugepages). It is not a problem for most
users of vmalloc_to_page() (they solely own the vmalloc'd range) but, when
CONFIG_ARCH_HAS_EXECMEM_ROX=y, various modules own a single execmem vmalloc
range, and can call set_memory_*() in parallel on it. This can happen to
race against __text_poke and cause havoc in vmalloc_to_page().
Fix it by excluding against CPA using the init_mm mmap read lock.
[ dhansen: Fix up SoB ordering. The actual code flow here was:
Pedro=>Lorenzo=>Mike=>Me which is reflected in the SoB chain
now. I *believe* Mike simply picked up Lorenzo's update to
Pedro's post from the Link ]
Fixes: 64f6a4e10c ("x86: re-enable EXECMEM_ROX support")
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Reported-by: Steffen Dirkwinkel <lists@steffen.cc>
Signed-off-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Co-developed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jiri Slaby <jirislaby@kernel.org>
Tested-by: Atish Patra <atishp@meta.com>
Tested-by: Nikunj A Dadhania <nikunj@amd.com>
Cc: stable@vger.kernel.org
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1271202 [0]
Link: https://lore.kernel.org/linux-mm/555ea1d43a12c30a8f1eaf10c899b3790d728f33.camel@dirkwinkel.cc/
Link: https://patch.msgid.link/20260813-cpa-fixes-v2-3-39b4ff90f91d@kernel.org
A previous commit protected against races between ptdump and CPA collapse,
however one still exists between attribute changes and collapse as reported
by Denis V. Lunev (linked).
When an attribute change arises, a lockless page table walker obtains a PTE
entry, which is later written to via set_pte_atomic():
...
-> change_page_attr_set_clr()
-> __change_page_attr_set_clr()
-> __change_page_attr()
-> _lookup_address_cpa()
-> lookup_address_in_pgd_attr()
-> [ lockless page table walker ]
-> set_pte_atomic()
There is nothing preventing a concurrent CPA collapse which can free the
PTE that was retrieved here, resulting in a use-after-free.
With the mmap write lock taken on init_mm over CPA collapse, resolve this
race by acquiring an mmap read lock on init_mm over
__change_page_attr_set_clr().
This locks across the whole operation over which the walk and the PTE
entry write occurs, solving the race.
It is safe to do this here, as no spinlocks are held upon entry to
__change_page_attr_set_clr().
However, the lock must not be held over an allocation, as allocation can
trigger reclaim and shrinkers may call into CPA recursively, making
deadlocks possible (init_mm -> ... -> fs_reclaim -> init_mm).
A page table is allocated when a huge page needs to be split:
-> change_page_attr_set_clr()
-> __change_page_attr_set_clr()
-> __change_page_attr()
-> split_large_page()
[ pagetable_alloc() ]
-> __split_large_page()
Avoid deadlocks by dropping the mmap lock across pagetable_alloc() in
split_large_page() and track whether this is needed by adding a new
'init_mm_read_locked' flag to struct cpa_data.
This is safe as __split_large_page() (called with locks re-established)
revalidates that the page table entry is the same as it was prior to the
locks being dropped and __change_page_attr() repeats the entire page table
walk whenever a split occurs, so concurrent split and collapse are
accounted for.
Concurrent ptdump is also safe as the lock is only dropped over page table
allocation during which time the page table has not yet been modified.
The CPA_COLLAPSE flag is only set by set_memory_rox(), which exclusively
operates upon vmalloc ranges, and on x86 only within the module mapping
space.
This is important, because some callers directly invoke
__change_page_attr_set_clr(), bypassing this lock. However, none of these
operate within the module mapping space.
* cpa_process_alias() - a recursive helper called by
__change_page_attr_set_clr().
* __set_memory_enc_pgtable() - operates on the direct mapping and (via
__vmbus_establish_gpadl()) the vmalloc mapping space.
* __set_pages_[n]p() - called by set_direct_map_[invalid, default,
valid]_noflush(), __kernel_map_pages() - operates on the direct map.
* kernel_[un]map_pages_in_pgd() - operates on EFI ranges.
This work is based upon Denis V. Lunev's excellent analysis of the bug
with gratitude.
[ dhansen: move to imperative voice in changelog ]
Fixes: 41d88484c7 ("x86/mm/pat: restore large ROX pages after fragmentation")
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Atish Patra <atishp@meta.com>
Tested-by: Nikunj A Dadhania <nikunj@amd.com>
Link: https://lore.kernel.org/all/20260626163213.2284080-1-den@openvz.org/
Cc:stable@vger.kernel.org
Link: https://patch.msgid.link/20260813-cpa-fixes-v2-2-39b4ff90f91d@kernel.org
x86 implements page attribute modification using its Change Page
Attributes (CPA) mechanism.
This tracks properties of ranges such as cache mode through x86 page
attributes, and as part of that logic manipulates kernel page tables.
Since commit:
41d88484c7 ("x86/mm/pat: restore large ROX pages after fragmentation")
ranges of kernel page table entries can be collapsed into
huge page table entries as part of this logic.
As part of this collapse, it frees the page tables which the collapsed
entries previously pointed to, and it does so without any relevant locks
being held to preclude concurrent kernel page table walkers.
The only way this code can be reached is if CPA_COLLAPSE is specified, and
this is only set in set_memory_rox() via:
set_memory_rox()
-> change_page_attr_set_clr()
-> cpa_flush()
-> cpa_collapse_large_pages()
Notable users of this are execmem and BPF when manipulating executable
mappings.
However, this is problematic for ptdump as it walks ranges it does not own
and thus runs the risk of a use-after-free on page tables freed underneath
it.
In addition, concurrent CPA collapse operations are possible which can also
cause races.
Resolve the issue by acquiring the mmap write lock on init_mm across the
whole operation.
It is safe to acquire a sleeping lock as all the callers invoke
set_memory_rox() from process context and in any case,
change_page_attr_set_clr() calls vm_unmap_alias() which ultimately takes a
mutex, disallowing atomic context here.
Fixes: 41d88484c7 ("x86/mm/pat: restore large ROX pages after fragmentation")
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Will Deacon <will@kernel.org>
Reviewed-by: David Carlier <devnexen@gmail.com>
Tested-by: Atish Patra <atishp@meta.com>
Tested-by: Nikunj A Dadhania <nikunj@amd.com>
Cc:stable@vger.kernel.org
Link: https://patch.msgid.link/20260813-cpa-fixes-v2-1-39b4ff90f91d@kernel.org
swiotlb_bounce() reads the page frame number from the slot's recorded
orig_addr, then advances orig_addr by tlb_offset to reach the address
the caller asked about. The highmem branch mixes the two: the offset
within the page comes from the adjusted address, the page from the value
before it.
Once the adjustment crosses a page boundary the pair no longer describes
one location, and the whole copy lands one page below the intended one
for a positive tlb_offset, one above for a negative one. DMA_FROM_DEVICE
writes the device data over the wrong page and leaves the intended one
stale, DMA_TO_DEVICE feeds the device from a page the mapping may not
cover. Partial syncs through dma_sync_single_range_for_*() are what make
tlb_offset non-zero.
The branch test is picked the same way, so a slot recorded in lowmem can
be adjusted into highmem and the lowmem path then hands a highmem
address to phys_to_virt().
Take both from orig_addr once it is final and keep pfn in the branch
that uses it. PhysHighMem() asks the question straight from the address,
as dma-debug already does.
Fixes: 5f89468e2f ("swiotlb: manipulate orig_addr when tlb_addr has offset")
Cc: stable@vger.kernel.org
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20260905084210.148255-1-donggeunyoo.kernel@gmail.com
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
rmem_dma_device_init() drops the return value of
dma_assign_coherent_memory() and always reports success. That call fails
with -EBUSY when the device already has a coherent pool, and the file
allows only "*one* such region of memory" per device.
of_reserved_mem_device_init_by_idx() reads the zero as success. It logs
"assigned reserved memory node" for a region that was not assigned and
records the pairing, so of_reserved_mem_device_release() later runs
rmem_dma_device_release() for it. That clears dev->dma_mem without
looking at which region it was called for, dropping the pool the device
did get and leaving it on ordinary memory.
dma_declare_coherent_memory() checks the same call and releases the
memory on failure, and rmem_swiotlb_device_init() propagates its own
errors. Return the error here as well, so a device tree that assigns two
pools to one device fails the probe instead of half working.
Fixes: 7bfa5ab6fa ("drivers: dma-coherent: add initialization from device tree")
Signed-off-by: Donggeun Yoo <donggeunyoo.kernel@gmail.com>
Link: https://lore.kernel.org/r/20260905074727.108029-1-donggeunyoo.kernel@gmail.com
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
To simplify independent development in the KVM and MM subsystems, now
export to KVM the lru_cache_drain_for_folio() which MM added in 7.3-rc1.
Link: https://lore.kernel.org/lkml/bd6c9c74-e374-a9d3-ba1f-8b6f430894fc@google.com/T/#u
Link: https://lore.kernel.org/02876cea-5727-2ca4-bead-73659ea6fec4@google.com
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Suggested-by: David Hildenbrand <david@kernel.org>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
With cgroup.memory=nokmem, shrinker_memcg_alloc() bails out early and
never allocates an id, so shrinker->id keeps the 0 it got from the
kzalloc() in shrinker_alloc(). __list_lru_init() then copies that 0 into
lru->shrinker_id, where it looks like a valid bit index.
Nothing calls expand_shrinker_info() on nokmem either, so shrinker_nr_max
stays 0 and every memcg ends up with an empty map (map_nr_max == 0).
deferred_split_folio() hands a real memcg to __list_lru_add() regardless
of whether the lru is memcg aware, so the first THP queued in a cgroup
does set_shrinker_bit(memcg, nid, 0) and trips the bounds check:
WARNING: mm/shrinker.c:212 at set_shrinker_bit+0x7d/0x90, CPU#126
Call Trace:
<TASK>
deferred_split_folio+0x18c/0x220
map_anon_folio_pmd_nopf+0xdd/0x130
map_anon_folio_pmd_pf+0x14/0xb0
do_huge_pmd_anonymous_page+0x1a1/0x620
__handle_mm_fault+0xea9/0x10d0
handle_mm_fault+0xe5/0x320
do_user_addr_fault+0x1cc/0x870
exc_page_fault+0x81/0x1b0
asm_exc_page_fault+0x27/0x30
</TASK>
Harmless, the WARN_ON_ONCE() is what keeps the out of bounds unit[] read
from happening, but the id should not look valid in the first place.
Clear it before returning.
Two other spots could paper over this: drop the id in __list_lru_init()
when nokmem turns memcg_aware off, or make deferred_split_folio() pass
NULL like list_lru_add_obj() does. Both leave shrinker->id lying around
for the next caller, so fix it where the id is handed out.
Link: https://lore.kernel.org/20260902073800.305481-1-jiayuan.chen@linux.dev
Fixes: fafaeceb89 ("mm: switch deferred split shrinker to list_lru")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Usama Arif <usama.arif@linux.dev>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
