The response buffer for the CREATE request handled by smb311_posix_mkdir()
is leaked on the error path (goto err_free_rsp_buf) because the structure
pointer *rsp passed to free_rsp_buf() is not assigned until *after* the
error condition is checked.
As *rsp is initialised to NULL, free_rsp_buf() becomes a no-op and the leak
is instead reported by __kmem_cache_shutdown() upon subsequent rmmod of
cifs.ko if (and only if) the error path has been hit.
Pass rsp_iov.iov_base to free_rsp_buf() instead, similar to the code in
other functions in smb2pdu.c for which *rsp is assigned late.
Cc: stable@vger.kernel.org Signed-off-by: Jethro Donaldson <devel@jro.nz> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The REPORT ZONES buffer size is currently limited by the HBA's maximum
segment count to ensure the buffer can be mapped. However, the block
layer further limits the number of iovec entries to 1024 when allocating
a bio.
To avoid allocation of buffers too large to be mapped, further restrict
the maximum buffer size to BIO_MAX_INLINE_VECS.
Replace the UIO_MAXIOV symbolic name with the more contextually
appropriate BIO_MAX_INLINE_VECS.
Fixes: b091ac616846 ("sd_zbc: Fix report zones buffer allocation") Cc: stable@vger.kernel.org Signed-off-by: Steve Siwinski <ssiwinski@atto.com> Link: https://lore.kernel.org/r/20250508200122.243129-1-ssiwinski@atto.com Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
phy-rcar-gen3-usb2 driver exports 4 PHYs. The timing registers are common
to all PHYs. There is no need to set them every time a PHY is initialized.
Set timing register only when the 1st PHY is initialized.
It has been observed on the Renesas RZ/G3S SoC that unbinding and binding
the PHY driver leads to role autodetection failures. This issue occurs when
PHY 3 is the first initialized PHY. PHY 3 does not have an interrupt
associated with the USB2_INT_ENABLE register (as
rcar_gen3_int_enable[3] = 0). As a result, rcar_gen3_init_otg() is called
to initialize OTG without enabling PHY interrupts.
To resolve this, add rcar_gen3_is_any_otg_rphy_initialized() and call it in
role_store(), role_show(), and rcar_gen3_init_otg(). At the same time,
rcar_gen3_init_otg() is only called when initialization for a PHY with
interrupt bits is in progress. As a result, the
struct rcar_gen3_phy::otg_initialized is no longer needed.
If device_add() fails, do not use device_unregister() for error
handling. device_unregister() consists two functions: device_del() and
put_device(). device_unregister() should only be called after
device_add() succeeded because device_del() undoes what device_add()
does if successful. Change device_unregister() to put_device() call
before returning from the function.
As comment of device_add() says, 'if device_add() succeeds, you should
call device_del() when you want to get rid of it. If device_add() has
not succeeded, use only put_device() to drop the reference count'.
Found by code review.
Cc: stable@vger.kernel.org Fixes: 53d2a715c240 ("phy: Add Tegra XUSB pad controller support") Signed-off-by: Ma Ke <make24@iscas.ac.cn> Acked-by: Thierry Reding <treding@nvidia.com> Link: https://lore.kernel.org/r/20250303072739.3874987-1-make24@iscas.ac.cn Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current implementation uses bias_pad_enable as a reference count to
manage the shared bias pad for all UTMI PHYs. However, during system
suspension with connected USB devices, multiple power-down requests for
the UTMI pad result in a mismatch in the reference count, which in turn
produces warnings such as:
The root cause was traced back to the dynamic power-down changes
introduced in commit a30951d31b25 ("xhci: tegra: USB2 pad power controls"),
where the UTMI pad was being powered down without verifying its current
state. This unbalanced behavior led to discrepancies in the reference
count.
To rectify this issue, this patch replaces the single reference counter
with a bitmask, renamed to utmi_pad_enabled. Each bit in the mask
corresponds to one of the four USB2 PHYs, allowing us to track each pad's
enablement status individually.
With this change:
- The bias pad is powered on only when the mask is clear.
- Each UTMI pad is powered on or down based on its corresponding bit
in the mask, preventing redundant operations.
- The overall power state of the shared bias pad is maintained
correctly during suspend/resume cycles.
The mutex used to prevent race conditions during UTMI pad enable/disable
operations has been moved from the tegra186_utmi_bias_pad_power_on/off
functions to the parent functions tegra186_utmi_pad_power_on/down. This
change ensures that there are no race conditions when updating the bitmask.
Cc: stable@vger.kernel.org Fixes: a30951d31b25 ("xhci: tegra: USB2 pad power controls") Signed-off-by: Wayne Chang <waynec@nvidia.com> Reviewed-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Link: https://lore.kernel.org/r/20250408030905.990474-1-waynec@nvidia.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using the stacktrace trigger command to trace syscalls, the
preemption count was consistently reported as 1 when the system call
event itself had 0 (".").
The root cause is that the trace framework disables preemption in __DO_TRACE before
invoking the trigger callback.
Use the tracing_gen_ctx_dec() that will accommodate for the increase of
the preemption count in __DO_TRACE when calling the callback. The result
is the accurate reporting of:
With the netvsc driver changed to use vmbus_sendpacket_mpb_desc()
instead of vmbus_sendpacket_pagebuffer(), the latter has no remaining
callers. Remove it.
Cc: <stable@vger.kernel.org> # 6.1.x Signed-off-by: Michael Kelley <mhklinux@outlook.com> Link: https://patch.msgid.link/20250513000604.1396-6-mhklinux@outlook.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vmbus_sendpacket_mpb_desc() is currently used only by the storvsc driver
and is hardcoded to create a single GPA range. To allow it to also be
used by the netvsc driver to create multiple GPA ranges, no longer
hardcode as having a single GPA range. Allow the calling driver to
specify the rangecount in the supplied descriptor.
Update the storvsc driver to reflect this new approach.
Cc: <stable@vger.kernel.org> # 6.1.x Signed-off-by: Michael Kelley <mhklinux@outlook.com> Link: https://patch.msgid.link/20250513000604.1396-2-mhklinux@outlook.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
init_page_array() now always creates a single page buffer array entry
for the rndis message, even if the rndis message crosses a page
boundary. As such, the number of page buffer array entries used for
the rndis message must no longer be tracked -- it is always just 1.
Remove the rmsg_pgcnt field and use "1" where the value is needed.
Cc: <stable@vger.kernel.org> # 6.1.x Signed-off-by: Michael Kelley <mhklinux@outlook.com> Link: https://patch.msgid.link/20250513000604.1396-5-mhklinux@outlook.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting with commit dca5161f9bd0 ("hv_netvsc: Check status in
SEND_RNDIS_PKT completion message") in the 6.3 kernel, the Linux
driver for Hyper-V synthetic networking (netvsc) occasionally reports
"nvsp_rndis_pkt_complete error status: 2".[1] This error indicates
that Hyper-V has rejected a network packet transmit request from the
guest, and the outgoing network packet is dropped. Higher level
network protocols presumably recover and resend the packet so there is
no functional error, but performance is slightly impacted. Commit dca5161f9bd0 is not the cause of the error -- it only added reporting
of an error that was already happening without any notice. The error
has presumably been present since the netvsc driver was originally
introduced into Linux.
The root cause of the problem is that the netvsc driver in Linux may
send an incorrectly formatted VMBus message to Hyper-V when
transmitting the network packet. The incorrect formatting occurs when
the rndis header of the VMBus message crosses a page boundary due to
how the Linux skb head memory is aligned. In such a case, two PFNs are
required to describe the location of the rndis header, even though
they are contiguous in guest physical address (GPA) space. Hyper-V
requires that two rndis header PFNs be in a single "GPA range" data
struture, but current netvsc code puts each PFN in its own GPA range,
which Hyper-V rejects as an error.
The incorrect formatting occurs only for larger packets that netvsc
must transmit via a VMBus "GPA Direct" message. There's no problem
when netvsc transmits a smaller packet by copying it into a pre-
allocated send buffer slot because the pre-allocated slots don't have
page crossing issues.
After commit 14ad6ed30a10 ("net: allow small head cache usage with
large MAX_SKB_FRAGS values") in the 6.14-rc4 kernel, the error occurs
much more frequently in VMs with 16 or more vCPUs. It may occur every
few seconds, or even more frequently, in an ssh session that outputs a
lot of text. Commit 14ad6ed30a10 subtly changes how skb head memory is
allocated, making it much more likely that the rndis header will cross
a page boundary when the vCPU count is 16 or more. The changes in
commit 14ad6ed30a10 are perfectly valid -- they just had the side
effect of making the netvsc bug more prominent.
Current code in init_page_array() creates a separate page buffer array
entry for each PFN required to identify the data to be transmitted.
Contiguous PFNs get separate entries in the page buffer array, and any
information about contiguity is lost.
Fix the core issue by having init_page_array() construct the page
buffer array to represent contiguous ranges rather than individual
pages. When these ranges are subsequently passed to
netvsc_build_mpb_array(), it can build GPA ranges that contain
multiple PFNs, as required to avoid the error "nvsp_rndis_pkt_complete
error status: 2". If instead the network packet is sent by copying
into a pre-allocated send buffer slot, the copy proceeds using the
contiguous ranges rather than individual pages, but the result of the
copying is the same. Also fix rndis_filter_send_request() to construct
a contiguous range, since it has its own page buffer array.
This change has a side benefit in CoCo VMs in that netvsc_dma_map()
calls dma_map_single() on each contiguous range instead of on each
page. This results in fewer calls to dma_map_single() but on larger
chunks of memory, which should reduce contention on the swiotlb.
Since the page buffer array now contains one entry for each contiguous
range instead of for each individual page, the number of entries in
the array can be reduced, saving 208 bytes of stack space in
netvsc_xmit() when MAX_SKG_FRAGS has the default value of 17.
netvsc currently uses vmbus_sendpacket_pagebuffer() to send VMBus
messages. This function creates a series of GPA ranges, each of which
contains a single PFN. However, if the rndis header in the VMBus
message crosses a page boundary, the netvsc protocol with the host
requires that both PFNs for the rndis header must be in a single "GPA
range" data structure, which isn't possible with
vmbus_sendpacket_pagebuffer(). As the first step in fixing this, add a
new function netvsc_build_mpb_array() to build a VMBus message with
multiple GPA ranges, each of which may contain multiple PFNs. Use
vmbus_sendpacket_mpb_desc() to send this VMBus message to the host.
There's no functional change since higher levels of netvsc don't
maintain or propagate knowledge of contiguous PFNs. Based on its
input, netvsc_build_mpb_array() still produces a separate GPA range
for each PFN and the behavior is the same as with
vmbus_sendpacket_pagebuffer(). But the groundwork is laid for a
subsequent patch to provide the necessary grouping.
Cc: <stable@vger.kernel.org> # 6.1.x Signed-off-by: Michael Kelley <mhklinux@outlook.com> Link: https://patch.msgid.link/20250513000604.1396-3-mhklinux@outlook.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
smp_store_mb() inserts memory barrier after storing operation.
It is different with what the comment is originally aiming so Null
pointer dereference can be happened if memory update is reordered.
Signed-off-by: Hyejeong Choi <hjeong.choi@samsung.com> Fixes: a590d0fdbaa5 ("dma-buf: Update reservation shared_count after adding the new fence") CC: stable@vger.kernel.org Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://lore.kernel.org/r/20250513020638.GA2329653@au1-maretx-p37.eng.sarc.samsung.com Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Microdia JP001 does not support reading the sample rate which leads to
many lines of "cannot get freq at ep 0x84".
This patch adds the USB ID to quirks.c and avoids those error messages.
usb 7-4: New USB device found, idVendor=0c45, idProduct=636b, bcdDevice= 1.00
usb 7-4: New USB device strings: Mfr=2, Product=1, SerialNumber=3
usb 7-4: Product: JP001
usb 7-4: Manufacturer: JP001
usb 7-4: SerialNumber: JP001
usb 7-4: 3:1: cannot get freq at ep 0x84
A user reported on the Arch Linux Forums that their device is emitting
the following message in the kernel journal, which is fixed by adding
the quirk as submitted in this patch:
> kernel: usb 1-2: current rate 8436480 is different from the runtime rate 48000
There also is an entry for this product line added long time ago.
Their specific device has the following ID:
$ lsusb | grep Audio
Bus 001 Device 002: ID 1101:0003 EasyPass Industrial Co., Ltd Audioengine D1
The function snd_es1968_capture_open() calls the function
snd_pcm_hw_constraint_pow2(), but does not check its return
value. A proper implementation can be found in snd_cx25821_pcm_open().
Add error handling for snd_pcm_hw_constraint_pow2() and propagate its
error code.
The original PPTT code had a bug where the processor subtable length
was not correctly validated when encountering a truncated
acpi_pptt_processor node.
Commit 7ab4f0e37a0f4 ("ACPI PPTT: Fix coding mistakes in a couple of
sizeof() calls") attempted to fix this by validating the size is as
large as the acpi_pptt_processor node structure. This introduced a
regression where the last processor node in the PPTT table is ignored
if it doesn't contain any private resources. That results errors like:
ACPI PPTT: PPTT table found, but unable to locate core XX (XX)
ACPI: SPE must be homogeneous
Furthermore, it fails in a common case where the node length isn't
equal to the acpi_pptt_processor structure size, leaving the original
bug in a modified form.
Correct the regression by adjusting the loop termination conditions as
suggested by the bug reporters. An additional check performed after
the subtable node type is detected, validates the acpi_pptt_processor
node is fully contained in the PPTT table. Repeating the check in
acpi_pptt_leaf_node() is largely redundant as the node is already
known to be fully contained in the table.
The case where a final truncated node's parent property is accepted,
but the node itself is rejected should not be considered a bug.
Fixes: 7ab4f0e37a0f4 ("ACPI PPTT: Fix coding mistakes in a couple of sizeof() calls") Reported-by: Maximilian Heyne <mheyne@amazon.de> Closes: https://lore.kernel.org/linux-acpi/20250506-draco-taped-15f475cd@mheyne-amazon/ Reported-by: Yicong Yang <yangyicong@hisilicon.com> Closes: https://lore.kernel.org/linux-acpi/20250507035124.28071-1-yangyicong@huawei.com/ Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Tested-by: Yicong Yang <yangyicong@hisilicon.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Maximilian Heyne <mheyne@amazon.de> Cc: All applicable <stable@vger.kernel.org> # 7ab4f0e37a0f4: ACPI PPTT: Fix coding mistakes ... Link: https://patch.msgid.link/20250508023025.1301030-1-jeremy.linton@arm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's expected that we'll encounter temporary exceptions
during aux transactions. Adjust logging from drm_info to
drm_dbg_dp to prevent flooding with unnecessary log messages.
Fixes: 3637e457eb00 ("drm/amd/display: Fix wrong handling for AUX_DEFER case") Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Wayne Lin <Wayne.Lin@amd.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Link: https://lore.kernel.org/r/20250513032026.838036-1-Wayne.Lin@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 9a9c3e1fe5256da14a0a307dff0478f90c55fc8c) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[Why]
Now forcing aux->transfer to return 0 when incomplete AUX write is
inappropriate. It should return bytes have been transferred.
[How]
aux->transfer is asked not to change original msg except reply field of
drm_dp_aux_msg structure. Copy the msg->buffer when it's write request,
and overwrite the first byte when sink reply 1 byte indicating partially
written byte number. Then we can return the correct value without
changing the original msg.
Fixes: 3637e457eb00 ("drm/amd/display: Fix wrong handling for AUX_DEFER case") Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Ray Wu <ray.wu@amd.com> Signed-off-by: Wayne Lin <Wayne.Lin@amd.com> Signed-off-by: Ray Wu <ray.wu@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 7ac37f0dcd2e0b729fa7b5513908dc8ab802b540) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch_uprobe_skip_sstep() returns true if instruction was emulated, that
is to say, there is no need to single step for the emulated instructions.
regs->csr_era will point to the destination address directly after the
exception, so the resume_era related code is redundant, just remove them.
When executing the "perf probe" and "perf stat" test cases about some
cryptographic algorithm, the output shows that "Trace/breakpoint trap".
This is because it uses the software singlestep breakpoint for uprobes
on LoongArch, and no need to use the hardware singlestep. So just remove
the related function call to user_{en,dis}able_single_step() for uprobes
on LoongArch.
How to reproduce:
Please make sure CONFIG_UPROBE_EVENTS is set and openssl supports sm2
algorithm, then execute the following command.
cd tools/perf && make
./perf probe -x /usr/lib64/libcrypto.so BN_mod_mul_montgomery
./perf stat -e probe_libcrypto:BN_mod_mul_montgomery openssl speed sm2
Fix MAX_REG_OFFSET calculation, make it point to the last register
in 'struct pt_regs' and not to the marker itself, which could allow
regs_get_register() to return an invalid offset.
Save and restore CSR.CNTC for hibernation which is similar to suspend.
For host this is unnecessary because sched clock is ensured continuous,
but for kvm guest sched clock isn't enough because rdtime.d should also
be continuous.
When CONFIG_PREEMPT_COUNT is not configured (i.e. CONFIG_PREEMPT_NONE/
CONFIG_PREEMPT_VOLUNTARY), preempt_disable() / preempt_enable() merely
acts as a barrier(). However, in these cases cond_resched() can still
trigger a context switch and modify the CSR.EUEN, resulting in do_fpu()
exception being activated within the kernel-fpu critical sections, as
demonstrated in the following path:
This patch is similar to commit d02198550423a0b (x86/fpu: Improve crypto
performance by making kernel-mode FPU reliably usable in softirqs). It
uses local_bh_disable() instead of preempt_disable() for non-RT kernels
so it can avoid the cond_resched() issue, and also extend the kernel-fpu
application scenarios to the softirq context.
UDF maintains total length of all extents in i_lenExtents. Generally we
keep extent lengths (and thus i_lenExtents) block aligned because it
makes the file appending logic simpler. However the standard mandates
that the inode size must match the length of all extents and thus we
trim the last extent when closing the file. To catch possible bugs we
also verify that i_lenExtents matches i_size when evicting inode from
memory. Commit b405c1e58b73 ("udf: refactor udf_next_aext() to handle
error") however broke the code updating i_lenExtents and thus
udf_evict_inode() ended up spewing lots of errors about incorrectly
sized extents although the extents were actually sized properly. Fix the
updating of i_lenExtents to silence the errors.
Fixes: b405c1e58b73 ("udf: refactor udf_next_aext() to handle error") CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* The analysis is flawed and it's unclear what problem is being
fixed. There is no difference between wait_event_freezable_timeout()
and wait_event_timeout() with respect to device interrupts. And of
course "the interrupt notifying the finish of an operation happens
during wait_event_freezable_timeout()" -- that's how it's supposed
to work.
* The link at the "Closes:" tag appears to be an unrelated
use-after-free in idxd.
* It introduces a regression: dmatest threads are meant to be
freezable and this change breaks that.
See discussion here:
https://lore.kernel.org/dmaengine/878qpa13fe.fsf@AUSNATLYNCH.amd.com/
If there are still layout segments in the layout plh_return_lsegs list
after a layout return, we should be resetting the state to ensure they
eventually get returned as well.
Fixes: 68f744797edd ("pNFS: Do not free layout segments that are marked for return") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
This driver is susceptible to a form of the bug explained in commit c26a2c2ddc01 ("gianfar: Fix TX timestamping with a stacked DSA driver")
and in Documentation/networking/timestamping.rst section "Other caveats
for MAC drivers", specifically it timestamps any skb which has
SKBTX_HW_TSTAMP, and does not consider if timestamping has been enabled
in adapter->hwtstamp_config.tx_type.
Evaluate the proper TX timestamping condition only once on the TX
path (in tsnep_xmit_frame_ring()) and store the result in an additional
TX entry flag. Evaluate the new TX entry flag in the TX confirmation path
(in tsnep_tx_poll()).
This way SKBTX_IN_PROGRESS is set by the driver as required, but never
evaluated. SKBTX_IN_PROGRESS shall not be evaluated as it can be set
by a stacked DSA driver and evaluating it would lead to unwanted
timestamps.
Fixes: 403f69bbdbad ("tsnep: Add TSN endpoint Ethernet MAC driver") Suggested-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20250514195657.25874-1-gerhard@engleder-embedded.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The tsnep network controller is able to extend the descriptor directly
with data to be transmitted. In this case no TX data DMA address is
necessary. Instead of the TX data DMA address the TX data buffer is
placed at the end of the descriptor.
The descriptor is read with a 64 bytes DMA read by the tsnep network
controller. If the sum of descriptor data and TX data is less than or
equal to 64 bytes, then no additional DMA read is necessary to read the
TX data. Therefore, it makes sense to inline small fragments up to this
limit within the descriptor ring.
Inlined fragments need to be copied to the descriptor ring. On the other
hand DMA mapping is not necessary. At most 40 bytes are copied, so
copying should be faster than DMA mapping.
For A53 1.2 GHz copying takes <100ns and DMA mapping takes >200ns. So
inlining small fragments should result in lower CPU load. Performance
improvement is small. Thus, comparision of CPU load with and without
inlining of small fragments did not show any significant difference.
With this optimization less DMA reads will be done, which decreases the
load of the interconnect.
Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: b3ca9eef6646 ("tsnep: fix timestamping with a stacked DSA driver") Signed-off-by: Sasha Levin <sashal@kernel.org>
We cannot set frag_list to NULL pointer when alloc_page failed.
It will be used in tls_strp_check_queue_ok when the next time
tls_strp_read_sock is called.
This is because we don't reset full_len in tls_strp_flush_anchor_copy()
so the recv path will try to continue handling the partial record
on the next call but we dettached the rcvq from the frag list.
Alternative fix would be to reset full_len.
Unable to handle kernel NULL pointer dereference
at virtual address 0000000000000028
Call trace:
tls_strp_check_rcv+0x128/0x27c
tls_strp_data_ready+0x34/0x44
tls_data_ready+0x3c/0x1f0
tcp_data_ready+0x9c/0xe4
tcp_data_queue+0xf6c/0x12d0
tcp_rcv_established+0x52c/0x798
Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser") Signed-off-by: Pengtao He <hept.hept.hept@gmail.com> Link: https://patch.msgid.link/20250514132013.17274-1-hept.hept.hept@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The driver only offloads neighbors that are constructed on top of net
devices registered by it or their uppers (which are all Ethernet). The
device supports GRE encapsulation and decapsulation of forwarded
traffic, but the driver will not offload dummy neighbors constructed on
top of GRE net devices as they are not uppers of its net devices:
# ip link add name gre1 up type gre tos inherit local 192.0.2.1 remote 198.51.100.1
# ip neigh add 0.0.0.0 lladdr 0.0.0.0 nud noarp dev gre1
$ ip neigh show dev gre1 nud noarp
0.0.0.0 lladdr 0.0.0.0 NOARP
(Note that the neighbor is not marked with 'offload')
When the driver is reloaded and the existing configuration is replayed,
the driver does not perform the same check regarding existing neighbors
and offloads the previously added one:
# devlink dev reload pci/0000:01:00.0
$ ip neigh show dev gre1 nud noarp
0.0.0.0 lladdr 0.0.0.0 offload NOARP
If the neighbor is later deleted, the driver will ignore the
notification (given the GRE net device is not its upper) and will
therefore keep referencing freed memory, resulting in a use-after-free
[1] when the net device is deleted:
# ip neigh del 0.0.0.0 lladdr 0.0.0.0 dev gre1
# ip link del dev gre1
Fix by skipping neighbor replay if the net device for which the replay
is performed is not our upper.
Make sure that n_channels is set after allocating the
struct cfg80211_registered_device::int_scan_req member. Seen with
syzkaller:
UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:1208:5
index 0 is out of range for type 'struct ieee80211_channel *[] __counted_by(n_channels)' (aka 'struct ieee80211_channel *[]')
This was missed in the initial conversions because I failed to locate
the allocation likely due to the "sizeof(void *)" not matching the
"channels" array type.
Reported-by: syzbot+4bcdddd48bb6f0be0da1@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/680fd171.050a0220.2b69d1.045e.GAE@google.com/ Fixes: e3eac9f32ec0 ("wifi: cfg80211: Annotate struct cfg80211_scan_request with __counted_by") Signed-off-by: Kees Cook <kees@kernel.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://patch.msgid.link/20250509184641.work.542-kees@kernel.org Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Since MTK_ESW_BIT is a bit number rather than a bitmap, it causes
MTK_HAS_CAPS to produce incorrect results. This leads to the ETH
driver not declaring MAC capabilities correctly for the MT7988 ESW.
Fixes: 445eb6448ed3 ("net: ethernet: mtk_eth_soc: add basic support for MT7988 SoC") Signed-off-by: Bo-Cun Chen <bc-bocun.chen@mediatek.com> Signed-off-by: Daniel Golle <daniel@makrotopia.org> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Link: https://patch.msgid.link/b8b37f409d1280fad9c4d32521e6207f63cd3213.1747110258.git.daniel@makrotopia.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
MASCEC hardware block has a field called maximum transmit size for
TX secy. Max packet size going out of MCS block has be programmed
taking into account full packet size which has L2 header,SecTag
and ICV. MACSEC offload driver is configuring max transmit size as
macsec interface MTU which is incorrect. Say with 1500 MTU of real
device, macsec interface created on top of real device will have MTU of
1468(1500 - (SecTag + ICV)). This is causing packets from macsec
interface of size greater than or equal to 1468 are not getting
transmitted out because driver programmed max transmit size as 1468
instead of 1514(1500 + ETH_HDR_LEN).
max20086_parse_regulators_dt() calls of_regulator_match() using an
array of struct of_regulator_match allocated on the stack for the
matches argument.
of_regulator_match() calls devm_of_regulator_put_matches(), which calls
devres_alloc() to allocate a struct devm_of_regulator_matches which will
be de-allocated using devm_of_regulator_put_matches().
struct devm_of_regulator_matches is populated with the stack allocated
matches array.
If the device fails to probe, devm_of_regulator_put_matches() will be
called and will try to call of_node_put() on that stack pointer,
generating the following dmesg entries:
max20086 6-0028: Failed to read DEVICE_ID reg: -121
kobject: '\xc0$\xa5\x03' (000000002cebcb7a): is not initialized, yet
kobject_put() is being called.
Followed by a stack trace matching the call flow described above.
Switch to allocating the matches array using devm_kcalloc() to
avoid accessing the stack pointer long after it's out of scope.
This also has the advantage of allowing multiple max20086 to probe
without overriding the data stored inside the global of_regulator_match.
Fixes: bfff546aae50 ("regulator: Add MAX20086-MAX20089 driver") Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Link: https://patch.msgid.link/20250508064947.2567255-1-demonsingur@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
In one of the error paths in qlcnic_sriov_channel_cfg_cmd(), the memory
allocated in qlcnic_sriov_alloc_bc_mbx_args() for mailbox arguments is
not freed. Fix that by jumping to the error path that frees them, by
calling qlcnic_free_mbx_args(). This was found using static analysis.
Fixes: f197a7aa6288 ("qlcnic: VF-PF communication channel implementation") Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250512044829.36400-1-abdun.nihaal@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
MACsec offload is not supported in switchdev mode for uplink
representors. When switching to the uplink representor profile, the
MACsec offload feature must be cleared from the netdevice's features.
If left enabled, attempts to add offloads result in a null pointer
dereference, as the uplink representor does not support MACsec offload
even though the feature bit remains set.
Clear NETIF_F_HW_MACSEC in mlx5e_fix_uplink_rep_features().
The only reason nvme_pci_npages_prp() could be used as a compile-time
known result in BUILD_BUG_ON() is because the compiler was always choosing
to inline the function. Under special circumstances (sanitizer coverage
functions disabled for __init functions on ARCH=um), the compiler decided
to stop inlining it:
drivers/nvme/host/pci.c: In function 'nvme_init':
include/linux/compiler_types.h:557:45: error: call to '__compiletime_assert_678' declared with attribute error: BUILD_BUG_ON failed: nvme_pci_npages_prp() > NVME_MAX_NR_ALLOCATIONS
557 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^
include/linux/compiler_types.h:538:25: note: in definition of macro '__compiletime_assert'
538 | prefix ## suffix(); \
| ^~~~~~
include/linux/compiler_types.h:557:9: note: in expansion of macro '_compiletime_assert'
557 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:50:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
50 | BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
| ^~~~~~~~~~~~~~~~
drivers/nvme/host/pci.c:3804:9: note: in expansion of macro 'BUILD_BUG_ON'
3804 | BUILD_BUG_ON(nvme_pci_npages_prp() > NVME_MAX_NR_ALLOCATIONS);
| ^~~~~~~~~~~~
Force it to be __always_inline to make sure it is always available for
use with BUILD_BUG_ON().
Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202505061846.12FMyRjj-lkp@intel.com/ Fixes: c372cdd1efdf ("nvme-pci: iod npages fits in s8") Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
It has been reported that when under a bridge with stp_state=1, the logs
get spammed with this message:
[ 251.734607] fsl_dpaa2_eth dpni.5 eth0: Couldn't decode source port
Further debugging shows the following info associated with packets:
source_port=-1, switch_id=-1, vid=-1, vbid=1
In other words, they are data plane packets which are supposed to be
decoded by dsa_tag_8021q_find_port_by_vbid(), but the latter (correctly)
refuses to do so, because no switch port is currently in
BR_STATE_LEARNING or BR_STATE_FORWARDING - so the packet is effectively
unexpected.
The error goes away after the port progresses to BR_STATE_LEARNING in 15
seconds (the default forward_time of the bridge), because then,
dsa_tag_8021q_find_port_by_vbid() can correctly associate the data plane
packets with a plausible bridge port in a plausible STP state.
Re-reading IEEE 802.1D-1990, I see the following:
"4.4.2 Learning: (...) The Forwarding Process shall discard received
frames."
IEEE 802.1D-2004 further clarifies:
"DISABLED, BLOCKING, LISTENING, and BROKEN all correspond to the
DISCARDING port state. While those dot1dStpPortStates serve to
distinguish reasons for discarding frames, the operation of the
Forwarding and Learning processes is the same for all of them. (...)
LISTENING represents a port that the spanning tree algorithm has
selected to be part of the active topology (computing a Root Port or
Designated Port role) but is temporarily discarding frames to guard
against loops or incorrect learning."
Well, this is not what the driver does - instead it sets
mac[port].ingress = true.
To get rid of the log spam, prevent unexpected data plane packets to
be received by software by discarding them on ingress in the LISTENING
state.
In terms of blame attribution: the prints only date back to commit d7f9787a763f ("net: dsa: tag_8021q: add support for imprecise RX based
on the VBID"). However, the settings would permit a LISTENING port to
forward to a FORWARDING port, and the standard suggests that's not OK.
Fixes: 640f763f98c2 ("net: dsa: sja1105: Add support for Spanning Tree Protocol") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20250509113816.2221992-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
There is a situation where after THALT is set high, TGO stays high as
well. Because jiffies are never updated, as we are in a context with
interrupts disabled, we never exit that loop and have a deadlock.
That deadlock was noticed on a sama5d4 device that stayed locked for days.
Use retries instead of jiffies so that the timeout really works and we do
not have a deadlock anymore.
When an event with UMP message is sent to a UMP client, the EP port
receives always no matter where the event is sent to, as it's a
catch-all port. OTOH, if an event is sent to EP port, and if the
event has a certain UMP Group, it should have been delivered to the
associated UMP Group port, too, but this was ignored, so far.
This patch addresses the behavior. Now a UMP event sent to the
Endpoint port will be delivered to the subscribers of the UMP group
port the event is associated with.
The patch also does a bit of refactoring to simplify the code about
__deliver_to_subscribers().
mctp_flow_prepare_output() is called in mctp_route_output(), which
places outbound packets onto a given interface. The packet may represent
a message fragment, in which case we provoke an unbalanced reference
count to the underlying device. This causes trouble if we ever attempt
to remove the interface:
[ 48.702195] usb 1-1: USB disconnect, device number 2
[ 58.883056] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2
[ 69.022548] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2
[ 79.172568] unregister_netdevice: waiting for mctpusb0 to become free. Usage count = 2
...
Predicate the invocation of mctp_dev_set_key() in
mctp_flow_prepare_output() on not already having associated the device
with the key. It's not yet realistic to uphold the property that the key
maintains only one device reference earlier in the transmission sequence
as the route (and therefore the device) may not be known at the time the
key is associated with the socket.
Fixes: 67737c457281 ("mctp: Pass flow data & flow release events to drivers") Acked-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au> Link: https://patch.msgid.link/20250508-mctp-dev-refcount-v1-1-d4f965c67bb5@codeconstruct.com.au Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
In mctp_dump_addrinfo, ifa_index can be used to filter interfaces, but
only when the struct ifaddrmsg is provided. Otherwise it will be
comparing to uninitialised memory - reproducible in the syzkaller case from
dhcpd, or busybox "ip addr show".
The kernel MCTP implementation has always filtered by ifa_index, so
existing userspace programs expecting to dump MCTP addresses must
already be passing a valid ifa_index value (either 0 or a real index).
Fix a crash in the ethtool YNL implementation when Hardware Clock information
is not present in the response. This ensures graceful handling of devices or
drivers that do not provide this optional field. e.g.
Traceback (most recent call last):
File "/net/tools/net/ynl/pyynl/./ethtool.py", line 438, in <module>
main()
~~~~^^
File "/net/tools/net/ynl/pyynl/./ethtool.py", line 341, in main
print(f'PTP Hardware Clock: {tsinfo["phc-index"]}')
~~~~~~^^^^^^^^^^^^^
KeyError: 'phc-index'
Fixes: f3d07b02b2b8 ("tools: ynl: ethtool testing tool") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20250508035414.82974-1-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Previously, when reducing a qdisc's limit via the ->change() operation, only
the main skb queue was trimmed, potentially leaving packets in the gso_skb
list. This could result in NULL pointer dereference when we only check
sch->limit against sch->q.qlen.
This patch introduces a new helper, qdisc_dequeue_internal(), which ensures
both the gso_skb list and the main queue are properly flushed when trimming
excess packets. All relevant qdiscs (codel, fq, fq_codel, fq_pie, hhf, pie)
are updated to use this helper in their ->change() routines.
Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: afe4fd062416 ("pkt_sched: fq: Fair Queue packet scheduler") Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc") Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme") Reported-by: Will <willsroot@protonmail.com> Reported-by: Savy <savy@syst3mfailure.io> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
Device flags could be updated in the meantime while MGMT_OP_ADD_DEVICE
is pending on hci_update_passive_scan_sync so instead of setting the
current_flags as cmd->user_data just do a lookup using
hci_conn_params_lookup and use the latest stored flags.
Fixes: a182d9c84f9c ("Bluetooth: MGMT: Fix Add Device to responding before completing") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
spi_test_print_hex_dump() prints buffers holding less than 1024 bytes in
full. Larger buffers are truncated: only the first 512 and the last 512
bytes are printed, separated by a truncation message. The latter is
confusing in case the buffer holds exactly 1024 bytes, as all data is
printed anyway.
Fix this by printing buffers holding up to and including 1024 bytes in
full.
When memory is insufficient, the allocation of nfs_lock_context in
nfs_get_lock_context() fails and returns -ENOMEM. If we mistakenly treat
an nfs4_unlockdata structure (whose l_ctx member has been set to -ENOMEM)
as valid and proceed to execute rpc_run_task(), this will trigger a NULL
pointer dereference in nfs4_locku_prepare. For example:
Free the allocated nfs4_unlockdata when nfs_get_lock_context() fails and
return NULL to terminate subsequent rpc_run_task, preventing NULL pointer
dereference.
Fixes: f30cb757f680 ("NFS: Always wait for I/O completion before unlock") Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://lore.kernel.org/r/20250417072508.3850532-1-lilingfeng3@huawei.com Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
devm_kasprintf() returns NULL when memory allocation fails. Currently,
uclogic_input_configured() does not check for this case, which results
in a NULL pointer dereference.
Add NULL check after devm_kasprintf() to prevent this issue.
Fixes: dd613a4e45f8 ("HID: uclogic: Correct devm device reference for hidinput input_dev name") Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
In the function rxe_create_cq, when rxe_cq_from_init fails, the function
rxe_cleanup will be called to handle the allocated resources. In fact,
some memory resources have already been freed in the function
rxe_cq_from_init. Thus, this problem will occur.
The solution is to let rxe_cleanup do all the work.
Follow the pattern of other drivers and use aligned_s64 for the
timestamp. This will ensure that the timestamp is correctly aligned on
all architectures.
Fixes: a5bf6fdd19c3 ("iio:chemical:sps30: Fix timestamp alignment") Signed-off-by: David Lechner <dlechner@baylibre.com> Reviewed-by: Nuno Sá <nuno.sa@analog.com> Link: https://patch.msgid.link/20250417-iio-more-timestamp-alignment-v1-5-eafac1e22318@baylibre.com Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
On architectures where an s64 is not 64-bit aligned, this may result
insufficient alignment of the timestamp and the structure being too small.
Use aligned_s64 to force the alignment.
Fixes: a1caeebab07e ("iio: adc: ad7768-1: Fix too small buffer passed to iio_push_to_buffers_with_timestamp()") # aligned_s64 newer Reported-by: David Lechner <dlechner@baylibre.com> Reviewed-by: Nuno Sá <nuno.sa@analog.com> Reviewed-by: David Lechner <dlechner@baylibre.com> Link: https://patch.msgid.link/20250413103443.2420727-3-jic23@kernel.org Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
This breaks S4 because we end up setting the s3/s0ix flags
even when we are entering s4 since prepare is used by both
flows. The causes both the S3/s0ix and s4 flags to be set
which breaks several checks in the driver which assume they
are mutually exclusive.
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3634 Cc: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit ce8f7d95899c2869b47ea6ce0b3e5bf304b2fff4) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
As part of the suspend sequence VRAM needs to be evicted on dGPUs.
In order to make suspend/resume more reliable we moved this into
the pmops prepare() callback so that the suspend sequence would fail
but the system could remain operational under high memory usage suspend.
Another class of issues exist though where due to memory fragementation
there isn't a large enough contiguous space and swap isn't accessible.
Add support for a suspend/hibernate notification callback that could
evict VRAM before tasks are frozen. This should allow paging out to swap
if necessary.
Don't set power state flag when system enter runtime suspend,
or it may cause runtime resume failure issue.
Fixes: 3a9626c816db ("drm/amd: Stop evicting resources on APUs in suspend") Signed-off-by: Ma Jun <Jun.Ma2@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org
Stable-dep-of: d0ce1aaa8531 ("Revert "drm/amd: Stop evicting resources on APUs in suspend"") Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5095d5418193 ("drm/amd: Evict resources during PM ops prepare()
callback") intentionally moved the eviction of resources to earlier in
the suspend process, but this introduced a subtle change that it occurs
before adev->in_s0ix or adev->in_s3 are set. This meant that APUs
actually started to evict resources at suspend time as well.
Explicitly set s0ix or s3 in the prepare() stage, and unset them if the
prepare() stage failed.
v2: squash in warning fix from Stephen Rothwell
Reported-by: Jürg Billeter <j@bitron.ch> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3132#note_2271038 Fixes: 5095d5418193 ("drm/amd: Evict resources during PM ops prepare() callback") Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Stable-dep-of: d0ce1aaa8531 ("Revert "drm/amd: Stop evicting resources on APUs in suspend"") Signed-off-by: Sasha Levin <sashal@kernel.org>
On architectures where an s64 is only 32-bit aligned insufficient padding
would be left between the earlier elements and the timestamp. Use
aligned_s64 to enforce the correct placement and ensure the storage is
large enough.
Fixes: 54e018da3141 ("iio:ad7266: Mark transfer buffer as __be16") # aligned_s64 is much newer. Reported-by: David Lechner <dlechner@baylibre.com> Reviewed-by: Nuno Sá <nuno.sa@analog.com> Reviewed-by: David Lechner <dlechner@baylibre.com> Link: https://patch.msgid.link/20250413103443.2420727-2-jic23@kernel.org Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Previously, commit ed129ec9057f ("KVM: x86: forcibly leave nested mode
on vCPU reset") addressed an issue where a triple fault occurring in
nested mode could lead to use-after-free scenarios. However, the commit
did not handle the analogous situation for System Management Mode (SMM).
This omission results in triggering a WARN when KVM forces a vCPU INIT
after SHUTDOWN interception while the vCPU is in SMM. This situation was
reprodused using Syzkaller by:
1) Creating a KVM VM and vCPU
2) Sending a KVM_SMI ioctl to explicitly enter SMM
3) Executing invalid instructions causing consecutive exceptions and
eventually a triple fault
Architecturally, INIT is blocked when the CPU is in SMM, hence KVM's WARN()
in kvm_vcpu_reset() to guard against KVM bugs, e.g. to detect improper
emulation of INIT. SHUTDOWN on SVM is a weird edge case where KVM needs to
do _something_ sane with the VMCB, since it's technically undefined, and
INIT is the least awful choice given KVM's ABI.
So, double down on stuffing INIT on SHUTDOWN, and force the vCPU out of
SMM to avoid any weirdness (and the WARN).
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: ed129ec9057f ("KVM: x86: forcibly leave nested mode on vCPU reset") Cc: stable@vger.kernel.org Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Mikhail Lobanov <m.lobanov@rosa.ru> Link: https://lore.kernel.org/r/20250414171207.155121-1-m.lobanov@rosa.ru
[sean: massage changelog, make it clear this isn't architectural behavior] Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Currently if an SEV-ES VM shuts down userspace sees KVM_RUN struct with
only errno=EINVAL. This is a very limited amount of information to debug
the situation. Instead return KVM_EXIT_SHUTDOWN to alert userspace the VM
is shutting down and is not usable any further.
Signed-off-by: Peter Gonda <pgonda@google.com> Suggested-by: Sean Christopherson <seanjc@google.com> Suggested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Borislav Petkov <bp@alien8.de> Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20230907162449.1739785-1-pgonda@google.com
[sean: tweak changelog] Signed-off-by: Sean Christopherson <seanjc@google.com>
Stable-dep-of: a2620f8932fa ("KVM: SVM: Forcibly leave SMM mode on SHUTDOWN interception") Signed-off-by: Sasha Levin <sashal@kernel.org>
Polling mode transactions wait for a reply busy-looping without holding a
spinlock, but currently the timeout checks are based only on elapsed time:
as a result we could hit a false positive whenever our busy-looping thread
is pre-empted and scheduled out for a time greater than the polling
timeout.
Change the checks at the end of the busy-loop to make sure that the polling
wasn't indeed successful or an out-of-order reply caused the polling to be
forcibly terminated.
Add the support for counting some of the SCMI communication debug metrics
like how many were sent successfully or with some errors, responses
received, notifications and delayed responses, transfer timeouts and
errors from the firmware/platform.
In many cases, the traces exists. But the traces are not always necessarily
enabled and getting such cumulative SCMI communication debug metrics helps
in understanding if there are any possible improvements that can be made
on either side of SCMI communication.
Since SCMI involves interaction with the entity(software, firmware and/or
hardware) providing services or features, it is quite useful to track
certain metrics(for pure debugging purposes) like how many messages were
sent or received, were there any failures, what kind of failures, ..etc.
Add a new optional config option for the above purpose and the initial
support for counting such key debug metrics.
It is useful to have message dump traces for any invalid/bad/unexpected
replies. Let us add traces for the same as well as late-timed-out,
out-of-order and unexpected/spurious messages.
Upon reception of malformed and unexpected timed-out SCMI messages, it is
not possible to trace those bad messages in their entirety, because usually
we cannot even retrieve the payload, or it is just not reliable.
Add a helper to trace at least the content of the header of the received
message while associating a meaningful tag and error code.
With some Infineon chips the timeouts in tpm_tis_send_data (both B and
C) can reach up to about 2250 ms.
Timeout C is retried since
commit de9e33df7762 ("tpm, tpm_tis: Workaround failed command reception on Infineon devices")
Timeout B still needs to be extended.
The problem is most commonly encountered with context related operation
such as load context/save context. These are issued directly by the
kernel, and there is no retry logic for them.
When a filesystem is set up to use the TPM for unlocking the boot fails,
and restarting the userspace service is ineffective. This is likely
because ignoring a load context/save context result puts the real TPM
state and the TPM state expected by the kernel out of sync.
Chips known to be affected:
tpm_tis IFX1522:00: 2.0 TPM (device-id 0x1D, rev-id 54)
Description: SLB9672
Firmware Revision: 15.22
Since the shared trace_probe_log variable can be accessed and
modified via probe event create operation of kprobe_events,
uprobe_events, and dynamic_events, it should be protected.
In the dynamic_events, all operations are serialized by
`dyn_event_ops_mutex`. But kprobe_events and uprobe_events
interfaces are not serialized.
To solve this issue, introduces dyn_event_create(), which runs
create() operation under the mutex, for kprobe_events and
uprobe_events. This also uses lockdep to check the mutex is
held when using trace_probe_log* APIs.
Link: https://lore.kernel.org/all/174684868120.551552.3068655787654268804.stgit@devnote2/ Reported-by: Paul Cacheux <paulcacheux@gmail.com> Closes: https://lore.kernel.org/all/20250510074456.805a16872b591e2971a4d221@kernel.org/ Fixes: ab105a4fb894 ("tracing: Use tracing error_log with probe events") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Commit ec5fbdfb99d1 ("cgroup/cpuset: Enable update_tasks_cpumask()
on top_cpuset") enabled us to pull CPUs dedicated to child partitions
from tasks in top_cpuset by ignoring per cpu kthreads. However, there
can be other kthreads that are not per cpu but have PF_NO_SETAFFINITY
flag set to indicate that we shouldn't mess with their CPU affinity.
For other kthreads, their affinity will be changed to skip CPUs dedicated
to child partitions whether it is an isolating or a scheduling one.
As all the per cpu kthreads have PF_NO_SETAFFINITY set, the
PF_NO_SETAFFINITY tasks are essentially a superset of per cpu kthreads.
Fix this issue by dropping the kthread_is_per_cpu() check and checking
the PF_NO_SETAFFINITY flag instead.
(1), (2) means that the model has hardware GPIO for WLAN, you can call
WMIMethod(DEVS, 0x00010011, 1 or 0) to turn WLAN on/off.
(3), (4) means that the model doesn’t have hardware GPIO, you need to use
API or driver library to turn WLAN on/off, and call
WMIMethod(DEVS, 0x00010012, 1 or 0) to set WLAN LED status.
After you set WLAN LED status, you can see the WLAN status is changed with
WMIMethod(DSTS, 0x00010011). Because the status is recorded lastly
(ex: Windows), you can use it for synchronization.
(5) means that the model doesn’t have WLAN device.
WLAN is the ONLY special case with upper rule.
"""
The wlan_ctrl_by_user flag should be set on 0x0003000? ((3), (4) above)
return values, but the flag mistakenly also gets set on laptops with
0x0005000? ((1), (2)) return values. This is causing rfkill problems on
laptops where 0x0005000? is returned.
Fix the check to only set the wlan_ctrl_by_user flag for 0x0003000?
return values.
MECHREVO Wujie 14XA (GX4HRXL) wakes up immediately after s2idle entry.
This happens regardless of whether the laptop is plugged into AC power,
or whether any peripheral is plugged into the laptop.
Similar to commit a55bdad5dfd1 ("platform/x86/amd/pmc: Disable keyboard
wakeup on AMD Framework 13"), the MECHREVO Wujie 14XA wakes up almost
instantly after s2idle suspend entry (IRQ1 is the keyboard):
2025-04-18 17:23:57,588 DEBUG: PM: Triggering wakeup from IRQ 9
2025-04-18 17:23:57,588 DEBUG: PM: Triggering wakeup from IRQ 1
Add this model to the spurious_8042 quirk to workaround this.
This patch does not affect the wake-up function of the built-in keyboard.
Because the firmware of this machine adds an insurance for keyboard
wake-up events, as it always triggers an additional IRQ 9 to wake up the
system.
Suggested-by: Mingcong Bai <jeffbai@aosc.io> Suggested-by: Xinhui Yang <cyan@cyano.uk> Suggested-by: Rong Zhang <i@rong.moe> Fixes: a55bdad5dfd1 ("platform/x86/amd/pmc: Disable keyboard wakeup on AMD Framework 13") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4166 Cc: Mario Limonciello <mario.limonciello@amd.com> Link: https://zhuanldan.zhihu.com/p/730538041 Tested-by: Yemu Lu <prcups@krgm.moe> Signed-off-by: Runhua He <hua@aosc.io> Link: https://lore.kernel.org/r/20250507100103.995395-1-hua@aosc.io Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
In commit bbdc6076d2e5 ("binfmt_elf: move brk out of mmap when doing
direct loader exec"), the brk was moved out of the mmap region when
loading static PIE binaries (ET_DYN without INTERP). The common case
for these binaries was testing new ELF loaders, so the brk needed to
be away from mmap to avoid colliding with stack, future mmaps (of the
loader-loaded binary), etc. But this was only done when ASLR was enabled,
in an attempt to minimize changes to memory layouts.
After adding support to respect alignment requirements for static PIE
binaries in commit 3545deff0ec7 ("binfmt_elf: Honor PT_LOAD alignment
for static PIE"), it became possible to have a large gap after the
final PT_LOAD segment and the top of the mmap region. This means that
future mmap allocations might go after the last PT_LOAD segment (where
brk might be if ASLR was disabled) instead of before them (where they
traditionally ended up).
On arm64, running with ASLR disabled, Ubuntu 22.04's "ldconfig" binary,
a static PIE, has alignment requirements that leaves a gap large enough
after the last PT_LOAD segment to fit the vdso and vvar, but still leave
enough space for the brk (which immediately follows the last PT_LOAD
segment) to be allocated by the binary.
After commit 0b3bc3354eb9 ("arm64: vdso: Switch to generic storage
implementation"), the arm64 vvar grew slightly, and suddenly the brk
collided with the allocation.
The solution is to unconditionally move the brk out of the mmap region
for static PIE binaries. Whether ASLR is enabled or not does not change if
there may be future mmap allocation collisions with a growing brk region.
Update memory layout comments (with kernel-doc headings), consolidate
the setting of mm->brk to later (it isn't needed early), move static PIE
brk out of mmap unconditionally, and make sure brk(2) knows to base brk
position off of mm->start_brk not mm->end_data no matter what the cause of
moving it is (via current->brk_randomized).
For the CONFIG_COMPAT_BRK case, though, leave the logic unchanged, as we
can never safely move the brk. These systems, however, are not using
specially aligned static PIE binaries.
Reported-by: Ryan Roberts <ryan.roberts@arm.com> Closes: https://lore.kernel.org/lkml/f93db308-4a0e-4806-9faf-98f890f5a5e6@arm.com/ Fixes: bbdc6076d2e5 ("binfmt_elf: move brk out of mmap when doing direct loader exec") Link: https://lore.kernel.org/r/20250425224502.work.520-kees@kernel.org Reviewed-by: Ryan Roberts <ryan.roberts@arm.com> Tested-by: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The p_align values in PT_LOAD were ignored for static PIE executables
(i.e. ET_DYN without PT_INTERP). This is because there is no way to
request a non-fixed mmap region with a specific alignment. ET_DYN with
PT_INTERP uses a separate base address (ELF_ET_DYN_BASE) and binfmt_elf
performs the ASLR itself, which means it can also apply alignment. For
the mmap region, the address selection happens deep within the vm_mmap()
implementation (when the requested address is 0).
The earlier attempt to implement this:
commit 9630f0d60fec ("fs/binfmt_elf: use PT_LOAD p_align values for static PIE")
commit 925346c129da ("fs/binfmt_elf: fix PT_LOAD p_align values for loaders")
did not take into account the different base address origins, and were
eventually reverted:
aeb7923733d1 ("revert "fs/binfmt_elf: use PT_LOAD p_align values for static PIE"")
In order to get the correct alignment from an mmap base, binfmt_elf must
perform a 0-address load first, then tear down the mapping and perform
alignment on the resulting address. Since this is slightly more overhead,
only do this when it is needed (i.e. the alignment is not the default
ELF alignment). This does, however, have the benefit of being able to
use MAP_FIXED_NOREPLACE, to avoid potential collisions.
With this fixed, enable the static PIE self tests again.
Reported-by: H.J. Lu <hjl.tools@gmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=215275 Link: https://lore.kernel.org/r/20240508173149.677910-3-keescook@chromium.org Signed-off-by: Kees Cook <kees@kernel.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled") Signed-off-by: Sasha Levin <sashal@kernel.org>
In preparation to support PT_LOAD with large p_align values on
non-PT_INTERP ET_DYN executables (i.e. "static pie"), we'll need to use
the total_size details earlier. Move this separately now to make the
next patch more readable. As total_size and load_bias are currently
calculated separately, this has no behavioral impact.
After commit 4d1cd3b2c5c1 ("tools/testing/selftests/exec: fix link
error"), the load address alignment tests tried to build statically.
This was silently ignored in some cases. However, after attempting to
further fix the build by switching to "-static-pie", the test started
failing. This appears to be due to non-PT_INTERP ET_DYN execs ("static
PIE") not doing alignment correctly, which remains unfixed[1]. See commit aeb7923733d1 ("revert "fs/binfmt_elf: use PT_LOAD p_align values for
static PIE"") for more details.
Provide rules to build both static and non-static PIE binaries, improve
debug reporting, and perform several test steps instead of a single
all-or-nothing test. However, do not actually enable static-pie tests;
alignment specification is only supported for ET_DYN with PT_INTERP
("regular PIE").
Currently the brk starts its randomization immediately after .bss,
which means there is a chance that when the random offset is 0, linear
overflows from .bss can reach into the brk area. Leave at least a single
page gap between .bss and brk (when it has not already been explicitly
relocated into the mmap range).
Reported-by: <y0un9n132@gmail.com> Closes: https://lore.kernel.org/linux-hardening/CA+2EKTVLvc8hDZc+2Yhwmus=dzOUG5E4gV7ayCbu0MPJTZzWkw@mail.gmail.com/ Link: https://lore.kernel.org/r/20240217062545.1631668-2-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled") Signed-off-by: Sasha Levin <sashal@kernel.org>
With the BSS handled generically via the new filesz/memsz mismatch
handling logic in elf_load(), elf_bss no longer needs to be tracked.
Drop the variable.
Cc: Eric Biederman <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: linux-fsdevel@vger.kernel.org Cc: linux-mm@kvack.org Suggested-by: Eric Biederman <ebiederm@xmission.com> Tested-by: Pedro Falcato <pedro.falcato@gmail.com> Signed-off-by: Sebastian Ott <sebott@redhat.com> Link: https://lore.kernel.org/r/20230929032435.2391507-2-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled") Signed-off-by: Sasha Levin <sashal@kernel.org>
Implement a helper elf_load() that wraps elf_map() and performs all
of the necessary work to ensure that when "memsz > filesz" the bytes
described by "memsz > filesz" are zeroed.
An outstanding issue is if the first segment has filesz 0, and has a
randomized location. But that is the same as today.
In this change I replaced an open coded padzero() that did not clear
all of the way to the end of the page, with padzero() that does.
I also stopped checking the return of padzero() as there is at least
one known case where testing for failure is the wrong thing to do.
It looks like binfmt_elf_fdpic may have the proper set of tests
for when error handling can be safely completed.
I found a couple of commits in the old history
https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git,
that look very interesting in understanding this code.
commit 39b56d902bf3 ("[PATCH] binfmt_elf: clearing bss may fail")
commit c6e2227e4a3e ("[SPARC64]: Missing user access return value checks in fs/binfmt_elf.c and fs/compat.c")
commit 5bf3be033f50 ("v2.4.10.1 -> v2.4.10.2")
Looking at commit 39b56d902bf3 ("[PATCH] binfmt_elf: clearing bss may fail"):
> commit 39b56d902bf35241e7cba6cc30b828ed937175ad
> Author: Pavel Machek <pavel@ucw.cz>
> Date: Wed Feb 9 22:40:30 2005 -0800
>
> [PATCH] binfmt_elf: clearing bss may fail
>
> So we discover that Borland's Kylix application builder emits weird elf
> files which describe a non-writeable bss segment.
>
> So remove the clear_user() check at the place where we zero out the bss. I
> don't _think_ there are any security implications here (plus we've never
> checked that clear_user() return value, so whoops if it is a problem).
>
> Signed-off-by: Pavel Machek <pavel@suse.cz>
> Signed-off-by: Andrew Morton <akpm@osdl.org>
> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It seems pretty clear that binfmt_elf_fdpic with skipping clear_user() for
non-writable segments and otherwise calling clear_user(), aka padzero(),
and checking it's return code is the right thing to do.
I just skipped the error checking as that avoids breaking things.
And notably, it looks like Borland's Kylix died in 2005 so it might be
safe to just consider read-only segments with memsz > filesz an error.
Reported-by: Sebastian Ott <sebott@redhat.com> Reported-by: Thomas Weißschuh <linux@weissschuh.net> Closes: https://lkml.kernel.org/r/20230914-bss-alloc-v1-1-78de67d2c6dd@weissschuh.net Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Link: https://lore.kernel.org/r/87sf71f123.fsf@email.froward.int.ebiederm.org Tested-by: Pedro Falcato <pedro.falcato@gmail.com> Signed-off-by: Sebastian Ott <sebott@redhat.com> Link: https://lore.kernel.org/r/20230929032435.2391507-1-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org>
Stable-dep-of: 11854fe263eb ("binfmt_elf: Move brk for static PIE even if ASLR disabled") Signed-off-by: Sasha Levin <sashal@kernel.org>
The vfs has long had a fallback to obtain the security.* xattrs from the
LSM when the filesystem does not implement its own listxattr, but
shmem/tmpfs and kernfs later gained their own xattr handlers to support
other xattrs. Unfortunately, as a side effect, tmpfs and kernfs-based
filesystems like sysfs no longer return the synthetic security.* xattr
names via listxattr unless they are explicitly set by userspace or
initially set upon inode creation after policy load. coreutils has
recently switched from unconditionally invoking getxattr for security.*
for ls -Z via libselinux to only doing so if listxattr returns the xattr
name, breaking ls -Z of such inodes.
FineIBT-paranoid was using the retpoline bytes for the paranoid check,
disabling retpolines, because all parts that have IBT also have eIBRS
and thus don't need no stinking retpolines.
Except... ITS needs the retpolines for indirect calls must not be in
the first half of a cacheline :-/
<fineibt_paranoid_start>:
0: 41 ba 78 56 34 12 mov $0x12345678, %r10d
6: 45 3b 53 f7 cmp -0x9(%r11), %r10d
a: 4d 8d 5b f0 lea -0x10(%r11), %r11
e: 2e e8 XX XX XX XX cs call __x86_indirect_paranoid_thunk_r11
Where the paranoid_thunk looks like:
1d: <ea> (bad)
__x86_indirect_paranoid_thunk_r11:
1e: 75 fd jne 1d
__x86_indirect_its_thunk_r11:
20: 41 ff eb jmp *%r11
23: cc int3
[ dhansen: remove initialization to false ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
[ Just a portion of the original commit, in order to fix a build issue
in stable kernels due to backports ] Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Link: https://lore.kernel.org/r/20250514113952.GB16434@noisy.programming.kicks-ass.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ITS mitigation moves the unsafe indirect branches to a safe thunk. This
could degrade the prediction accuracy as the source address of indirect
branches becomes same for different execution paths.
To improve the predictions, and hence the performance, assign a separate
thunk for each indirect callsite. This is also a defense-in-depth measure
to avoid indirect branches aliasing with each other.
As an example, 5000 dynamic thunks would utilize around 16 bits of the
address space, thereby gaining entropy. For a BTB that uses
32 bits for indexing, dynamic thunks could provide better prediction
accuracy over fixed thunks.
Have ITS thunks be variable sized and use EXECMEM_MODULE_TEXT such that
they are both more flexible (got to extend them later) and live in 2M TLBs,
just like kernel code, avoiding undue TLB pressure.
[ pawan: CONFIG_EXECMEM and CONFIG_EXECMEM_ROX are not supported on
backport kernel, made changes to use module_alloc() and
set_memory_*() for dynamic thunks. ]
cfi_rewrite_callers() updates the fineIBT hash matching at the caller side,
but except for paranoid-mode it relies on apply_retpoline() and friends for
any ENDBR relocation. This could temporarily cause an indirect branch to
land on a poisoned ENDBR.
For instance, with para-virtualization enabled, a simple wrmsrl() could
have an indirect branch pointing to native_write_msr() who's ENDBR has been
relocated due to fineIBT:
Such an indirect call during the alternative patching could #CP if the
caller is not *yet* adjusted for the new target ENDBR. To prevent a false
#CP, keep CET-IBT disabled until all callers are patched.
Patching during the module load does not need to be guarded by IBT-disable
because the module code is not executed until the patching is complete.
[ pawan: Since apply_paravirt() happens before __apply_fineibt()
relocates the ENDBR, pv_ops in the example above is not relevant.
It is still safer to keep this commit because missing an ENDBR
means an oops. ]
The software mitigation for BHI is to execute BHB clear sequence at syscall
entry, and possibly after a cBPF program. ITS mitigation thunks RETs in the
lower half of the cacheline. This causes the RETs in the BHB clear sequence
to be thunked as well, adding unnecessary branches to the BHB clear
sequence.
Since the sequence is in hot path, align the RET instructions in the
sequence to avoid thunking.
This is how disassembly clear_bhb_loop() looks like after this change:
When retpoline mitigation is enabled for spectre-v2, enabling
call-depth-tracking and RSB stuffing also mitigates ITS. Add cmdline option
indirect_target_selection=stuff to allow enabling RSB stuffing mitigation.
When retpoline mitigation is not enabled, =stuff option is ignored, and
default mitigation for ITS is deployed.
Ice Lake generation CPUs are not affected by guest/host isolation part of
ITS. If a user is only concerned about KVM guests, they can now choose a
new cmdline option "vmexit" that will not deploy the ITS mitigation when
CPU is not affected by guest/host isolation. This saves the performance
overhead of ITS mitigation on Ice Lake gen CPUs.
When "vmexit" option selected, if the CPU is affected by ITS guest/host
isolation, the default ITS mitigation is deployed.
Indirect Target Selection (ITS) is a bug in some pre-ADL Intel CPUs with
eIBRS. It affects prediction of indirect branch and RETs in the
lower half of cacheline. Due to ITS such branches may get wrongly predicted
to a target of (direct or indirect) branch that is located in the upper
half of the cacheline.
Scope of impact
===============
Guest/host isolation
--------------------
When eIBRS is used for guest/host isolation, the indirect branches in the
VMM may still be predicted with targets corresponding to branches in the
guest.
Intra-mode
----------
cBPF or other native gadgets can be used for intra-mode training and
disclosure using ITS.
User/kernel isolation
---------------------
When eIBRS is enabled user/kernel isolation is not impacted.
Indirect Branch Prediction Barrier (IBPB)
-----------------------------------------
After an IBPB, indirect branches may be predicted with targets
corresponding to direct branches which were executed prior to IBPB. This is
mitigated by a microcode update.
Add cmdline parameter indirect_target_selection=off|on|force to control the
mitigation to relocate the affected branches to an ITS-safe thunk i.e.
located in the upper half of cacheline. Also add the sysfs reporting.
When retpoline mitigation is deployed, ITS safe-thunks are not needed,
because retpoline sequence is already ITS-safe. Similarly, when call depth
tracking (CDT) mitigation is deployed (retbleed=stuff), ITS safe return
thunk is not used, as CDT prevents RSB-underflow.
To not overcomplicate things, ITS mitigation is not supported with
spectre-v2 lfence;jmp mitigation. Moreover, it is less practical to deploy
lfence;jmp mitigation on ITS affected parts anyways.
RETs in the lower half of cacheline may be affected by ITS bug,
specifically when the RSB-underflows. Use ITS-safe return thunk for such
RETs.
RETs that are not patched:
- RET in retpoline sequence does not need to be patched, because the
sequence itself fills an RSB before RET.
- RET in Call Depth Tracking (CDT) thunks __x86_indirect_{call|jump}_thunk
and call_depth_return_thunk are not patched because CDT by design
prevents RSB-underflow.
- RETs in .init section are not reachable after init.
- RETs that are explicitly marked safe with ANNOTATE_UNRET_SAFE.
Due to ITS, indirect branches in the lower half of a cacheline may be
vulnerable to branch target injection attack.
Introduce ITS-safe thunks to patch indirect branches in the lower half of
cacheline with the thunk. Also thunk any eBPF generated indirect branches
in emit_indirect_jump().
Below category of indirect branches are not mitigated:
- Indirect branches in the .init section are not mitigated because they are
discarded after boot.
- Indirect branches that are explicitly marked retpoline-safe.
Note that retpoline also mitigates the indirect branches against ITS. This
is because the retpoline sequence fills an RSB entry before RET, and it
does not suffer from RSB-underflow part of the ITS.
ITS bug in some pre-Alderlake Intel CPUs may allow indirect branches in the
first half of a cache line get predicted to a target of a branch located in
the second half of the cache line.
Set X86_BUG_ITS on affected CPUs. Mitigation to follow in later commits.
projects / thirdparty / kernel / stable.git / log
