hid_bpf_get_data() returns a pointer into the HID-BPF context data when
the caller-provided offset and size fit inside ctx->allocated_size.
The current check adds rdwr_buf_size and offset before comparing the
result against ctx->allocated_size. Since both values are unsigned, a
very large size can wrap the sum below ctx->allocated_size and make the
helper return a pointer even though the requested range is not contained
in the backing buffer.
Use check_add_overflow() to reject wrapped range ends before comparing
the requested range end against ctx->allocated_size.
Fixes: 658ee5a64f ("HID: bpf: allocate data memory for device_event BPF programs")
Signed-off-by: Yiyang Chen <chenyy23@mails.tsinghua.edu.cn>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Add support for Maili TLMM configuration and control via the pinctrl
framework.
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com>
Acked-by: Linus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260622-maili-pinctrl-v3-2-9724e1000471@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
The Top Level Mode Multiplexer (TLMM) in the Qualcomm Maili SoC provides
GPIO and pinctrl functionality for UFS, SDC and 226 GPIO pins.
Add a DeviceTree binding to describe the TLMM block on Qualcomm's Maili
SoC.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Jingyi Wang <jingyi.wang@oss.qualcomm.com>
Acked-by: Linus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260622-maili-pinctrl-v3-1-9724e1000471@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
grant_references() allocates a private grant-reference head before
claiming references for the page directory and, for guest-owned buffers,
the data pages. The success path frees the remaining head, but claim
failures and grant_refs_for_buffer() errors return immediately.
Unwind through a common exit path so the private grant-reference head is
released even when granting fails part-way through setup. The caller
still tears down any references already stored in buf->grefs.
Signed-off-by: Yousef Alhouseen <alhouseenyousef@gmail.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260629160517.29340-1-alhouseenyousef@gmail.com>
When gntdev_ioctl_map_grant_ref() fails to copy the operation result
back to userspace after successfully adding the mapping to the list,
the error path returns -EFAULT without releasing the reference
acquired by gntdev_alloc_map(). The mapping remains in priv->maps
with a refcount of 1, causing a memory leak and a dangling list
entry.
Additionally, gntdev_add_map() may modify map->index to avoid overlap
with existing mappings. Therefore, the index returned to userspace
must be obtained after gntdev_add_map() completes.
Fix this by holding the mutex across gntdev_add_map(), retrieving
the correct index, and copy_to_user(). If copy_to_user() fails,
remove the mapping from the list and release the reference while
still holding the lock.
Cc: stable@vger.kernel.org
Fix these issues by properly handling all error cases.
Fixes: 1401c00e59 ("xen/gntdev: convert priv->lock to a mutex")
Fixes: 68b025c813 ("xen-gntdev: Add reference counting to maps")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260622112541.38194-1-vulab@iscas.ac.cn>
While the GCC and Clang compilers already define __ASSEMBLER__
automatically when compiling assembly code, __ASSEMBLY__ is a
macro that only gets defined by the Makefiles in the kernel.
This can be very confusing when switching between userspace
and kernelspace coding, or when dealing with uapi headers that
rather should use __ASSEMBLER__ instead. So let's standardize now
on the __ASSEMBLER__ macro that is provided by the compilers.
This is a completely mechanical patch (done with a simple "sed -i"
statement).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260619114547.159637-1-thuth@redhat.com>
pvcalls_front_event_handler() takes req_id directly from the
backend-supplied ring response and uses it to index the fixed-size
bedata->rsp[] array for a memcpy() and a store, with no range check. A
malicious or buggy backend can set req_id past PVCALLS_NR_RSP_PER_RING
and drive an out-of-bounds write past the bedata allocation.
req_id was also declared int while the wire field rsp->req_id is u32, so
a range check on the signed value alone is insufficient: a backend
req_id of 0xffffffff becomes -1, passes a >= PVCALLS_NR_RSP_PER_RING
test and indexes bedata->rsp[-1]. Declare req_id as u32 so a single
bound covers both ends.
A backend that sends an out-of-range req_id has violated the wire
protocol, so rather than silently dropping the response, log once and
stop trusting the backend: set bedata->disabled. The event handler then
ignores further responses, and the request paths that wait for a
response return -EIO instead of blocking forever. This mirrors the
fatal-error handling xen-netback uses (xenvif_fatal_tx_err()).
The pvcalls frontend currently trusts its backend, so this is not a
classic-Xen security issue, but it matters for hardening PV frontends
against malicious backends (confidential and disaggregated deployments).
Fixes: 2195046bfd ("xen/pvcalls: implement socket command and handle events")
Suggested-by: Juergen Gross <jgross@suse.com>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260617014149.2647404-1-michael.bommarito@gmail.com>
Commit 28f2406838 ("pinctrl: meson: mark the GPIO controller as
sleeping") set gpio_chip.can_sleep = true to work around
gpio-shared-proxy holding a spinlock across a sleeping pinctrl config
path. That locking bug is now fixed in the shared-proxy itself ("gpio:
shared-proxy: always serialize with a sleeping mutex"), so the
controller-wide workaround is no longer needed; the meson GPIO
controller does not sleep.
meson_gpio_get/set/direction_* access MMIO through regmap. The
regmap_mmio bus uses fast I/O (spinlock) locking, so these value
callbacks do not contain sleeping operations. Since gpio_chip.can_sleep
describes the get/set value path, restore can_sleep = false.
Marking the controller sleeping also broke atomic value consumers such
as w1-gpio (1-Wire bitbang): w1_io.c runs its read time slot under
local_irq_save() and uses the non-cansleep gpiod_set_value() /
gpiod_get_value(), which with can_sleep=true trigger WARN_ON(can_sleep)
in gpiolib on every transferred bit (from w1_gpio_write_bit() /
w1_gpio_read_bit() via w1_reset_bus() and w1_search()). The printk and
stack dump inside the IRQs-off, microsecond-scale time slot destroy the
bit timing, so reset/presence detection and ROM search fail: the bus
master registers but w1_master_slave_count stays at 0 and no devices
are found. Verified on an Amlogic A113X board (DS18B20 on GPIOA_14):
with can_sleep restored to false the warnings are gone and the sensor
is detected and read again.
This must not be applied or backported without the shared-proxy locking
fix above; otherwise the original Khadas VIM3 splat returns on boards
that genuinely share a meson GPIO.
Fixes: 28f2406838 ("pinctrl: meson: mark the GPIO controller as sleeping")
Link: https://lore.kernel.org/all/20260105150509.56537-1-bartosz.golaszewski@oss.qualcomm.com/
Signed-off-by: Viacheslav Bocharov <v@baodeep.com>
Acked-by: Linus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260625115718.1678991-3-v@baodeep.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Pins 143 and 151 were not included in the PDC wakeup map. They are
normally used for PCIe2A and PCIe3a PERST# respectively, so they're
unlikely to be excercised in practice, but still add them for the sake
of completeness.
Fixes: c0e4c71a9e ("pinctrl: qcom: Introduce sc8280xp TLMM driver")
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://patch.msgid.link/20260626-topic-8280_pinctrl_wakeup-v1-1-2ccb267148f5@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Out of memory situation on driver's probe is expected to be reported to
the driver's framework with a proper -ENOMEM error code.
Fixes: 35570ac603 ("gpio: add GPIO driver for the Timberdale FPGA")
Signed-off-by: Vladimir Zapolskiy <vz@kernel.org>
Link: https://patch.msgid.link/20260630145148.4081967-1-vz@kernel.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Sang-Heon Jeon <ekffu200098@gmail.com> says:
treewide: remove unnecessary invalid range checks in memblock iteration loops
The memblock API guarantees that for_each_mem_range() and
for_each_mem_pfn_range() never return an invalid range, meaning start is
always less than end.
Several memblock callers still have unnecessary invalid range checks in
their loop bodies, so remove them.
Patches 1-6 cover for_each_mem_range() callers. memblock never stores a
zero-size region, so the range it returns always has start < end. Some
callers apply __va() or __phys_to_virt() before comparing, but these keep
start < end too, so the check is unreachable.
Patches 7-8 cover for_each_mem_pfn_range() callers. __next_mem_pfn_range()
skips any region that does not contain a whole page, so it only ever returns
start_pfn < end_pfn and the check is unnecessary.
For reference, commit 36ca7f4be8 ("arm64: mm: Remove bogus stop
condition from map_mem() loop") did a similar cleanup in arm64 map_mem().
* patches from https://patch.msgid.link/20260630150413.1718632-1-ekffu200098@gmail.com
arm64: mm: remove unreachable invalid range check in kasan_init_shadow()
LoongArch: remove unreachable invalid range check in kasan_init()
riscv: remove unreachable invalid range check in
create_linear_mapping_page_table()
riscv: remove unreachable invalid range check in kasan_init()
ARM: remove unreachable invalid range check in kasan_init()
powerpc64/kasan: Remove unreachable invalid range check in
kasan_init_phys_region()
mm: remove unnecessary empty range check in early_calculate_totalpages()
mm/hugetlb: remove unnecessary empty range check in
hugetlb_bootmem_set_nodes()
Link: https://patch.msgid.link/20260630150413.1718632-1-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
hugetlb_bootmem_set_nodes() iterates the memory ranges with
for_each_mem_pfn_range() and calls node_set(nid, hugetlb_bootmem_nodes)
only when end_pfn > start_pfn. for_each_mem_pfn_range() never returns an
empty range, so start_pfn < end_pfn always.
Therefore the check is unnecessary, so remove it. start_pfn and end_pfn
are no longer used, so remove the local variables.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Link: https://patch.msgid.link/20260630150413.1718632-9-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
early_calculate_totalpages() iterates the memory ranges with
for_each_mem_pfn_range() and calls node_set_state(nid, N_MEMORY) only when
end_pfn - start_pfn is non-zero. for_each_mem_pfn_range() never returns an
empty range, so start_pfn < end_pfn always.
Therefore the check is unnecessary, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Link: https://patch.msgid.link/20260630150413.1718632-8-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
kasan_init() maps each memblock region with for_each_mem_range() and passes
it to kasan_init_phys_region(), which does nothing when start >= end.
for_each_mem_range() never returns an invalid range, so start < end always.
Therefore the start >= end check is unreachable, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-7-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
kasan_init() maps each memblock region with for_each_mem_range(), which
guarantees pa_start < pa_end. Then it skips any region with
pa_start >= arm_lowmem_limit, so pa_start < arm_lowmem_limit is guaranteed
as well.
When pa_end <= arm_lowmem_limit, pa_start < pa_end means start < end, so
the start >= end check is unreachable.
When pa_end > arm_lowmem_limit, end is clamped to __va(arm_lowmem_limit),
and pa_start < arm_lowmem_limit means start < end, so the check is
unreachable as well.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-6-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
kasan_init() populates the linear mapping shadow with for_each_mem_range()
and breaks the loop when start >= end. for_each_mem_range() never returns
an invalid range, so start < end always.
Therefore the start >= end check is unreachable, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Reviewed-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-5-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
create_linear_mapping_page_table() iterates memblock regions with
for_each_mem_range() and breaks the loop when start >= end.
for_each_mem_range() never returns an invalid range, so start < end always.
Therefore the start >= end check is unreachable, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-4-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
kasan_init() populates the linear mapping shadow with for_each_mem_range()
and breaks the loop when start >= end. for_each_mem_range() never returns
an invalid range, so start < end always.
Therefore the start >= end check is unreachable, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-3-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
kasan_init_shadow() maps each memblock region with for_each_mem_range()
and breaks the loop when start >= end. for_each_mem_range() never returns
an invalid range, so start < end always.
Therefore the start >= end check is unreachable, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-2-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
While the panel_type from LFP Data Block is range checked, panel_type2
is not. Add a few helpers for range checking, and use them to not only
check panel_type2, but also improve clarity and correctness in the panel
type selection.
Discovered using AI-assisted static analysis confirmed by Intel Product
Security.
v2:
- Fix commit message typo (Michał)
- Add is_panel_type_pnp() (Ville)
Reported-by: Martin Hodo <martin.hodo@intel.com>
Fixes: 6434cf6300 ("drm/i915/bios: calculate panel type as per child device index in VBT")
Cc: stable@vger.kernel.org # v6.0+
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Ville Syrjälä <ville.syrjala@intel.com>
Reviewed-by: Michał Grzelak <michal.grzelak@intel.com> # v1
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20260626140155.1389655-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit c9ebe5d2f2)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Ensure the EDID provided min/max vfreq are valid. Most scenarios are
already covered (by coincidence) through the checks in
intel_vrr_is_capable() and intel_vrr_is_in_range(), but be more explicit
about it. At worst, a zero min_vfreq could lead to a division by zero in
intel_vrr_compute_vmax().
Discovered using AI-assisted static analysis confirmed by Intel Product
Security.
Reported-by: Martin Hodo <martin.hodo@intel.com>
Fixes: 117cd09ba5 ("drm/i915/display/dp: Compute VRR state in atomic_check")
Cc: stable@vger.kernel.org # v5.12+
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patch.msgid.link/20260625131040.1051272-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit 1765cf59f5)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
When endpoint mode is built-in, but pwrctrl support is in a loadable
module, the imx driver fails to build because the unused host
support still tries to link against pwrctrl:
ld.lld: error: undefined symbol: pci_pwrctrl_power_off_devices
>>> referenced by pci-imx6.c:1988 (drivers/pci/controller/dwc/pci-imx6.c:1988)
>>> drivers/pci/controller/dwc/pci-imx6.o:(imx_pcie_shutdown) in archive vmlinux.a
Add one more select for this.
Fixes: 85c1fcfa74 ("PCI: imx6: Integrate new pwrctrl API")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://patch.msgid.link/20260618143629.2035247-1-arnd@kernel.org
When CONFIG_PCI_HOST_COMMON is set to =m, the i.MX6 PCIe driver
fails to link. This can happen when only i.MX endpoint mode is
enabled but not host mode, which would indirectly enable the
host-common driver itself.
ld.lld: error: undefined symbol: pci_host_common_parse_ports
>>> referenced by pci-imx6.c
>>> drivers/pci/controller/dwc/pci-imx6.o:(imx_pcie_host_init) in archive vmlinux.a
ld.lld: error: undefined symbol: pci_host_common_delete_ports
>>> referenced by pci-imx6.c
>>> drivers/pci/controller/dwc/pci-imx6.o:(imx_pcie_host_init) in archive vmlinux.a
>>> referenced by pci-imx6.c
>>> drivers/pci/controller/dwc/pci-imx6.o:(imx_pcie_host_init) in archive vmlinux.a
Select the common module from the endpoint support directly.
Fixes: 250eea5c06 ("PCI: imx6: Parse 'reset-gpios' in Root Port nodes")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260616164049.3656435-1-arnd@kernel.org
- fprobe: Fix stability and spelling typos
. Fix NULL pointer dereference in fprobe_fgraph_entry(): Prevent general
protection faults by checking shadow-stack reservation bounds. Skip
mid-flight registered fprobes that were not counted during sizing.
- eprobe: Fix string pointer extraction
. Correct the casting of string pointers read from the ringbuffer to
prevent truncation of base event pointer variables when dereferencing
FILTER_PTR_STRING fields.
- tracing/probes: Clean up argument parsing and BTF helper logic
. Make the $ prefix mandatory for comm access: Require the $ prefix for
special fetcharg variables like $comm and $COMM, preventing naming
conflicts with regular BTF-based event fields.
. Fix double addition of offset for @+FOFFSET: Clear the temporary offset
variable after setting the FETCH_OP_FOFFS instruction to avoid applying
the offset multiple times.
. Remove WARN_ON_ONCE from parse_btf_arg: Prevent triggering a kernel warning
via user-space input when creating a kprobe event on a raw address.
. Fix typo in a log message: Correct a spelling error ("$-valiable") in
trace probe log messages.
- samples/trace_events: Improve error checking
. Validate the thread pointer returned from kthread_run() in the trace
events sample code to properly handle thread creation failures.
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Merge tag 'probes-fixes-v7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fixes from Masami Hiramatsu:
"fprobe fixes and spelling typos:
- Fix NULL pointer dereference in fprobe_fgraph_entry(). Prevent
general protection faults by checking shadow-stack reservation
bounds. Skip mid-flight registered fprobes that were not counted
during sizing.
eprobe: fix string pointer extraction
- Correct the casting of string pointers read from the ringbuffer to
prevent truncation of base event pointer variables when
dereferencing FILTER_PTR_STRING fields.
tracing/probes: clean up argument parsing and BTF helper logic
- Make the $ prefix mandatory for comm access: Require the $ prefix
for special fetcharg variables like $comm and $COMM, preventing
naming conflicts with regular BTF-based event fields.
- Fix double addition of offset for @+FOFFSET: Clear the temporary
offset variable after setting the FETCH_OP_FOFFS instruction to
avoid applying the offset multiple times.
- Remove WARN_ON_ONCE from parse_btf_arg: Prevent triggering a kernel
warning via user-space input when creating a kprobe event on a raw
address.
- Fix typo in a log message: Correct a spelling error ("$-valiable")
in trace probe log messages.
samples/trace_events: improve error checking
- Validate the thread pointer returned from kthread_run() in the
trace events sample code to properly handle thread creation
failures"
* tag 'probes-fixes-v7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/probes: Make the $ prefix mandatory for comm access
tracing/fprobe: Fix NULL pointer dereference in fprobe_fgraph_entry()
tracing/probes: Fix double addition of offset for @+FOFFSET
tracing: eprobe: read the complete FILTER_PTR_STRING pointer
tracing/events: Fix to check the simple_tsk_fn creation
tracing/probes: Remove WARN_ON_ONCE from parse_btf_arg
tracing: probes: fix typo in a log message
ksmbd_close_fd_app_instance_id() looks up a prior durable handle by
AppInstanceId and closes it through opinfo->sess->file_table. This is
unsafe after the original session has been torn down. session_fd_check()
preserves reconnectable durable handles in the global table and clears
opinfo->conn/fp->conn, but opinfo->sess can still point to the freed
ksmbd_session.
Use opinfo->conn as the orphan sentinel, but make the check reliable by
serializing it with session_fd_check(). That path clears opinfo->conn
under fp->f_ci->m_lock, so hold the same lock while testing opinfo->conn
and while dereferencing opinfo->sess->file_table. Also avoid closing
through the session file table if the volatile id has already been
unpublished by session teardown.
Durable reconnect must keep the two fields consistent. Rebinding only
opinfo->conn leaves opinfo->sess pointing at the old freed session, so
a later app-instance supersede can pass the conn check and write-lock the
freed session's file table. Clear opinfo->sess when preserving a durable
handle during session teardown, and set it to the reconnecting session
when opinfo->conn is rebound in ksmbd_reopen_durable_fd().
Fixes: 16c3064970 ("ksmbd: handle durable v2 app instance id")
Reported-by: Gil Portnoy <dddhkts1@gmail.com>
Co-developed-by: Gil Portnoy <dddhkts1@gmail.com>
Signed-off-by: Gil Portnoy <dddhkts1@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb_grant_oplock() checks the previous oplock holder's o_fp to decide
whether a durable handle should be invalidated when the oplock break
cannot be delivered. prev_opinfo is obtained with opinfo_get_list(),
which pins only the oplock_info. It does not pin the ksmbd_file stored
in opinfo->o_fp.
A concurrent last close can unlink the opinfo from ci->m_op_list under
ci->m_lock and then free the ksmbd_file. The oplock_info can still be
kept alive by the refcount taken by opinfo_get_list(), but o_fp may
already point at freed memory by the time smb_grant_oplock() reads
is_durable, conn, or tcon.
Snapshot the previous holder's durable state while ci->m_lock is held,
then use only the copied values after dropping the lock. This keeps the
o_fp lifetime tied to the inode lock without taking an extra ksmbd_file
reference. Taking such a reference is unsafe here because smb_grant_oplock()
does not necessarily have the previous holder's session work, and dropping
the temporary reference can otherwise become the final putter.
Fixes: 26fa88dc87 ("ksmbd: invalidate durable handles on oplock break")
Reported-by: Gil Portnoy <dddhkts1@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
ksmbd_close_disconnected_durable_delete_on_close() collects disconnected
durable handles for a name being superseded by a new delete-on-close
open, drops ci->m_lock, then closes each collected handle directly with
__ksmbd_close_fd().
That bypasses the FP_CLOSED and refcount handoff used by the other close
paths. If a durable reconnect or the durable scavenger already took a
reference to the same fp, the direct __ksmbd_close_fd() can free the
ksmbd_file while that other holder still owns a live reference.
Claim the disconnected durable handle before unlinking it from m_fp_list.
While holding ci->m_lock and global_ft.lock, only take ownership when the
durable lifetime reference is the only remaining reference. Then take a
transient reference, remove the fp from global_ft, mark it FP_CLOSED, and
move it to the local dispose list. If another holder already has a
reference, leave the fp linked and let that holder complete its path.
The dispose loop then drops both references owned by the claim. This keeps
the force-close path in the same refcount handoff model as the durable
scavenger and avoids leaving a live reconnected fp detached from
m_fp_list.
Fixes: 166e4c0702 ("ksmbd: supersede disconnected delete-on-close durable handle")
Signed-off-by: Gil Portnoy <dddhkts1@gmail.com>
Co-developed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Two concurrent SMB2 durable reconnects (DH2C/DHnC) on the same
persistent_id race the fp->owner.name compare-read in
ksmbd_vfs_compare_durable_owner() against the kfree() in
ksmbd_reopen_durable_fd()'s reopen-success path. fp->owner.name is a
standalone kstrdup() buffer whose lifetime is independent of the fp
refcount, and the two sites share no lock: the compare reads the buffer
while the reopen frees it, so the strcmp() can dereference freed memory.
Commit 7ce4fc4001 ("ksmbd: fix durable reconnect double-bind race in
ksmbd_reopen_durable_fd") made the fp->conn claim atomic under
global_ft.lock (closing the owner.name double-free and the ksmbd_file
write-UAF), but the compare-read versus reopen-free pair was left
unserialized.
BUG: KASAN: slab-use-after-free in strcmp+0x2c/0x80
Read of size 1 by task kworker
strcmp
ksmbd_vfs_compare_durable_owner
smb2_check_durable_oplock
smb2_open
Freed by task kworker:
kfree
ksmbd_reopen_durable_fd
smb2_open
Allocated by task kworker:
kstrdup
session_fd_check
smb2_session_logoff
The buggy address belongs to the cache kmalloc-8
Serialize both sides of the race with fp->f_lock. The global durable
file-table lock still protects the durable reconnect claim, but
fp->owner.name is per-open state and does not need to block unrelated
durable table lookups or reconnects. The teardown is left at its
existing location after the reopen-success point so that an __open_id()
rollback still retains owner.name for a later legitimate reconnect to
verify.
Fixes: 49110a8ce6 ("ksmbd: validate owner of durable handle on reconnect")
Assisted-by: Henry (Claude):claude-opus-4
Signed-off-by: Gil Portnoy <dddhkts1@gmail.com>
Co-developed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
When a cifs.ko client caches a read-handle (RH) lease via deferred close
and a conflicting open arrives, ksmbd breaks the lease and waits for the
acknowledgment in wait_for_break_ack() for up to OPLOCK_WAIT_TIME (35s).
__smb_break_all_levII_oplock() runs that wait while holding ci->m_lock
for read.
cifs.ko reacts to a handle-lease break by closing the deferred handle
rather than sending a lease break acknowledgment. That close path
(close_id_del_oplock() -> opinfo_del()) takes ci->m_lock for write and
is exactly what would wake the waiter, but it blocks on the read lock
held by the waiting thread. The break is then resolved only by the 35s
timeout, so xfstests generic/001 takes ~78s with leases enabled versus
~4s with oplocks only.
Collect the target opinfos (each pinned with a reference) while holding
ci->m_lock, then break them after releasing it, matching how
smb_grant_oplock() already breaks a conflicting lease using only a
reference. The reference keeps the opinfo (and its conn and lease)
alive across the unlocked window, and a close racing the break is
handled by the existing OPLOCK_CLOSING state check. Apply the same fix
to the parent lease break paths.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Update ksmbd.rst to reflect the current implementation status of SMB
features. Durable handles (v1, v2) and SMB3.1.1 Compression are now
fully supported in ksmbd, so update their status from "Planned for future"
to "Supported".
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
session_fd_check() and ksmbd_reopen_durable_fd() walk ci->m_op_list with
list_for_each_entry_rcu() while holding ci->m_lock for write. That is
the local inode/oplock serializer, but the RCU-list iterator does not
currently tell lockdep about it.
Pass lockdep_is_held(&ci->m_lock) to these iterators so
CONFIG_PROVE_RCU_LIST can see the rwsem protection already in place.
This was found by our static analysis tool and then manually reviewed
against the current tree. The dynamic triage evidence is a
target-matched CONFIG_PROVE_RCU_LIST warning; the change is limited
to documenting the existing protection contract.
This is a lockdep annotation cleanup. It does not change oplock list
lifetime or durable-handle behavior.
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb2_validate_credit_charge() adds the request's CreditCharge to
conn->outstanding_credits when an SMB2 PDU is received, and
smb2_set_rsp_credits() subtracts it again when the response is built.
However smb2_set_rsp_credits() only runs on the normal response path:
- __process_request() returning SERVER_HANDLER_ABORT (unimplemented
command, command index out of range, signature check failure, or a
handler that sets send_no_response such as a cancelled blocking
lock) breaks out of the processing loop before set_rsp_credits() is
called;
- smb2_set_rsp_credits() itself returns early with -EINVAL (total
credit overflow or insufficient credits) before the subtraction.
On all of these paths the charge added at receive time is never
returned, so conn->outstanding_credits only grows. Because a client can
repeatedly trigger them (e.g. by sending unimplemented commands or by
issuing and cancelling blocking locks), outstanding_credits eventually
reaches total_credits and smb2_validate_credit_charge() then rejects
every subsequent request, wedging the connection.
Record the charge that was added in work->credit_charge and release any
charge still pending at the single send. exit point of
__handle_ksmbd_work(), which all abort and error paths fall through to.
smb2_set_rsp_credits() clears work->credit_charge once it has returned
the charge so the response path is unchanged and the credit is never
released twice. Paths that never charged a credit (no multi-credit
support, validation failure) leave work->credit_charge at zero and are
unaffected.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb2_validate_credit_charge() computes the credit charge a request is
allowed to consume from the payload size:
CreditCharge = (max(SendPayloadSize, ResponsePayloadSize) - 1)/65536 + 1
For SMB2 QUERY_INFO, the server must validate CreditCharge based on the
*maximum* of InputBufferLength and OutputBufferLength. ksmbd instead
summed the two lengths, which overestimates the required charge.
As a result a single-credit QUERY_INFO whose InputBufferLength and
OutputBufferLength each fit in 64KB but whose sum exceeds 64KB is
rejected with STATUS_INVALID_PARAMETER, even though it is a valid
request. IOCTL already uses max() of the request and response sizes;
make QUERY_INFO consistent by feeding InputBufferLength as the request
length and OutputBufferLength as the expected response length so that
smb2_validate_credit_charge() takes their maximum.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb2_read() allocates the read payload buffer with kvzalloc(), zeroing up
to max_read_size bytes (1MB or more with multichannel) on every read,
only to immediately overwrite the region with file data via kernel_read().
The zero-fill is pure overhead: ksmbd_vfs_read() returns the number of
bytes actually read ('nbytes'), and only those nbytes are ever consumed -
they are pinned into the response iov (ksmbd_iov_pin_rsp_read()), sent
over the RDMA channel (smb2_read_rdma_channel()), or copied by the
compression path (ksmbd_compress_response() uses iov_len == nbytes). The
ALIGN(length, 8) tail padding and any short-read remainder are never read
or transmitted, so they need not be initialized.
Use kvmalloc() instead to skip the redundant zeroing. This reduces CPU
and memory-bandwidth usage on large sequential reads.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
set_ntacl_dacl() copies each ACE from the attacker-controlled stored
security descriptor verbatim into the response DACL without checking
sid.num_subauth. The ACE bytes (including an unchecked num_subauth)
originate from an authenticated SMB2_SET_INFO(SecInfo=DACL) that is
stored raw via ksmbd_vfs_set_sd_xattr(); parse_dacl() rejects a bad ACE
with `break` rather than an error, so parse_sec_desc() still returns
success and the malformed SD reaches the xattr intact.
On a subsequent SMB2_QUERY_INFO(SecInfo=DACL) for an inode carrying a
POSIX access ACL, build_sec_desc() -> set_ntacl_dacl() ->
set_posix_acl_entries_dacl() walks the copied ACEs and reads
ntace->sid.sub_auth[ntace->sid.num_subauth - 1]
with num_subauth taken straight from the stored SD. Since sub_auth[]
is fixed at SID_MAX_SUB_AUTHORITIES (15), a crafted num_subauth (e.g.
255) drives an out-of-bounds heap read of ~1 KB with an offset fully
controlled by an authenticated client.
The sibling functions already gate this field:
parse_dacl() -- num_subauth == 0 || > SID_MAX_SUB_AUTHORITIES
parse_sid() -- num_subauth > SID_MAX_SUB_AUTHORITIES
smb_copy_sid() -- min_t(u8, num_subauth, SID_MAX_SUB_AUTHORITIES)
set_ntacl_dacl() is the lone inconsistent path that omits the check.
Add the same num_subauth validation in set_ntacl_dacl() before copying
the ACE, matching the gate already enforced by parse_dacl().
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Suggested-by: Namjae Jeon <linkinjeon@kernel.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
parse_dacl() limits the attacker-controlled ACE count by comparing it
with the number of minimal ACEs that fit in the DACL size. The DACL size
field is 16 bits, but the expression subtracts sizeof(struct smb_acl).
Because sizeof() is unsigned, a DACL size smaller than the ACL header
underflows to a large size_t.
A malicious client can reach this with:
SMB2_SET_INFO (InfoType=SMB2_O_INFO_SECURITY)
-> smb2_set_info_sec()
-> set_info_sec()
-> parse_sec_desc()
-> parse_dacl()
-> init_acl_state(..., 0xffff)
-> init_acl_state(..., 0xffff)
-> kmalloc_objs(..., 0xffff)
Thus a malformed security descriptor can make num_aces pass the guard
and drive large temporary ACL state and pointer-array allocations.
Reject DACLs smaller than struct smb_acl before doing the subtraction,
so the ACE count check cannot be bypassed by the underflow.
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Free ndr buffer data when ndr_encode_dos_attr() returns error
to avoid memory leak.
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
1. When ndr_decode_v4_ntacl() fails, the code jumped to free_n_data
which only freed n.data, skipping kfree(acl.sd_buf) and leaking
the buffer. Zero-initialize struct xattr_ntacl acl, reorder error
labels to out_free to release acl.sd_buf on all error paths.
2. if (acl.sd_size < sizeof(struct smb_ntsd)) is true, original code
returned success without freeing sd_buf and left stale *pntsd.
Set rc = -EINVAL before jumping to out_free to return error code and
free buffer.
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
ndr_encode_v4_ntacl() allocates sd_ndr.data via kzalloc() at entry.
If any subsequent ndr_write_*() call returns error during encoding,
the allocated sd_ndr.data won't be freed and causes memory leak.
Move kfree(sd_ndr.data) into out label to ensure the buffer gets
released on all success and error return paths.
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
tcf_bpf_act() can run from the tc egress path, which holds only
rcu_read_lock_bh(), but reads prog->filter with rcu_dereference() and
trips lockdep:
WARNING: suspicious RCU usage
net/sched/act_bpf.c:47 suspicious rcu_dereference_check() usage!
1 lock held by syz.2.1588/12756:
#0: (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit net/core/dev.c:4792
tcf_bpf_act+0x6ae/0x940 net/sched/act_bpf.c:47
tcf_classify+0x6e4/0x1080 net/sched/cls_api.c:1860
sch_handle_egress net/core/dev.c:4545 [inline]
__dev_queue_xmit+0x2185/0x2c00 net/core/dev.c:4808
packet_sendmsg+0x3dfa/0x5120 net/packet/af_packet.c:3114
The other tc actions and cls_bpf already use rcu_dereference_bh() here.
Do the same.
Fixes: 1f211a1b92 ("net, sched: add clsact qdisc")
Signed-off-by: Sechang Lim <rhkrqnwk98@gmail.com>
Reviewed-by: Amery Hung <ameryhung@gmail.com>
Link: https://patch.msgid.link/20260629154112.1164986-1-rhkrqnwk98@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The Kconfig entry for the al3320a is missing a `select REGMAP_I2C`,
causing build failures.
Fixes: 1850e6ae7f ("iio: light: al3320a: Implement regmap support")
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: David Heidelberg <david@ixit.cz>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The KConfig entry for the AL3010 is missing a `select REGMAP_I2C`,
causing build failures.
Fixes: 0e5e21e23d ("iio: light: al3010: Implement regmap support")
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: David Heidelberg <david@ixit.cz>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The KConfig entry for the al3000a is missing a `select REGMAP_I2C`,
causing build failures.
Fixes: d531b9f789 ("iio: light: Add support for AL3000a illuminance sensor")
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: David Heidelberg <david@ixit.cz>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
selinux_genfs_get_sid() allocates memory for a path with __get_free_page().
Such usage does not require a "page" and the size of the buffer should
actually be PATH_MAX which may be less than PAGE_SIZE on some
architectures.
Replace __get_free_page() for allocation of a path buffer with kmalloc()
and make it explicit that the buffer size is PATH_MAX.
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Reading a word from the stack in a kretprobe crashes a risc-v kernel.
$ cd /sys/kernel/tracing/
$ echo 'r n_tty_write $stack0' > dynamic_events
$ echo 1 > events/kprobes/enable
Unable to handle kernel paging request at virtual address 0000000200000128
...
[<ffffffff80016d16>] regs_get_kernel_stack_nth+0x26/0x38
[<ffffffff80177196>] process_fetch_insn+0x3ee/0x760
[<ffffffff80177836>] kretprobe_trace_func+0x116/0x1f0
[<ffffffff8017795a>] kretprobe_dispatcher+0x4a/0x58
[<ffffffff8013572e>] kretprobe_rethook_handler+0x5e/0x90
[<ffffffff80180838>] rethook_trampoline_handler+0x70/0x108
[<ffffffff8001ba32>] arch_rethook_trampoline_callback+0x12/0x1c
[<ffffffff8001ba84>] arch_rethook_trampoline+0x48/0x94
[<ffffffff8067872a>] tty_write+0x1a/0x30
In regs_get_kernel_stack_nth, regs->sp contains an arbitrary value.
arch_rethook_trampoline saves the registers from the probed function in a
struct pt_regs. sp is not saved. Instead, sp is decremented for
arch_rethook_trampoline's local stack.
Fix this crash and save the original sp along with the other registers.
Use a0 as a temporary register, it is overwritten anyway.
Cc: stable@vger.kernel.org
Fixes: c22b0bcb1d ("riscv: Add kprobes supported")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://patch.msgid.link/20260630194010.1824039-1-martin@kaiser.cx
[pjw@kernel.org: added Fixes tag; cc'ed stable]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
query_nic_features() detects which offloads depend on tx-gso-partial
by enabling everything, turning tx-gso-partial off, and seeing which
active features drop out. Enabling all hw features is dangerous:
we may end up enabling rx-fcs and loopback for example. For the
ice driver we end up getting into problems with feature dependencies
so the cleanup isn't successful either, and the test exits with
rx-fcs and loopback enabled.
Scope the feature probing just to segmentation bits.
Fixes: 266b835e5e ("selftests: drv-net: tso: enable test cases based on hw_features")
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20260629233923.2151144-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Depending on the value of chip_version, the correct decode set is selected.
However, the subsequent matching with the t4 encoding type in the if-else
block results in a reassignment, which leads to the loss of support for
t6_decode as well as reinitializing of values t4_decode and t5_decode.
The component history shows that the if-else block previously used for
this purpose, as well as the execution order, was not affected by the
change.
Furthermore, it is suggested by the execution order that the scenario with
overwriting and loss of support will be implemented.
Delete the if-else block.
Fixes: 6df397539c ("cxgb4: Update correct encoding of SGE Ingress DMA States for T6 adapter")
Signed-off-by: Gleb Markov <markov.gi@npc-ksb.ru>
Reviewed-by: Potnuri Bharat Teja <bharat@chelsio.com>
Link: https://patch.msgid.link/20260629130856.1168-1-markov.gi@npc-ksb.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Adjust the indentation and use tabs between function parameters and
their descriptions to align with the convention used in FPU code.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20250620052152.490414-1-chao.gao@intel.com
Breno Leitao says:
====================
net: do not warn on best-effort skb allocation failures
Both netconsole and netpoll keep a small preallocated pool of skbs
(skb_pool) so they can still get a buffer under memory pressure.
On the hot path they first attempt a normal GFP_ATOMIC allocation and only
fall back to the pool when that fails, keeping the pool as a last resort.
This is where the problem happens. If alloc_skb() fails, we now have
more than 100 message coming from the page=0 failure, which consumes
the scarce pool of skb, making the real issue disappear.
So the noise (memory allocation failure) deplets the SKB buffer and
crowds out the real message we were trying to deliver.
This is happening on the Meta fleet. The stack trace looks like:
pr/netcon_ext0: page allocation failure: order:0, mode:0x40820(GFP_ATOMIC|__GFP_COMP), nodemask=(null),cpuset=/,mems_allowed=0
...
dump_stack_lvl
warn_alloc
__alloc_pages_slowpath
__alloc_frozen_pages_noprof
alloc_pages_mpol
alloc_slab_page
allocate_slab
kmem_cache_alloc_node_noprof
__alloc_skb
send_udp
netconsole_write
nbcon_emit_next_record
nbcon_emit_one
nbcon_kthread_func
kthread
Solution: Do not warn if netconsole/netpoll fails to allocate these SKBs.
Pass __GFP_NOWARN on these best-effort allocations -- both the hot-path
attempt in netconsole's find_skb() and the pool refill in netpoll's
refill_skbs() -- and let the existing fallback paths do their job
quietly. The allocation will happen on SKB refill workqueue.
Given I am touching this code, if alloc_skb() fails, reschedule the
workqueue to try later.
====================
Link: https://patch.msgid.link/20260629-netpoll_no_warn-v1-0-f380f0b2cd0c@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
