Linux kernel ============ The Linux kernel is the core of any Linux operating system. It manages hardware, system resources, and provides the fundamental services for all other software. Quick Start ----------- * Report a bug: See Documentation/admin-guide/reporting-issues.rst * Get the latest kernel: https://kernel.org * Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst * Join the community: https://lore.kernel.org/ Essential Documentation ----------------------- All users should be familiar with: * Building requirements: Documentation/process/changes.rst * Code of Conduct: Documentation/process/code-of-conduct.rst * License: See COPYING Documentation can be built with make htmldocs or viewed online at: https://www.kernel.org/doc/html/latest/ Who Are You? ============ Find your role below: * New Kernel Developer - Getting started with kernel development * Academic Researcher - Studying kernel internals and architecture * Security Expert - Hardening and vulnerability analysis * Backport/Maintenance Engineer - Maintaining stable kernels * System Administrator - Configuring and troubleshooting * Maintainer - Leading subsystems and reviewing patches * Hardware Vendor - Writing drivers for new hardware * Distribution Maintainer - Packaging kernels for distros For Specific Users ================== New Kernel Developer -------------------- Welcome! Start your kernel development journey here: * Getting Started: Documentation/process/development-process.rst * Your First Patch: Documentation/process/submitting-patches.rst * Coding Style: Documentation/process/coding-style.rst * Build System: Documentation/kbuild/index.rst * Development Tools: Documentation/dev-tools/index.rst * Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst * Core APIs: Documentation/core-api/index.rst Academic Researcher ------------------- Explore the kernel's architecture and internals: * Researcher Guidelines: Documentation/process/researcher-guidelines.rst * Memory Management: Documentation/mm/index.rst * Scheduler: Documentation/scheduler/index.rst * Networking Stack: Documentation/networking/index.rst * Filesystems: Documentation/filesystems/index.rst * RCU (Read-Copy Update): Documentation/RCU/index.rst * Locking Primitives: Documentation/locking/index.rst * Power Management: Documentation/power/index.rst Security Expert --------------- Security documentation and hardening guides: * Security Documentation: Documentation/security/index.rst * LSM Development: Documentation/security/lsm-development.rst * Self Protection: Documentation/security/self-protection.rst * Reporting Vulnerabilities: Documentation/process/security-bugs.rst * CVE Procedures: Documentation/process/cve.rst * Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst * Security Features: Documentation/userspace-api/seccomp_filter.rst Backport/Maintenance Engineer ----------------------------- Maintain and stabilize kernel versions: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * Backporting Guide: Documentation/process/backporting.rst * Applying Patches: Documentation/process/applying-patches.rst * Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git for Maintainers: Documentation/maintainer/configure-git.rst System Administrator -------------------- Configure, tune, and troubleshoot Linux systems: * Admin Guide: Documentation/admin-guide/index.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst * Tracing/Debugging: Documentation/trace/index.rst * Performance Security: Documentation/admin-guide/perf-security.rst * Hardware Monitoring: Documentation/hwmon/index.rst Maintainer ---------- Lead kernel subsystems and manage contributions: * Maintainer Handbook: Documentation/maintainer/index.rst * Pull Requests: Documentation/maintainer/pull-requests.rst * Managing Patches: Documentation/maintainer/modifying-patches.rst * Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst * Development Process: Documentation/process/maintainer-handbooks.rst * Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git Configuration: Documentation/maintainer/configure-git.rst Hardware Vendor --------------- Write drivers and support new hardware: * Driver API Guide: Documentation/driver-api/index.rst * Driver Model: Documentation/driver-api/driver-model/driver.rst * Device Drivers: Documentation/driver-api/infrastructure.rst * Bus Types: Documentation/driver-api/driver-model/bus.rst * Device Tree Bindings: Documentation/devicetree/bindings/ * Power Management: Documentation/driver-api/pm/index.rst * DMA API: Documentation/core-api/dma-api.rst Distribution Maintainer ----------------------- Package and distribute the kernel: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * ABI Documentation: Documentation/ABI/README * Kernel Configuration: Documentation/kbuild/kconfig.rst * Module Signing: Documentation/admin-guide/module-signing.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst Communication and Support ========================= * Mailing Lists: https://lore.kernel.org/ * IRC: #kernelnewbies on irc.oftc.net * Bugzilla: https://bugzilla.kernel.org/ * MAINTAINERS file: Lists subsystem maintainers and mailing lists * Email Clients: Documentation/process/email-clients.rst
Clone this repository
For self-hosted knots, clone URLs may differ based on your setup.
Download tar.gz
A recent change fixing a device reference leak in a UDC driver
introduced a potential use-after-free in the non-OF case as the
isp1301_get_client() helper only increases the reference count for the
returned I2C device in the OF case.
Increment the reference count also for non-OF so that the caller can
decrement it unconditionally.
Note that this is inherently racy just as using the returned I2C device
is since nothing is preventing the PHY driver from being unbound while
in use.
Fixes: c84117912bdd ("USB: lpc32xx_udc: Fix error handling in probe")
Cc: stable@vger.kernel.org
Cc: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Link: https://patch.msgid.link/20251218153519.19453-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A recent change fixing a device reference leak introduced a clock
imbalance by reusing an error path so that the clock may be disabled
before having been enabled.
Note that the clock framework allows for passing in NULL clocks so there
is no risk for a NULL pointer dereference.
Also drop the bogus I2C client NULL check added by the offending commit
as the pointer has already been verified to be non-NULL.
Fixes: c84117912bdd ("USB: lpc32xx_udc: Fix error handling in probe")
Cc: stable@vger.kernel.org
Cc: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Link: https://patch.msgid.link/20251218153519.19453-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Originally, the notification for connector change will be enabled after
the first read of the connector status. Therefore, if the event happens
during this window, it will be missing and make the status unsynced.
Get the connector status only after enabling the notification for
connector change to ensure the status is synced.
Fixes: c1b0bc2dabfa ("usb: typec: Add support for UCSI interface")
Cc: stable <stable@kernel.org>
Tested-by: Kenneth R. Crudup <kenny@panix.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hsin-Te Yuan <yuanhsinte@chromium.org>
Link: https://patch.msgid.link/20251218-ucsi-v7-1-aea83e83fb12@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We cannot determine which models require the NO_ATA_1X and
IGNORE_RESIDUE quirks aside from the EL-R12 optical drive device.
Fixes: 955a48a5353f ("usb: usb-storage: No additional quirks need to be added to the EL-R12 optical drive.")
Signed-off-by: Chen Changcheng <chenchangcheng@kylinos.cn>
Link: https://patch.msgid.link/20251218012318.15978-1-chenchangcheng@kylinos.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When clk_bulk_prepare_enable() fails, the error path jumps to
err_resetc_assert, skipping clk_bulk_put_all() and leaking the
clock references acquired by clk_bulk_get_all().
Add err_clk_put_all label to properly release clock resources
in all error paths.
Found via static analysis and code review.
Fixes: c0c61471ef86 ("usb: dwc3: of-simple: Convert to bulk clk API")
Cc: stable <stable@kernel.org>
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://patch.msgid.link/20251211064937.2360510-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add missing null check for cci parameter before dereferencing it in
ucsi_sync_control_common(). The function can be called with cci=NULL
from ucsi_acknowledge(), which leads to a null pointer dereference
when accessing *cci in the condition check.
The crash occurs because the code checks if cci is not null before
calling ucsi->ops->read_cci(ucsi, cci), but then immediately
dereferences cci without a null check in the following condition:
(*cci & UCSI_CCI_COMMAND_COMPLETE).
KASAN trace:
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:ucsi_sync_control_common+0x2ae/0x4e0 [typec_ucsi]
Cc: stable <stable@kernel.org>
Fixes: 667ecac55861 ("usb: typec: ucsi: return CCI and message from sync_control callback")
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Link: https://patch.msgid.link/20251216122210.5457-1-superm1@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lpc32xx_udc_probe() acquires an i2c_client reference through
isp1301_get_client() but fails to release it in both error handling
paths and the normal removal path. This could result in a reference
count leak for the I2C device, preventing proper cleanup and potentially
leading to resource exhaustion. Add put_device() to release the
reference in the probe failure path and in the remove function.
Calling path: isp1301_get_client() -> of_find_i2c_device_by_node() ->
i2c_find_device_by_fwnode(). As comments of i2c_find_device_by_fwnode()
says, 'The user must call put_device(&client->dev) once done with the
i2c client.'
Found by code review.
Cc: stable <stable@kernel.org>
Fixes: 24a28e428351 ("USB: gadget driver for LPC32xx")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Link: https://patch.msgid.link/20251215020931.15324-1-make24@iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In error paths, call typec_altmode_put_plug() to drop the device reference
obtained by typec_altmode_get_plug().
Fixes: 71ba4fe56656 ("usb: typec: altmodes/displayport: add SOP' support")
Cc: stable <stable@kernel.org>
Signed-off-by: Haoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20251206070445.190770-1-lihaoxiang@isrc.iscas.ac.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The delayed work item otg_event is initialized in fsl_otg_conf() and
scheduled under two conditions:
1. When a host controller binds to the OTG controller.
2. When the USB ID pin state changes (cable insertion/removal).
A race condition occurs when the device is removed via fsl_otg_remove():
the fsl_otg instance may be freed while the delayed work is still pending
or executing. This leads to use-after-free when the work function
fsl_otg_event() accesses the already freed memory.
The problematic scenario:
(detach thread) | (delayed work)
fsl_otg_remove() |
kfree(fsl_otg_dev) //FREE| fsl_otg_event()
| og = container_of(...) //USE
| og-> //USE
Fix this by calling disable_delayed_work_sync() in fsl_otg_remove()
before deallocating the fsl_otg structure. This ensures the delayed work
is properly canceled and completes execution prior to memory deallocation.
This bug was identified through static analysis.
Fixes: 0807c500a1a6 ("USB: add Freescale USB OTG Transceiver driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://patch.msgid.link/20251205034831.12846-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usbhsp_get_pipe() set pipe's flags to IS_USED. In error paths,
usbhsp_put_pipe() is required to clear pipe's flags to prevent
pipe exhaustion.
Fixes: f1407d5c6624 ("usb: renesas_usbhs: Add Renesas USBHS common code")
Cc: stable <stable@kernel.org>
Signed-off-by: Haoxiang Li <haoxiang_li2024@163.com>
Link: https://patch.msgid.link/20251204132129.109234-1-haoxiang_li2024@163.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Selecting DRM_AUX_HPD_BRIDGE is not possible from a built-in driver when
CONFIG_DRM=m:
WARNING: unmet direct dependencies detected for DRM_AUX_HPD_BRIDGE
Depends on [m]: HAS_IOMEM [=y] && DRM [=m] && DRM_BRIDGE [=y] && OF [=y]
Selected by [y]:
- UCSI_HUAWEI_GAOKUN [=y] && USB_SUPPORT [=y] && TYPEC [=y] && TYPEC_UCSI [=y] && EC_HUAWEI_GAOKUN [=y] && DRM_BRIDGE [=y] && OF [=y]
Add the same dependency we have in similar drivers to work around this.
Fixes: 00327d7f2c8c ("usb: typec: ucsi: add Huawei Matebook E Go ucsi driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://patch.msgid.link/20251204101111.1035975-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some platforms, switching USB roles from host to device can trigger
controller faults due to premature PHY power-down. This occurs when the
PHY is disabled too early during teardown, causing synchronization
issues between the PHY and controller.
Keep susphy enabled during dwc3_host_exit() and dwc3_gadget_exit()
ensures the PHY remains in a low-power state capable of handling
required commands during role switch.
Cc: stable <stable@kernel.org>
Fixes: 6d735722063a ("usb: dwc3: core: Prevent phy suspend during init")
Suggested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Udipto Goswami <udipto.goswami@oss.qualcomm.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://patch.msgid.link/20251126054221.120638-1-udipto.goswami@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixup replaces tty_vhangup() call with call to
tty_port_tty_vhangup(). Both calls hangup tty device
synchronously however tty_port_tty_vhangup() increases
reference count during the hangup operation using
scoped_guard(tty_port_tty).
Cc: stable <stable@kernel.org>
Fixes: 1f73b8b56cf3 ("xhci: dbgtty: fix device unregister")
Signed-off-by: Łukasz Bartosik <ukaszb@chromium.org>
Link: https://patch.msgid.link/20251127111644.3161386-1-ukaszb@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull SCSI fixes from James Bottomley:
"The only core fix is in doc; all the others are in drivers, with the
biggest impacts in libsas being the rollback on error handling and in
ufs coming from a couple of error handling fixes, one causing a crash
if it's activated before scanning and the other fixing W-LUN
resumption"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: qcom: Fix confusing cleanup.h syntax
scsi: libsas: Add rollback handling when an error occurs
scsi: device_handler: Return error pointer in scsi_dh_attached_handler_name()
scsi: ufs: core: Fix a deadlock in the frequency scaling code
scsi: ufs: core: Fix an error handler crash
scsi: Revert "scsi: libsas: Fix exp-attached device scan after probe failure scanned in again after probe failed"
scsi: ufs: core: Fix RPMB link error by reversing Kconfig dependencies
scsi: qla4xxx: Use time conversion macros
scsi: qla2xxx: Enable/disable IRQD_NO_BALANCING during reset
scsi: ipr: Enable/disable IRQD_NO_BALANCING during reset
scsi: imm: Fix use-after-free bug caused by unfinished delayed work
scsi: target: sbp: Remove KMSG_COMPONENT macro
scsi: core: Correct documentation for scsi_device_quiesce()
scsi: mpi3mr: Prevent duplicate SAS/SATA device entries in channel 1
scsi: target: Reset t_task_cdb pointer in error case
scsi: ufs: core: Fix EH failure after W-LUN resume error
Pull ceph updates from Ilya Dryomov:
"We have a patch that adds an initial set of tracepoints to the MDS
client from Max, a fix that hardens osdmap parsing code from myself
(marked for stable) and a few assorted fixups"
* tag 'ceph-for-6.19-rc1' of https://github.com/ceph/ceph-client:
rbd: stop selecting CRC32, CRYPTO, and CRYPTO_AES
ceph: stop selecting CRC32, CRYPTO, and CRYPTO_AES
libceph: make decode_pool() more resilient against corrupted osdmaps
libceph: Amend checking to fix `make W=1` build breakage
ceph: Amend checking to fix `make W=1` build breakage
ceph: add trace points to the MDS client
libceph: fix log output race condition in OSD client