tjh.dev
Linux kernel
============
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requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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When creating sysfs files fail, the allocated minor must be freed such that
it can be later reused. That is specially harmful for static minor numbers,
since those would always fail to register later on.
Fixes: 6d04d2b554b1 ("misc: misc_minor_alloc to use ida for all dynamic/misc dynamic minors")
Cc: stable <stable@kernel.org>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Link: https://lore.kernel.org/r/20250123123249.4081674-5-cascardo@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dev_id value in the GPIO lookup table must match to
the device instance name, which in this case is combined
of name and platform device ID, i.e. "spi_gpio.1". But
the table assumed that there was no platform device ID
defined, which is wrong. Fix the dev_id value accordingly.
Fixes: 9b00bc7b901f ("spi: spi-gpio: Rewrite to use GPIO descriptors")
Cc: stable <stable@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250206220311.1554075-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the "pmcmd_ioctl" function, three memory objects allocated by
kmalloc are initialized by "hcall_get_cpu_state", which are then
copied to user space. The initializer is indeed implemented in
"acrn_hypercall2" (arch/x86/include/asm/acrn.h). There is a risk of
information leakage due to uninitialized bytes.
Fixes: 3d679d5aec64 ("virt: acrn: Introduce interfaces to query C-states and P-states allowed by hypervisor")
Signed-off-by: Haoyu Li <lihaoyu499@gmail.com>
Cc: stable <stable@kernel.org>
Acked-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20250130115811.92424-1-lihaoyu499@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Devices created through binderfs are added to the global binder_devices
list but are not removed before being destroyed. This leads to dangling
pointers in the list and subsequent use-after-free errors:
==================================================================
BUG: KASAN: slab-use-after-free in binder_add_device+0x5c/0x9c
Write of size 8 at addr ffff0000c258d708 by task mount/653
CPU: 7 UID: 0 PID: 653 Comm: mount Not tainted 6.13.0-09030-g6d61a53dd6f5 #1
Hardware name: linux,dummy-virt (DT)
Call trace:
binder_add_device+0x5c/0x9c
binderfs_binder_device_create+0x690/0x84c
[...]
__arm64_sys_mount+0x324/0x3bc
Allocated by task 632:
binderfs_binder_device_create+0x168/0x84c
binder_ctl_ioctl+0xfc/0x184
[...]
__arm64_sys_ioctl+0x110/0x150
Freed by task 649:
kfree+0xe0/0x338
binderfs_evict_inode+0x138/0x1dc
[...]
==================================================================
Remove devices from binder_devices before destroying them.
Cc: Li Li <dualli@google.com>
Reported-by: syzbot+7015dcf45953112c8b45@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7015dcf45953112c8b45
Fixes: 12d909cac1e1 ("binderfs: add new binder devices to binder_devices")
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Tested-by: syzbot+7015dcf45953112c8b45@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20250130215823.1518990-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of interrupt delay for any reason, slim_do_transfer()
returns timeout error but the transaction ID (TID) is not freed.
This results into invalid memory access inside
qcom_slim_ngd_rx_msgq_cb() due to invalid TID.
Fix the issue by freeing the TID in slim_do_transfer() before
returning timeout error to avoid invalid memory access.
Call trace:
__memcpy_fromio+0x20/0x190
qcom_slim_ngd_rx_msgq_cb+0x130/0x290 [slim_qcom_ngd_ctrl]
vchan_complete+0x2a0/0x4a0
tasklet_action_common+0x274/0x700
tasklet_action+0x28/0x3c
_stext+0x188/0x620
run_ksoftirqd+0x34/0x74
smpboot_thread_fn+0x1d8/0x464
kthread+0x178/0x238
ret_from_fork+0x10/0x20
Code: aa0003e8 91000429 f100044a 3940002b (3800150b)
---[ end trace 0fe00bec2b975c99 ]---
Kernel panic - not syncing: Oops: Fatal exception in interrupt.
Fixes: afbdcc7c384b ("slimbus: Add messaging APIs to slimbus framework")
Cc: stable <stable@kernel.org>
Signed-off-by: Visweswara Tanuku <quic_vtanuku@quicinc.com>
Link: https://lore.kernel.org/r/20250124125740.16897-1-quic_vtanuku@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The vboxguest driver depends on port I/O for debug output:
include/asm-generic/io.h:626:15: error: call to '_outl' declared with attribute error: outl() requires CONFIG_HAS_IOPORT
626 | #define _outl _outl
include/asm-generic/io.h:663:14: note: in expansion of macro '_outl'
663 | #define outl _outl
| ^~~~~
drivers/virt/vboxguest/vboxguest_utils.c:102:9: note: in expansion of macro 'outl'
102 | outl(phys_req, gdev->io_port + VMMDEV_PORT_OFF_REQUEST);
| ^~~~
Most arm64 platforms don't actually support port I/O, though it is
currently enabled unconditionally. Refine the vbox dependency to allow
turning HAS_IOPORT off in the future when building for platforms without
port I/O and allow compile-testing on all architectures.
Fixes: 5cf8f938bf5c ("vbox: Enable VBOXGUEST and VBOXSF_FS on ARM64")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20250122065445.1469218-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixed a possible UAF problem in driver_override_show() in drivers/cdx/cdx.c
This function driver_override_show() is part of DEVICE_ATTR_RW, which
includes both driver_override_show() and driver_override_store().
These functions can be executed concurrently in sysfs.
The driver_override_store() function uses driver_set_override() to
update the driver_override value, and driver_set_override() internally
locks the device (device_lock(dev)). If driver_override_show() reads
cdx_dev->driver_override without locking, it could potentially access
a freed pointer if driver_override_store() frees the string
concurrently. This could lead to printing a kernel address, which is a
security risk since DEVICE_ATTR can be read by all users.
Additionally, a similar pattern is used in drivers/amba/bus.c, as well
as many other bus drivers, where device_lock() is taken in the show
function, and it has been working without issues.
This potential bug was detected by our experimental static analysis
tool, which analyzes locking APIs and paired functions to identify
data races and atomicity violations.
Fixes: 1f86a00c1159 ("bus/fsl-mc: add support for 'driver_override' in the mc-bus")
Cc: stable <stable@kernel.org>
Signed-off-by: Qiu-ji Chen <chenqiuji666@gmail.com>
Link: https://lore.kernel.org/r/20250118070833.27201-1-chenqiuji666@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for the Trace Hub in Panther Lake-P/U.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20250211185017.1759193-6-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for the Trace Hub in Panther Lake-H.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20250211185017.1759193-5-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for the Trace Hub in Arrow Lake.
Signed-off-by: Pawel Chmielewski <pawel.chmielewski@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20250211185017.1759193-4-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct function comments to prevent kernel-doc warnings found when using
"W=1" that the drive-by fixers had trouble documenting and skipped over.
msu.c:168: warning: Function parameter or struct member 'msu_base' not described in 'msc'
msu.c:168: warning: Function parameter or struct member 'work' not described in 'msc'
msu.c:168: warning: Function parameter or struct member 'switch_on_unlock' not described in 'msc'
msu.c:168: warning: Function parameter or struct member 'iter_list' not described in 'msc'
msu.c:168: warning: Function parameter or struct member 'stop_on_full' not described in 'msc'
msu.c:168: warning: Function parameter or struct member 'do_irq' not described in 'msc'
msu.c:168: warning: Function parameter or struct member 'multi_is_broken' not described in 'msc'
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250211185017.1759193-3-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct function comments to prevent kernel-doc warnings
found when using "W=1".
msu.c:162: warning: Function parameter or struct member 'mbuf_priv' not described in 'msc'
msu.c:164: warning: Function parameter or struct member 'orig_addr' not described in 'msc'
msu.c:164: warning: Function parameter or struct member 'orig_sz' not described in 'msc'
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20250211185017.1759193-2-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Manivannan writes:
MHI Host
========
- Use pci_try_reset_function() to reset the MHI function during recovery process
to avoid the deadlock reported on the X1E80100 CRD device. The deadlock can
happen if the caller has already acquired the 'device_lock()' while calling
the recovery function. So using pci_try_reset_function() avoids the deadlock
by returning -EAGAIN if the lock was already acquired.
* tag 'mhi-fixes-for-v6.14' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/mani/mhi:
bus: mhi: host: pci_generic: Use pci_try_reset_function() to avoid deadlock
Due to job transitions, both Joel and Jeremy can no longer maintain
the FSI subsystem. I will take over.
I also replaced Alistair with Ninad as a reviewer, as Alistair doesn't
have access to hardware and hasn't been active.
I also removed the link to Joel's FSI tree as he won't be maintaining
it.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Link: https://lore.kernel.org/r/20250213225746.2159118-1-eajames@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are multiple places from where the recovery work gets scheduled
asynchronously. Also, there are multiple places where the caller waits
synchronously for the recovery to be completed. One such place is during
the PM shutdown() callback.
If the device is not alive during recovery_work, it will try to reset the
device using pci_reset_function(). This function internally will take the
device_lock() first before resetting the device. By this time, if the lock
has already been acquired, then recovery_work will get stalled while
waiting for the lock. And if the lock was already acquired by the caller
which waits for the recovery_work to be completed, it will lead to
deadlock.
This is what happened on the X1E80100 CRD device when the device died
before shutdown() callback. Driver core calls the driver's shutdown()
callback while holding the device_lock() leading to deadlock.
And this deadlock scenario can occur on other paths as well, like during
the PM suspend() callback, where the driver core would hold the
device_lock() before calling driver's suspend() callback. And if the
recovery_work was already started, it could lead to deadlock. This is also
observed on the X1E80100 CRD.
So to fix both issues, use pci_try_reset_function() in recovery_work. This
function first checks for the availability of the device_lock() before
trying to reset the device. If the lock is available, it will acquire it
and reset the device. Otherwise, it will return -EAGAIN. If that happens,
recovery_work will fail with the error message "Recovery failed" as not
much could be done.
Cc: stable@vger.kernel.org # 5.12
Reported-by: Johan Hovold <johan@kernel.org>
Closes: https://lore.kernel.org/mhi/Z1me8iaK7cwgjL92@hovoldconsulting.com
Fixes: 7389337f0a78 ("mhi: pci_generic: Add suspend/resume/recovery procedure")
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Analyzed-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/mhi/Z2KKjWY2mPen6GPL@hovoldconsulting.com/
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/20250108-mhi_recovery_fix-v1-1-a0a00a17da46@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
This allows ntsync to be usuable by non-root processes out of the box
Signed-off-by: Mike Lothian <mike@fireburn.co.uk>
Reviewed-by: Elizabeth Figura <zfigura@codeweavers.com>
Link: https://lore.kernel.org/r/20250214122759.2629-2-mike@fireburn.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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