Linux kernel
============
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several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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The allocation of a cell's anonymous key is done in a background thread
along with other cell setup such as doing a DNS upcall. In the reported
bug, this is triggered by afs_parse_source() parsing the device name given
to mount() and calling afs_lookup_cell() with the name of the cell.
The normal key lookup then tries to use the key description on the
anonymous authentication key as the reference for request_key() - but it
may not yet be set and so an oops can happen.
This has been made more likely to happen by the fix for dynamic lookup
failure.
Fix this by firstly allocating a reference name and attaching it to the
afs_cell record when the record is created. It can share the memory
allocation with the cell name (unfortunately it can't just overlap the cell
name by prepending it with "afs@" as the cell name already has a '.'
prepended for other purposes). This reference name is then passed to
request_key().
Secondly, the anon key is now allocated on demand at the point a key is
requested in afs_request_key() if it is not already allocated. A mutex is
used to prevent multiple allocation for a cell.
Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't
yet allocated (if we need it) and then the caller can return -ECHILD to
drop out of RCU-mode and afs_request_key() can be called.
Note that the anonymous key is kind of necessary to make the key lookup
cache work as that doesn't currently cache a negative lookup, but it's
probably worth some investigation to see if NULL can be used instead.
Fixes: 330e2c514823 ("afs: Fix dynamic lookup to fail on cell lookup failure")
Reported-by: syzbot+41c68824eefb67cdf00c@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/800328.1764325145@warthog.procyon.org.uk
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
As well as checking that the parent hasn't changed after getting the
lock we need to check that the dentry hasn't been unhashed.
Otherwise we might try to rename something that has been removed.
Reported-by: syzbot+bfc9a0ccf0de47d04e8c@syzkaller.appspotmail.com
Fixes: d2c995581c7c ("ovl: Call ovl_create_temp() without lock held.")
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/176429295510.634289.1552337113663461690@noble.neil.brown.name
Tested-by: syzbot+bfc9a0ccf0de47d04e8c@syzkaller.appspotmail.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
lookup_mnt_ns() already takes a reference on mnt_ns.
grab_requested_mnt_ns() doesn't need to take an extra reference.
Fixes: 78f0e33cd6c93 ("fs/namespace: correctly handle errors returned by grab_requested_mnt_ns")
Signed-off-by: Andrei Vagin <avagin@google.com>
Link: https://patch.msgid.link/20251122071953.3053755-1-avagin@google.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull clk fixes from Stephen Boyd:
"Fixes for the Allwinner A523 clk driver:
- Lower the minimum rate for the A523 audio PLL to support
frequencies required by audio devices
- Mark a couple clks critical on A523 so that Linux doesn't turn them
off when they're used by other code like TF-A"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: sunxi-ng: sun55i-a523-ccu: Lower audio0 pll minimum rate
clk: sunxi-ng: sun55i-a523-r-ccu: Mark bus-r-dma as critical
clk: sunxi-ng: Mark A523 bus-r-cpucfg clock as critical
Pull timer fixes from Ingo Molnar:
- Fix a race in timer->function clearing in timer_shutdown_sync()
- Fix a timekeeper sysfs-setup resource leak in error paths
- Fix the NOHZ report_idle_softirq() syslog rate-limiting
logic to have no side effects on the return value
* tag 'timers-urgent-2025-11-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Fix NULL function pointer race in timer_shutdown_sync()
timekeeping: Fix resource leak in tk_aux_sysfs_init() error paths
tick/sched: Fix bogus condition in report_idle_softirq()
Pull Allwinner clk driver fixes from Chen-Yu Tsai:
Just a couple fixes for the A523 family. A couple clocks are marked as
critical, and the lower bound of the audio PLL was lowered to match
the datasheet.
* tag 'sunxi-clk-fixes-for-6.18' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
clk: sunxi-ng: sun55i-a523-ccu: Lower audio0 pll minimum rate
clk: sunxi-ng: sun55i-a523-r-ccu: Mark bus-r-dma as critical
clk: sunxi-ng: Mark A523 bus-r-cpucfg clock as critical
Pull perf fixes from Ingo Molnar:
"Fix perf CPU-clock counters, and address a static checker warning"
* tag 'perf-urgent-2025-11-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix 0 count issue of cpu-clock
perf/x86/intel/uncore: Remove superfluous check
There is a race condition between timer_shutdown_sync() and timer
expiration that can lead to hitting a WARN_ON in expire_timers().
The issue occurs when timer_shutdown_sync() clears the timer function
to NULL while the timer is still running on another CPU. The race
scenario looks like this:
CPU0 CPU1
<SOFTIRQ>
lock_timer_base()
expire_timers()
base->running_timer = timer;
unlock_timer_base()
[call_timer_fn enter]
mod_timer()
...
timer_shutdown_sync()
lock_timer_base()
// For now, will not detach the timer but only clear its function to NULL
if (base->running_timer != timer)
ret = detach_if_pending(timer, base, true);
if (shutdown)
timer->function = NULL;
unlock_timer_base()
[call_timer_fn exit]
lock_timer_base()
base->running_timer = NULL;
unlock_timer_base()
...
// Now timer is pending while its function set to NULL.
// next timer trigger
<SOFTIRQ>
expire_timers()
WARN_ON_ONCE(!fn) // hit
...
lock_timer_base()
// Now timer will detach
if (base->running_timer != timer)
ret = detach_if_pending(timer, base, true);
if (shutdown)
timer->function = NULL;
unlock_timer_base()
The problem is that timer_shutdown_sync() clears the timer function
regardless of whether the timer is currently running. This can leave a
pending timer with a NULL function pointer, which triggers the
WARN_ON_ONCE(!fn) check in expire_timers().
Fix this by only clearing the timer function when actually detaching the
timer. If the timer is running, leave the function pointer intact, which is
safe because the timer will be properly detached when it finishes running.
Fixes: 0cc04e80458a ("timers: Add shutdown mechanism to the internal functions")
Signed-off-by: Yipeng Zou <zouyipeng@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20251122093942.301559-1-zouyipeng@huawei.com
While the user manual states that the PLL's rate should be between 180
MHz and 3 GHz in the register defninition section, it also says the
actual operating frequency is 22.5792*4 MHz in the PLL features table.
22.5792*4 MHz is one of the actual clock rates that we want and is
is available in the SDM table. Lower the minimum clock rate to 90 MHz
so that both rates in the SDM table can be used.
Fixes: 7cae1e2b5544 ("clk: sunxi-ng: Add support for the A523/T527 CCU PLLs")
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20251020171059.2786070-7-wens@kernel.org
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>
Pull MIPS fixes from Thomas Bogendoerfer:
- Fix CPU type in DT for econet
- Fix for Malta PCI MMIO breakage for SOC-it
- Fix TLB shutdown caused by iniital uniquification
- Fix random seg faults due to missed vdso storage requirement
* tag 'mips-fixes_6.18_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: kernel: Fix random segmentation faults
MIPS: mm: Prevent a TLB shutdown on initial uniquification
mips: dts: econet: fix EN751221 core type
MIPS: Malta: Fix !EVA SOC-it PCI MMIO
Currently cpu-clock event always returns 0 count, e.g.,
perf stat -e cpu-clock -- sleep 1
Performance counter stats for 'sleep 1':
0 cpu-clock # 0.000 CPUs utilized
1.002308394 seconds time elapsed
The root cause is the commit 'bc4394e5e79c ("perf: Fix the throttle
error of some clock events")' adds PERF_EF_UPDATE flag check before
calling cpu_clock_event_update() to update the count, however the
PERF_EF_UPDATE flag is never set when the cpu-clock event is stopped in
counting mode (pmu->dev() -> cpu_clock_event_del() ->
cpu_clock_event_stop()). This leads to the cpu-clock event count is
never updated.
To fix this issue, force to set PERF_EF_UPDATE flag for cpu-clock event
just like what task-clock does.
Fixes: bc4394e5e79c ("perf: Fix the throttle error of some clock events")
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://patch.msgid.link/20251112080526.3971392-1-dapeng1.mi@linux.intel.com
tk_aux_sysfs_init() returns immediately on error during the auxiliary clock
initialization loop without cleaning up previously allocated kobjects and
sysfs groups.
If kobject_create_and_add() or sysfs_create_group() fails during loop
iteration, the parent kobjects (tko and auxo) and any previously created
child kobjects are leaked.
Fix this by adding proper error handling with goto labels to ensure all
allocated resources are cleaned up on failure. kobject_put() on the
parent kobjects will handle cleanup of their children.
Fixes: 7b95663a3d96 ("timekeeping: Provide interface to control auxiliary clocks")
Signed-off-by: Malaya Kumar Rout <mrout@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251120150213.246777-1-mrout@redhat.com
Pull i2c fix from Wolfram Sang:
"One revert because of a regression in the I2C core which has sadly not
showed up during its time in -next"
* tag 'i2c-for-6.18-rc1-hotfix' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
Revert "i2c: boardinfo: Annotate code used in init phase only"
The "bus-r-dma" clock in the A523's PRCM clock controller is also
referred to as "DMA_CLKEN_SW" or "DMA ADB400 gating". It is unclear how
this ties into the DMA controller MBUS clock gate; however if the clock
is not enabled, the DMA controller in the MCU block will fail to access
DRAM, even failing to retrieve the DMA descriptors.
Mark this clock as critical. This sort of mirrors what is done for the
main DMA controller's MBUS clock, which has a separate toggle that is
currently left out of the main clock controller driver.
Fixes: 8cea339cfb81 ("clk: sunxi-ng: add support for the A523/T527 PRCM CCU")
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20251020171059.2786070-6-wens@kernel.org
Signed-off-by: Chen-Yu Tsai <wens@kernel.org>
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