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Cancelling an rx command is signalled using bit 14 of the rx DMA status
register and not bit 11.
This bit is currently unused, but this error becomes apparent, for
example, when tracing the status register when closing the port.
Fixes: eddac5af0654 ("soc: qcom: Add GENI based QUP Wrapper driver")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20241009145110.16847-7-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The receiver is supposed to be enabled in the startup() callback and not
in set_termios() which is called also during console setup.
This specifically avoids accepting input before the port has been opened
(and interrupts enabled), something which can also break the GENI
firmware (cancel fails and after abort, the "stale" counter handling
appears to be broken so that later input is not processed until twelve
chars have been received).
There also does not appear to be any need to keep the receiver disabled
while updating the port settings.
Since commit 6f3c3cafb115 ("serial: qcom-geni: disable interrupts during
console writes") the calls to manipulate the secondary interrupts, which
were done without holding the port lock, can also lead to the receiver
being left disabled when set_termios() races with the console code (e.g.
when init opens the tty during boot). This can manifest itself as a
serial getty not accepting input.
The calls to stop and start rx in set_termios() can similarly race with
DMA completion and, for example, cause the DMA buffer to be unmapped
twice or the mapping to be leaked.
Fix this by only enabling the receiver during startup and while holding
the port lock to avoid racing with the console code.
Fixes: 6f3c3cafb115 ("serial: qcom-geni: disable interrupts during console writes")
Fixes: 2aaa43c70778 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Cc: stable@vger.kernel.org # 6.3
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20241009145110.16847-6-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to wait for the DMA transfer to complete when cancelling the
rx command on stop_rx(). This specifically prevents the DMA completion
interrupt from firing after rx has been restarted, something which can
lead to an IOMMU fault and hosed rx when the interrupt handler unmaps
the DMA buffer for the new command:
qcom_geni_serial 988000.serial: serial engine reports 0 RX bytes in!
arm-smmu 15000000.iommu: FSR = 00000402 [Format=2 TF], SID=0x563
arm-smmu 15000000.iommu: FSYNR0 = 00210013 [S1CBNDX=33 WNR PLVL=3]
Bluetooth: hci0: command 0xfc00 tx timeout
Bluetooth: hci0: Reading QCA version information failed (-110)
Also add the missing state machine reset which is needed in case
cancellation fails.
Fixes: 2aaa43c70778 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Cc: stable@vger.kernel.org # 6.3
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20241009145110.16847-5-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A commit adding back the stopping of tx on port shutdown failed to add
back the locking which had also been removed by commit e83766334f96
("tty: serial: qcom_geni_serial: No need to stop tx/rx on UART
shutdown").
Holding the port lock is needed to serialise against the console code,
which may update the interrupt enable register and access the port
state.
Fixes: d8aca2f96813 ("tty: serial: qcom-geni-serial: stop operations in progress at shutdown")
Fixes: 947cc4ecc06c ("serial: qcom-geni: fix soft lockup on sw flow control and suspend")
Cc: stable@vger.kernel.org # 6.3
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20241009145110.16847-4-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 35781d8356a2eecaa6074ceeb80ee22e252fcdae.
Hibernation is not supported on Qualcomm platforms with mainline
kernels yet a broken vendor implementation for the GENI serial driver
made it upstream.
This is effectively dead code that cannot be tested and should just be
removed, but if these paths were ever hit for an open non-console port
they would crash the machine as the driver would fail to enable clocks
during restore() (i.e. all ports would have to be closed by drivers and
user space before hibernating the system to avoid this as a comment in
the code hinted at).
The broken implementation also added a random call to enable the
receiver in the port setup code where it does not belong and which
enables the receiver prematurely for console ports.
Fixes: 35781d8356a2 ("tty: serial: qcom-geni-serial: Add support for Hibernation feature")
Cc: stable@vger.kernel.org # 6.2
Cc: Aniket Randive <quic_arandive@quicinc.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20241009145110.16847-3-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The polled console (KGDB/KDB) implementation must not call port setup
unconditionally as the port may already be in use by the console or a
getty.
Only make sure that the receiver is enabled, but do not enable any
device interrupts.
Fixes: d8851a96ba25 ("tty: serial: qcom-geni-serial: Add a poll_init() function")
Cc: stable@vger.kernel.org # 6.4
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20241009145110.16847-2-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When sending data using DMA at high baudrate (4 Mbdps in local test case) to
a device with small RX buffer which keeps asserting RTS after every received
byte, it is possible that the iMX UART driver would not recognize the falling
edge of RTS input signal and get stuck, unable to transmit any more data.
This condition happens when the following sequence of events occur:
- imx_uart_mctrl_check() is called at some point and takes a snapshot of UART
control signal status into sport->old_status using imx_uart_get_hwmctrl().
The RTSS/TIOCM_CTS bit is of interest here (*).
- DMA transfer occurs, the remote device asserts RTS signal after each byte.
The i.MX UART driver recognizes each such RTS signal change, raises an
interrupt with USR1 register RTSD bit set, which leads to invocation of
__imx_uart_rtsint(), which calls uart_handle_cts_change().
- If the RTS signal is deasserted, uart_handle_cts_change() clears
port->hw_stopped and unblocks the port for further data transfers.
- If the RTS is asserted, uart_handle_cts_change() sets port->hw_stopped
and blocks the port for further data transfers. This may occur as the
last interrupt of a transfer, which means port->hw_stopped remains set
and the port remains blocked (**).
- Any further data transfer attempts will trigger imx_uart_mctrl_check(),
which will read current status of UART control signals by calling
imx_uart_get_hwmctrl() (***) and compare it with sport->old_status .
- If current status differs from sport->old_status for RTS signal,
uart_handle_cts_change() is called and possibly unblocks the port
by clearing port->hw_stopped .
- If current status does not differ from sport->old_status for RTS
signal, no action occurs. This may occur in case prior snapshot (*)
was taken before any transfer so the RTS is deasserted, current
snapshot (***) was taken after a transfer and therefore RTS is
deasserted again, which means current status and sport->old_status
are identical. In case (**) triggered when RTS got asserted, and
made port->hw_stopped set, the port->hw_stopped will remain set
because no change on RTS line is recognized by this driver and
uart_handle_cts_change() is not called from here to unblock the
port->hw_stopped.
Update sport->old_status in __imx_uart_rtsint() accordingly to make
imx_uart_mctrl_check() detect such RTS change. Note that TIOCM_CAR
and TIOCM_RI bits in sport->old_status do not suffer from this problem.
Fixes: ceca629e0b48 ("[ARM] 2971/1: i.MX uart handle rts irq")
Cc: stable <stable@kernel.org>
Reviewed-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20241002184133.19427-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
BUG: KASAN: slab-use-after-free in gsm_cleanup_mux+0x77b/0x7b0
drivers/tty/n_gsm.c:3160 [n_gsm]
Read of size 8 at addr ffff88815fe99c00 by task poc/3379
CPU: 0 UID: 0 PID: 3379 Comm: poc Not tainted 6.11.0+ #56
Hardware name: VMware, Inc. VMware Virtual Platform/440BX
Desktop Reference Platform, BIOS 6.00 11/12/2020
Call Trace:
<TASK>
gsm_cleanup_mux+0x77b/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]
__pfx_gsm_cleanup_mux+0x10/0x10 drivers/tty/n_gsm.c:3124 [n_gsm]
__pfx_sched_clock_cpu+0x10/0x10 kernel/sched/clock.c:389
update_load_avg+0x1c1/0x27b0 kernel/sched/fair.c:4500
__pfx_min_vruntime_cb_rotate+0x10/0x10 kernel/sched/fair.c:846
__rb_insert_augmented+0x492/0xbf0 lib/rbtree.c:161
gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]
_raw_spin_lock_irqsave+0x92/0xf0 arch/x86/include/asm/atomic.h:107
__pfx_gsmld_ioctl+0x10/0x10 drivers/tty/n_gsm.c:3822 [n_gsm]
ktime_get+0x5e/0x140 kernel/time/timekeeping.c:195
ldsem_down_read+0x94/0x4e0 arch/x86/include/asm/atomic64_64.h:79
__pfx_ldsem_down_read+0x10/0x10 drivers/tty/tty_ldsem.c:338
__pfx_do_vfs_ioctl+0x10/0x10 fs/ioctl.c:805
tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818
Allocated by task 65:
gsm_data_alloc.constprop.0+0x27/0x190 drivers/tty/n_gsm.c:926 [n_gsm]
gsm_send+0x2c/0x580 drivers/tty/n_gsm.c:819 [n_gsm]
gsm1_receive+0x547/0xad0 drivers/tty/n_gsm.c:3038 [n_gsm]
gsmld_receive_buf+0x176/0x280 drivers/tty/n_gsm.c:3609 [n_gsm]
tty_ldisc_receive_buf+0x101/0x1e0 drivers/tty/tty_buffer.c:391
tty_port_default_receive_buf+0x61/0xa0 drivers/tty/tty_port.c:39
flush_to_ldisc+0x1b0/0x750 drivers/tty/tty_buffer.c:445
process_scheduled_works+0x2b0/0x10d0 kernel/workqueue.c:3229
worker_thread+0x3dc/0x950 kernel/workqueue.c:3391
kthread+0x2a3/0x370 kernel/kthread.c:389
ret_from_fork+0x2d/0x70 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:257
Freed by task 3367:
kfree+0x126/0x420 mm/slub.c:4580
gsm_cleanup_mux+0x36c/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]
gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]
tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818
[Analysis]
gsm_msg on the tx_ctrl_list or tx_data_list of gsm_mux
can be freed by multi threads through ioctl,which leads
to the occurrence of uaf. Protect it by gsm tx lock.
Signed-off-by: Longlong Xia <xialonglong@kylinos.cn>
Cc: stable <stable@kernel.org>
Suggested-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240926130213.531959-1-xialonglong@kylinos.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
font.data may not initialize all memory spaces depending on the implementation
of vc->vc_sw->con_font_get. This may cause info-leak, so to prevent this, it
is safest to modify it to initialize the allocated memory space to 0, and it
generally does not affect the overall performance of the system.
Cc: stable@vger.kernel.org
Reported-by: syzbot+955da2d57931604ee691@syzkaller.appspotmail.com
Fixes: 05e2600cb0a4 ("VT: Bump font size limitation to 64x128 pixels")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Link: https://lore.kernel.org/r/20241010174619.59662-1-aha310510@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull Kbuild fixes from Masahiro Yamada:
- Move non-boot built-in DTBs to the .rodata section
- Fix Kconfig bugs
- Fix maint scripts in the linux-image Debian package
- Import some list macros to scripts/include/
* tag 'kbuild-fixes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: deb-pkg: Remove blank first line from maint scripts
kbuild: fix a typo dt_binding_schema -> dt_binding_schemas
scripts: import more list macros
kconfig: qconf: fix buffer overflow in debug links
kconfig: qconf: move conf_read() before drawing tree pain
kconfig: clear expr::val_is_valid when allocated
kconfig: fix infinite loop in sym_calc_choice()
kbuild: move non-boot built-in DTBs to .rodata section
Pull x86 platform driver fixes from Hans de Goede:
- Intel PMC fix for suspend/resume issues on some Sky and Kaby Lake
laptops
- Intel Diamond Rapids hw-id additions
- Documentation and MAINTAINERS fixes
- Some other small fixes
* tag 'platform-drivers-x86-v6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
platform/x86: x86-android-tablets: Fix use after free on platform_device_register() errors
platform/x86: wmi: Update WMI driver API documentation
platform/x86: dell-ddv: Fix typo in documentation
platform/x86: dell-sysman: add support for alienware products
platform/x86/intel: power-domains: Add Diamond Rapids support
platform/x86: ISST: Add Diamond Rapids to support list
platform/x86:intel/pmc: Disable ACPI PM Timer disabling on Sky and Kaby Lake
platform/x86: dell-laptop: Do not fail when encountering unsupported batteries
MAINTAINERS: Update Intel In Field Scan(IFS) entry
platform/x86: ISST: Fix the KASAN report slab-out-of-bounds bug
The blank line causes execve() to fail:
# strace ./postinst
execve("./postinst", ...) = -1 ENOEXEC (Exec format error)
strace: exec: Exec format error
+++ exited with 1 +++
However running the scripts via shell does work (at least with bash)
because the shell attempts to execute the file as a shell script when
execve() fails.
Fixes: b611daae5efc ("kbuild: deb-pkg: split image and debug objects staging out into functions")
Signed-off-by: Aaron Thompson <dev@aaront.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull kvm fixes from Paolo Bonzini:
"ARM64:
- Fix pKVM error path on init, making sure we do not change critical
system registers as we're about to fail
- Make sure that the host's vector length is at capped by a value
common to all CPUs
- Fix kvm_has_feat*() handling of "negative" features, as the current
code is pretty broken
- Promote Joey to the status of official reviewer, while James steps
down -- hopefully only temporarly
x86:
- Fix compilation with KVM_INTEL=KVM_AMD=n
- Fix disabling KVM_X86_QUIRK_SLOT_ZAP_ALL when shadow MMU is in use
Selftests:
- Fix compilation on non-x86 architectures"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
x86/reboot: emergency callbacks are now registered by common KVM code
KVM: x86: leave kvm.ko out of the build if no vendor module is requested
KVM: x86/mmu: fix KVM_X86_QUIRK_SLOT_ZAP_ALL for shadow MMU
KVM: arm64: Fix kvm_has_feat*() handling of negative features
KVM: selftests: Fix build on architectures other than x86_64
KVM: arm64: Another reviewer reshuffle
KVM: arm64: Constrain the host to the maximum shared SVE VL with pKVM
KVM: arm64: Fix __pkvm_init_vcpu cptr_el2 error path
x86_android_tablet_remove() frees the pdevs[] array, so it should not
be used after calling x86_android_tablet_remove().
When platform_device_register() fails, store the pdevs[x] PTR_ERR() value
into the local ret variable before calling x86_android_tablet_remove()
to avoid using pdevs[] after it has been freed.
Fixes: 5eba0141206e ("platform/x86: x86-android-tablets: Add support for instantiating platform-devs")
Fixes: e2200d3f26da ("platform/x86: x86-android-tablets: Add gpio_keys support to x86_android_tablet_init()")
Cc: stable@vger.kernel.org
Reported-by: Aleksandr Burakov <a.burakov@rosalinux.ru>
Closes: https://lore.kernel.org/platform-driver-x86/20240917120458.7300-1-a.burakov@rosalinux.ru/
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20241005130545.64136-1-hdegoede@redhat.com
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