tjh.dev
Linux kernel
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Pull USB fixes from Greg KH:
"Here are some small USB fixes that resolve some reported problems.
These include:
- gadget driver fixes
- dwc3 driver fix
- typec driver fix
- MAINTAINERS file update.
All of these have been in linux-next with no reported problems"
* tag 'usb-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: typec: ucsi: Don't attempt to resume the ports before they exist
usb: gadget: udc: do not clear gadget driver.bus
usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints
usb: gadget: f_fs: Fix unbalanced spinlock in __ffs_ep0_queue_wait
usb: dwc3: qcom: enable vbus override when in OTG dr-mode
MAINTAINERS: Add myself as UVC Gadget Maintainer
Pull tty/serial driver fixes from Greg KH:
"Here are some small serial and vt fixes. These include:
- 8250 driver fixes relating to dma issues
- stm32 serial driver fix for threaded irqs
- vc_screen bugfix for reported problems.
All have been in linux-next for a while with no reported problems"
* tag 'tty-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
vc_screen: move load of struct vc_data pointer in vcs_read() to avoid UAF
serial: 8250_dma: Fix DMA Rx rearm race
serial: 8250_dma: Fix DMA Rx completion race
serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler
This will fix null pointer dereference that was caused by
the driver attempting to resume ports that were not yet
registered.
Fixes: e0dced9c7d47 ("usb: typec: ucsi: Resume in separate work")
Cc: <stable@vger.kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216697
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230131141518.78215-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull char/misc driver fixes from Greg KH:
"Here are a number of small char/misc/whatever driver fixes. They
include:
- IIO driver fixes for some reported problems
- nvmem driver fixes
- fpga driver fixes
- debugfs memory leak fix in the hv_balloon and irqdomain code
(irqdomain change was acked by the maintainer)
All have been in linux-next with no reported problems"
* tag 'char-misc-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (33 commits)
kernel/irq/irqdomain.c: fix memory leak with using debugfs_lookup()
HV: hv_balloon: fix memory leak with using debugfs_lookup()
nvmem: qcom-spmi-sdam: fix module autoloading
nvmem: core: fix return value
nvmem: core: fix cell removal on error
nvmem: core: fix device node refcounting
nvmem: core: fix registration vs use race
nvmem: core: fix cleanup after dev_set_name()
nvmem: core: remove nvmem_config wp_gpio
nvmem: core: initialise nvmem->id early
nvmem: sunxi_sid: Always use 32-bit MMIO reads
nvmem: brcm_nvram: Add check for kzalloc
iio: imu: fxos8700: fix MAGN sensor scale and unit
iio: imu: fxos8700: remove definition FXOS8700_CTRL_ODR_MIN
iio: imu: fxos8700: fix failed initialization ODR mode assignment
iio: imu: fxos8700: fix incorrect ODR mode readback
iio: light: cm32181: Fix PM support on system with 2 I2C resources
iio: hid: fix the retval in gyro_3d_capture_sample
iio: hid: fix the retval in accel_3d_capture_sample
iio: imu: st_lsm6dsx: fix build when CONFIG_IIO_TRIGGERED_BUFFER=m
...
After a call to console_unlock() in vcs_read() the vc_data struct can be
freed by vc_deallocate(). Because of that, the struct vc_data pointer
load must be done at the top of while loop in vcs_read() to avoid a UAF
when vcs_size() is called.
Syzkaller reported a UAF in vcs_size().
BUG: KASAN: use-after-free in vcs_size (drivers/tty/vt/vc_screen.c:215)
Read of size 4 at addr ffff8881137479a8 by task 4a005ed81e27e65/1537
CPU: 0 PID: 1537 Comm: 4a005ed81e27e65 Not tainted 6.2.0-rc5 #1
Hardware name: Red Hat KVM, BIOS 1.15.0-2.module
Call Trace:
<TASK>
__asan_report_load4_noabort (mm/kasan/report_generic.c:350)
vcs_size (drivers/tty/vt/vc_screen.c:215)
vcs_read (drivers/tty/vt/vc_screen.c:415)
vfs_read (fs/read_write.c:468 fs/read_write.c:450)
...
</TASK>
Allocated by task 1191:
...
kmalloc_trace (mm/slab_common.c:1069)
vc_allocate (./include/linux/slab.h:580 ./include/linux/slab.h:720
drivers/tty/vt/vt.c:1128 drivers/tty/vt/vt.c:1108)
con_install (drivers/tty/vt/vt.c:3383)
tty_init_dev (drivers/tty/tty_io.c:1301 drivers/tty/tty_io.c:1413
drivers/tty/tty_io.c:1390)
tty_open (drivers/tty/tty_io.c:2080 drivers/tty/tty_io.c:2126)
chrdev_open (fs/char_dev.c:415)
do_dentry_open (fs/open.c:883)
vfs_open (fs/open.c:1014)
...
Freed by task 1548:
...
kfree (mm/slab_common.c:1021)
vc_port_destruct (drivers/tty/vt/vt.c:1094)
tty_port_destructor (drivers/tty/tty_port.c:296)
tty_port_put (drivers/tty/tty_port.c:312)
vt_disallocate_all (drivers/tty/vt/vt_ioctl.c:662 (discriminator 2))
vt_ioctl (drivers/tty/vt/vt_ioctl.c:903)
tty_ioctl (drivers/tty/tty_io.c:2776)
...
The buggy address belongs to the object at ffff888113747800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 424 bytes inside of
1024-byte region [ffff888113747800, ffff888113747c00)
The buggy address belongs to the physical page:
page:00000000b3fe6c7c refcount:1 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x113740
head:00000000b3fe6c7c order:3 compound_mapcount:0 subpages_mapcount:0
compound_pincount:0
anon flags: 0x17ffffc0010200(slab|head|node=0|zone=2|lastcpupid=0x1fffff)
raw: 0017ffffc0010200 ffff888100042dc0 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888113747880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888113747900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff888113747980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888113747a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888113747a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Disabling lock debugging due to kernel taint
Fixes: ac751efa6a0d ("console: rename acquire/release_console_sem() to console_lock/unlock()")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Suggested-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Link: https://lore.kernel.org/r/1674577014-12374-1-git-send-email-george.kennedy@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before the commit fc274c1e9973 ("USB: gadget: Add a new bus for gadgets")
gadget driver.bus was unused. For whatever reason, many UDC drivers set
this field explicitly to NULL in udc_start(). With the newly added gadget
bus, doing this will crash the driver during the attach.
The problem was first reported, fixed and tested with OMAP UDC and g_ether.
Other drivers are changed based on code analysis only.
Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets")
Cc: stable <stable@kernel.org>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20230201220125.GD2415@darkstar.musicnaut.iki.fi
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull fbdev fixes from Helge Deller:
- fix fbcon to prevent fonts bigger than 32x32 pixels to avoid
overflows reported by syzbot
- switch omapfb to use kstrtobool()
- switch some fbdev drivers to use the backlight helpers
* tag 'fbdev-for-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
fbcon: Check font dimension limits
fbdev: omapfb: Use kstrtobool() instead of strtobool()
fbdev: fbmon: fix function name in kernel-doc
fbdev: atmel_lcdfb: Rework backlight status updates
fbdev: riva: Use backlight helper
fbdev: omapfb: panel-dsi-cm: Use backlight helper
fbdev: nvidia: Use backlight helper
fbdev: mx3fb: Use backlight helper
fbdev: radeon: Use backlight helper
fbdev: atyfb: Use backlight helper
fbdev: aty128fb: Use backlight helper
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable <stable@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230202151554.2310273-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As DMA Rx can be completed from two places, it is possible that DMA Rx
completes before DMA completion callback had a chance to complete it.
Once the previous DMA Rx has been completed, a new one can be started
on the next UART interrupt. The following race is possible
(uart_unlock_and_check_sysrq_irqrestore() replaced with
spin_unlock_irqrestore() for simplicity/clarity):
CPU0 CPU1
dma_rx_complete()
serial8250_handle_irq()
spin_lock_irqsave(&port->lock)
handle_rx_dma()
serial8250_rx_dma_flush()
__dma_rx_complete()
dma->rx_running = 0
// Complete DMA Rx
spin_unlock_irqrestore(&port->lock)
serial8250_handle_irq()
spin_lock_irqsave(&port->lock)
handle_rx_dma()
serial8250_rx_dma()
dma->rx_running = 1
// Setup a new DMA Rx
spin_unlock_irqrestore(&port->lock)
spin_lock_irqsave(&port->lock)
// sees dma->rx_running = 1
__dma_rx_complete()
dma->rx_running = 0
// Incorrectly complete
// running DMA Rx
This race seems somewhat theoretical to occur for real but handle it
correctly regardless. Check what is the DMA status before complething
anything in __dma_rx_complete().
Reported-by: Gilles BULOZ <gilles.buloz@kontron.com>
Tested-by: Gilles BULOZ <gilles.buloz@kontron.com>
Fixes: 9ee4b83e51f7 ("serial: 8250: Add support for dmaengine")
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230130114841.25749-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently connect/disconnect of USB cable calls afunc_bind and
eventually increments the bNumEndpoints. Performing multiple
plugin/plugout will increment bNumEndpoints incorrectly, and on
the next plug-in it leads to invalid configuration of descriptor
and hence enumeration fails.
Fix this by resetting the value of bNumEndpoints to 1 on every
afunc_bind call.
Fixes: 40c73b30546e ("usb: gadget: f_uac2: add adaptive sync support for capture")
Cc: stable <stable@kernel.org>
Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Link: https://lore.kernel.org/r/1674631645-28888-1-git-send-email-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull x86 fix from Borislav Petkov:
- Prevent the compiler from reordering accesses to debug regs which
could cause a #VC exception in SEV-ES guests at the wrong place in
the NMI handling path
* tag 'x86_urgent_for_v6.2_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Fix stack recursion caused by wrongly ordered DR7 accesses
blit_x and blit_y are u32, so fbcon currently cannot support fonts
larger than 32x32.
The 32x32 case also needs shifting an unsigned int, to properly set bit
31, otherwise we get "UBSAN: shift-out-of-bounds in fbcon_set_font",
as reported on:
http://lore.kernel.org/all/IA1PR07MB98308653E259A6F2CE94A4AFABCE9@IA1PR07MB9830.namprd07.prod.outlook.com
Kernel Branch: 6.2.0-rc5-next-20230124
Kernel config: https://drive.google.com/file/d/1F-LszDAizEEH0ZX0HcSR06v5q8FPl2Uv/view?usp=sharing
Reproducer: https://drive.google.com/file/d/1mP1jcLBY7vWCNM60OMf-ogw-urQRjNrm/view?usp=sharing
Reported-by: Sanan Hasanov <sanan.hasanov@Knights.ucf.edu>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Fixes: 2d2699d98492 ("fbcon: font setting should check limitation of driver")
Cc: stable@vger.kernel.org
Tested-by: Miko Larsson <mikoxyzzz@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Helge Deller <deller@gmx.de>
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Fixes: d180e0a1be6c ("Drivers: hv: Create debugfs file with hyper-v balloon usage information")
Cc: stable <stable@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20230202140918.2289522-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__dma_rx_complete() is called from two places:
- Through the DMA completion callback dma_rx_complete()
- From serial8250_rx_dma_flush() after IIR_RLSI or IIR_RX_TIMEOUT
The former does not hold port's lock during __dma_rx_complete() which
allows these two to race and potentially insert the same data twice.
Extend port's lock coverage in dma_rx_complete() to prevent the race
and check if the DMA Rx is still pending completion before calling
into __dma_rx_complete().
Reported-by: Gilles BULOZ <gilles.buloz@kontron.com>
Tested-by: Gilles BULOZ <gilles.buloz@kontron.com>
Fixes: 9ee4b83e51f7 ("serial: 8250: Add support for dmaengine")
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230130114841.25749-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__ffs_ep0_queue_wait executes holding the spinlock of &ffs->ev.waitq.lock
and unlocks it after the assignments to usb_request are done.
However in the code if the request is already NULL we bail out returning
-EINVAL but never unlocked the spinlock.
Fix this by adding spin_unlock_irq &ffs->ev.waitq.lock before returning.
Fixes: 6a19da111057 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait")
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Link: https://lore.kernel.org/r/20230124091149.18647-1-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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