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Linux kernel
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Pull HID fix from Jiri Kosina:
"A regression fix for EPOLLOUT handling in hidraw and uhid"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
HID: hidraw, uhid: Always report EPOLLOUT
Pull USB/PHY fixes from Greg KH:
"Here are a number of USB and PHY driver fixes for 5.5-rc6
Nothing all that unusual, just the a bunch of small fixes for a lot of
different reported issues. The PHY driver fixes are in here as they
interacted with the usb drivers.
Full details of the patches are in the shortlog, and all of these have
been in linux-next with no reported issues"
* tag 'usb-5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (24 commits)
usb: missing parentheses in USE_NEW_SCHEME
usb: ohci-da8xx: ensure error return on variable error is set
usb: musb: Disable pullup at init
usb: musb: fix idling for suspend after disconnect interrupt
usb: typec: ucsi: Fix the notification bit offsets
USB: Fix: Don't skip endpoint descriptors with maxpacket=0
USB-PD tcpm: bad warning+size, PPS adapters
phy/rockchip: inno-hdmi: round clock rate down to closest 1000 Hz
usb: chipidea: host: Disable port power only if previously enabled
usb: cdns3: should not use the same dev_id for shared interrupt handler
usb: dwc3: gadget: Fix request complete check
usb: musb: dma: Correct parameter passed to IRQ handler
usb: musb: jz4740: Silence error if code is -EPROBE_DEFER
usb: udc: tegra: select USB_ROLE_SWITCH
USB: core: fix check for duplicate endpoints
phy: cpcap-usb: Drop extra write to usb2 register
phy: cpcap-usb: Improve host vs docked mode detection
phy: cpcap-usb: Prevent USB line glitches from waking up modem
phy: mapphone-mdm6600: Fix uninitialized status value regression
phy: cpcap-usb: Fix flakey host idling and enumerating of devices
...
hidraw and uhid device nodes are always available for writing so we should
always report EPOLLOUT and EPOLLWRNORM bits, not only in the cases when
there is nothing to read.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: be54e7461ffdc ("HID: uhid: Fix returning EPOLLOUT from uhid_char_poll")
Fixes: 9f3b61dc1dd7b ("HID: hidraw: Fix returning EPOLLOUT from hidraw_poll")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Pull char/misc fix from Greg KH:
"Here is a single fix, for the chrdev core, for 5.5-rc6
There's been a long-standing race condition triggered by syzbot, and
occasionally real people, in the chrdev open() path. Will finally took
the time to track it down and fix it for real before the holidays.
Here's that one patch, it's been in linux-next for a while with no
reported issues and it does fix the reported problem"
* tag 'char-misc-5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
chardev: Avoid potential use-after-free in 'chrdev_open()'
According to bd0e6c9614b9 ("usb: hub: try old enumeration scheme first
for high speed devices") the kernel will try the old enumeration scheme
first for high speed devices. This can happen when a high speed device
is plugged in.
But due to missing parentheses in the USE_NEW_SCHEME define, this logic
can get messed up and the incorrect result happens.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Qi Zhou <atmgnd@outlook.com>
Link: https://lore.kernel.org/r/ht4mtag8ZP-HKEhD0KkJhcFnVlOFV8N8eNjJVRD9pDkkLUNhmEo8_cL_sl7xy9mdajdH-T8J3TFQsjvoYQT61NFjQXy469Ed_BbBw_x4S1E=@protonmail.com
[ fixup changelog text - gregkh]
Cc: stable <stable@vger.kernel.org>
Fixes: bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The `connected` value for wired devices was not properly initialized,
it must be set to `true` upon creation, because wired devices do not
generate connection events.
When a raw client (the Steam Client) uses the device, the input device
is destroyed. Then, when the raw client finishes, it must be recreated.
But since the `connected` variable was false this never happended.
Signed-off-by: Rodrigo Rivas Costa <rodrigorivascosta@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Pull staging fixes from Greg KH:
"Here are some small staging driver fixes for 5.5-rc6.
Nothing major here, just some small fixes for a comedi driver, the
vt6656 driver, and a new device id for the rtl8188eu driver.
All of these have been in linux-next for a while with no reported
issues"
* tag 'staging-5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: rtl8188eu: Add device code for TP-Link TL-WN727N v5.21
staging: comedi: adv_pci1710: fix AI channels 16-31 for PCI-1713
staging: vt6656: set usb_set_intfdata on driver fail.
staging: vt6656: remove bool from vnt_radio_power_on ret
staging: vt6656: limit reg output to block size
staging: vt6656: correct return of vnt_init_registers.
staging: vt6656: Fix non zero logical return of, usb_control_msg
'chrdev_open()' calls 'cdev_get()' to obtain a reference to the
'struct cdev *' stashed in the 'i_cdev' field of the target inode
structure. If the pointer is NULL, then it is initialised lazily by
looking up the kobject in the 'cdev_map' and so the whole procedure is
protected by the 'cdev_lock' spinlock to serialise initialisation of
the shared pointer.
Unfortunately, it is possible for the initialising thread to fail *after*
installing the new pointer, for example if the subsequent '->open()' call
on the file fails. In this case, 'cdev_put()' is called, the reference
count on the kobject is dropped and, if nobody else has taken a reference,
the release function is called which finally clears 'inode->i_cdev' from
'cdev_purge()' before potentially freeing the object. The problem here
is that a racing thread can happily take the 'cdev_lock' and see the
non-NULL pointer in the inode, which can result in a refcount increment
from zero and a warning:
| ------------[ cut here ]------------
| refcount_t: addition on 0; use-after-free.
| WARNING: CPU: 2 PID: 6385 at lib/refcount.c:25 refcount_warn_saturate+0x6d/0xf0
| Modules linked in:
| CPU: 2 PID: 6385 Comm: repro Not tainted 5.5.0-rc2+ #22
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
| RIP: 0010:refcount_warn_saturate+0x6d/0xf0
| Code: 05 55 9a 15 01 01 e8 9d aa c8 ff 0f 0b c3 80 3d 45 9a 15 01 00 75 ce 48 c7 c7 00 9c 62 b3 c6 08
| RSP: 0018:ffffb524c1b9bc70 EFLAGS: 00010282
| RAX: 0000000000000000 RBX: ffff9e9da1f71390 RCX: 0000000000000000
| RDX: ffff9e9dbbd27618 RSI: ffff9e9dbbd18798 RDI: ffff9e9dbbd18798
| RBP: 0000000000000000 R08: 000000000000095f R09: 0000000000000039
| R10: 0000000000000000 R11: ffffb524c1b9bb20 R12: ffff9e9da1e8c700
| R13: ffffffffb25ee8b0 R14: 0000000000000000 R15: ffff9e9da1e8c700
| FS: 00007f3b87d26700(0000) GS:ffff9e9dbbd00000(0000) knlGS:0000000000000000
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
| CR2: 00007fc16909c000 CR3: 000000012df9c000 CR4: 00000000000006e0
| DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
| DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
| Call Trace:
| kobject_get+0x5c/0x60
| cdev_get+0x2b/0x60
| chrdev_open+0x55/0x220
| ? cdev_put.part.3+0x20/0x20
| do_dentry_open+0x13a/0x390
| path_openat+0x2c8/0x1470
| do_filp_open+0x93/0x100
| ? selinux_file_ioctl+0x17f/0x220
| do_sys_open+0x186/0x220
| do_syscall_64+0x48/0x150
| entry_SYSCALL_64_after_hwframe+0x44/0xa9
| RIP: 0033:0x7f3b87efcd0e
| Code: 89 54 24 08 e8 a3 f4 ff ff 8b 74 24 0c 48 8b 3c 24 41 89 c0 44 8b 54 24 08 b8 01 01 00 00 89 f4
| RSP: 002b:00007f3b87d259f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
| RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b87efcd0e
| RDX: 0000000000000000 RSI: 00007f3b87d25a80 RDI: 00000000ffffff9c
| RBP: 00007f3b87d25e90 R08: 0000000000000000 R09: 0000000000000000
| R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe188f504e
| R13: 00007ffe188f504f R14: 00007f3b87d26700 R15: 0000000000000000
| ---[ end trace 24f53ca58db8180a ]---
Since 'cdev_get()' can already fail to obtain a reference, simply move
it over to use 'kobject_get_unless_zero()' instead of 'kobject_get()',
which will cause the racing thread to return -ENXIO if the initialising
thread fails unexpectedly.
Cc: Hillf Danton <hdanton@sina.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: syzbot+82defefbbd8527e1c2cb@syzkaller.appspotmail.com
Signed-off-by: Will Deacon <will@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191219120203.32691-1-will@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently when an error occurs when calling devm_gpiod_get_optional or
calling gpiod_to_irq it causes an uninitialized error return in variable
'error' to be returned. Fix this by ensuring the error variable is set
from da8xx_ohci->oc_gpio and oc_irq.
Thanks to Dan Carpenter for spotting the uninitialized error in the
gpiod_to_irq failure case.
Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: d193abf1c913 ("usb: ohci-da8xx: add vbus and overcurrent gpios")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20200107123901.101190-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Added Tiger Lake PCI device ID to the supported device list.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Pull tty/serial fixes from Greg KH:
"Here are two tty/serial driver fixes for 5.5-rc6.
The first fixes a much much reported issue with a previous tty port
link patch that is in your tree, and the second fixes a problem where
the serdev driver would claim ACPI devices that it shouldn't be
claiming.
Both have been in linux-next for a while with no reported issues"
* tag 'tty-5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serdev: Don't claim unsupported ACPI serial devices
tty: always relink the port
This device was added to the stand-alone driver on github.
Add it to the staging driver as well.
Link: https://github.com/lwfinger/rtl8188eu/commit/b9b537aa25a8
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191228143725.24455-1-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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