linux-stable.git/drivers/tty, branch v3.18.92

n_tty: fix EXTPROC vs ICANON interaction with TIOCINQ (aka FIONREAD)

2018-01-02T19:04:59+00:00

commit 966031f340185eddd05affcf72b740549f056348 upstream.

We added support for EXTPROC back in 2010 in commit 26df6d13406d ("tty:
Add EXTPROC support for LINEMODE") and the intent was to allow it to
override some (all?) ICANON behavior.  Quoting from that original commit
message:

         There is a new bit in the termios local flag word, EXTPROC.
         When this bit is set, several aspects of the terminal driver
         are disabled.  Input line editing, character echo, and mapping
         of signals are all disabled.  This allows the telnetd to turn
         off these functions when in linemode, but still keep track of
         what state the user wants the terminal to be in.

but the problem turns out that "several aspects of the terminal driver
are disabled" is a bit ambiguous, and you can really confuse the n_tty
layer by setting EXTPROC and then causing some of the ICANON invariants
to no longer be maintained.

This fixes at least one such case (TIOCINQ) becoming unhappy because of
the confusion over whether ICANON really means ICANON when EXTPROC is set.

This basically makes TIOCINQ match the case of read: if EXTPROC is set,
we ignore ICANON.  Also, make sure to reset the ICANON state ie EXTPROC
changes, not just if ICANON changes.

Fixes: 26df6d13406d ("tty: Add EXTPROC support for LINEMODE")
Reported-by: Tetsuo Handa 
Reported-by: syzkaller 
Cc: Jiri Slaby 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Add Amazon PCI serial device ID

2017-12-09T17:29:48+00:00

commit 3bfd1300abfe3adb18e84a89d97a0e82a22124bb upstream.

This device will be used in future Amazon EC2 instances as the primary
serial port (i.e., data sent to this port will be available via the
GetConsoleOuput [1] EC2 API).

[1] http://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_GetConsoleOutput.html

Signed-off-by: Matt Wilson 
Signed-off-by: Greg Kroah-Hartman

sysrq : fix Show Regs call trace on ARM

2017-12-09T17:29:47+00:00

[ Upstream commit b00bebbc301c8e1f74f230dc82282e56b7e7a6db ]

When kernel configuration SMP,PREEMPT and DEBUG_PREEMPT are enabled,
echo 1 >/proc/sys/kernel/sysrq
echo p >/proc/sysrq-trigger
kernel will print call trace as below:

sysrq: SysRq : Show Regs
BUG: using __this_cpu_read() in preemptible [00000000] code: sh/435
caller is __this_cpu_preempt_check+0x18/0x20
Call trace:
[] dump_backtrace+0x0/0x1d0
[] show_stack+0x24/0x30
[] dump_stack+0x90/0xb0
[] check_preemption_disabled+0x100/0x108
[] __this_cpu_preempt_check+0x18/0x20
[] sysrq_handle_showregs+0x1c/0x40
[] __handle_sysrq+0x12c/0x1a0
[] write_sysrq_trigger+0x60/0x70
[] proc_reg_write+0x90/0xd0
[] __vfs_write+0x48/0x90
[] vfs_write+0xa4/0x190
[] SyS_write+0x54/0xb0
[] el0_svc_naked+0x24/0x28

This can be seen on a common board like an r-pi3.
This happens because when echo p >/proc/sysrq-trigger,
get_irq_regs() is called outside of IRQ context,
if preemption is enabled in this situation,kernel will
print the call trace. Since many prior discussions on
the mailing lists have made it clear that get_irq_regs
either just returns NULL or stale data when used outside
of IRQ context,we simply avoid calling it outside of
IRQ context.

Signed-off-by: Jibin Xu 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_fintek: Fix rs485 disablement on invalid ioctl()

2017-12-09T17:29:47+00:00

[ Upstream commit 3236a965486ba0c6043cf2c7b51943d8b382ae29 ]

This driver's ->rs485_config callback checks if SER_RS485_RTS_ON_SEND
and SER_RS485_RTS_AFTER_SEND have the same value.  If they do, it means
the user has passed in invalid data with the TIOCSRS485 ioctl()
since RTS must have a different polarity when sending and when not
sending.  In this case, rs485 mode is not enabled (the RS485_URA bit
is not set in the RS485 Enable Register) and this is supposed to be
signaled back to the user by clearing the SER_RS485_ENABLED bit in
struct serial_rs485 ... except a missing tilde character is preventing
that from happening.

Fixes: 28e3fb6c4dce ("serial: Add support for Fintek F81216A LPC to 4 UART")
Cc: Ricardo Ribalda Delgado 
Cc: "Ji-Ze Hong (Peter Hong)" 
Signed-off-by: Lukas Wunner 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix register offsets for the IRDA serial port

2017-11-15T09:04:12+00:00

[ Upstream commit a752ba18af8285e3eeda572f40dddaebff0c3621 ]

Even though most of its registers are 8-bit wide, the IRDA has two
16-bit registers that make it a 16-bit peripheral and not a 8-bit
peripheral with addresses shifted by one. Fix the registers offset in
the driver and the platform data regshift value.

Signed-off-by: Laurent Pinchart 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Revert "tty: goldfish: Fix a parameter of a call to free_irq"

2017-10-21T15:07:27+00:00

This reverts commit 0961072120f3e40fe98c2bb49c45549ca3f042dc which is
commit 1a5c2d1de7d35f5eb9793266237903348989502b upstream.

Ben writes:
	This fixes a bug introduced in 4.6 by commit 465893e18878 "tty:
	goldfish: support platform_device with id -1".  For earlier
	kernel versions, it *introduces* a bug.

So let's drop it.

Reported-by: Ben Hutchings 
Cc: Christophe JAILLET 
Cc: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

tty: goldfish: Fix a parameter of a call to free_irq

2017-10-08T08:11:19+00:00

[ Upstream commit 1a5c2d1de7d35f5eb9793266237903348989502b ]

'request_irq()' and 'free_irq()' should be called with the same dev_id.

Signed-off-by: Christophe JAILLET 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

vt: fix unchecked __put_user() in tioclinux ioctls

2017-07-21T06:12:23+00:00

commit 6987dc8a70976561d22450b5858fc9767788cc1c upstream.

Only read access is checked before this call.

Actually, at the moment this is not an issue, as every in-tree arch does
the same manual checks for VERIFY_READ vs VERIFY_WRITE, relying on the MMU
to tell them apart, but this wasn't the case in the past and may happen
again on some odd arch in the future.

If anyone cares about 3.7 and earlier, this is a security hole (untested)
on real 80386 CPUs.

Signed-off-by: Adam Borowski 
Signed-off-by: Greg Kroah-Hartman

serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'

2017-06-26T05:10:50+00:00

commit be40597a1bc173bf9dadccdf5388b956f620ae8f upstream.

UARTn_FRAME_PARITY_ODD is 0x0300
UARTn_FRAME_PARITY_EVEN is 0x0200
So if the UART is configured for EVEN parity, it would be reported as ODD.
Fix it by correctly testing if the 2 bits are set.

Fixes: 3afbd89c9639 ("serial/efm32: add new driver")
Signed-off-by: Christophe JAILLET 
Acked-by: Uwe Kleine-König 
Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix panic when serial console and DMA are enabled

2017-06-14T10:54:20+00:00

commit 3c9101766b502a0163d1d437fada5801cf616be2 upstream.

This patch fixes an issue that kernel panic happens when DMA is enabled
and we press enter key while the kernel booting on the serial console.

* An interrupt may occur after sci_request_irq().
* DMA transfer area is initialized by setup_timer() in sci_request_dma()
  and used in interrupt.

If an interrupt occurred between sci_request_irq() and setup_timer() in
sci_request_dma(), DMA transfer area has not been initialized yet.
So, this patch changes the order of sci_request_irq() and
sci_request_dma().

Fixes: 73a19e4c0301 ("serial: sh-sci: Add DMA support.")
Signed-off-by: Takatoshi Akiyama 
[Shimoda changes the commit log]
Signed-off-by: Yoshihiro Shimoda 
Cc: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman