linux-stable.git/drivers/tty, branch v3.16.40

tty: Prevent ldisc drivers from re-using stale tty fields

2017-02-23T03:54:44+00:00

commit dd42bf1197144ede075a9d4793123f7689e164bc upstream.

Line discipline drivers may mistakenly misuse ldisc-related fields
when initializing. For example, a failure to initialize tty->receive_room
in the N_GIGASET_M101 line discipline was recently found and fixed [1].
Now, the N_X25 line discipline has been discovered accessing the previous
line discipline's already-freed private data [2].

Harden the ldisc interface against misuse by initializing revelant
tty fields before instancing the new line discipline.

[1]
    commit fd98e9419d8d622a4de91f76b306af6aa627aa9c
    Author: Tilman Schmidt 
    Date:   Tue Jul 14 00:37:13 2015 +0200

    isdn/gigaset: reset tty->receive_room when attaching ser_gigaset

[2] Report from Sasha Levin 
    [  634.336761] ==================================================================
    [  634.338226] BUG: KASAN: use-after-free in x25_asy_open_tty+0x13d/0x490 at addr ffff8800a743efd0
    [  634.339558] Read of size 4 by task syzkaller_execu/8981
    [  634.340359] =============================================================================
    [  634.341598] BUG kmalloc-512 (Not tainted): kasan: bad access detected
    ...
    [  634.405018] Call Trace:
    [  634.405277] dump_stack (lib/dump_stack.c:52)
    [  634.405775] print_trailer (mm/slub.c:655)
    [  634.406361] object_err (mm/slub.c:662)
    [  634.406824] kasan_report_error (mm/kasan/report.c:138 mm/kasan/report.c:236)
    [  634.409581] __asan_report_load4_noabort (mm/kasan/report.c:279)
    [  634.411355] x25_asy_open_tty (drivers/net/wan/x25_asy.c:559 (discriminator 1))
    [  634.413997] tty_ldisc_open.isra.2 (drivers/tty/tty_ldisc.c:447)
    [  634.414549] tty_set_ldisc (drivers/tty/tty_ldisc.c:567)
    [  634.415057] tty_ioctl (drivers/tty/tty_io.c:2646 drivers/tty/tty_io.c:2879)
    [  634.423524] do_vfs_ioctl (fs/ioctl.c:43 fs/ioctl.c:607)
    [  634.427491] SyS_ioctl (fs/ioctl.c:622 fs/ioctl.c:613)
    [  634.427945] entry_SYSCALL_64_fastpath (arch/x86/entry/entry_64.S:188)

Cc: Tilman Schmidt 
Cc: Sasha Levin 
Signed-off-by: Peter Hurley 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

vt: clear selection before resizing

2017-02-23T03:54:22+00:00

commit 009e39ae44f4191188aeb6dfbf661b771dbbe515 upstream.

When resizing a vt its selection may exceed the new size, resulting in
an invalid memory access [1]. Clear the selection before resizing.

[1] http://lkml.kernel.org/r/CACT4Y+acDTwy4umEvf5ROBGiRJNrxHN4Cn5szCXE5Jw-d1B=Xw@mail.gmail.com

Reported-and-tested-by: Dmitry Vyukov 
Signed-off-by: Scot Doyle 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

tty: limit terminal size to 4M chars

2017-02-23T03:54:22+00:00

commit 32b2921e6a7461fe63b71217067a6cf4bddb132f upstream.

Size of kmalloc() in vc_do_resize() is controlled by user.
Too large kmalloc() size triggers WARNING message on console.
Put a reasonable upper bound on terminal size to prevent WARNINGs.

Signed-off-by: Dmitry Vyukov 
CC: David Rientjes 
Cc: One Thousand Gnomes 
Cc: Greg Kroah-Hartman 
Cc: Jiri Slaby 
Cc: Peter Hurley 
Cc: linux-kernel@vger.kernel.org
Cc: syzkaller@googlegroups.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

tty: vt, fix bogus division in csi_J

2017-02-23T03:54:22+00:00

commit 42acfc6615f47e465731c263bee0c799edb098f2 upstream.

In csi_J(3), the third parameter of scr_memsetw (vc_screenbuf_size) is
divided by 2 inappropriatelly. But scr_memsetw expects size, not
count, because it divides the size by 2 on its own before doing actual
memset-by-words.

So remove the bogus division.

Signed-off-by: Jiri Slaby 
Cc: Petr Písař 
Fixes: f8df13e0a9 (tty: Clean console safely)
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

serial: 8250: added acces i/o products quad and octal serial cards

2016-11-20T01:17:20+00:00

commit c8d192428f52f244130b84650ad616df09f2b1e1 upstream.

Added devices ids for acces i/o products quad and octal serial cards
that make use of existing Pericom PI7C9X7954 and PI7C9X7958
configurations .

Signed-off-by: Jimi Damon 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

sparc: serial: sunhv: fix a double lock bug

2016-11-20T01:16:59+00:00

commit 344e3c7734d5090b148c19ac6539b8947fed6767 upstream.

We accidentally take the "port->lock" twice in a row.  This old code
was supposed to be deleted.

Fixes: e58e241c1788 ('sparc: serial: Clean up the locking for -rt')
Signed-off-by: Dan Carpenter 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

tty/vt/keyboard: fix OOB access in do_compute_shiftstate()

2016-11-20T01:16:56+00:00

commit 510cccb5b0c8868a2b302a0ab524da7912da648b upstream.

The size of individual keymap in drivers/tty/vt/keyboard.c is NR_KEYS,
which is currently 256, whereas number of keys/buttons in input device (and
therefor in key_down) is much larger - KEY_CNT - 768, and that can cause
out-of-bound access when we do

	sym = U(key_maps[0][k]);

with large 'k'.

To fix it we should not attempt iterating beyond smaller of NR_KEYS and
KEY_CNT.

Also while at it let's switch to for_each_set_bit() instead of open-coding
it.

Reported-by: Sasha Levin 
Reviewed-by: Guenter Roeck 
Signed-off-by: Dmitry Torokhov 
Signed-off-by: Ben Hutchings

serial: samsung: Fix possible out of bounds access on non-DT platform

2016-11-20T01:16:42+00:00

commit 926b7b5122c96e1f18cd20e85a286c7ec8d18c97 upstream.

On non-DeviceTree platforms, the index of serial device is a static
variable incremented on each probe.  It is incremented even if deferred
probe happens when getting the clock in s3c24xx_serial_init_port().

This index is used for referencing elements of statically allocated
s3c24xx_serial_ports array.  In case of re-probe, the index will point
outside of this array leading to memory corruption.

Increment the index only on successful probe.

Reported-by: Bartlomiej Zolnierkiewicz 
Fixes: b497549a035c ("[ARM] S3C24XX: Split serial driver into core and per-cpu drivers")
Signed-off-by: Krzysztof Kozlowski 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

serial: samsung: Fix ERR pointer dereference on deferred probe

2016-11-20T01:16:42+00:00

commit e51e4d8a185de90424b03f30181b35f29c46a25a upstream.

When the clk_get() of "uart" clock returns EPROBE_DEFER, the next re-probe
finishes with success but uses invalid (ERR_PTR) values.  This leads to
dereferencing of ERR_PTR stored under ourport->clk:

	12c30000.serial: Controller clock not found
	(...)
	12c30000.serial: ttySAC3 at MMIO 0x12c30000 (irq = 61, base_baud = 0) is a S3C6400/10
	Unable to handle kernel paging request at virtual address fffffdfb

	(clk_prepare) from [] (s3c24xx_serial_pm+0x20/0x128)
	(s3c24xx_serial_pm) from [] (uart_change_pm+0x38/0x40)
	(uart_change_pm) from [] (uart_add_one_port+0x31c/0x44c)
	(uart_add_one_port) from [] (s3c24xx_serial_probe+0x2a8/0x418)
	(s3c24xx_serial_probe) from [] (platform_drv_probe+0x50/0xb0)
	(platform_drv_probe) from [] (driver_probe_device+0x1f4/0x2b0)
	(driver_probe_device) from [] (bus_for_each_drv+0x44/0x8c)
	(bus_for_each_drv) from [] (__device_attach+0x9c/0x100)
	(__device_attach) from [] (bus_probe_device+0x84/0x8c)
	(bus_probe_device) from [] (deferred_probe_work_func+0x60/0x8c)
	(deferred_probe_work_func) from [] (process_one_work+0x120/0x328)
	(process_one_work) from [] (worker_thread+0x2c/0x4ac)
	(worker_thread) from [] (kthread+0xd8/0xf4)
	(kthread) from [] (ret_from_fork+0x14/0x3c)

The first unsuccessful clk_get() causes s3c24xx_serial_init_port() to
exit with failure but the s3c24xx_uart_port is left half-configured
(e.g. port->mapbase is set, clk contains ERR_PTR).  On next re-probe,
the function s3c24xx_serial_init_port() will exit early with success
because of configured port->mapbase and driver will use old values,
including the ERR_PTR as clock.

Fix this by cleaning the port->mapbase on error path so each re-probe
will initialize all of the port settings.

Fixes: 60e93575476f ("serial: samsung: enable clock before clearing pending interrupts during init")
Signed-off-by: Krzysztof Kozlowski 
Reviewed-by: Javier Martinez Canillas 
Tested-by: Javier Martinez Canillas 
Tested-by: Kevin Hilman 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: driver doesn't set up DMA here]
Signed-off-by: Ben Hutchings

tty/serial: atmel: fix RS485 half duplex with DMA

2016-11-20T01:16:42+00:00

commit 0058f0871efe7b01c6f2b3046c68196ab73e96da upstream.

When using DMA, half duplex doesn't work properly because rx is not stopped
before starting tx. Ensure we call atmel_stop_rx() in the DMA case.

Signed-off-by: Alexandre Belloni 
Acked-by: Nicolas Ferre 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16:
 - Adjust context
 - Keep using UART_GET_PTSR()]
Signed-off-by: Ben Hutchings