linux-stable.git/drivers/tty, branch linux-5.6.y Linux kernel stable tree tty: hvc_console, fix crashes on parallel open/close 2020-06-10T18:22:51+00:00 Jiri Slaby jslaby@suse.cz 2020-05-26T14:56:32+00:00 bdb6d7d8da28c97512b9130932c233eca1f92a8a commit 24eb2377f977fe06d84fca558f891f95bc28a449 upstream. hvc_open sets tty->driver_data to NULL when open fails at some point. Typically, the failure happens in hp->ops->notifier_add(). If there is a racing process which tries to open such mangled tty, which was not closed yet, the process will crash in hvc_open as tty->driver_data is NULL. All this happens because close wants to know whether open failed or not. But ->open should not NULL this and other tty fields for ->close to be happy. ->open should call tty_port_set_initialized(true) and close should check by tty_port_initialized() instead. So do this properly in this driver. So this patch removes these from ->open: * tty_port_tty_set(&hp->port, NULL). This happens on last close. * tty->driver_data = NULL. Dtto. * tty_port_put(&hp->port). This happens in shutdown and until now, this must have been causing a reference underflow, if I am not missing something. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@vger.kernel.org> Reported-and-tested-by: Raghavendra <rananta@codeaurora.org> Link: https://lore.kernel.org/r/20200526145632.13879-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 24eb2377f977fe06d84fca558f891f95bc28a449 upstream.

hvc_open sets tty->driver_data to NULL when open fails at some point.
Typically, the failure happens in hp->ops->notifier_add(). If there is
a racing process which tries to open such mangled tty, which was not
closed yet, the process will crash in hvc_open as tty->driver_data is
NULL.

All this happens because close wants to know whether open failed or not.
But ->open should not NULL this and other tty fields for ->close to be
happy. ->open should call tty_port_set_initialized(true) and close
should check by tty_port_initialized() instead. So do this properly in
this driver.

So this patch removes these from ->open:
* tty_port_tty_set(&hp->port, NULL). This happens on last close.
* tty->driver_data = NULL. Dtto.
* tty_port_put(&hp->port). This happens in shutdown and until now, this
  must have been causing a reference underflow, if I am not missing
  something.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Reported-and-tested-by: Raghavendra <rananta@codeaurora.org>
Link: https://lore.kernel.org/r/20200526145632.13879-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vt: keyboard: avoid signed integer overflow in k_ascii 2020-06-10T18:22:51+00:00 Dmitry Torokhov dmitry.torokhov@gmail.com 2020-05-25T23:27:40+00:00 9a17273f1efe47b0d773fef0a987ea28dafb92f2 commit b86dab054059b970111b5516ae548efaae5b3aae upstream. When k_ascii is invoked several times in a row there is a potential for signed integer overflow: UBSAN: Undefined behaviour in drivers/tty/vt/keyboard.c:888:19 signed integer overflow: 10 * 1111111111 cannot be represented in type 'int' CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.11 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xce/0x128 lib/dump_stack.c:118 ubsan_epilogue+0xe/0x30 lib/ubsan.c:154 handle_overflow+0xdc/0xf0 lib/ubsan.c:184 __ubsan_handle_mul_overflow+0x2a/0x40 lib/ubsan.c:205 k_ascii+0xbf/0xd0 drivers/tty/vt/keyboard.c:888 kbd_keycode drivers/tty/vt/keyboard.c:1477 [inline] kbd_event+0x888/0x3be0 drivers/tty/vt/keyboard.c:1495 While it can be worked around by using check_mul_overflow()/ check_add_overflow(), it is better to introduce a separate flag to signal that number pad is being used to compose a symbol, and change type of the accumulator from signed to unsigned, thus avoiding undefined behavior when it overflows. Reported-by: Kyungtae Kim <kt0755@gmail.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200525232740.GA262061@dtor-ws Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b86dab054059b970111b5516ae548efaae5b3aae upstream.

When k_ascii is invoked several times in a row there is a potential for
signed integer overflow:

UBSAN: Undefined behaviour in drivers/tty/vt/keyboard.c:888:19 signed integer overflow:
10 * 1111111111 cannot be represented in type 'int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.11 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xce/0x128 lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x30 lib/ubsan.c:154
 handle_overflow+0xdc/0xf0 lib/ubsan.c:184
 __ubsan_handle_mul_overflow+0x2a/0x40 lib/ubsan.c:205
 k_ascii+0xbf/0xd0 drivers/tty/vt/keyboard.c:888
 kbd_keycode drivers/tty/vt/keyboard.c:1477 [inline]
 kbd_event+0x888/0x3be0 drivers/tty/vt/keyboard.c:1495

While it can be worked around by using check_mul_overflow()/
check_add_overflow(), it is better to introduce a separate flag to
signal that number pad is being used to compose a symbol, and
change type of the accumulator from signed to unsigned, thus
avoiding undefined behavior when it overflows.

Reported-by: Kyungtae Kim <kt0755@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200525232740.GA262061@dtor-ws
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: 8250: Enable 16550A variants by default on non-x86 2020-06-10T18:22:51+00:00 Josh Triplett josh@joshtriplett.org 2020-05-26T16:13:57+00:00 be43f8dba56d8a85617bcf14ebad77563cde1bc2 commit 15a3f03d5ec0118f1e5db3fc1018686e72744e37 upstream. Some embedded devices still use these serial ports; make sure they're still enabled by default on architectures more likely to have them, to avoid rendering someone's console unavailable. Reported-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reported-by: Maxim Kochetkov <fido_max@inbox.ru> Fixes: dc56ecb81a0a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants") Cc: stable <stable@vger.kernel.org> Signed-off-by: Josh Triplett <josh@joshtriplett.org> Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 15a3f03d5ec0118f1e5db3fc1018686e72744e37 upstream.

Some embedded devices still use these serial ports; make sure they're
still enabled by default on architectures more likely to have them, to
avoid rendering someone's console unavailable.

Reported-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reported-by: Maxim Kochetkov <fido_max@inbox.ru>
Fixes: dc56ecb81a0a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: add missing spin_lock_init for SiFive serial console 2020-05-27T15:48:24+00:00 Sagar Shrikant Kadam sagar.kadam@sifive.com 2020-05-09T10:24:12+00:00 fdf302db828f889213ccba029a07833d55f41ce6 commit 17b4efdf4e4867079012a48ca10d965fe9d68822 upstream. An uninitialised spin lock for sifive serial console raises a bad magic spin_lock error as reported and discussed here [1]. Initialising the spin lock resolves the issue. The fix is tested on HiFive Unleashed A00 board with Linux 5.7-rc4 and OpenSBI v0.7 [1] https://lore.kernel.org/linux-riscv/b9fe49483a903f404e7acc15a6efbef756db28ae.camel@wdc.com Fixes: 45c054d0815b ("tty: serial: add driver for the SiFive UART") Reported-by: Atish Patra <Atish.Patra@wdc.com> Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@sifive.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1589019852-21505-2-git-send-email-sagar.kadam@sifive.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 17b4efdf4e4867079012a48ca10d965fe9d68822 upstream.

An uninitialised spin lock for sifive serial console raises a bad
magic spin_lock error as reported and discussed here [1].
Initialising the spin lock resolves the issue.

The fix is tested on HiFive Unleashed A00 board with Linux 5.7-rc4
and OpenSBI v0.7

[1] https://lore.kernel.org/linux-riscv/b9fe49483a903f404e7acc15a6efbef756db28ae.camel@wdc.com

Fixes: 45c054d0815b ("tty: serial: add driver for the SiFive UART")
Reported-by: Atish Patra <Atish.Patra@wdc.com>
Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1589019852-21505-2-git-send-email-sagar.kadam@sifive.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: xilinx_uartps: Fix missing id assignment to the console 2020-05-14T05:59:13+00:00 Shubhrajyoti Datta shubhrajyoti.datta@xilinx.com 2020-05-04T14:27:28+00:00 89a92b314b72f76a1ab30583bf872bcecf9c81f1 [ Upstream commit 2ae11c46d5fdc46cb396e35911c713d271056d35 ] When serial console has been assigned to ttyPS1 (which is serial1 alias) console index is not updated property and pointing to index -1 (statically initialized) which ends up in situation where nothing has been printed on the port. The commit 18cc7ac8a28e ("Revert "serial: uartps: Register own uart console and driver structures"") didn't contain this line which was removed by accident. Fixes: 18cc7ac8a28e ("Revert "serial: uartps: Register own uart console and driver structures"") Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Link: https://lore.kernel.org/r/ed3111533ef5bd342ee5ec504812240b870f0853.1588602446.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2ae11c46d5fdc46cb396e35911c713d271056d35 ]

When serial console has been assigned to ttyPS1 (which is serial1 alias)
console index is not updated property and pointing to index -1 (statically
initialized) which ends up in situation where nothing has been printed on
the port.

The commit 18cc7ac8a28e ("Revert "serial: uartps: Register own uart console
and driver structures"") didn't contain this line which was removed by
accident.

Fixes: 18cc7ac8a28e ("Revert "serial: uartps: Register own uart console and driver structures"")
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/ed3111533ef5bd342ee5ec504812240b870f0853.1588602446.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
vt: fix unicode console freeing with a common interface 2020-05-14T05:59:13+00:00 Nicolas Pitre nico@fluxnic.net 2020-05-02T15:01:07+00:00 cce929e49a31360815a74c3f280c6c13c3c8c5c8 [ Upstream commit 57d38f26d81e4275748b69372f31df545dcd9b71 ] By directly using kfree() in different places we risk missing one if it is switched to using vfree(), especially if the corresponding vmalloc() is hidden away within a common abstraction. Oh wait, that's exactly what happened here. So let's fix this by creating a common abstraction for the free case as well. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Reported-by: syzbot+0bfda3ade1ee9288a1be@syzkaller.appspotmail.com Fixes: 9a98e7a80f95 ("vt: don't use kmalloc() for the unicode screen buffer") Cc: <stable@vger.kernel.org> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2005021043110.2671@knanqh.ubzr Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 57d38f26d81e4275748b69372f31df545dcd9b71 ]

By directly using kfree() in different places we risk missing one if
it is switched to using vfree(), especially if the corresponding
vmalloc() is hidden away within a common abstraction.

Oh wait, that's exactly what happened here.

So let's fix this by creating a common abstraction for the free case
as well.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Reported-by: syzbot+0bfda3ade1ee9288a1be@syzkaller.appspotmail.com
Fixes: 9a98e7a80f95 ("vt: don't use kmalloc() for the unicode screen buffer")
Cc: <stable@vger.kernel.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2005021043110.2671@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Revert "serial: uartps: Register own uart console and driver structures" 2020-04-29T14:34:57+00:00 Michal Simek michal.simek@xilinx.com 2020-04-03T09:24:36+00:00 29772eb399a39a5de4c7528683b2be58e0e20f8f commit 18cc7ac8a28e28cd005c2475f52576cfe10cabfb upstream. This reverts commit 024ca329bfb9a948f76eaff3243e21b7e70182f2. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1ee35667e36a8efddee381df5fe495ad65f4d15c.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 18cc7ac8a28e28cd005c2475f52576cfe10cabfb upstream.

This reverts commit 024ca329bfb9a948f76eaff3243e21b7e70182f2.

As Johan says, this driver needs a lot more work and these changes are
only going in the wrong direction:
  https://lkml.kernel.org/r/20190523091839.GC568@localhost

Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1ee35667e36a8efddee381df5fe495ad65f4d15c.1585905873.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "serial: uartps: Move Port ID to device data structure" 2020-04-29T14:34:57+00:00 Michal Simek michal.simek@xilinx.com 2020-04-03T09:24:35+00:00 ec37770e030a75e00e759b6c7100499eaa30581d commit 492cc08bc16c44e2e587362ada3f6269dee2be22 upstream. This reverts commit bed25ac0e2b6ab8f9aed2d20bc9c3a2037311800. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/eb0ec98fecdca9b79c1a3ac0c30c668b6973b193.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 492cc08bc16c44e2e587362ada3f6269dee2be22 upstream.

This reverts commit bed25ac0e2b6ab8f9aed2d20bc9c3a2037311800.

As Johan says, this driver needs a lot more work and these changes are
only going in the wrong direction:
  https://lkml.kernel.org/r/20190523091839.GC568@localhost

Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/eb0ec98fecdca9b79c1a3ac0c30c668b6973b193.1585905873.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "serial: uartps: Change uart ID port allocation" 2020-04-29T14:34:57+00:00 Michal Simek michal.simek@xilinx.com 2020-04-03T09:24:34+00:00 f1a2c6402d088e36344d57207ede0893901c6a99 commit 72d68197281e2ad313960504d10b0c41ff87fd55 upstream. This reverts commit ae1cca3fa3478be92948dbbcd722390272032ade. With setting up NR_PORTS to 16 to be able to use serial2 and higher aliases and don't loose functionality which was intended by these changes. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/a94931b65ce0089f76fb1fe6b446a08731bff754.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 72d68197281e2ad313960504d10b0c41ff87fd55 upstream.

This reverts commit ae1cca3fa3478be92948dbbcd722390272032ade.

With setting up NR_PORTS to 16 to be able to use serial2 and higher
aliases and don't loose functionality which was intended by these changes.

As Johan says, this driver needs a lot more work and these changes are
only going in the wrong direction:
  https://lkml.kernel.org/r/20190523091839.GC568@localhost

Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/a94931b65ce0089f76fb1fe6b446a08731bff754.1585905873.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES" 2020-04-29T14:34:57+00:00 Michal Simek michal.simek@xilinx.com 2020-04-03T09:24:33+00:00 cd7189b8647c91be26722f5c5b8040a9e1b09b9a commit 91c9dfa25c7f95b543c280e0edf1fd8de6e90985 upstream. This reverts commit 2088cfd882d0403609bdf426e9b24372fe1b8337. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/dac3898e3e32d963f357fb436ac9a7ac3cbcf933.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 91c9dfa25c7f95b543c280e0edf1fd8de6e90985 upstream.

This reverts commit 2088cfd882d0403609bdf426e9b24372fe1b8337.

As Johan says, this driver needs a lot more work and these changes are
only going in the wrong direction:
  https://lkml.kernel.org/r/20190523091839.GC568@localhost

Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/dac3898e3e32d963f357fb436ac9a7ac3cbcf933.1585905873.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>