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2020-06-30Revert "tty: hvc: Fix data abort due to race in hvc_open"Greg Kroah-Hartman1-14/+2
commit cf9c94456ebafc6d75a834e58dfdc8ae71a3acbc upstream. This reverts commit e2bd1dcbe1aa34ff5570b3427c530e4332ecf0fe. In discussion on the mailing list, it has been determined that this is not the correct type of fix for this issue. Revert it so that we can do this correctly. Reported-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20200428032601.22127-1-rananta@codeaurora.org Cc: Raghavendra Rao Ananta <rananta@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-24tty: n_gsm: Fix bogus i++ in gsm_data_kickGregory CLEMENT1-11/+3
[ Upstream commit 4dd31f1ffec6c370c3c2e0c605628bf5e16d5c46 ] When submitting the previous fix "tty: n_gsm: Fix waking up upper tty layer when room available". It was suggested to switch from a while to a for loop, but when doing it, there was a remaining bogus i++. This patch removes this i++ and also reorganizes the code making it more compact. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20200518084517.2173242-3-gregory.clement@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24tty: n_gsm: Fix waking up upper tty layer when room availableGregory CLEMENT1-4/+22
[ Upstream commit 01dbb362f0a114fbce19c8abe4cd6f4710e934d5 ] Warn the upper layer when n_gms is ready to receive data again. Without this the associated virtual tty remains blocked indefinitely. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20200512115323.1447922-4-gregory.clement@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24tty: n_gsm: Fix SOF skippingGregory CLEMENT1-7/+1
[ Upstream commit 84d6f81c1fb58b56eba81ff0a36cf31946064b40 ] For at least some modems like the TELIT LE910, skipping SOF makes transfers blocking indefinitely after a short amount of data transferred. Given the small improvement provided by skipping the SOF (just one byte on about 100 bytes), it seems better to completely remove this "feature" than make it optional. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20200512115323.1447922-3-gregory.clement@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24serial: amba-pl011: Make sure we initialize the port.lock spinlockJohn Stultz1-0/+1
[ Upstream commit 8508f4cba308f785b2fd4b8c38849c117b407297 ] Valentine reported seeing: [ 3.626638] INFO: trying to register non-static key. [ 3.626639] the code is fine but needs lockdep annotation. [ 3.626640] turning off the locking correctness validator. [ 3.626644] CPU: 7 PID: 51 Comm: kworker/7:1 Not tainted 5.7.0-rc2-00115-g8c2e9790f196 #116 [ 3.626646] Hardware name: HiKey960 (DT) [ 3.626656] Workqueue: events deferred_probe_work_func [ 3.632476] sd 0:0:0:0: [sda] Optimal transfer size 8192 bytes not a multiple of physical block size (16384 bytes) [ 3.640220] Call trace: [ 3.640225] dump_backtrace+0x0/0x1b8 [ 3.640227] show_stack+0x20/0x30 [ 3.640230] dump_stack+0xec/0x158 [ 3.640234] register_lock_class+0x598/0x5c0 [ 3.640235] __lock_acquire+0x80/0x16c0 [ 3.640236] lock_acquire+0xf4/0x4a0 [ 3.640241] _raw_spin_lock_irqsave+0x70/0xa8 [ 3.640245] uart_add_one_port+0x388/0x4b8 [ 3.640248] pl011_register_port+0x70/0xf0 [ 3.640250] pl011_probe+0x184/0x1b8 [ 3.640254] amba_probe+0xdc/0x180 [ 3.640256] really_probe+0xe0/0x338 [ 3.640257] driver_probe_device+0x60/0xf8 [ 3.640259] __device_attach_driver+0x8c/0xd0 [ 3.640260] bus_for_each_drv+0x84/0xd8 [ 3.640261] __device_attach+0xe4/0x140 [ 3.640263] device_initial_probe+0x1c/0x28 [ 3.640265] bus_probe_device+0xa4/0xb0 [ 3.640266] deferred_probe_work_func+0x7c/0xb8 [ 3.640269] process_one_work+0x2c0/0x768 [ 3.640271] worker_thread+0x4c/0x498 [ 3.640272] kthread+0x14c/0x158 [ 3.640275] ret_from_fork+0x10/0x1c Which seems to be due to the fact that after allocating the uap structure, nothing initializes the spinlock. Its a little confusing, as uart_port_spin_lock_init() is one place where the lock is supposed to be initialized, but it has an exception for the case where the port is a console. This makes it seem like a deeper fix is needed to properly register the console, but I'm not sure what that entails, and Andy suggested that this approach is less invasive. Thus, this patch resolves the issue by initializing the spinlock in the driver, and resolves the resulting warning. Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Jiri Slaby <jslaby@suse.com> Cc: linux-serial@vger.kernel.org Reported-by: Valentin Schneider <valentin.schneider@arm.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Reviewed-and-tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lore.kernel.org/r/20200428184050.6501-1-john.stultz@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24tty: hvc: Fix data abort due to race in hvc_openRaghavendra Rao Ananta1-2/+14
[ Upstream commit e2bd1dcbe1aa34ff5570b3427c530e4332ecf0fe ] Potentially, hvc_open() can be called in parallel when two tasks calls open() on /dev/hvcX. In such a scenario, if the hp->ops->notifier_add() callback in the function fails, where it sets the tty->driver_data to NULL, the parallel hvc_open() can see this NULL and cause a memory abort. Hence, serialize hvc_open and check if tty->private_data is NULL before proceeding ahead. The issue can be easily reproduced by launching two tasks simultaneously that does nothing but open() and close() on /dev/hvcX. For example: $ ./simple_open_close /dev/hvc0 & ./simple_open_close /dev/hvc0 & Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org> Link: https://lore.kernel.org/r/20200428032601.22127-1-rananta@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24serial: 8250: Fix max baud limit in generic 8250 portSerge Semin1-1/+3
[ Upstream commit 7b668c064ec33f3d687c3a413d05e355172e6c92 ] Standard 8250 UART ports are designed in a way so they can communicate with baud rates up to 1/16 of a reference frequency. It's expected from most of the currently supported UART controllers. That's why the former version of serial8250_get_baud_rate() method called uart_get_baud_rate() with min and max baud rates passed as (port->uartclk / 16 / UART_DIV_MAX) and ((port->uartclk + tolerance) / 16) respectively. Doing otherwise, like it was suggested in commit ("serial: 8250_mtk: support big baud rate."), caused acceptance of bauds, which was higher than the normal UART controllers actually supported. As a result if some user-space program requested to set a baud greater than (uartclk / 16) it would have been permitted without truncation, but then serial8250_get_divisor(baud) (which calls uart_get_divisor() to get the reference clock divisor) would have returned a zero divisor. Setting zero divisor will cause an unpredictable effect varying from chip to chip. In case of DW APB UART the communications just stop. Lets fix this problem by getting back the limitation of (uartclk + tolerance) / 16 maximum baud supported by the generic 8250 port. Mediatek 8250 UART ports driver developer shouldn't have touched it in the first place notably seeing he already provided a custom version of set_termios() callback in that glue-driver which took into account the extended baud rate values and accordingly updated the standard and vendor-specific divisor latch registers anyway. Fixes: 81bb549fdf14 ("serial: 8250_mtk: support big baud rate.") Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Long Cheng <long.cheng@mediatek.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: linux-mips@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mediatek@lists.infradead.org Link: https://lore.kernel.org/r/20200506233136.11842-2-Sergey.Semin@baikalelectronics.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-22serial: 8250: Avoid error message on reprobeLukas Wunner1-4/+10
commit e0a851fe6b9b619527bd928aa93caaddd003f70c upstream. If the call to uart_add_one_port() in serial8250_register_8250_port() fails, a half-initialized entry in the serial_8250ports[] array is left behind. A subsequent reprobe of the same serial port causes that entry to be reused. Because uart->port.dev is set, uart_remove_one_port() is called for the half-initialized entry and bails out with an error message: bcm2835-aux-uart 3f215040.serial: Removing wrong port: (null) != (ptrval) The same happens on failure of mctrl_gpio_init() since commit 4a96895f74c9 ("tty/serial/8250: use mctrl_gpio helpers"). Fix by zeroing the uart->port.dev pointer in the probe error path. The bug was introduced in v2.6.10 by historical commit befff6f5bf5f ("[SERIAL] Add new port registration/unregistration functions."): https://git.kernel.org/tglx/history/c/befff6f5bf5f The commit added an unconditional call to uart_remove_one_port() in serial8250_register_port(). In v3.7, commit 835d844d1a28 ("8250_pnp: do pnp probe before legacy probe") made that call conditional on uart->port.dev which allows me to fix the issue by zeroing that pointer in the error path. Thus, the present commit will fix the problem as far back as v3.7 whereas still older versions need to also cherry-pick 835d844d1a28. Fixes: 835d844d1a28 ("8250_pnp: do pnp probe before legacy probe") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v2.6.10 Cc: stable@vger.kernel.org # v2.6.10: 835d844d1a28: 8250_pnp: do pnp probe before legacy Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/b4a072013ee1a1d13ee06b4325afb19bda57ca1b.1589285873.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-22serial: 8250_pci: Move Pericom IDs to pci_ids.hKai-Heng Feng1-6/+0
[ Upstream commit 62a7f3009a460001eb46984395280dd900bc4ef4 ] Move the IDs to pci_ids.h so it can be used by next patch. Link: https://lore.kernel.org/r/20200508065343.32751-1-kai.heng.feng@canonical.com Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-22kgdboc: Use a platform device to handle tty drivers showing up lateDouglas Anderson1-25/+101
[ Upstream commit 68e55f61c13842baf825958129698c5371db432c ] If you build CONFIG_KGDB_SERIAL_CONSOLE into the kernel then you should be able to have KGDB init itself at bootup by specifying the "kgdboc=..." kernel command line parameter. This has worked OK for me for many years, but on a new device I switched to it stopped working. The problem is that on this new device the serial driver gets its probe deferred. Now when kgdb initializes it can't find the tty driver and when it gives up it never tries again. We could try to find ways to move up the initialization of the serial driver and such a thing might be worthwhile, but it's nice to be robust against serial drivers that load late. We could move kgdb to init itself later but that penalizes our ability to debug early boot code on systems where the driver inits early. We could roll our own system of detecting when new tty drivers get loaded and then use that to figure out when kgdb can init, but that's ugly. Instead, let's jump on the -EPROBE_DEFER bandwagon. We'll create a singleton instance of a "kgdboc" platform device. If we can't find our tty device when the singleton "kgdboc" probes we'll return -EPROBE_DEFER which means that the system will call us back later to try again when the tty device might be there. We won't fully transition all of the kgdboc to a platform device because early kgdb initialization (via the "ekgdboc" kernel command line parameter) still runs before the platform device has been created. The kgdb platform device is merely used as a convenient way to hook into the system's normal probe deferral mechanisms. As part of this, we'll ever-so-slightly change how the "kgdboc=..." kernel command line parameter works. Previously if you booted up and kgdb couldn't find the tty driver then later reading '/sys/module/kgdboc/parameters/kgdboc' would return a blank string. Now kgdb will keep track of the string that came as part of the command line and give it back to you. It's expected that this should be an OK change. Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Link: https://lore.kernel.org/r/20200507130644.v4.3.I4a493cfb0f9f740ce8fd2ab58e62dc92d18fed30@changeid [daniel.thompson@linaro.org: Make config_mutex static] Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-10tty: hvc_console, fix crashes on parallel open/closeJiri Slaby1-15/+8
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>
2020-06-10vt: keyboard: avoid signed integer overflow in k_asciiDmitry Torokhov1-10/+16
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>
2020-05-27tty: serial: add missing spin_lock_init for SiFive serial consoleSagar Shrikant Kadam1-0/+1
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>
2020-05-14tty: xilinx_uartps: Fix missing id assignment to the consoleShubhrajyoti Datta1-0/+1
[ 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>
2020-05-14vt: fix unicode console freeing with a common interfaceNicolas Pitre1-2/+7
[ 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>
2020-04-29Revert "serial: uartps: Register own uart console and driver structures"Michal Simek1-55/+40
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>
2020-04-29Revert "serial: uartps: Move Port ID to device data structure"Michal Simek1-11/+9
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>
2020-04-29Revert "serial: uartps: Change uart ID port allocation"Michal Simek1-98/+13
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>
2020-04-29Revert "serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES"Michal Simek1-4/+2
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>
2020-04-29Revert "serial: uartps: Fix error path when alloc failed"Michal Simek1-4/+2
commit b6fd2dbbd649b89a3998528994665ded1e3fbf7f upstream. This reverts commit 32cf21ac4edd6c0d5b9614368a83bcdc68acb031. 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/46cd7f039db847c08baa6508edd7854f7c8ff80f.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29Revert "serial: uartps: Use the same dynamic major number for all ports"Michal Simek1-3/+2
commit 8da1a3940da4b0e82848ec29b835486890bc9232 upstream. This reverts commit ab262666018de6f4e206b021386b93ed0c164316. 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/14a565fc1e14a5ec6cc6a6710deb878ae8305f22.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29Revert "serial: uartps: Fix uartps_major handling"Michal Simek1-7/+1
commit 2e01911b7cf7aa07a304a809eca1b11a4bd35859 upstream. This reverts commit 5e9bd2d70ae7c00a95a22994abf1eef728649e64. 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/310999ab5342f788a7bc1b0e68294d4f052cad07.1585905873.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29serial: sh-sci: Make sure status register SCxSR is read in correct sequenceKazuhiro Fujita1-3/+10
commit 3dc4db3662366306e54ddcbda4804acb1258e4ba upstream. For SCIF and HSCIF interfaces the SCxSR register holds the status of data that is to be read next from SCxRDR register, But where as for SCIFA and SCIFB interfaces SCxSR register holds status of data that is previously read from SCxRDR register. This patch makes sure the status register is read depending on the port types so that errors are caught accordingly. Cc: <stable@vger.kernel.org> Signed-off-by: Kazuhiro Fujita <kazuhiro.fujita.jg@renesas.com> Signed-off-by: Hao Bui <hao.bui.yg@renesas.com> Signed-off-by: KAZUMI HARADA <kazumi.harada.rh@renesas.com> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/1585333048-31828-1-git-send-email-kazuhiro.fujita.jg@renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29vt: don't use kmalloc() for the unicode screen bufferNicolas Pitre1-2/+3
commit 9a98e7a80f95378c9ee0c644705e3b5aa54745f1 upstream. Even if the actual screen size is bounded in vc_do_resize(), the unicode buffer is still a little more than twice the size of the glyph buffer and may exceed MAX_ORDER down the kmalloc() path. This can be triggered from user space. Since there is no point having a physically contiguous buffer here, let's avoid the above issue as well as reducing pressure on high order allocations by using vmalloc() instead. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Cc: <stable@vger.kernel.org> Acked-by: Sam Ravnborg <sam@ravnborg.org> Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2003282214210.2671@knanqh.ubzr Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29vt: don't hardcode the mem allocation upper boundNicolas Pitre1-1/+1
commit 2717769e204e83e65b8819c5e2ef3e5b6639b270 upstream. The code in vc_do_resize() bounds the memory allocation size to avoid exceeding MAX_ORDER down the kzalloc() call chain and generating a runtime warning triggerable from user space. However, not only is it unwise to use a literal value here, but MAX_ORDER may also be configurable based on CONFIG_FORCE_MAX_ZONEORDER. Let's use KMALLOC_MAX_SIZE instead. Note that prior commit bb1107f7c605 ("mm, slab: make sure that KMALLOC_MAX_SIZE will fit into MAX_ORDER") the KMALLOC_MAX_SIZE value could not be relied upon. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Cc: <stable@vger.kernel.org> # v4.10+ Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2003281702410.2671@knanqh.ubzr Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29tty: rocket, avoid OOB accessJiri Slaby1-11/+14
commit 7127d24372bf23675a36edc64d092dc7fd92ebe8 upstream. init_r_port can access pc104 array out of bounds. pc104 is a 2D array defined to have 4 members. Each member has 8 submembers. * we can have more than 4 (PCI) boards, i.e. [board] can be OOB * line is not modulo-ed by anything, so the first line on the second board can be 4, on the 3rd 12 or alike (depending on previously registered boards). It's zero only on the first line of the first board. So even [line] can be OOB, quite soon (with the 2nd registered board already). This code is broken for ages, so just avoid the OOB accesses and don't try to fix it as we would need to find out the correct line number. Use the default: RS232, if we are out. Generally, if anyone needs to set the interface types, a module parameter is past the last thing that should be used for this purpose. The parameters' description says it's for ISA cards anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@vger.kernel.org> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Link: https://lore.kernel.org/r/20200417105959.15201-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29tty: hvc: fix buffer overflow during hvc_alloc().Andrew Melnychenko1-9/+14
commit 9a9fc42b86c06120744555fea43fdcabe297c656 upstream. If there is a lot(more then 16) of virtio-console devices or virtio_console module is reloaded - buffers 'vtermnos' and 'cons_ops' are overflowed. In older kernels it overruns spinlock which leads to kernel freezing: https://bugzilla.redhat.com/show_bug.cgi?id=1786239 To reproduce the issue, you can try simple script that loads/unloads module. Something like this: while [ 1 ] do modprobe virtio_console sleep 2 modprobe -r virtio_console sleep 2 done Description of problem: Guest get 'Call Trace' when loading module "virtio_console" and unloading it frequently - clearly reproduced on kernel-4.18.0: [ 81.498208] ------------[ cut here ]------------ [ 81.499263] pvqspinlock: lock 0xffffffff92080020 has corrupted value 0xc0774ca0! [ 81.501000] WARNING: CPU: 0 PID: 785 at kernel/locking/qspinlock_paravirt.h:500 __pv_queued_spin_unlock_slowpath+0xc0/0xd0 [ 81.503173] Modules linked in: virtio_console fuse xt_CHECKSUM ipt_MASQUERADE xt_conntrack ipt_REJECT nft_counter nf_nat_tftp nft_objref nf_conntrack_tftp tun bridge stp llc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nf_tables_set nft_chain_nat_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 nft_chain_route_ipv6 nft_chain_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack nft_chain_route_ipv4 ip6_tables nft_compat ip_set nf_tables nfnetlink sunrpc bochs_drm drm_vram_helper ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm i2c_piix4 pcspkr crct10dif_pclmul crc32_pclmul joydev ghash_clmulni_intel ip_tables xfs libcrc32c sd_mod sg ata_generic ata_piix virtio_net libata crc32c_intel net_failover failover serio_raw virtio_scsi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: virtio_console] [ 81.517019] CPU: 0 PID: 785 Comm: kworker/0:2 Kdump: loaded Not tainted 4.18.0-167.el8.x86_64 #1 [ 81.518639] Hardware name: Red Hat KVM, BIOS 1.12.0-5.scrmod+el8.2.0+5159+d8aa4d83 04/01/2014 [ 81.520205] Workqueue: events control_work_handler [virtio_console] [ 81.521354] RIP: 0010:__pv_queued_spin_unlock_slowpath+0xc0/0xd0 [ 81.522450] Code: 07 00 48 63 7a 10 e8 bf 64 f5 ff 66 90 c3 8b 05 e6 cf d6 01 85 c0 74 01 c3 8b 17 48 89 fe 48 c7 c7 38 4b 29 91 e8 3a 6c fa ff <0f> 0b c3 0f 0b 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 [ 81.525830] RSP: 0018:ffffb51a01ffbd70 EFLAGS: 00010282 [ 81.526798] RAX: 0000000000000000 RBX: 0000000000000010 RCX: 0000000000000000 [ 81.528110] RDX: ffff9e66f1826480 RSI: ffff9e66f1816a08 RDI: ffff9e66f1816a08 [ 81.529437] RBP: ffffffff9153ff10 R08: 000000000000026c R09: 0000000000000053 [ 81.530732] R10: 0000000000000000 R11: ffffb51a01ffbc18 R12: ffff9e66cd682200 [ 81.532133] R13: ffffffff9153ff10 R14: ffff9e6685569500 R15: ffff9e66cd682000 [ 81.533442] FS: 0000000000000000(0000) GS:ffff9e66f1800000(0000) knlGS:0000000000000000 [ 81.534914] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 81.535971] CR2: 00005624c55b14d0 CR3: 00000003a023c000 CR4: 00000000003406f0 [ 81.537283] Call Trace: [ 81.537763] __raw_callee_save___pv_queued_spin_unlock_slowpath+0x11/0x20 [ 81.539011] .slowpath+0x9/0xe [ 81.539585] hvc_alloc+0x25e/0x300 [ 81.540237] init_port_console+0x28/0x100 [virtio_console] [ 81.541251] handle_control_message.constprop.27+0x1c4/0x310 [virtio_console] [ 81.542546] control_work_handler+0x70/0x10c [virtio_console] [ 81.543601] process_one_work+0x1a7/0x3b0 [ 81.544356] worker_thread+0x30/0x390 [ 81.545025] ? create_worker+0x1a0/0x1a0 [ 81.545749] kthread+0x112/0x130 [ 81.546358] ? kthread_flush_work_fn+0x10/0x10 [ 81.547183] ret_from_fork+0x22/0x40 [ 81.547842] ---[ end trace aa97649bd16c8655 ]--- [ 83.546539] general protection fault: 0000 [#1] SMP NOPTI [ 83.547422] CPU: 5 PID: 3225 Comm: modprobe Kdump: loaded Tainted: G W --------- - - 4.18.0-167.el8.x86_64 #1 [ 83.549191] Hardware name: Red Hat KVM, BIOS 1.12.0-5.scrmod+el8.2.0+5159+d8aa4d83 04/01/2014 [ 83.550544] RIP: 0010:__pv_queued_spin_lock_slowpath+0x19a/0x2a0 [ 83.551504] Code: c4 c1 ea 12 41 be 01 00 00 00 4c 8d 6d 14 41 83 e4 03 8d 42 ff 49 c1 e4 05 48 98 49 81 c4 40 a5 02 00 4c 03 24 c5 60 48 34 91 <49> 89 2c 24 b8 00 80 00 00 eb 15 84 c0 75 0a 41 0f b6 54 24 14 84 [ 83.554449] RSP: 0018:ffffb51a0323fdb0 EFLAGS: 00010202 [ 83.555290] RAX: 000000000000301c RBX: ffffffff92080020 RCX: 0000000000000001 [ 83.556426] RDX: 000000000000301d RSI: 0000000000000000 RDI: 0000000000000000 [ 83.557556] RBP: ffff9e66f196a540 R08: 000000000000028a R09: ffff9e66d2757788 [ 83.558688] R10: 0000000000000000 R11: 0000000000000000 R12: 646e61725f770b07 [ 83.559821] R13: ffff9e66f196a554 R14: 0000000000000001 R15: 0000000000180000 [ 83.560958] FS: 00007fd5032e8740(0000) GS:ffff9e66f1940000(0000) knlGS:0000000000000000 [ 83.562233] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 83.563149] CR2: 00007fd5022b0da0 CR3: 000000038c334000 CR4: 00000000003406e0 Signed-off-by: Andrew Melnychenko <andrew@daynix.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200414191503.3471783-1-andrew@daynix.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29tty: serial: owl: add "much needed" clk_prepare_enable()Amit Singh Tomar1-0/+7
commit abf42d2f333b21bf8d33b2fbb8a85fa62037ac01 upstream. commit 8ba92cf59335 ("arm64: dts: actions: s700: Add Clock Management Unit") breaks the UART on Cubieboard7-lite (based on S700 SoC), This is due to the fact that generic clk routine clk_disable_unused() disables the gate clks, and that in turns disables OWL UART (but UART driver never enables it). To prove this theory, Andre suggested to use "clk_ignore_unused" in kernel commnd line and it worked (Kernel happily lands into RAMFS world :)). This commit fix this up by adding clk_prepare_enable(). Fixes: 8ba92cf59335 ("arm64: dts: actions: s700: Add Clock Management Unit") Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1587067917-1400-1-git-send-email-amittomer25@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-23tty: evh_bytechan: Fix out of bounds accessesStephen Rothwell1-3/+18
commit 3670664b5da555a2a481449b3baafff113b0ac35 upstream. ev_byte_channel_send() assumes that its third argument is a 16 byte array. Some places where it is called it may not be (or we can't easily tell if it is). Newer compilers have started producing warnings about this, so make sure we actually pass a 16 byte array. There may be more elegant solutions to this, but the driver is quite old and hasn't been updated in many years. The warnings (from a powerpc allyesconfig build) are: In file included from include/linux/byteorder/big_endian.h:5, from arch/powerpc/include/uapi/asm/byteorder.h:14, from include/asm-generic/bitops/le.h:6, from arch/powerpc/include/asm/bitops.h:250, from include/linux/bitops.h:29, from include/linux/kernel.h:12, from include/asm-generic/bug.h:19, from arch/powerpc/include/asm/bug.h:109, from include/linux/bug.h:5, from include/linux/mmdebug.h:5, from include/linux/gfp.h:5, from include/linux/slab.h:15, from drivers/tty/ehv_bytechan.c:24: drivers/tty/ehv_bytechan.c: In function ‘ehv_bc_udbg_putc’: arch/powerpc/include/asm/epapr_hcalls.h:298:20: warning: array subscript 1 is outside array bounds of ‘const char[1]’ [-Warray-bounds] 298 | r6 = be32_to_cpu(p[1]); include/uapi/linux/byteorder/big_endian.h:40:51: note: in definition of macro ‘__be32_to_cpu’ 40 | #define __be32_to_cpu(x) ((__force __u32)(__be32)(x)) | ^ arch/powerpc/include/asm/epapr_hcalls.h:298:7: note: in expansion of macro ‘be32_to_cpu’ 298 | r6 = be32_to_cpu(p[1]); | ^~~~~~~~~~~ drivers/tty/ehv_bytechan.c:166:13: note: while referencing ‘data’ 166 | static void ehv_bc_udbg_putc(char c) | ^~~~~~~~~~~~~~~~ Fixes: dcd83aaff1c8 ("tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> [mpe: Trim warnings from change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200109183912.5fcb52aa@canb.auug.org.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vt: vt_ioctl: fix use-after-free in vt_in_use()Eric Biggers1-4/+12
commit 7cf64b18b0b96e751178b8d0505d8466ff5a448f upstream. vt_in_use() dereferences console_driver->ttys[i] without proper locking. This is broken because the tty can be closed and freed concurrently. We could fix this by using 'READ_ONCE(console_driver->ttys[i]) != NULL' and skipping the check of tty_struct::count. But, looking at console_driver->ttys[i] isn't really appropriate anyway because even if it is NULL the tty can still be in the process of being closed. Instead, fix it by making vt_in_use() require console_lock() and check whether the vt is allocated and has port refcount > 1. This works since following the patch "vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console" the port refcount is incremented while the vt is open. Reproducer (very unreliable, but it worked for me after a few minutes): #include <fcntl.h> #include <linux/vt.h> int main() { int fd, nproc; struct vt_stat state; char ttyname[16]; fd = open("/dev/tty10", O_RDONLY); for (nproc = 1; nproc < 8; nproc *= 2) fork(); for (;;) { sprintf(ttyname, "/dev/tty%d", rand() % 8); close(open(ttyname, O_RDONLY)); ioctl(fd, VT_GETSTATE, &state); } } KASAN report: BUG: KASAN: use-after-free in vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline] BUG: KASAN: use-after-free in vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657 Read of size 4 at addr ffff888065722468 by task syz-vt2/132 CPU: 0 PID: 132 Comm: syz-vt2 Not tainted 5.6.0-rc5-00130-g089b6d3654916 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014 Call Trace: [...] vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline] vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660 [...] Allocated by task 136: [...] kzalloc include/linux/slab.h:669 [inline] alloc_tty_struct+0x96/0x8a0 drivers/tty/tty_io.c:2982 tty_init_dev+0x23/0x350 drivers/tty/tty_io.c:1334 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline] tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035 [...] Freed by task 41: [...] kfree+0xbf/0x200 mm/slab.c:3757 free_tty_struct+0x8d/0xb0 drivers/tty/tty_io.c:177 release_one_tty+0x22d/0x2f0 drivers/tty/tty_io.c:1468 process_one_work+0x7f1/0x14b0 kernel/workqueue.c:2264 worker_thread+0x8b/0xc80 kernel/workqueue.c:2410 [...] Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle") Cc: <stable@vger.kernel.org> # v3.4+ Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20200322034305.210082-3-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual consoleEric Biggers2-9/+26
commit ca4463bf8438b403596edd0ec961ca0d4fbe0220 upstream. The VT_DISALLOCATE ioctl can free a virtual console while tty_release() is still running, causing a use-after-free in con_shutdown(). This occurs because VT_DISALLOCATE considers a virtual console's 'struct vc_data' to be unused as soon as the corresponding tty's refcount hits 0. But actually it may be still being closed. Fix this by making vc_data be reference-counted via the embedded 'struct tty_port'. A newly allocated virtual console has refcount 1. Opening it for the first time increments the refcount to 2. Closing it for the last time decrements the refcount (in tty_operations::cleanup() so that it happens late enough), as does VT_DISALLOCATE. Reproducer: #include <fcntl.h> #include <linux/vt.h> #include <sys/ioctl.h> #include <unistd.h> int main() { if (fork()) { for (;;) close(open("/dev/tty5", O_RDWR)); } else { int fd = open("/dev/tty10", O_RDWR); for (;;) ioctl(fd, VT_DISALLOCATE, 5); } } KASAN report: BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278 Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129 CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014 Call Trace: [...] con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278 release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514 tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629 tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789 [...] Allocated by task 129: [...] kzalloc include/linux/slab.h:669 [inline] vc_allocate drivers/tty/vt/vt.c:1085 [inline] vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066 con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline] tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline] tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035 [...] Freed by task 130: [...] kfree+0xbf/0x1e0 mm/slab.c:3757 vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline] vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660 [...] Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle") Cc: <stable@vger.kernel.org> # v3.4+ Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vt: vt_ioctl: remove unnecessary console allocation checksEric Biggers1-15/+1
commit 1aa6e058dd6cd04471b1f21298270014daf48ac9 upstream. The vc_cons_allocated() checks in vt_ioctl() and vt_compat_ioctl() are unnecessary because they can only be reached by calling ioctl() on an open tty, which implies the corresponding virtual console is allocated. And even if the virtual console *could* be freed concurrently, then these checks would be broken since they aren't done under console_lock, and the vc_data is dereferenced before them anyway. So, remove these unneeded checks to avoid confusion. Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20200224080326.295046-1-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vt: switch vt_dont_switch to boolJiri Slaby1-3/+3
commit f400991bf872debffb01c46da882dc97d7e3248e upstream. vt_dont_switch is pure boolean, no need for whole char. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200219073951.16151-6-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vt: ioctl, switch VT_IS_IN_USE and VT_BUSY to inlinesJiri Slaby1-7/+22
commit e587e8f17433ddb26954f0edf5b2f95c42155ae9 upstream. These two were macros. Switch them to static inlines, so that it's more understandable what they are doing. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200219073951.16151-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vt: selection, introduce vc_is_selJiri Slaby3-4/+10
commit dce05aa6eec977f1472abed95ccd71276b9a3864 upstream. Avoid global variables (namely sel_cons) by introducing vc_is_sel. It checks whether the parameter is the current selection console. This will help putting sel_cons to a struct later. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200219073951.16151-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02serial: sprd: Fix a dereference warningLanqing Liu1-2/+1
commit efc176929a3505a30c3993ddd393b40893649bd2 upstream. We should validate if the 'sup' is NULL or not before freeing DMA memory, to fix below warning. "drivers/tty/serial/sprd_serial.c:1141 sprd_remove() error: we previously assumed 'sup' could be null (see line 1132)" Fixes: f4487db58eb7 ("serial: sprd: Add DMA mode support") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Lanqing Liu <liuhhome@gmail.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/e2bd92691538e95b04a2c2a728f3292e1617018f.1584325957.git.liuhhome@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25tty: fix compat TIOCGSERIAL checking wrong function ptrEric Biggers1-1/+1
commit 6e622cd8bd888c7fa3ee2b7dfb3514ab53b21570 upstream. Commit 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start checking for the presence of the ->set_serial function pointer rather than ->get_serial. This appears to be a copy-and-paste error, since ->get_serial is the function pointer that is called as well as the pointer that is checked by the non-compat version of TIOCGSERIAL. Fix this by checking the correct function pointer. Fixes: 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") Cc: <stable@vger.kernel.org> # v4.20+ Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200224182044.234553-3-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25tty: fix compat TIOCGSERIAL leaking uninitialized memoryEric Biggers1-1/+3
commit 17329563a97df3ba474eca5037c1336e46e14ff8 upstream. Commit 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start copying a whole 'serial_struct32' to userspace rather than individual fields, but failed to initialize all padding and fields -- namely the hole after the 'iomem_reg_shift' field, and the 'reserved' field. Fix this by initializing the struct to zero. [v2: use sizeof, and convert the adjacent line for consistency.] Reported-by: syzbot+8da9175e28eadcb203ce@syzkaller.appspotmail.com Fixes: 77654350306a ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()") Cc: <stable@vger.kernel.org> # v4.20+ Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200224182044.234553-2-ebiggers@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12vt: selection, push sel_lock upJiri Slaby1-9/+7
commit e8c75a30a23c6ba63f4ef6895cbf41fd42f21aa2 upstream. sel_lock cannot nest in the console lock. Thanks to syzkaller, the kernel states firmly: > WARNING: possible circular locking dependency detected > 5.6.0-rc3-syzkaller #0 Not tainted > ------------------------------------------------------ > syz-executor.4/20336 is trying to acquire lock: > ffff8880a2e952a0 (&tty->termios_rwsem){++++}, at: tty_unthrottle+0x22/0x100 drivers/tty/tty_ioctl.c:136 > > but task is already holding lock: > ffffffff89462e70 (sel_lock){+.+.}, at: paste_selection+0x118/0x470 drivers/tty/vt/selection.c:374 > > which lock already depends on the new lock. > > the existing dependency chain (in reverse order) is: > > -> #2 (sel_lock){+.+.}: > mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118 > set_selection_kernel+0x3b8/0x18a0 drivers/tty/vt/selection.c:217 > set_selection_user+0x63/0x80 drivers/tty/vt/selection.c:181 > tioclinux+0x103/0x530 drivers/tty/vt/vt.c:3050 > vt_ioctl+0x3f1/0x3a30 drivers/tty/vt/vt_ioctl.c:364 This is ioctl(TIOCL_SETSEL). Locks held on the path: console_lock -> sel_lock > -> #1 (console_lock){+.+.}: > console_lock+0x46/0x70 kernel/printk/printk.c:2289 > con_flush_chars+0x50/0x650 drivers/tty/vt/vt.c:3223 > n_tty_write+0xeae/0x1200 drivers/tty/n_tty.c:2350 > do_tty_write drivers/tty/tty_io.c:962 [inline] > tty_write+0x5a1/0x950 drivers/tty/tty_io.c:1046 This is write(). Locks held on the path: termios_rwsem -> console_lock > -> #0 (&tty->termios_rwsem){++++}: > down_write+0x57/0x140 kernel/locking/rwsem.c:1534 > tty_unthrottle+0x22/0x100 drivers/tty/tty_ioctl.c:136 > mkiss_receive_buf+0x12aa/0x1340 drivers/net/hamradio/mkiss.c:902 > tty_ldisc_receive_buf+0x12f/0x170 drivers/tty/tty_buffer.c:465 > paste_selection+0x346/0x470 drivers/tty/vt/selection.c:389 > tioclinux+0x121/0x530 drivers/tty/vt/vt.c:3055 > vt_ioctl+0x3f1/0x3a30 drivers/tty/vt/vt_ioctl.c:364 This is ioctl(TIOCL_PASTESEL). Locks held on the path: sel_lock -> termios_rwsem > other info that might help us debug this: > > Chain exists of: > &tty->termios_rwsem --> console_lock --> sel_lock Clearly. From the above, we have: console_lock -> sel_lock sel_lock -> termios_rwsem termios_rwsem -> console_lock Fix this by reversing the console_lock -> sel_lock dependency in ioctl(TIOCL_SETSEL). First, lock sel_lock, then console_lock. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: syzbot+26183d9746e62da329b8@syzkaller.appspotmail.com Fixes: 07e6124a1a46 ("vt: selection, close sel_buffer race") Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200228115406.5735-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12vt: selection, push console lock downJiri Slaby2-3/+12
commit 4b70dd57a15d2f4685ac6e38056bad93e81e982f upstream. We need to nest the console lock in sel_lock, so we have to push it down a bit. Fortunately, the callers of set_selection_* just lock the console lock around the function call. So moving it down is easy. In the next patch, we switch the order. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Fixes: 07e6124a1a46 ("vt: selection, close sel_buffer race") Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200228115406.5735-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12vt: selection, close sel_buffer raceJiri Slaby1-6/+17
commit 07e6124a1a46b4b5a9b3cacc0c306b50da87abf5 upstream. syzkaller reported this UAF: BUG: KASAN: use-after-free in n_tty_receive_buf_common+0x2481/0x2940 drivers/tty/n_tty.c:1741 Read of size 1 at addr ffff8880089e40e9 by task syz-executor.1/13184 CPU: 0 PID: 13184 Comm: syz-executor.1 Not tainted 5.4.7 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: ... kasan_report+0xe/0x20 mm/kasan/common.c:634 n_tty_receive_buf_common+0x2481/0x2940 drivers/tty/n_tty.c:1741 tty_ldisc_receive_buf+0xac/0x190 drivers/tty/tty_buffer.c:461 paste_selection+0x297/0x400 drivers/tty/vt/selection.c:372 tioclinux+0x20d/0x4e0 drivers/tty/vt/vt.c:3044 vt_ioctl+0x1bcf/0x28d0 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x525/0x15a0 drivers/tty/tty_io.c:2657 vfs_ioctl fs/ioctl.c:47 [inline] It is due to a race between parallel paste_selection (TIOCL_PASTESEL) and set_selection_user (TIOCL_SETSEL) invocations. One uses sel_buffer, while the other frees it and reallocates a new one for another selection. Add a mutex to close this race. The mutex takes care properly of sel_buffer and sel_buffer_lth only. The other selection global variables (like sel_start, sel_end, and sel_cons) are protected only in set_selection_user. The other functions need quite some more work to close the races of the variables there. This is going to happen later. This likely fixes (I am unsure as there is no reproducer provided) bug 206361 too. It was marked as CVE-2020-8648. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: syzbot+59997e8d5cbdc486e6f6@syzkaller.appspotmail.com References: https://bugzilla.kernel.org/show_bug.cgi?id=206361 Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200210081131.23572-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12serial: 8250_exar: add support for ACCES cardsJay Dolan1-0/+33
commit 10c5ccc3c6d32f3d7d6c07de1d3f0f4b52f3e3ab upstream. Add ACCES VIDs and PIDs that use the Exar chips Signed-off-by: Jay Dolan <jay.dolan@accesio.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200305140504.22237-1-jay.dolan@accesio.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12tty: serial: fsl_lpuart: free IDs allocated by IDAMichael Walle1-15/+24
commit 2b2e71fe657510a6f71aa16ef0309fa6bc20ab3d upstream. Since commit 3bc3206e1c0f ("serial: fsl_lpuart: Remove the alias node dependence") the port line number can also be allocated by IDA, but in case of an error the ID will no be removed again. More importantly, any ID will be freed in remove(), even if it wasn't allocated but instead fetched by of_alias_get_id(). If it was not allocated by IDA there will be a warning: WARN(1, "ida_free called for id=%d which is not allocated.\n", id); Move the ID allocation more to the end of the probe() so that we still can use plain return in the first error cases. Fixes: 3bc3206e1c0f ("serial: fsl_lpuart: Remove the alias node dependence") Signed-off-by: Michael Walle <michael@walle.cc> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200303174306.6015-3-michael@walle.cc Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12tty:serial:mvebu-uart:fix a wrong returntangbin1-1/+1
commit 4a3e208474204e879d22a310b244cb2f39e5b1f8 upstream. in this place, the function should return a negative value and the PTR_ERR already returns a negative,so return -PTR_ERR() is wrong. Signed-off-by: tangbin <tangbin@cmss.chinamobile.com> Cc: stable <stable@vger.kernel.org> Acked-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200305013823.20976-1-tangbin@cmss.chinamobile.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12serial: ar933x_uart: set UART_CS_{RX,TX}_READY_ORIDEDaniel Golle1-0/+8
[ Upstream commit 87c5cbf71ecbb9e289d60a2df22eb686c70bf196 ] On AR934x this UART is usually not initialized by the bootloader as it is only used as a secondary serial port while the primary UART is a newly introduced NS16550-compatible. In order to make use of the ar933x-uart on AR934x without RTS/CTS hardware flow control, one needs to set the UART_CS_{RX,TX}_READY_ORIDE bits as other than on AR933x where this UART is used as primary/console, the bootloader on AR934x typically doesn't set those bits. Setting them explicitely on AR933x should not do any harm, so just set them unconditionally. Tested-by: Chuanhong Guo <gch981213@gmail.com> Signed-off-by: Daniel Golle <daniel@makrotopia.org> Link: https://lore.kernel.org/r/20200207095335.GA179836@makrotopia.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-28serdev: ttyport: restore client ops on deregistrationJohan Hovold2-6/+5
commit 0c5aae59270fb1f827acce182786094c9ccf598e upstream. The serdev tty-port controller driver should reset the tty-port client operations also on deregistration to avoid a NULL-pointer dereference in case the port is later re-registered as a normal tty device. Note that this can only happen with tty drivers such as 8250 which have statically allocated port structures that can end up being reused and where a later registration would not register a serdev controller (e.g. due to registration errors or if the devicetree has been changed in between). Specifically, this can be an issue for any statically defined ports that would be registered by 8250 core when an 8250 driver is being unbound. Fixes: bed35c6dfa6a ("serdev: add a tty port controller driver") Cc: stable <stable@vger.kernel.org> # 4.11 Reported-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20200210145730.22762-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28tty: serial: qcom_geni_serial: Fix RX cancel command failuresatya priya1-4/+14
commit 679aac5ead2f18d223554a52b543e1195e181811 upstream. RX cancel command fails when BT is switched on and off multiple times. To handle this, poll for the cancel bit in SE_GENI_S_IRQ_STATUS register instead of SE_GENI_S_CMD_CTRL_REG. As per the HPG update, handle the RX last bit after cancel command and flush out the RX FIFO buffer. Signed-off-by: satya priya <skakit@codeaurora.org> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1581415982-8793-1-git-send-email-skakit@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28tty: serial: imx: setup the correct sg entry for tx dmaFugang Duan1-1/+1
commit f76707831829530ffdd3888bebc108aecefccaa0 upstream. There has oops as below happen on i.MX8MP EVK platform that has 6G bytes DDR memory. when (xmit->tail < xmit->head) && (xmit->head == 0), it setups one sg entry with sg->length is zero: sg_set_buf(sgl + 1, xmit->buf, xmit->head); if xmit->buf is allocated from >4G address space, and SDMA only support <4G address space, then dma_map_sg() will call swiotlb_map() to do bounce buffer copying and mapping. But swiotlb_map() don't allow sg entry's length is zero, otherwise report BUG_ON(). So the patch is to correct the tx DMA scatter list. Oops: [ 287.675715] kernel BUG at kernel/dma/swiotlb.c:497! [ 287.680592] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 287.686075] Modules linked in: [ 287.689133] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.3-00016-g3fdc4e0-dirty #10 [ 287.696872] Hardware name: FSL i.MX8MP EVK (DT) [ 287.701402] pstate: 80000085 (Nzcv daIf -PAN -UAO) [ 287.706199] pc : swiotlb_tbl_map_single+0x1fc/0x310 [ 287.711076] lr : swiotlb_map+0x60/0x148 [ 287.714909] sp : ffff800010003c00 [ 287.718221] x29: ffff800010003c00 x28: 0000000000000000 [ 287.723533] x27: 0000000000000040 x26: ffff800011ae0000 [ 287.728844] x25: ffff800011ae09f8 x24: 0000000000000000 [ 287.734155] x23: 00000001b7af9000 x22: 0000000000000000 [ 287.739465] x21: ffff000176409c10 x20: 00000000001f7ffe [ 287.744776] x19: ffff000176409c10 x18: 000000000000002e [ 287.750087] x17: 0000000000000000 x16: 0000000000000000 [ 287.755397] x15: 0000000000000000 x14: 0000000000000000 [ 287.760707] x13: ffff00017f334000 x12: 0000000000000001 [ 287.766018] x11: 00000000001fffff x10: 0000000000000000 [ 287.771328] x9 : 0000000000000003 x8 : 0000000000000000 [ 287.776638] x7 : 0000000000000000 x6 : 0000000000000000 [ 287.781949] x5 : 0000000000200000 x4 : 0000000000000000 [ 287.787259] x3 : 0000000000000001 x2 : 00000001b7af9000 [ 287.792570] x1 : 00000000fbfff000 x0 : 0000000000000000 [ 287.797881] Call trace: [ 287.800328] swiotlb_tbl_map_single+0x1fc/0x310 [ 287.804859] swiotlb_map+0x60/0x148 [ 287.808347] dma_direct_map_page+0xf0/0x130 [ 287.812530] dma_direct_map_sg+0x78/0xe0 [ 287.816453] imx_uart_dma_tx+0x134/0x2f8 [ 287.820374] imx_uart_dma_tx_callback+0xd8/0x168 [ 287.824992] vchan_complete+0x194/0x200 [ 287.828828] tasklet_action_common.isra.0+0x154/0x1a0 [ 287.833879] tasklet_action+0x24/0x30 [ 287.837540] __do_softirq+0x120/0x23c [ 287.841202] irq_exit+0xb8/0xd8 [ 287.844343] __handle_domain_irq+0x64/0xb8 [ 287.848438] gic_handle_irq+0x5c/0x148 [ 287.852185] el1_irq+0xb8/0x180 [ 287.855327] cpuidle_enter_state+0x84/0x360 [ 287.859508] cpuidle_enter+0x34/0x48 [ 287.863083] call_cpuidle+0x18/0x38 [ 287.866571] do_idle+0x1e0/0x280 [ 287.869798] cpu_startup_entry+0x20/0x40 [ 287.873721] rest_init+0xd4/0xe0 [ 287.876949] arch_call_rest_init+0xc/0x14 [ 287.880958] start_kernel+0x420/0x44c [ 287.884622] Code: 9124c021 9417aff8 a94363f7 17ffffd5 (d4210000) [ 287.890718] ---[ end trace 5bc44c4ab6b009ce ]--- [ 287.895334] Kernel panic - not syncing: Fatal exception in interrupt [ 287.901686] SMP: stopping secondary CPUs [ 288.905607] SMP: failed to stop secondary CPUs 0-1 [ 288.910395] Kernel Offset: disabled [ 288.913882] CPU features: 0x0002,2000200c [ 288.917888] Memory Limit: none [ 288.920944] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]--- Reported-by: Eagle Zhou <eagle.zhou@nxp.com> Tested-by: Eagle Zhou <eagle.zhou@nxp.com> Signed-off-by: Fugang Duan <fugang.duan@nxp.com> Cc: stable <stable@vger.kernel.org> Fixes: 7942f8577f2a ("serial: imx: TX DMA: clean up sg initialization") Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/1581401761-6378-1-git-send-email-fugang.duan@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28tty/serial: atmel: manage shutdown in case of RS485 or ISO7816 modeNicolas Ferre1-1/+2
commit 04b5bfe3dc94e64d0590c54045815cb5183fb095 upstream. In atmel_shutdown() we call atmel_stop_rx() and atmel_stop_tx() functions. Prevent the rx restart that is implemented in RS485 or ISO7816 modes when calling atmel_stop_tx() by using the atomic information tasklet_shutdown that is already in place for this purpose. Fixes: 98f2082c3ac4 ("tty/serial: atmel: enforce tasklet init and termination sequences") Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200210152053.8289-1-nicolas.ferre@microchip.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28serial: 8250: Check UPF_IRQ_SHARED in advanceAndy Shevchenko4-5/+6
commit 7febbcbc48fc92e3f33863b32ed715ba4aff18c4 upstream. The commit 54e53b2e8081 ("tty: serial: 8250: pass IRQ shared flag to UART ports") nicely explained the problem: ---8<---8<--- On some systems IRQ lines between multiple UARTs might be shared. If so, the irqflags have to be configured accordingly. The reason is: The 8250 port startup code performs IRQ tests *before* the IRQ handler for that particular port is registered. This is performed in serial8250_do_startup(). This function checks whether IRQF_SHARED is configured and only then disables the IRQ line while testing. This test is performed upon each open() of the UART device. Imagine two UARTs share the same IRQ line: On is already opened and the IRQ is active. When the second UART is opened, the IRQ line has to be disabled while performing IRQ tests. Otherwise an IRQ might handler might be invoked, but the IRQ itself cannot be handled, because the corresponding handler isn't registered, yet. That's because the 8250 code uses a chain-handler and invokes the corresponding port's IRQ handling routines himself. Unfortunately this IRQF_SHARED flag isn't configured for UARTs probed via device tree even if the IRQs are shared. This way, the actual and shared IRQ line isn't disabled while performing tests and the kernel correctly detects a spurious IRQ. So, adding this flag to the DT probe solves the issue. Note: The UPF_SHARE_IRQ flag is configured unconditionally. Therefore, the IRQF_SHARED flag can be set unconditionally as well. Example stack trace by performing `echo 1 > /dev/ttyS2` on a non-patched system: |irq 85: nobody cared (try booting with the "irqpoll" option) | [...] |handlers: |[<ffff0000080fc628>] irq_default_primary_handler threaded [<ffff00000855fbb8>] serial8250_interrupt |Disabling IRQ #85 ---8<---8<--- But unfortunately didn't fix the root cause. Let's try again here by moving IRQ flag assignment from serial_link_irq_chain() to serial8250_do_startup(). This should fix the similar issue reported for 8250_pnp case. Since this change we don't need to have custom solutions in 8250_aspeed_vuart and 8250_of drivers, thus, drop them. Fixes: 1c2f04937b3e ("serial: 8250: add IRQ trigger support") Reported-by: Li RongQing <lirongqing@baidu.com> Cc: Kurt Kanzenbach <kurt@linutronix.de> Cc: Vikram Pandita <vikram.pandita@ti.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: stable <stable@vger.kernel.org> Acked-by: Kurt Kanzenbach <kurt@linutronix.de> Link: https://lore.kernel.org/r/20200211135559.85960-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>