kernel/linux.git/drivers/tty/serial, branch v4.4.171

drivers/tty: add missing of_node_put()

2018-12-21T13:09:52+00:00

[ Upstream commit dac097c4546e4c5b16dd303a1e97c1d319c8ab3e ] of_find_node_by_path() acquires a reference to the node returned by it and that reference needs to be dropped by its caller. This place is not doing this, so fix it. Signed-off-by: Yangtao Li Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

kgdboc: fix KASAN global-out-of-bounds bug in param_set_kgdboc_var()

2018-12-13T08:21:37+00:00

commit dada6a43b0402eba438a17ac86fdc64ac56a4607 upstream. This patch is trying to fix KE issue due to "BUG: KASAN: global-out-of-bounds in param_set_kgdboc_var+0x194/0x198" reported by Syzkaller scan." [26364:syz-executor0][name:report8t]BUG: KASAN: global-out-of-bounds in param_set_kgdboc_var+0x194/0x198 [26364:syz-executor0][name:report&]Read of size 1 at addr ffffff900e44f95f by task syz-executor0/26364 [26364:syz-executor0][name:report&] [26364:syz-executor0]CPU: 7 PID: 26364 Comm: syz-executor0 Tainted: G W 0 [26364:syz-executor0]Call trace: [26364:syz-executor0][] dump_bacIctrace+Ox0/0x470 [26364:syz-executor0][] show_stack+0x20/0x30 [26364:syz-executor0][] dump_stack+Oxd8/0x128 [26364:syz-executor0][] print_address_description +0x80/0x4a8 [26364:syz-executor0][] kasan_report+Ox178/0x390 [26364:syz-executor0][] _asan_report_loadi_noabort+Ox18/0x20 [26364:syz-executor0][] param_set_kgdboc_var+Ox194/0x198 [26364:syz-executor0][] param_attr_store+Ox14c/0x270 [26364:syz-executor0][] module_attr_store+0x60/0x90 [26364:syz-executor0][] sysfs_kl_write+Ox100/0x158 [26364:syz-executor0][] kernfs_fop_write+0x27c/0x3a8 [26364:syz-executor0][] do_loop_readv_writev+0x114/0x1b0 [26364:syz-executor0][] do_readv_writev+0x4f8/0x5e0 [26364:syz-executor0][] vfs_writev+0x7c/Oxb8 [26364:syz-executor0][] SyS_writev+Oxcc/0x208 [26364:syz-executor0][] elO_svc_naked +0x24/0x28 [26364:syz-executor0][name:report&] [26364:syz-executor0][name:report&]The buggy address belongs to the variable: [26364:syz-executor0][name:report&] kgdb_tty_line+Ox3f/0x40 [26364:syz-executor0][name:report&] [26364:syz-executor0][name:report&]Memory state around the buggy address: [26364:syz-executor0] ffffff900e44f800: 00 00 00 00 00 04 fa fa fa fa fa fa 00 fa fa fa [26364:syz-executor0] ffffff900e44f880: fa fa fa fa 00 fa fa fa fa fa fa fa 00 fa fa fa [26364:syz-executor0]> ffffff900e44f900: fa fa fa fa 04 fa fa fa fa fa fa fa 00 00 00 00 [26364:syz-executor0][name:report&] ^ [26364:syz-executor0] ffffff900e44f980: 00 fa fa fa fa fa fa fa 04 fa fa fa fa fa fa fa [26364:syz-executor0] ffffff900e44fa00: 04 fa fa fa fa fa fa fa 00 fa fa fa fa fa fa fa [26364:syz-executor0][name:report&] [26364:syz-executor0][name:panic&]Disabling lock debugging due to kernel taint [26364:syz-executor0]------------[cut here]------------ After checking the source code, we've found there might be an out-of-bounds access to "config[len - 1]" array when the variable "len" is zero. Signed-off-by: Macpaul Lin Acked-by: Daniel Thompson Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

tty: serial: 8250_mtk: always resume the device in probe.

2018-12-13T08:21:37+00:00

commit 100bc3e2bebf95506da57cbdf5f26b25f6da4c81 upstream. serial8250_register_8250_port calls uart_config_port, which calls config_port on the port before it tries to power on the port. So we need the port to be on before calling serial8250_register_8250_port. Change the code to always do a runtime resume in probe before registering port, and always do a runtime suspend in remove. This basically reverts the change in commit 68e5fc4a255a ("tty: serial: 8250_mtk: use pm_runtime callbacks for enabling"), but still use pm_runtime callbacks. Fixes: 68e5fc4a255a ("tty: serial: 8250_mtk: use pm_runtime callbacks for enabling") Signed-off-by: Peter Shih Cc: stable Signed-off-by: Greg Kroah-Hartman

kgdboc: Fix warning with module build

2018-12-13T08:21:30+00:00

commit 1cd25cbb2fedbc777f3a8c3cb1ba69b645aeaa64 upstream. After 2dd453168643 ("kgdboc: Fix restrict error"), kgdboc_option_setup is now only used when built in, resulting in a warning when compiled as a module: drivers/tty/serial/kgdboc.c:134:12: warning: 'kgdboc_option_setup' defined but not used [-Wunused-function] static int kgdboc_option_setup(char *opt) ^~~~~~~~~~~~~~~~~~~ Move the function under the appropriate ifdef for builtin only. Fixes: 2dd453168643 ("kgdboc: Fix restrict error") Reported-by: Stephen Rothwell Signed-off-by: Laura Abbott Signed-off-by: Greg Kroah-Hartman

kgdboc: Fix restrict error

2018-12-13T08:21:30+00:00

commit 2dd453168643d9475028cd867c57e65956a0f7f9 upstream. There's an error when compiled with restrict: drivers/tty/serial/kgdboc.c: In function ‘configure_kgdboc’: drivers/tty/serial/kgdboc.c:137:2: error: ‘strcpy’ source argument is the same as destination [-Werror=restrict] strcpy(config, opt); ^~~~~~~~~~~~~~~~~~~ As the error implies, this is from trying to use config as both source and destination. Drop the call to the function where config is the argument since nothing else happens in the function. Signed-off-by: Laura Abbott Reviewed-by: Daniel Thompson Signed-off-by: Greg Kroah-Hartman

sc16is7xx: Fix for multi-channel stall

2018-11-21T08:27:39+00:00

[ Upstream commit 8344498721059754e09d30fe255a12dab8fb03ef ] The SC16IS752 is a dual-channel device. The two channels are largely independent, but the IRQ signals are wired together as an open-drain, active low signal which will be driven low while either of the channels requires attention, which can be for significant periods of time until operations complete and the interrupt can be acknowledged. In that respect it is should be treated as a true level-sensitive IRQ. The kernel, however, needs to be able to exit interrupt context in order to use I2C or SPI to access the device registers (which may involve sleeping). Therefore the interrupt needs to be masked out or paused in some way. The usual way to manage sleeping from within an interrupt handler is to use a threaded interrupt handler - a regular interrupt routine does the minimum amount of work needed to triage the interrupt before waking the interrupt service thread. If the threaded IRQ is marked as IRQF_ONESHOT the kernel will automatically mask out the interrupt until the thread runs to completion. The sc16is7xx driver used to use a threaded IRQ, but a patch switched to using a kthread_worker in order to set realtime priorities on the handler thread and for other optimisations. The end result is non-threaded IRQ that schedules some work then returns IRQ_HANDLED, making the kernel think that all IRQ processing has completed. The work-around to prevent a constant stream of interrupts is to mark the interrupt as edge-sensitive rather than level-sensitive, but interpreting an active-low source as a falling-edge source requires care to prevent a total cessation of interrupts. Whereas an edge-triggering source will generate a new edge for every interrupt condition a level-triggering source will keep the signal at the interrupting level until it no longer requires attention; in other words, the host won't see another edge until all interrupt conditions are cleared. It is therefore vital that the interrupt handler does not exit with an outstanding interrupt condition, otherwise the kernel will not receive another interrupt unless some other operation causes the interrupt state on the device to be cleared. The existing sc16is7xx driver has a very simple interrupt "thread" (kthread_work job) that processes interrupts on each channel in turn until there are no more. If both channels are active and the first channel starts interrupting while the handler for the second channel is running then it will not be detected and an IRQ stall ensues. This could be handled easily if there was a shared IRQ status register, or a convenient way to determine if the IRQ had been deasserted for any length of time, but both appear to be lacking. Avoid this problem (or at least make it much less likely to happen) by reducing the granularity of per-channel interrupt processing to one condition per iteration, only exiting the overall loop when both channels are no longer interrupting. Signed-off-by: Phil Elwell Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

kgdboc: Passing ekgdboc to command line causes panic

2018-11-21T08:27:36+00:00

commit 1bd54d851f50dea6af30c3e6ff4f3e9aab5558f9 upstream. kgdboc_option_setup does not check input argument before passing it to strlen. The argument would be a NULL pointer if "ekgdboc", without its value, is set in command line and thus cause the following panic. PANIC: early exception 0xe3 IP 10:ffffffff8fbbb620 error 0 cr2 0x0 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #1 [ 0.000000] RIP: 0010:strlen+0x0/0x20 ... [ 0.000000] Call Trace [ 0.000000] ? kgdboc_option_setup+0x9/0xa0 [ 0.000000] ? kgdboc_early_init+0x6/0x1b [ 0.000000] ? do_early_param+0x4d/0x82 [ 0.000000] ? parse_args+0x212/0x330 [ 0.000000] ? rdinit_setup+0x26/0x26 [ 0.000000] ? parse_early_options+0x20/0x23 [ 0.000000] ? rdinit_setup+0x26/0x26 [ 0.000000] ? parse_early_param+0x2d/0x39 [ 0.000000] ? setup_arch+0x2f7/0xbf4 [ 0.000000] ? start_kernel+0x5e/0x4c2 [ 0.000000] ? load_ucode_bsp+0x113/0x12f [ 0.000000] ? secondary_startup_64+0xa5/0xb0 This patch adds a check to prevent the panic. Cc: stable@vger.kernel.org Cc: jason.wessel@windriver.com Cc: gregkh@linuxfoundation.org Cc: jslaby@suse.com Signed-off-by: He Zhe Reviewed-by: Daniel Thompson Signed-off-by: Greg Kroah-Hartman

tty: serial: sprd: fix error return code in sprd_probe()

2018-11-10T15:41:39+00:00

[ Upstream commit ec085c5a51b768947ca481f90b66653e36b3c566 ] platform_get_irq() returns an error code, but the sprd_serial driver ignores it and always returns -ENODEV. This is not correct and, prevents -EPROBE_DEFER from being propagated properly. Also, notice that platform_get_irq() no longer returns 0 on error: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af Print and propagate the return value of platform_get_irq on failure. This issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: imx: restore handshaking irq for imx1

2018-10-10T06:52:08+00:00

commit 7e620984b62532783912312e334f3c48cdacbd5d upstream. Back in 2015 when irda was dropped from the driver imx1 was broken. This change reintroduces the support for the third interrupt of the UART. Fixes: afe9cbb1a6ad ("serial: imx: drop support for IRDA") Cc: stable Signed-off-by: Uwe Kleine-König Reviewed-by: Leonard Crestez Signed-off-by: Greg Kroah-Hartman

serial: cpm_uart: return immediately from console poll

2018-10-10T06:52:07+00:00

commit be28c1e3ca29887e207f0cbcd294cefe5074bab6 upstream. kgdb expects poll function to return immediately and returning NO_POLL_CHAR when no character is available. Fixes: f5316b4aea024 ("kgdb,8250,pl011: Return immediately from console poll") Cc: Jason Wessel Cc: Signed-off-by: Christophe Leroy Signed-off-by: Greg Kroah-Hartman