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path: root/drivers/tty/tty_io.c
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2023-04-27Merge tag 'driver-core-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.4-rc1. Once again, a busy development cycle, with lots of changes happening in the driver core in the quest to be able to move "struct bus" and "struct class" into read-only memory, a task now complete with these changes. This will make the future rust interactions with the driver core more "provably correct" as well as providing more obvious lifetime rules for all busses and classes in the kernel. The changes required for this did touch many individual classes and busses as many callbacks were changed to take const * parameters instead. All of these changes have been submitted to the various subsystem maintainers, giving them plenty of time to review, and most of them actually did so. Other than those changes, included in here are a small set of other things: - kobject logging improvements - cacheinfo improvements and updates - obligatory fw_devlink updates and fixes - documentation updates - device property cleanups and const * changes - firwmare loader dependency fixes. All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits) device property: make device_property functions take const device * driver core: update comments in device_rename() driver core: Don't require dynamic_debug for initcall_debug probe timing firmware_loader: rework crypto dependencies firmware_loader: Strip off \n from customized path zram: fix up permission for the hot_add sysfs file cacheinfo: Add use_arch[|_cache]_info field/function arch_topology: Remove early cacheinfo error message if -ENOENT cacheinfo: Check cache properties are present in DT cacheinfo: Check sib_leaf in cache_leaves_are_shared() cacheinfo: Allow early level detection when DT/ACPI info is missing/broken cacheinfo: Add arm64 early level initializer implementation cacheinfo: Add arch specific early level initializer tty: make tty_class a static const structure driver core: class: remove struct class_interface * from callbacks driver core: class: mark the struct class in struct class_interface constant driver core: class: make class_register() take a const * driver core: class: mark class_release() as taking a const * driver core: remove incorrect comment for device_create* MIPS: vpe-cmp: remove module owner pointer from struct class usage. ...
2023-04-03tty: make tty_class a static const structureGreg Kroah-Hartman
Now that the driver core allows for struct class to be in read-only memory, move the tty_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Cc: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/2023040250-landowner-unfitted-11f4@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29tty: Prevent writing chars during tcsetattr TCSADRAIN/FLUSHIlpo Järvinen
If userspace races tcsetattr() with a write, the drained condition might not be guaranteed by the kernel. There is a race window after checking Tx is empty before tty_set_termios() takes termios_rwsem for write. During that race window, more characters can be queued by a racing writer. Any ongoing transmission might produce garbage during HW's ->set_termios() call. The intent of TCSADRAIN/FLUSH seems to be preventing such a character corruption. If those flags are set, take tty's write lock to stop any writer before performing the lower layer Tx empty check and wait for the pending characters to be sent (if any). The initial wait for all-writers-done must be placed outside of tty's write lock to avoid deadlock which makes it impossible to use tty_wait_until_sent(). The write lock is retried if a racing write is detected. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230317113318.31327-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17driver core: class: remove module * from class_create()Greg Kroah-Hartman
The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09tty: simplify sysctl registrationLuis Chamberlain
register_sysctl_table() is a deprecated compatibility wrapper. register_sysctl_init() can do the directory creation for you so just use that Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20230302204612.782387-7-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: fix out-of-bounds access in tty_driver_lookup_tty()Sven Schnelle
When specifying an invalid console= device like console=tty3270, tty_driver_lookup_tty() returns the tty struct without checking whether index is a valid number. To reproduce: qemu-system-x86_64 -enable-kvm -nographic -serial mon:stdio \ -kernel ../linux-build-x86/arch/x86/boot/bzImage \ -append "console=ttyS0 console=tty3270" This crashes with: [ 0.770599] BUG: kernel NULL pointer dereference, address: 00000000000000ef [ 0.771265] #PF: supervisor read access in kernel mode [ 0.771773] #PF: error_code(0x0000) - not-present page [ 0.772609] Oops: 0000 [#1] PREEMPT SMP PTI [ 0.774878] RIP: 0010:tty_open+0x268/0x6f0 [ 0.784013] chrdev_open+0xbd/0x230 [ 0.784444] ? cdev_device_add+0x80/0x80 [ 0.784920] do_dentry_open+0x1e0/0x410 [ 0.785389] path_openat+0xca9/0x1050 [ 0.785813] do_filp_open+0xaa/0x150 [ 0.786240] file_open_name+0x133/0x1b0 [ 0.786746] filp_open+0x27/0x50 [ 0.787244] console_on_rootfs+0x14/0x4d [ 0.787800] kernel_init_freeable+0x1e4/0x20d [ 0.788383] ? rest_init+0xc0/0xc0 [ 0.788881] kernel_init+0x11/0x120 [ 0.789356] ret_from_fork+0x22/0x30 Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221209112737.3222509-2-svens@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-16Merge tag 'driver-core-6.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems" * tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits) device property: Fix documentation for fwnode_get_next_parent() firmware_loader: fix up to_fw_sysfs() to preserve const usb.h: take advantage of container_of_const() device.h: move kobj_to_dev() to use container_of_const() container_of: add container_of_const() that preserves const-ness of the pointer driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion. driver core: fix up missed scsi/cxlflash class.devnode() conversion. driver core: fix up some missing class.devnode() conversions. driver core: make struct class.devnode() take a const * driver core: make struct class.dev_uevent() take a const * cacheinfo: Remove of_node_put() for fw_token device property: Add a blank line in Kconfig of tests device property: Rename goto label to be more precise device property: Move PROPERTY_ENTRY_BOOL() a bit down device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*() kernfs: fix all kernel-doc warnings and multiple typos driver core: pass a const * into of_device_uevent() kobject: kset_uevent_ops: make name() callback take a const * kobject: kset_uevent_ops: make filter() callback take a const * kobject: make kobject_namespace take a const * ...
2022-12-16Merge tag 'tty-6.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Here is the "big" set of tty/serial driver changes for 6.2-rc1. As in previous kernel releases, nothing big here at all, just some small incremental serial/tty layer cleanups and some individual driver additions and fixes. Highlights are: - serial helper macros from Jiri Slaby to reduce the amount of duplicated code in serial drivers - api cleanups and consolidations from Ilpo Järvinen in lots of serial drivers - the usual set of n_gsm fixes from Daniel Starke as that code gets exercised more - TIOCSTI is finally able to be disabled if requested (security hardening feature from Kees Cook) - fsl_lpuart driver fixes and features added - other small serial driver additions and fixes All of these have been in linux-next for a while with no reported problems" * tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (97 commits) serial: atmel: don't stop the transmitter when doing PIO serial: atmel: cleanup atmel_start+stop_tx() tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* API serial: sunsab: Fix error handling in sunsab_init() serial: altera_uart: fix locking in polling mode serial: pch: Fix PCI device refcount leak in pch_request_dma() tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unused tty: serial: fsl_lpuart: Add runtime pm support tty: serial: fsl_lpuart: enable wakeup source for lpuart serdev: Replace poll loop by readx_poll_timeout() macro tty: synclink_gt: unwind actions in error path of net device open serial: stm32: move dma_request_chan() before clk_prepare_enable() dt-bindings: serial: xlnx,opb-uartlite: Drop 'contains' from 'xlnx,use-parity' serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle. serial: amba-pl011: avoid SBSA UART accessing DMACR register tty: serial: altera_jtaguart: remove struct altera_jtaguart tty: serial: altera_jtaguart: use uart_port::read_status_mask tty: serial: altera_jtaguart: remove unused altera_jtaguart::sigs tty: serial: altera_jtaguart: remove flag from altera_jtaguart_rx_chars() n_tty: Rename tail to old_tail in n_tty_read() ...
2022-12-02tty: tty_io: use console_list_lock for list synchronizationJohn Ogness
show_cons_active() uses the console_lock to gather information on registered consoles. It requires that no consoles are unregistered until it is finished. The console_list_lock should be used because list synchronization responsibility will be removed from the console_lock in a later change. Note, the console_lock is still needed to serialize the device() callback with other console operations. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-34-john.ogness@linutronix.de
2022-12-02tty: tty_io: document console_lock usageJohn Ogness
show_cons_active() uses the console_lock to gather information on registered consoles. Since the console_lock is being used for multiple reasons, explicitly document these reasons. This will be useful when the console_lock is split into fine-grained locking. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-10-john.ogness@linutronix.de
2022-11-24driver core: make struct class.devnode() take a const *Greg Kroah-Hartman
The devnode() in struct class should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <axboe@kernel.dk> Cc: Justin Sanders <justin@coraid.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Benjamin Gaignard <benjamin.gaignard@collabora.com> Cc: Liam Mark <lmark@codeaurora.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Brian Starkey <Brian.Starkey@arm.com> Cc: John Stultz <jstultz@google.com> Cc: "Christian König" <christian.koenig@amd.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Sean Young <sean@mess.org> Cc: Frank Haverkamp <haver@linux.ibm.com> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Xie Yongji <xieyongji@bytedance.com> Cc: Gautam Dawar <gautam.dawar@xilinx.com> Cc: Dan Carpenter <error27@gmail.com> Cc: Eli Cohen <elic@nvidia.com> Cc: Parav Pandit <parav@nvidia.com> Cc: Maxime Coquelin <maxime.coquelin@redhat.com> Cc: alsa-devel@alsa-project.org Cc: dri-devel@lists.freedesktop.org Cc: kvm@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: linux-block@vger.kernel.org Cc: linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-08tty: Move TIOCSTI toggle variable before kerndocKees Cook
The variable "tty_legacy_tiocsti" should be defined before the kerndoc for the tiocsti() function. The new variable was breaking the "htmldocs" build target: drivers/tty/tty_io.c:2271: warning: cannot understand function prototype: 'bool tty_legacy_tiocsti __read_mostly = IS_ENABLED(CONFIG_LEGACY_TIOCSTI); ' Fixes: 83efeeeb3d04 ("tty: Allow TIOCSTI to be disabled") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/lkml/20221107143434.66f7be35@canb.auug.org.au Cc: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20221107034631.never.637-kees@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03tty: Allow TIOCSTI to be disabledKees Cook
TIOCSTI continues its long history of being used in privilege escalation attacks[1]. Prior attempts to provide a mechanism to disable this have devolved into discussions around creating full-blown LSMs to provide arbitrary ioctl filtering, which is hugely over-engineered -- only TIOCSTI is being used this way. 3 years ago OpenBSD entirely removed TIOCSTI[2], Android has had it filtered for longer[3], and the tools that had historically used TIOCSTI either do not need it, are not commonly built with it, or have had its use removed. Provide a simple CONFIG and global sysctl to disable this for the system builders who have wanted this functionality for literally decades now, much like the ldisc_autoload CONFIG and sysctl. [1] https://lore.kernel.org/linux-hardening/Y0m9l52AKmw6Yxi1@hostpad [2] https://undeadly.org/cgi?action=article;sid=20170701132619 [3] https://lore.kernel.org/lkml/CAFJ0LnFGRuEEn1tCLhoki8ZyWrKfktbF+rwwN7WzyC_kBFoQVA@mail.gmail.com/ Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Simon Brand <simon.brand@postadigitale.de> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221022182949.2684794-2-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03tty: Move sysctl setup into "core" tty logicKees Cook
In preparation for adding another sysctl to the tty subsystem, move the tty setup code into the "core" tty code, which contains tty_init() itself. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221022182949.2684794-1-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-22tty: remove TTY_DRIVER_MAGICнаб
According to Greg, in the context of magic numbers as defined in magic-number.rst, "the tty layer should not need this and I'll gladly take patches" Acked-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Ref: https://lore.kernel.org/linux-doc/YyMlovoskUcHLEb7@kroah.com/ Link: https://lore.kernel.org/r/723478a270a3858f27843cbec621df4d5d44efcc.1663288066.git.nabijaczleweli@nabijaczleweli.xyz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-22tty: remove TTY_MAGICнаб
According to Greg, in the context of magic numbers as defined in magic-number.rst, "the tty layer should not need this and I'll gladly take patches" Acked-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Ref: https://lore.kernel.org/linux-doc/YyMlovoskUcHLEb7@kroah.com/ Link: https://lore.kernel.org/r/476d024cd6b04160a5de381ea2b9856b60088cbd.1663288066.git.nabijaczleweli@nabijaczleweli.xyz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-09termios: start unifying non-UAPI parts of asm/termios.hAl Viro
* new header (linut/termios_internal.h), pulled by the users of those suckers * defaults for INIT_C_CC and externs for conversion helpers moved over there * remove termios-base.h (empty now) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/YxDmptU7dNGZ+/Hn@ZenIV Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-10tty: fix typos in commentsJulia Lawall
Spelling mistakes (triple letters) in comments. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Link: https://lore.kernel.org/r/20220521111145.81697-95-Julia.Lawall@inria.fr Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-22memcg: enable accounting for tty-related objectsVasily Averin
At each login the user forces the kernel to create a new terminal and allocate up to ~1Kb memory for the tty-related structures. By default it's allowed to create up to 4096 ptys with 1024 reserve for initial mount namespace only and the settings are controlled by host admin. Though this default is not enough for hosters with thousands of containers per node. Host admin can be forced to increase it up to NR_UNIX98_PTY_MAX = 1<<20. By default container is restricted by pty mount_opt.max = 1024, but admin inside container can change it via remount. As a result, one container can consume almost all allowed ptys and allocate up to 1Gb of unaccounted memory. It is not enough per-se to trigger OOM on host, however anyway, it allows to significantly exceed the assigned memcg limit and leads to troubles on the over-committed node. It makes sense to account for them to restrict the host's memory consumption from inside the memcg-limited container. Link: https://lkml.kernel.org/r/5d4bca06-7d4f-a905-e518-12981ebca1b3@virtuozzo.com Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-21tty: tty_io: Switch to vmalloc() fallback in case of TTY_NO_WRITE_SPLITAndy Shevchenko
When TTY_NO_WRITE_SPLIT is set and 64 KiB chunks are used, allow vmalloc() fallback. Supply __GFP_RETRY_MAYFAIL to make kmalloc() preferable over vmalloc() since we may want a better performance. Note, both current users copy data to another buffer anyway, so the type of our allocation doesn't affect their expectations. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211220133250.3070-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26tty: add kernel-doc for tty_standard_installJiri Slaby
It is the only missing exported function which is not documented. Fix it. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211126081611.11001-23-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26tty: add kernel-doc for more tty_driver functionsJiri Slaby
The only documented function for tty_driver structure allocation/registration was __tty_alloc_driver(). Fix highlighting in that comment. And add kernel-doc headers to all tty_driver_kref_put(), tty_register_driver(), and tty_unregister_driver() -- i.e. the main ones. More to follow later. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211126081611.11001-18-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26tty: reformat kernel-doc in tty_io.cJiri Slaby
Kernel-doc is a bit strict about some formatting. So fix these: 1) When there is a tab in comments, it thinks the line is a continuation one. So the description of the functions end up as descriptions of the last parameter described. Remove the tabs. 2) Remove newlines before parameters description and after the comments. This was not wrong per se, only inconsistent with the rest of the file. 3) Add periods to the end of sentences where appropriate. 4) Add "()" to function names and "%" to constants, so that they are properly highlighted. By the above, this patch also unifies these docs with the other kernel-doc's in this file. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211126081611.11001-13-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: remove file from tty_ldisc_ops::ioctl and compat_ioctlJiri Slaby
After the previous patches, noone needs 'file' parameter in neither ioctl hook from tty_ldisc_ops. So remove 'file' from both of them. Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Cc: Wolfgang Grandegger <wg@grandegger.com> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Andreas Koensgen <ajk@comnets.uni-bremen.de> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> [NFC] Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211122094529.24171-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: clean up whitespace in __do_SAK()Jiri Slaby
Remove spaces before the 'i' variable declaration and wrap parameters of group_send_sig_info(). Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: remove tty NULL check from __do_SAK()Jiri Slaby
Both do_SAK_work() and vc_SAK() provide a valid tty to __do_SAK(), so remove the check. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: remove TTY_SOFT_SAK part from __do_SAK()Jiri Slaby
Remove the TTY_SOFT_SAK part. It is never defined, so this is only confusing. It was actually never defined since its introduction in 0.99.14g. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-26tty: Fix data race between tiocsti() and flush_to_ldisc()Nguyen Dinh Phi
The ops->receive_buf() may be accessed concurrently from these two functions. If the driver flushes data to the line discipline receive_buf() method while tiocsti() is waiting for the ops->receive_buf() to finish its work, the data race will happen. For example: tty_ioctl |tty_ldisc_receive_buf ->tioctsi | ->tty_port_default_receive_buf | ->tty_ldisc_receive_buf ->hci_uart_tty_receive | ->hci_uart_tty_receive ->h4_recv | ->h4_recv In this case, the h4 receive buffer will be overwritten by the latecomer, and we will lost the data. Hence, change tioctsi() function to use the exclusive lock interface from tty_buffer to avoid the data race. Reported-by: syzbot+97388eb9d31b997fe1d0@syzkaller.appspotmail.com Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com> Link: https://lore.kernel.org/r/20210823000641.2082292-1-phind.uet@gmail.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27tty: drop put_tty_driverJiri Slaby
put_tty_driver() is an alias for tty_driver_kref_put(). There is no need for two exported identical functions, therefore switch all users of old put_tty_driver() to new tty_driver_kref_put() and remove the former for good. Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com> Cc: Jens Taprogge <jens.taprogge@taprogge.org> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Scott Branden <scott.branden@broadcom.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Lin <dtwlin@gmail.com> Cc: Johan Hovold <johan@kernel.org> Cc: Alex Elder <elder@kernel.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Oliver Neukum <oneukum@suse.com> Cc: Felipe Balbi <balbi@kernel.org> Cc: Mathias Nyman <mathias.nyman@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Acked-by: Alex Elder <elder@linaro.org> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: David Sterba <dsterba@suse.com> Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210723074317.32690-8-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27tty: make tty_set_operations an inlineJiri Slaby
Since commit f34d7a5b7010 (tty: The big operations rework) in 2008, tty_set_operations() is a simple one-line assignment. There is no reason for this to be an exported function, hence move it to a header and make an inline from that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210723074317.32690-7-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-20tty: fix kernel-doc for {start,stop}_ttyJiri Slaby
Commit f9e053dcfc02 (tty: Serialize tty flow control changes with flow_lock) renamed start_tty to __start_tty and stop_tty to __stop_tty and introduced new start_tty and stop_tty. But it left kernel-doc comments on the old locations: tty_io.c:785: warning: expecting prototype for stop_tty(). Prototype was for __stop_tty() instead tty_io.c:816: warning: expecting prototype for start_tty(). Prototype was for __start_tty() instead Fix that by moving the comments to appropriate locations. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210519072153.3859-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-20tty: fix kernel-doc for tty_{read,write}Jiri Slaby
After commits a9cbbb80e3e7 (tty: avoid using vfs_iocb_iter_write() for redirected console writes) and dd78b0c483e3 (tty: implement read_iter), the tty_read and tty_write kernel-doc comments don't match the code: tty_io.c:931: warning: Function parameter or member 'iocb' not described in 'tty_read' tty_io.c:931: warning: Function parameter or member 'to' not described in 'tty_read' tty_io.c:931: warning: Excess function parameter 'file' description in 'tty_read' tty_io.c:931: warning: Excess function parameter 'buf' description in 'tty_read' tty_io.c:931: warning: Excess function parameter 'count' description in 'tty_read' tty_io.c:931: warning: Excess function parameter 'ppos' description in 'tty_read' tty_io.c:1115: warning: Function parameter or member 'iocb' not described in 'file_tty_write' tty_io.c:1115: warning: Function parameter or member 'from' not described in 'file_tty_write' tty_io.c:1115: warning: expecting prototype for tty_write(). Prototype was for file_tty_write() instead Fix them to correspond the reality, i.e. the switch from read/write to read_iter/write_iter. Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210519072153.3859-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Remove return in void functionXiaofei Tan
Remove return in void function, reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-15-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Delete a blank line before EXPORT_SYMBOL(foo)Xiaofei Tan
Delete a blank line before EXPORT_SYMBOL(foo) so that EXPORT_SYMBOL(foo) immediately follow its function/variable, reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-14-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Fix an issue of code indent for conditional statementsXiaofei Tan
Fix an issue of code indent for conditional statements,reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-13-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Remove the repeated word 'can'Xiaofei Tan
Remove the repeated word 'can' following advice of checkpatch.pl Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-12-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Fix coding style issues of block commentsXiaofei Tan
Fix coding style issues of block comments, reported by checkpatch.pl. Besides, add a period at the end of the sentenses. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-11-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Fix trailing whitespace issuesXiaofei Tan
Fix trailing whitespace issues, reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-10-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Fix spaces required around that ':'Xiaofei Tan
Fix spaces required around that ':', reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-9-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Add a blank line after declarationsXiaofei Tan
Add a blank line after declarations, reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-8-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: tty_io: Remove spaces before tabsXiaofei Tan
Remove spaces before tabs following the advice of checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1620811585-18582-7-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: cumulate and document tty_struct::ctrl* membersJiri Slaby
Group the ctrl members under a single struct called ctrl. The new struct contains 'pgrp', 'session', 'pktstatus', and 'packet'. 'pktstatus' and 'packet' used to be bits in a bitfield. The struct also contains the lock protecting them to share the same cache line. Note that commit c545b66c6922b (tty: Serialize tcflow() with other tty flow control changes) added a padding to the original bitfield. It was for the bitfield to occupy a whole 64b word to avoid interferring stores on Alpha (cannot we evaporate this arch with weird implications to C code yet?). But it doesn't work as expected as the padding (tty_struct::ctrl_unused) is aligned to a 8B boundary too and occupies some bytes from the next word. So make it reliable by: 1) setting __aligned of the struct -- that aligns the start, and 2) making 'unsigned long unused[0]' as the last member of the struct -- pads the end. Add a kerneldoc comment for this grouped members. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/20210505091928.22010-14-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: cumulate and document tty_struct::flow* membersJiri Slaby
Group the flow flags under a single struct called flow. The new struct contains 'stopped' and 'tco_stopped' bools which used to be bits in a bitfield. The struct also contains the lock protecting them to potentially share the same cache line. Note that commit c545b66c6922b (tty: Serialize tcflow() with other tty flow control changes) added a padding to the original bitfield. It was for the bitfield to occupy a whole 64b word to avoid interferring stores on Alpha (cannot we evaporate this arch with weird implications to C code yet?). But it doesn't work as expected as the padding (tty_struct::unused) is aligned to a 8B boundary too and occupies some bytes from the next word. So make it reliable by: 1) setting __aligned of the struct -- that aligns the start, and 2) making 'unsigned long unused[0]' as the last member of the struct -- pads the end. This is also the perfect time to start the documentation of tty_struct where all this lives. So we start by documenting what these bools actually serve for. And why we do all the alignment dances. Only the few up-to-date information from the Theodore's comment made it into this new Kerneldoc comment. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk> Link: https://lore.kernel.org/r/20210505091928.22010-13-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-15tty: make tty_release_redirect() staticGreg Kroah-Hartman
No one calls this outside of the tty_io.c file, so mark this static and do not export the symbol anymore. Cc: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20210408125134.3016837-11-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-15tty: create internal tty.h fileGreg Kroah-Hartman
There are a number of functions and #defines in include/linux/tty.h that do not belong there as they are private to the tty core code. Create an initial drivers/tty/tty.h file and copy the odd "tty logging" macros into it to seed the file with some initial things that we know nothing outside of the tty core should be calling. Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20210408125134.3016837-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10tty: refactor TIOCSSERIAL handlingJohan Hovold
Factor out the deprecated serial flags handling and tty-operation check shared with the compat TIOCSSERIAL handler. Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407095208.31838-6-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10tty: use pr_warn_ratelimited() for deprecated serial flagsJohan Hovold
Use pr_warn_ratelimited() when warning about deprecated serial flags instead of open coding. Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407095208.31838-5-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10tty: fix return value for unsupported ioctlsJohan Hovold
Drivers should return -ENOTTY ("Inappropriate I/O control operation") when an ioctl isn't supported, while -EINVAL is used for invalid arguments. Fix up the TIOCMGET, TIOCMSET and TIOCGICOUNT helpers which returned -EINVAL when a tty driver did not implement the corresponding operations. Note that the TIOCMGET and TIOCMSET helpers predate git and do not get a corresponding Fixes tag below. Fixes: d281da7ff6f7 ("tty: Make tiocgicount a handler") Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407095208.31838-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-15Merge 5.12-rc3 into tty-nextGreg Kroah-Hartman
Resolves a merge issue with: drivers/tty/hvc/hvcs.c and we want the tty/serial fixes from 5.12-rc3 in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10tty: localise ptychar and make it constJiri Slaby
ptychar was not const, so mark it as such. And move this variable to the only place where it's used. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210302062214.29627-36-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>