kernel/linux.git/drivers/tty/tty_io.c, branch v6.6.132

tty: ldsic: fix tty_ldisc_autoload sysctl's proc_handler

2024-12-09T09:32:45+00:00

commit 635a9fca54f4f4148be1ae1c7c6bd37af80f5773 upstream. Commit 7c0cca7c847e ("tty: ldisc: add sysctl to prevent autoloading of ldiscs") introduces the tty_ldisc_autoload sysctl with the wrong proc_handler. .extra1 and .extra2 parameters are set to avoid other values thant SYSCTL_ZERO or SYSCTL_ONE to be set but proc_dointvec do not uses them. This commit fixes this by using proc_dointvec_minmax instead of proc_dointvec. Fixes: 7c0cca7c847e ("tty: ldisc: add sysctl to prevent autoloading of ldiscs") Cc: stable Signed-off-by: Nicolas Bouchinet Reviewed-by: Lin Feng Reviewed-by: Jiri Slaby Link: https://lore.kernel.org/r/20241112131357.49582-4-nicolas.bouchinet@clip-os.org Signed-off-by: Greg Kroah-Hartman

usb: cdc-acm: return correct error code on unsupported break

2024-01-25T23:35:53+00:00

[ Upstream commit 66aad7d8d3ec5a3a8ec2023841bcec2ded5f65c9 ] In ACM support for sending breaks to devices is optional. If a device says that it doenot support sending breaks, the host must respect that. Given the number of optional features providing tty operations for each combination is not practical and errors need to be returned dynamically if unsupported features are requested. In case a device does not support break, we want the tty layer to treat that like it treats drivers that statically cannot support sending a break. It ignores the inability and does nothing. This patch uses EOPNOTSUPP to indicate that. Signed-off-by: Oliver Neukum Fixes: 9e98966c7bb94 ("tty: rework break handling") Link: https://lore.kernel.org/r/20231207132639.18250-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

tty: use 'if' in send_break() instead of 'goto'

2024-01-25T23:35:53+00:00

[ Upstream commit 24f2cd019946fc2e88e632d2e24a34c2cc3f2be4 ] Now, the "jumped-over" code is simple enough to be put inside an 'if'. Do so to make it 'goto'-less. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20230919085156.1578-16-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 66aad7d8d3ec ("usb: cdc-acm: return correct error code on unsupported break") Signed-off-by: Sasha Levin

tty: don't check for signal_pending() in send_break()

2024-01-25T23:35:53+00:00

[ Upstream commit fd99392b643b824813df2edbaebe26a2136d31e6 ] msleep_interruptible() will check on its own. So no need to do the check in send_break() before calling the above. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20230919085156.1578-15-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 66aad7d8d3ec ("usb: cdc-acm: return correct error code on unsupported break") Signed-off-by: Sasha Levin

tty: early return from send_break() on TTY_DRIVER_HARDWARE_BREAK

2024-01-25T23:35:53+00:00

[ Upstream commit 66619686d187b4a6395316b7f39881e945dce4bc ] If the driver sets TTY_DRIVER_HARDWARE_BREAK, we leave ops->break_ctl() to the driver and return from send_break(). But we do it using a local variable and keep the code flowing through the end of the function. Instead, do 'return' immediately with the ops->break_ctl()'s return value. This way, we don't have to stuff the 'else' branch of the 'if' with the software break handling. And we can re-indent the function too. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20230919085156.1578-14-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman Stable-dep-of: 66aad7d8d3ec ("usb: cdc-acm: return correct error code on unsupported break") Signed-off-by: Sasha Levin

Merge tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2023-09-01T16:38:00+00:00

Pull tty/serial driver updates from Greg KH: "Here is the big set of tty and serial driver changes for 6.6-rc1. Lots of cleanups in here this cycle, and some driver updates. Short summary is: - Jiri's continued work to make the tty code and apis be a bit more sane with regards to modern kernel coding style and types - cpm_uart driver updates - n_gsm updates and fixes - meson driver updates - sc16is7xx driver updates - 8250 driver updates for different hardware types - qcom-geni driver fixes - tegra serial driver change - stm32 driver updates - synclink_gt driver cleanups - tty structure size reduction All of these have been in linux-next this week with no reported issues. The last bit of cleanups from Jiri and the tty structure size reduction came in last week, a bit late but as they were just style changes and size reductions, I figured they should get into this merge cycle so that others can work on top of them with no merge conflicts" * tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits) tty: shrink the size of struct tty_struct by 40 bytes tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw() tty: n_tty: extract ECHO_OP processing to a separate function tty: n_tty: unify counts to size_t tty: n_tty: use u8 for chars and flags tty: n_tty: simplify chars_in_buffer() tty: n_tty: remove unsigned char casts from character constants tty: n_tty: move newline handling to a separate function tty: n_tty: move canon handling to a separate function tty: n_tty: use MASK() for masking out size bits tty: n_tty: make n_tty_data::num_overrun unsigned tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun() tty: n_tty: use 'num' for writes' counts tty: n_tty: use output character directly tty: n_tty: make flow of n_tty_receive_buf_common() a bool Revert "tty: serial: meson: Add a earlycon for the T7 SoC" Documentation: devices.txt: Fix minors for ttyCPM* Documentation: devices.txt: Remove ttySIOC* Documentation: devices.txt: Remove ttyIOC* serial: 8250_bcm7271: improve bcm7271 8250 port ...

kill do_each_thread()

2023-08-21T20:46:25+00:00

Eric has pointed out that we still have 3 users of do_each_thread(). Change them to use for_each_process_thread() and kill this helper. There is a subtle change, after do_each_thread/while_each_thread g == t == &init_task, while after for_each_process_thread() they both point to nowhere, but this doesn't matter. > Why is for_each_process_thread() better than do_each_thread()? Say, for_each_process_thread() is rcu safe, do_each_thread() is not. And certainly for_each_process_thread(p, t) { do_something(p, t); } looks better than do_each_thread(p, t) { do_something(p, t); } while_each_thread(p, t); And again, there are only 3 users of this awkward helper left. It should have been killed years ago and in fact I thought it had already been killed. It uses while_each_thread() which needs some changes. Link: https://lkml.kernel.org/r/20230817163708.GA8248@redhat.com Signed-off-by: Oleg Nesterov Reviewed-by: Kees Cook Cc: "Christian Brauner (Microsoft)" Cc: Eric W. Biederman Cc: Jiri Slaby # tty/serial Signed-off-by: Andrew Morton

tty: use min() for size computation in iterate_tty_read()

2023-08-11T19:12:46+00:00

The computation is more obvious with min(). Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20230810091510.13006-27-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: switch size and count types in iterate_tty_read() to size_t

2023-08-11T19:12:46+00:00

ld->ops->read() returns ssize_t. copy_to_iter() returns size_t. So switch the variables ('size' and 'copied', respectively) to the corresponding types. This allows for use of min() in the next patch. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20230810091510.13006-26-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: use ssize_t for iterate_tty_read() returned type

2023-08-11T19:12:46+00:00

tty_read() is supposed to return ssize_t. It takes the return value from iterate_tty_read(). That currently returns int. On the top of that, iterate_tty_write() already returns ssize_t. So switch iterate_tty_read() to ssize_t too, so that all three are consistent. This means 'i' in tty_read() changes its type too. And while changing that, rename this generic 'i' to more dedicated 'ret'. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20230810091510.13006-25-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman