kernel/drivers/tty/vt, branch linux-6.9.y

tty: add the option to have a tty reject a new ldisc

2024-06-27T11:52:18Z

[ Upstream commit 6bd23e0c2bb6c65d4f5754d1456bc9a4427fc59b ] ... and use it to limit the virtual terminals to just N_TTY. They are kind of special, and in particular, the "con_write()" routine violates the "writes cannot sleep" rule that some ldiscs rely on. This avoids the BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659 when N_GSM has been attached to a virtual console, and gsmld_write() calls con_write() while holding a spinlock, and con_write() then tries to get the console lock. Tested-by: Tetsuo Handa Cc: Jiri Slaby Cc: Andrew Morton Cc: Daniel Starke Reported-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=dbac96d8e73b61aa559c Signed-off-by: Linus Torvalds Link: https://lore.kernel.org/r/20240423163339.59780-1-torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

Merge tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2024-03-21T19:44:10Z

Pull tty / serial driver updates from Greg KH: "Here is the big set of TTY/Serial driver updates and cleanups for 6.9-rc1. Included in here are: - more tty cleanups from Jiri - loads of 8250 driver cleanups from Andy - max310x driver updates - samsung serial driver updates - uart_prepare_sysrq_char() updates for many drivers - platform driver remove callback void cleanups - stm32 driver updates - other small tty/serial driver updates All of these have been in linux-next for a long time with no reported issues" * tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits) dt-bindings: serial: stm32: add power-domains property serial: 8250_dw: Replace ACPI device check by a quirk serial: Lock console when calling into driver before registration serial: 8250_uniphier: Switch to use uart_read_port_properties() serial: 8250_tegra: Switch to use uart_read_port_properties() serial: 8250_pxa: Switch to use uart_read_port_properties() serial: 8250_omap: Switch to use uart_read_port_properties() serial: 8250_of: Switch to use uart_read_port_properties() serial: 8250_lpc18xx: Switch to use uart_read_port_properties() serial: 8250_ingenic: Switch to use uart_read_port_properties() serial: 8250_dw: Switch to use uart_read_port_properties() serial: 8250_bcm7271: Switch to use uart_read_port_properties() serial: 8250_bcm2835aux: Switch to use uart_read_port_properties() serial: 8250_aspeed_vuart: Switch to use uart_read_port_properties() serial: port: Introduce a common helper to read properties serial: core: Add UPIO_UNKNOWN constant for unknown port type serial: core: Move struct uart_port::quirks closer to possible values serial: sh-sci: Call sci_serial_{in,out}() directly serial: core: only stop transmit when HW fifo is empty serial: pch: Use uart_prepare_sysrq_char(). ...

vt: fix unicode buffer corruption when deleting characters

2024-03-02T22:09:04Z

This is the same issue that was fixed for the VGA text buffer in commit 39cdb68c64d8 ("vt: fix memory overlapping when deleting chars in the buffer"). The cure is also the same i.e. replace memcpy() with memmove() due to the overlaping buffers. Signed-off-by: Nicolas Pitre Fixes: 81732c3b2fed ("tty vt: Fix line garbage in virtual console on command line edition") Cc: stable Link: https://lore.kernel.org/r/sn184on2-3p0q-0qrq-0218-895349s4753o@syhkavp.arg Signed-off-by: Greg Kroah-Hartman

tty/vt: Corrected doc of vc_sanitize_unicode(), vc_translate_unicode()

2024-02-17T16:44:46Z

Corrected the doc of vc_sanitize_unicode() and vc_translate_unicode(), tightly coupled functions which parse UTF-8 byte sequences. 1. Desc. of @rescan corresponded to the meaning of the return value -1. Corrected + added "Return:" section. 2. Replaced the ambiguous "character" with "code point" or "byte". Signed-off-by: Roman Žilka Link: https://lore.kernel.org/r/bee9faa8-0ea7-4411-bf77-3cb2e06385c7@gmail.com Signed-off-by: Greg Kroah-Hartman

tty: vt: decrypt magic constants in vc_is_control()

2024-02-06T14:37:39Z

0x0d00ff81 and 0x0800f501 are bitmasks of ASCII characters. Spell them explicitly using BIT() + ASCII constants. GENMASK() is used for the 9-bit range in CTRL_ACTION. This also modifies the 'if' checking if the masks should be applied. >From a "random" ' ' to the actual size of the bitmasks' type. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20240202065608.14019-23-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: vt: use ASCII enum constants in vt_console_print()

2024-02-06T14:37:39Z

There are still numbers used for ASCII characters in vt_console_print(). As we have an ASCII enum now, use the constant names from the enum instead. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20240202065608.14019-22-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: vt: use switch+case in the ESgetpars case

2024-02-06T14:37:39Z

To be uniform in the 'c' handling, use switch-case (with ranges) even in the ESgetpars case in do_con_trol(). Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20240202065608.14019-21-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: vt: use switch+case in the ESnonstd case

2024-02-06T14:37:39Z

To be uniform in the 'c' handling, use switch-case (with ranges) even in the ESnonstd case in do_con_trol(). Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20240202065608.14019-20-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: vt: add new helper for reseting vc parameters

2024-02-06T14:37:39Z

The code to reset the vc parameter parsing is repeated on two locations. Create a helper vc_reset_params() and use it on both of them. And instead of a 'for' loop to clear the array of parameters, use simpler memset(). Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20240202065608.14019-19-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: vt: handle CSI+[ inside preexisting switch-case

2024-02-06T14:37:39Z

In do_con_trol()'s ESsquare case, there is already a switch (c). It is preceded by an 'if (c == '[')'. Despite this 'if' handles a state transition and not a modifier, move it as one of the switch cases. This makes all the 'c' decision making more obvious there. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20240202065608.14019-18-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman