kernel/linux.git/include/linux/tty.h, branch linux-5.11.y

Commit 9bb48c82aced ("tty: implement write_iter") converted the tty

2021-01-25T20:08:07+00:00

layer to use write_iter. Fix the redirected_tty_write declaration also in n_tty and change the comparisons to use write_iter instead of write. [ Also moved the declaration of redirected_tty_write() to the proper location in a header file. The reason for the bug was the bogus extern declaration in n_tty.c silently not matching the changed definition in tty_io.c, and because it wasn't in a shared header file, there was no cross-checking of the declaration. Sami noticed because Clang's Control Flow Integrity checking ended up incidentally noticing the inconsistent declaration. - Linus ] Fixes: 9bb48c82aced ("tty: implement write_iter") Signed-off-by: Sami Tolvanen Signed-off-by: Linus Torvalds

tty: use const parameters in port-flag accessors

2020-12-09T14:27:42+00:00

Declare the port parameter to the flag-test accessors as const. This is currently mostly cosmetic as the accessors are already inlined. Suggested-by: Jiri Slaby Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20201202113942.27024-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: use assign_bit() in port-flag accessors

2020-12-09T14:26:31+00:00

Use the new assign_bit() wrapper in the port-flag accessors instead of open coding. Suggested-by: Jiri Slaby Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20201202113942.27024-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge 5.10-rc7 into tty-next

2020-12-07T09:19:31+00:00

We want the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman

tty: Fix ->session locking

2020-12-04T16:39:58+00:00

Currently, locking of ->session is very inconsistent; most places protect it using the legacy tty mutex, but disassociate_ctty(), __do_SAK(), tiocspgrp() and tiocgsid() don't. Two of the writers hold the ctrl_lock (because they already need it for ->pgrp), but __proc_set_tty() doesn't do that yet. On a PREEMPT=y system, an unprivileged user can theoretically abuse this broken locking to read 4 bytes of freed memory via TIOCGSID if tiocgsid() is preempted long enough at the right point. (Other things might also go wrong, especially if root-only ioctls are involved; I'm not sure about that.) Change the locking on ->session such that: - tty_lock() is held by all writers: By making disassociate_ctty() hold it. This should be fine because the same lock can already be taken through the call to tty_vhangup_session(). The tricky part is that we need to shorten the area covered by siglock to be able to take tty_lock() without ugly retry logic; as far as I can tell, this should be fine, since nothing in the signal_struct is touched in the `if (tty)` branch. - ctrl_lock is held by all writers: By changing __proc_set_tty() to hold the lock a little longer. - All readers that aren't holding tty_lock() hold ctrl_lock: By adding locking to tiocgsid() and __do_SAK(), and expanding the area covered by ctrl_lock in tiocspgrp(). Cc: stable@kernel.org Signed-off-by: Jann Horn Reviewed-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman

tty: Remove dead termiox code

2020-12-04T15:54:35+00:00

set_termiox() and the TCGETX handler bail out with -EINVAL immediately if ->termiox is NULL, but there are no code paths that can set ->termiox to a non-NULL pointer; and no such code paths seem to have existed since the termiox mechanism was introduced back in commit 1d65b4a088de ("tty: Add termiox") in v2.6.28. Similarly, no driver actually implements .set_termiox; and it looks like no driver ever has. Delete this dead code; but leave the definition of struct termiox in the UAPI headers intact. Signed-off-by: Jann Horn Link: https://lore.kernel.org/r/20201203020331.2394754-1-jannh@google.com Signed-off-by: Greg Kroah-Hartman

tty: tty_io: Move 'tty_sysctl_init's prototype to shared space

2020-11-06T09:49:27+00:00

Fixes the following W=1 kernel build warning(s): drivers/tty/tty_ldisc.c:883:6: warning: no previous prototype for ‘tty_sysctl_init’ [-Wmissing-prototypes] 883 | void tty_sysctl_init(void) | ^~~~~~~~~~~~~~~ Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Nick Holloway Cc: -- Cc: Marko Kohtala Cc: Bill Hawes Cc: "C. Scott Ananian" Cc: Russell King Cc: Andrew Morton Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20201104193549.4026187-5-lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman

gcc-10 warnings: fix low-hanging fruit

2020-05-04T16:16:37+00:00

Due to a bug-report that was compiler-dependent, I updated one of my machines to gcc-10. That shows a lot of new warnings. Happily they seem to be mostly the valid kind, but it's going to cause a round of churn for getting rid of them.. This is the really low-hanging fruit of removing a couple of zero-sized arrays in some core code. We have had a round of these patches before, and we'll have many more coming, and there is nothing special about these except that they were particularly trivial, and triggered more warnings than most. Signed-off-by: Linus Torvalds

serdev: ttyport: restore client ops on deregistration

2020-02-10T20:26:44+00:00

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 # 4.11 Reported-by: Loic Poulain Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20200210145730.22762-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

Merge 4.20-rc6 into tty-next

2018-12-10T09:17:45+00:00

We want the TTY changes in here as well. Signed-off-by: Greg Kroah-Hartman