2023-08-08 22:37:41

by Günther Noack

[permalink] [raw]
Subject: [PATCH] TIOCSTI: Document CAP_SYS_ADMIN behaviour in Kconfig

Clarifies that the LEGACY_TIOCSTI setting is safe to turn off even
when running BRLTTY, as it was introduced in commit 690c8b804ad2
("TIOCSTI: always enable for CAP_SYS_ADMIN").

Signed-off-by: Günther Noack <[email protected]>
---
drivers/tty/Kconfig | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig
index 341abaed4ce..069de553127 100644
--- a/drivers/tty/Kconfig
+++ b/drivers/tty/Kconfig
@@ -164,6 +164,9 @@ config LEGACY_TIOCSTI
userspace depends on this functionality to continue operating
normally.

+ Processes which run with CAP_SYS_ADMIN, such as BRLTTY, can
+ use TIOCSTI even when this is set to N.
+
This functionality can be changed at runtime with the
dev.tty.legacy_tiocsti sysctl. This configuration option sets
the default value of the sysctl.
--
2.41.0