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man/man2const/TIOCLINUX.2const: Document CAP_SYS_ADMIN requirement for TIOCL_SETSEL modes

PATCH In review Günther Noack 2 participants 2 messages May 2, 2025 Man-pages: manual pages for Linux -- Sections 2, 3, 4, 5, and 7

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Günther Noack

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PATCH v2 1/1 man/man2const/TIOCLINUX.2const: Document CAP_SYS_ADMIN requirement for TIOCL_SETSEL modes

CAP_SYS_ADMIN was previously required for the entire TIOCL_SETSEL subcode, but is now only needed for a subset of the selection modes, since linux.git 2f83e38a095f (2025-01-13; "tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMIN").

The CAP_SYS_ADMIN requirement for TIOCL_SELMOUSEREPORT was further corrected in linux.git ee6a44da3c87 (2025-04-11; "tty: Require CAP_SYS_ADMIN for all usages of TIOCL_SELMOUSEREPORT").

Admittedly, there are kernels where CAP_SYS_ADMIN was briefly not required for TIOCL_SELMOUSEREPORT, even after Linux v6.7, but this was a mistake which is now fixed in all up-to-date stable kernels. Therefore, we still document CAP_SYS_ADMIN as required "since Linux 6.7" in this case.

Link <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=2f83e38a095f8bf7c6029883d894668b03b9bd93>
Link <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=ee6a44da3c87cf64d67dd02be8c0127a5bf56175>
Signed-off-by Günther Noack <[email protected]>
---
 man/man2const/TIOCLINUX.2const | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)
man/man2const/TIOCLINUX.2const +14 -2
index 61f1c596d..b98a0202b 100644
@@ -72,18 +72,30 @@ may be one of the following operations:
 Select character-by-character.
 The indicated screen characters are highlighted
 and saved in a kernel buffer.
+.IP
+Since Linux 6.7, using this selection mode requires the
+.B CAP_SYS_ADMIN
+capability.
 .TP
 .B TIOCL_SELWORD
 Select word-by-word,
 expanding the selection outwards to align with word boundaries.
 The indicated screen characters are highlighted
 and saved in a kernel buffer.
+.IP
+Since Linux 6.7, using this selection mode requires the
+.B CAP_SYS_ADMIN
+capability.
 .TP
 .B TIOCL_SELLINE
 Select line-by-line,
 expanding the selection outwards to select full lines.
 The indicated screen characters are highlighted
 and saved in a kernel buffer.
+.IP
+Since Linux 6.7, using this selection mode requires the
+.B CAP_SYS_ADMIN
+capability.
 .TP
 .B TIOCL_SELPOINTER
 Show the pointer at position

@@ -118,11 +130,11 @@ If mouse reporting is not enabled for the terminal,
 this operation yields an
 .B EINVAL
 error.
-.RE
 .IP
-Since Linux 6.7, using this subcode requires the
+Since Linux 6.7, using this selection mode requires the
 .B CAP_SYS_ADMIN
 capability.
+.RE
 .TP
 .BR subcode = TIOCL_PASTESEL
 Paste selection.
Signature · 1 line
2.49.0
maintainer
#1 lore raw

Hi Günther,

Quoted 15 lines · Günther Noack

CAP_SYS_ADMIN was previously required for the entire TIOCL_SETSEL subcode, but is now only needed for a subset of the selection modes, since linux.git 2f83e38a095f (2025-01-13; "tty: Permit some TIOCL_SETSEL modes without CAP_SYS_ADMIN").

The CAP_SYS_ADMIN requirement for TIOCL_SELMOUSEREPORT was further corrected in linux.git ee6a44da3c87 (2025-04-11; "tty: Require CAP_SYS_ADMIN for all usages of TIOCL_SELMOUSEREPORT").

Admittedly, there are kernels where CAP_SYS_ADMIN was briefly not required for TIOCL_SELMOUSEREPORT, even after Linux v6.7, but this was a mistake which is now fixed in all up-to-date stable kernels. Therefore, we still document CAP_SYS_ADMIN as required "since Linux 6.7" in this case.

Quoted 3 lines
Link <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=2f83e38a095f8bf7c6029883d894668b03b9bd93>
Link <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=ee6a44da3c87cf64d67dd02be8c0127a5bf56175>
Signed-off-by Günther Noack <[email protected]>

Thanks! I've applied the patch.
<https://www.alejandro-colomar.es/src/alx/linux/man-pages/man-pages.git/commit/?h=contrib&id=5889aa978ddc93d31d3c48c29899761ebde3f53d>

Have a lovely day!
Alex

Quoted 56 lines
---
 man/man2const/TIOCLINUX.2const | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)
man/man2const/TIOCLINUX.2const +14 -2
index 61f1c596d..b98a0202b 100644
@@ -72,18 +72,30 @@ may be one of the following operations:
 Select character-by-character.
 The indicated screen characters are highlighted
 and saved in a kernel buffer.
+.IP
+Since Linux 6.7, using this selection mode requires the
+.B CAP_SYS_ADMIN
+capability.
 .TP
 .B TIOCL_SELWORD
 Select word-by-word,
 expanding the selection outwards to align with word boundaries.
 The indicated screen characters are highlighted
 and saved in a kernel buffer.
+.IP
+Since Linux 6.7, using this selection mode requires the
+.B CAP_SYS_ADMIN
+capability.
 .TP
 .B TIOCL_SELLINE
 Select line-by-line,
 expanding the selection outwards to select full lines.
 The indicated screen characters are highlighted
 and saved in a kernel buffer.
+.IP
+Since Linux 6.7, using this selection mode requires the
+.B CAP_SYS_ADMIN
+capability.
 .TP
 .B TIOCL_SELPOINTER
 Show the pointer at position

@@ -118,11 +130,11 @@ If mouse reporting is not enabled for the terminal,
 this operation yields an
 .B EINVAL
 error.
-.RE
 .IP
-Since Linux 6.7, using this subcode requires the
+Since Linux 6.7, using this selection mode requires the
 .B CAP_SYS_ADMIN
 capability.
+.RE
 .TP
 .BR subcode = TIOCL_PASTESEL
 Paste selection.
Signature · 1 line
2.49.0
Signature · 1 line
<https://www.alejandro-colomar.es/>