[PATCH 07/17] vt: keyboard, union perm checks in vt_do_kdsk_ioctl

From: Jiri Slaby
Date: Thu Oct 29 2020 - 07:33:36 EST


Do the permission check on a single place. That is where perm is really
checked.

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/tty/vt/keyboard.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index c1709b8dbb52..823df9bb52b1 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -2004,16 +2004,13 @@ int vt_do_kdsk_ioctl(int cmd, struct kbentry __user *user_kbe, int perm,
if (copy_from_user(&kbe, user_kbe, sizeof(struct kbentry)))
return -EFAULT;

- if (!capable(CAP_SYS_TTY_CONFIG))
- perm = 0;
-
switch (cmd) {
case KDGKBENT:
return put_user(vt_kdgkbent(kb->kbdmode, kbe.kb_index,
kbe.kb_table),
&user_kbe->kb_value);
case KDSKBENT:
- if (!perm)
+ if (!perm || !capable(CAP_SYS_TTY_CONFIG))
return -EPERM;
return vt_kdskbent(kb->kbdmode, kbe.kb_index, kbe.kb_table,
kbe.kb_value);
--
2.29.1