diff options
author | Jiri Slaby (SUSE) <jirislaby@kernel.org> | 2024-01-22 12:03:20 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-01-27 18:08:52 -0800 |
commit | d321cd13f6dca3c1b0e9e9735901fb5eee7a501c (patch) | |
tree | 23b990ec9ba2afa076b724747dc07c40b27a9442 /drivers/tty/vt/selection.c | |
parent | a0b8a1681254346010edd2f94e799fb6b6568cf1 (diff) |
tty: vt: push console lock from tioclinux() down to 2 functions
Avoid costly user copies under the console lock. So push the lock down
from tioclinux() to sel_loadlut() and set_vesa_blanking().
It is now obvious what is actually protected.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-7-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/vt/selection.c')
-rw-r--r-- | drivers/tty/vt/selection.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c index e172ede235a0..91d789c025c6 100644 --- a/drivers/tty/vt/selection.c +++ b/drivers/tty/vt/selection.c @@ -113,15 +113,22 @@ static inline int inword(const u32 c) * sel_loadlut() - load the LUT table * @lut: user table * - * Load the LUT table from user space. The caller must hold the console - * lock. Make a temporary copy so a partial update doesn't make a mess. + * Load the LUT table from user space. Make a temporary copy so a partial + * update doesn't make a mess. + * + * Locking: The console lock is acquired. */ int sel_loadlut(u32 __user *lut) { u32 tmplut[ARRAY_SIZE(inwordLut)]; + if (copy_from_user(tmplut, lut, sizeof(inwordLut))) return -EFAULT; + + console_lock(); memcpy(inwordLut, tmplut, sizeof(inwordLut)); + console_unlock(); + return 0; } |