[PATCH 1/5] vt: use copy_from/to_user instead of __get/put_user for scrnmap ioctls

[Adam Borowski]

Linus wants to get rid of these functions, and these uses are especially
egregious: they copy a big linear array element by element.

Signed-off-by: Adam Borowski <kilob...@angband.pl>
---
 drivers/tty/vt/consolemap.c | 31 +++++++------------------------
 1 file changed, 7 insertions(+), 24 deletions(-)

diff --git a/drivers/tty/vt/consolemap.c b/drivers/tty/vt/consolemap.c
index 1f6e17fc3fb0..1361f2a8b832 100644
--- a/drivers/tty/vt/consolemap.c
+++ b/drivers/tty/vt/consolemap.c
@@ -322,15 +322,13 @@ int con_set_trans_old(unsigned char __user * arg)
 {
        int i;
        unsigned short inbuf[E_TABSZ];
+       unsigned char ubuf[E_TABSZ];
 
-       if (!access_ok(VERIFY_READ, arg, E_TABSZ))
+       if (copy_from_user(ubuf, arg, E_TABSZ))
                return -EFAULT;
 
-       for (i = 0; i < E_TABSZ ; i++) {
-               unsigned char uc;
-               __get_user(uc, arg+i);
-               inbuf[i] = UNI_DIRECT_BASE | uc;
-       }
+       for (i = 0; i < E_TABSZ ; i++)
+               inbuf[i] = UNI_DIRECT_BASE | ubuf[i];
 
        console_lock();
        memcpy(translations[USER_MAP], inbuf, sizeof(inbuf));
@@ -345,9 +343,6 @@ int con_get_trans_old(unsigned char __user * arg)
        unsigned short *p = translations[USER_MAP];
        unsigned char outbuf[E_TABSZ];
 
-       if (!access_ok(VERIFY_WRITE, arg, E_TABSZ))
-               return -EFAULT;
-
        console_lock();
        for (i = 0; i < E_TABSZ ; i++)
        {
@@ -356,22 +351,16 @@ int con_get_trans_old(unsigned char __user * arg)
        }
        console_unlock();
 
-       for (i = 0; i < E_TABSZ ; i++)
-               __put_user(outbuf[i], arg+i);
-       return 0;
+       return copy_to_user(arg, outbuf, sizeof(outbuf)) ? -EFAULT : 0;
 }
 
 int con_set_trans_new(ushort __user * arg)
 {
-       int i;
        unsigned short inbuf[E_TABSZ];
 
-       if (!access_ok(VERIFY_READ, arg, E_TABSZ*sizeof(unsigned short)))
+       if (copy_from_user(inbuf, arg, sizeof(inbuf)))
                return -EFAULT;
 
-       for (i = 0; i < E_TABSZ ; i++)
-               __get_user(inbuf[i], arg+i);
-
        console_lock();
        memcpy(translations[USER_MAP], inbuf, sizeof(inbuf));
        update_user_maps();
@@ -381,19 +370,13 @@ int con_set_trans_new(ushort __user * arg)
 
 int con_get_trans_new(ushort __user * arg)
 {
-       int i;
        unsigned short outbuf[E_TABSZ];
 
-       if (!access_ok(VERIFY_WRITE, arg, E_TABSZ*sizeof(unsigned short)))
-               return -EFAULT;
-
        console_lock();
        memcpy(outbuf, translations[USER_MAP], sizeof(outbuf));
        console_unlock();
 
-       for (i = 0; i < E_TABSZ ; i++)
-               __put_user(outbuf[i], arg+i);
-       return 0;
+       return copy_to_user(arg, outbuf, sizeof(outbuf)) ? -EFAULT : 0;
 }
 
 /*
-- 
2.11.0