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