i2o: check return code from put_user()

Check return value of put_user() and return -EFAULT if it failed.
Original comment "We did a get user...so assuming mem is ok...is this
bad?" is incorrect because memory can be read only.

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/message/i2o/i2o_config.c b/drivers/message/i2o/i2o_config.c
index 4dd39a0..068ba07 100644 (file)
--- a/drivers/message/i2o/i2o_config.c
+++ b/drivers/message/i2o/i2o_config.c
@@ -111,9 +111,9 @@ static int i2o_cfg_gethrt(unsigned long arg)
 
        len = 8 + ((hrt->entry_len * hrt->num_entries) << 2);
 
-       /* We did a get user...so assuming mem is ok...is this bad? */
-       put_user(len, kcmd.reslen);
-       if (len > reslen)
+       if (put_user(len, kcmd.reslen))
+               ret = -EFAULT;
+       else if (len > reslen)
                ret = -ENOBUFS;
        else if (copy_to_user(kcmd.resbuf, (void *)hrt, len))
                ret = -EFAULT;
@@ -147,8 +147,9 @@ static int i2o_cfg_getlct(unsigned long arg)
        lct = (i2o_lct *) c->lct;
 
        len = (unsigned int)lct->table_size << 2;
-       put_user(len, kcmd.reslen);
-       if (len > reslen)
+       if (put_user(len, kcmd.reslen))
+               ret = -EFAULT;
+       else if (len > reslen)
                ret = -ENOBUFS;
        else if (copy_to_user(kcmd.resbuf, lct, len))
                ret = -EFAULT;
@@ -208,8 +209,9 @@ static int i2o_cfg_parms(unsigned long arg, unsigned int type)
                return -EAGAIN;
        }
 
-       put_user(len, kcmd.reslen);
-       if (len > reslen)
+       if (put_user(len, kcmd.reslen))
+               ret = -EFAULT;
+       else if (len > reslen)
                ret = -ENOBUFS;
        else if (copy_to_user(kcmd.resbuf, res, len))
                ret = -EFAULT;