Move stack parameters for sed_ioctl to prevent oversized stack with CONFIG_KASAN

When CONFIG_KASAN is enabled, compilation fails:

block/sed-opal.c: In function 'sed_ioctl':
block/sed-opal.c:2447:1: error: the frame size of 2256 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

Moved all the ioctl structures off the stack and dynamically allocate
using _IOC_SIZE()

Fixes: 455a7b238cd6 ("block: Add Sed-opal library")

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Scott Bauer <scott.bauer@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 46 insertions, 87 deletions

diff --git a/block/sed-opal.c b/block/sed-opal.c
index bf1406e5159b..e95b8a57053d 100644
--- a/block/sed-opal.c
+++ b/block/sed-opal.c
@@ -2344,9 +2344,10 @@ bool opal_unlock_from_suspend(struct opal_dev *dev)
 }
 EXPORT_SYMBOL(opal_unlock_from_suspend);
 
-int sed_ioctl(struct opal_dev *dev, unsigned int cmd, unsigned long ptr)
+int sed_ioctl(struct opal_dev *dev, unsigned int cmd, void __user *arg)
 {
-        void __user *arg = (void __user *)ptr;
+        void *p;
+        int ret = -ENOTTY;
 
         if (!capable(CAP_SYS_ADMIN))
                 return -EACCES;
@@ -2355,94 +2356,52 @@ int sed_ioctl(struct opal_dev *dev, unsigned int cmd, unsigned long ptr)
                 return -ENOTSUPP;
         }
 
-        switch (cmd) {
-        case IOC_OPAL_SAVE: {
-                struct opal_lock_unlock lk_unlk;
-
-                if (copy_from_user(&lk_unlk, arg, sizeof(lk_unlk)))
-                        return -EFAULT;
-                return opal_save(dev, &lk_unlk);
-        }
-        case IOC_OPAL_LOCK_UNLOCK: {
-                struct opal_lock_unlock lk_unlk;
-
-                if (copy_from_user(&lk_unlk, arg, sizeof(lk_unlk)))
-                        return -EFAULT;
-                return opal_lock_unlock(dev, &lk_unlk);
-        }
-        case IOC_OPAL_TAKE_OWNERSHIP: {
-                struct opal_key opal_key;
-
-                if (copy_from_user(&opal_key, arg, sizeof(opal_key)))
-                        return -EFAULT;
-                return opal_take_ownership(dev, &opal_key);
-        }
-        case IOC_OPAL_ACTIVATE_LSP: {
-                struct opal_lr_act opal_lr_act;
-
-                if (copy_from_user(&opal_lr_act, arg, sizeof(opal_lr_act)))
-                        return -EFAULT;
-                return opal_activate_lsp(dev, &opal_lr_act);
-        }
-        case IOC_OPAL_SET_PW: {
-                struct opal_new_pw opal_pw;
-
-                if (copy_from_user(&opal_pw, arg, sizeof(opal_pw)))
-                        return -EFAULT;
-                return opal_set_new_pw(dev, &opal_pw);
-        }
-        case IOC_OPAL_ACTIVATE_USR: {
-                struct opal_session_info session;
-
-                if (copy_from_user(&session, arg, sizeof(session)))
-                        return -EFAULT;
-                return opal_activate_user(dev, &session);
-        }
-        case IOC_OPAL_REVERT_TPR: {
-                struct opal_key opal_key;
-
-                if (copy_from_user(&opal_key, arg, sizeof(opal_key)))
-                        return -EFAULT;
-                return opal_reverttper(dev, &opal_key);
-        }
-        case IOC_OPAL_LR_SETUP: {
-                struct opal_user_lr_setup lrs;
+        p = memdup_user(arg,  _IOC_SIZE(cmd));
+        if (IS_ERR(p))
+                return PTR_ERR(p);
 
-                if (copy_from_user(&lrs, arg, sizeof(lrs)))
-                        return -EFAULT;
-                return opal_setup_locking_range(dev, &lrs);
-        }
-        case IOC_OPAL_ADD_USR_TO_LR: {
-                struct opal_lock_unlock lk_unlk;
-
-                if (copy_from_user(&lk_unlk, arg, sizeof(lk_unlk)))
-                        return -EFAULT;
-                return opal_add_user_to_lr(dev, &lk_unlk);
-        }
-        case IOC_OPAL_ENABLE_DISABLE_MBR: {
-                struct opal_mbr_data mbr;
-
-                if (copy_from_user(&mbr, arg, sizeof(mbr)))
-                        return -EFAULT;
-                return opal_enable_disable_shadow_mbr(dev, &mbr);
-        }
-        case IOC_OPAL_ERASE_LR: {
-                struct opal_session_info session;
-
-                if (copy_from_user(&session, arg, sizeof(session)))
-                        return -EFAULT;
-                return opal_erase_locking_range(dev, &session);
-        }
-        case IOC_OPAL_SECURE_ERASE_LR: {
-                struct opal_session_info session;
-
-                if (copy_from_user(&session, arg, sizeof(session)))
-                        return -EFAULT;
-                return opal_secure_erase_locking_range(dev, &session);
-        }
+        switch (cmd) {
+        case IOC_OPAL_SAVE:
+                ret = opal_save(dev, p);
+                break;
+        case IOC_OPAL_LOCK_UNLOCK:
+                ret = opal_lock_unlock(dev, p);
+                break;
+        case IOC_OPAL_TAKE_OWNERSHIP:
+                ret = opal_take_ownership(dev, p);
+                break;
+        case IOC_OPAL_ACTIVATE_LSP:
+                ret = opal_activate_lsp(dev, p);
+                break;
+        case IOC_OPAL_SET_PW:
+                ret = opal_set_new_pw(dev, p);
+                break;
+        case IOC_OPAL_ACTIVATE_USR:
+                ret = opal_activate_user(dev, p);
+                break;
+        case IOC_OPAL_REVERT_TPR:
+                ret = opal_reverttper(dev, p);
+                break;
+        case IOC_OPAL_LR_SETUP:
+                ret = opal_setup_locking_range(dev, p);
+                break;
+        case IOC_OPAL_ADD_USR_TO_LR:
+                ret = opal_add_user_to_lr(dev, p);
+                break;
+        case IOC_OPAL_ENABLE_DISABLE_MBR:
+                ret = opal_enable_disable_shadow_mbr(dev, p);
+                break;
+        case IOC_OPAL_ERASE_LR:
+                ret = opal_erase_locking_range(dev, p);
+                break;
+        case IOC_OPAL_SECURE_ERASE_LR:
+                ret = opal_secure_erase_locking_range(dev, p);
+                break;
         default:
                 pr_warn("No such Opal Ioctl %u\n", cmd);
         }
-        return -ENOTTY;
+
+        kfree(p);
+        return ret;
 }
 EXPORT_SYMBOL_GPL(sed_ioctl);