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efivars spinlock fix

PATCH New [email protected] 1 participant 1 message Jul 23, 2001

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PATCH 1/1 efivars spinlock fix

The patch below fixes a couple potential failures in the efivars module. First, it was calling kmalloc, which could sleep, while holding a spinlock. Second, it would fail to free allocated memory if copy_from_user() failed.

David, please apply.

Thanks,
Matt

--
Matt Domsch
Sr. Software Engineer
Dell Linux Solutions
www.dell.com/linux
#2 Linux Server provider with 17% in the US and 14% Worldwide (IDC)! #3 Unix provider with 18% in the US (Dataquest)!

arch/ia64/kernel/efivars.c renamed from arch/ia64/kernel/efivars.c.orig +2 -3
@@ -276,21 +276,20 @@
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	spin_lock(&efivars_lock);
 	MOD_INC_USE_COUNT;
 
 	var_data = kmalloc(size, GFP_KERNEL);
 	if (!var_data) {
 		MOD_DEC_USE_COUNT;
-		spin_unlock(&efivars_lock);
 		return -ENOMEM;
 	}
 	if (copy_from_user(var_data, buffer, size)) {
 		MOD_DEC_USE_COUNT;
-		spin_unlock(&efivars_lock);
+		kfree(var_data);
 		return -EFAULT;
 	}
 
+	spin_lock(&efivars_lock);
 
 	/* Since the data ptr we've currently got is probably for
 	   a different variable find the right variable.