Re: [PATCH 2/3] kernel.h: add u64_to_user_ptr()

2016-04-20 Joe Perches joe@perches.com:

On Wed, 2016-04-20 at 16:18 -0300, Gustavo Padovan wrote:

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From: Gustavo Padovan gustavo.padovan@collabora.co.uk

This function had copies in 3 different files. Unify them in kernel.h.

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diff --git a/include/linux/kernel.h b/include/linux/kernel.h

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@@ -53,6 +53,12 @@

#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))   +static inline void __user *u64_to_user_ptr(u64 address) +{

• typecheck(u64, address);
• return (void __user *)(uintptr_t)address;

+}

This won't work because by the time address is checked address is already u64

This would need to be something like

#define u64_to_user_ptr(x) \ ({ \ typecheck(u64, x); \ u64_to_user_ptr(x); \ })

Indeed, thanks for noting and for the suggestion.

Gustavo