[mirror_ubuntu-bionic-kernel.git] / lib / usercopy.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/uaccess.h>

/* out-of-line parts */

#ifndef INLINE_COPY_FROM_USER
unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
{
	unsigned long res = n;
	might_fault();
	if (likely(access_ok(VERIFY_READ, from, n))) {
		kasan_check_write(to, n);
		res = raw_copy_from_user(to, from, n);
	}
	if (unlikely(res))
		memset(to + (n - res), 0, res);
	return res;
}
EXPORT_SYMBOL(_copy_from_user);
#endif

#ifndef INLINE_COPY_TO_USER
unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n)
{
	might_fault();
	if (likely(access_ok(VERIFY_WRITE, to, n))) {
		kasan_check_read(from, n);
		n = raw_copy_to_user(to, from, n);
	}
	return n;
}
EXPORT_SYMBOL(_copy_to_user);
#endif
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
d597580d AV	2	#include <linux/uaccess.h>
	3
	4	/* out-of-line parts */
	5
	6	#ifndef INLINE_COPY_FROM_USER
	7	unsigned long _copy_from_user(void to, const void __user from, unsigned long n)
	8	{
	9	unsigned long res = n;
9c5f6908 AV	10	might_fault();
	11	if (likely(access_ok(VERIFY_READ, from, n))) {
	12	kasan_check_write(to, n);
d597580d	13	res = raw_copy_from_user(to, from, n);
9c5f6908	14	}
d597580d AV	15	if (unlikely(res))
	16	memset(to + (n - res), 0, res);
	17	return res;
	18	}
	19	EXPORT_SYMBOL(_copy_from_user);
	20	#endif
	21
	22	#ifndef INLINE_COPY_TO_USER
39993d6d	23	unsigned long _copy_to_user(void __user to, const void from, unsigned long n)
d597580d	24	{
9c5f6908 AV	25	might_fault();
	26	if (likely(access_ok(VERIFY_WRITE, to, n))) {
	27	kasan_check_read(from, n);
d597580d	28	n = raw_copy_to_user(to, from, n);
9c5f6908	29	}
d597580d AV	30	return n;
	31	}
	32	EXPORT_SYMBOL(_copy_to_user);
	33	#endif