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a0e94598e6
Destination is a kernel pointer and source - a userland one
in _copy_from_user(); _copy_to_user() is the other way round.
Fixes: d597580d37 ("generic ...copy_..._user primitives")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
34 lines
764 B
C
34 lines
764 B
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/uaccess.h>
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/* out-of-line parts */
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#ifndef INLINE_COPY_FROM_USER
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unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
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{
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unsigned long res = n;
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might_fault();
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if (likely(access_ok(VERIFY_READ, from, n))) {
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kasan_check_write(to, n);
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res = raw_copy_from_user(to, from, n);
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}
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if (unlikely(res))
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memset(to + (n - res), 0, res);
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return res;
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}
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EXPORT_SYMBOL(_copy_from_user);
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#endif
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#ifndef INLINE_COPY_TO_USER
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unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n)
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{
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might_fault();
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if (likely(access_ok(VERIFY_WRITE, to, n))) {
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kasan_check_read(from, n);
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n = raw_copy_to_user(to, from, n);
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}
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return n;
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}
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EXPORT_SYMBOL(_copy_to_user);
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#endif
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