arm64: avoid multiple evaluation of ptr in get_user/put_user()
get_user() is defined as a function macro in arm64, and trace_get_user() calls it as followed: get_user(ch, ptr++); Since the second parameter occurs twice in the definition, 'ptr++' is unexpectedly evaluated twice and trace_get_user() will generate a bogus string from user-provided one. As a result, some ftrace sysfs operations, like "echo FUNCNAME > set_ftrace_filter," hit this case and eventually fail. This patch fixes the issue both in get_user() and put_user(). Signed-off-by: NAKASHI Takahiro <takahiro.akashi@linaro.org> [catalin.marinas@arm.com: added __user type annotation and s/optr/__p/] Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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