From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- arch/x86/lib/usercopy.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 arch/x86/lib/usercopy.c (limited to 'arch/x86/lib/usercopy.c') diff --git a/arch/x86/lib/usercopy.c b/arch/x86/lib/usercopy.c new file mode 100644 index 000000000..3f435d7fc --- /dev/null +++ b/arch/x86/lib/usercopy.c @@ -0,0 +1,38 @@ +/* + * User address space access functions. + * + * For licencing details see kernel-base/COPYING + */ + +#include +#include + +#include + +/* + * We rely on the nested NMI work to allow atomic faults from the NMI path; the + * nested NMI paths are careful to preserve CR2. + */ +unsigned long +copy_from_user_nmi(void *to, const void __user *from, unsigned long n) +{ + unsigned long ret; + + if (__range_not_ok(from, n, TASK_SIZE)) + return n; + + if (!nmi_uaccess_okay()) + return n; + + /* + * Even though this function is typically called from NMI/IRQ context + * disable pagefaults so that its behaviour is consistent even when + * called form other contexts. + */ + pagefault_disable(); + ret = __copy_from_user_inatomic(to, from, n); + pagefault_enable(); + + return ret; +} +EXPORT_SYMBOL_GPL(copy_from_user_nmi); -- cgit v1.2.3