[RFC PATCH v1 8/9] arm64: Add unsafe_copy_from_user()
From: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org>
Date: 2026-04-27 17:19:12
Also in:
bpf, dmaengine, dri-devel, intel-gfx, kvm, linux-alpha, linux-arch, linux-arm-kernel, linux-efi, linux-fsdevel, linux-m68k, linux-media, linux-mips, linux-mm, linux-riscv, linux-s390, linux-serial, linux-sh, linux-sound, linux-spi, linux-staging, linux-um, linux-usb, linux-wireless, linuxppc-dev, lkml, loongarch, netdev, ocfs2-devel, rust-for-linux, sparclinux, xen-devel
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
At the time being, x86 and arm64 are missing unsafe_copy_from_user(). Add it. Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> --- arch/arm64/include/asm/uaccess.h | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 1e20ec91b56f..adfdb52cd82b 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h@@ -437,7 +437,7 @@ static inline void user_access_restore(unsigned long enabled) { } * We want the unsafe accessors to always be inlined and use * the error labels - thus the macro games. */ -#define unsafe_copy_loop(dst, src, len, type, label) \ +#define unsafe_put_loop(dst, src, len, type, label) \ while (len >= sizeof(type)) { \ unsafe_put_user(*(type *)(src),(type __user *)(dst),label); \ dst += sizeof(type); \
@@ -450,10 +450,29 @@ do { \ char __user *__ucu_dst = (_dst); \ const char *__ucu_src = (_src); \ size_t __ucu_len = (_len); \ - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \ - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \ - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \ - unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \ + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \ + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \ + unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ +} while (0) + +#define unsafe_get_loop(dst, src, len, type, label) \ + while (len >= sizeof(type)) { \ + unsafe_get_user(*(type __user *)(src),(type *)(dst),label); \ + dst += sizeof(type); \ + src += sizeof(type); \ + len -= sizeof(type); \ + } + +#define unsafe_copy_from_user(_dst,_src,_len,label) \ +do { \ + char *__ucu_dst = (_dst); \ + const char __user *__ucu_src = (_src); \ + size_t __ucu_len = (_len); \ + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label); \ + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label); \ + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label); \ + unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ } while (0) extern unsigned long __must_check __arch_clear_user(void __user *to, unsigned long n);
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2.49.0