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| author |   Christoph Hellwig <hch@lst.de> | 2020-06-08 21:35:01 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2020-06-09 09:39:16 -0700 |
| commit | fa94111d94354de76c47fea6e1187d1ee91e23a7 (patch) | |
| tree | 3b93b7e0348374ee7ed537642e205a567a64ce5f /arch | |
| parent | maccess: allow architectures to provide kernel probing directly (diff) | |
| download | linux-dev-fa94111d94354de76c47fea6e1187d1ee91e23a7.tar.xz linux-dev-fa94111d94354de76c47fea6e1187d1ee91e23a7.zip | |
x86: use non-set_fs based maccess routines
Provide arch_kernel_read and arch_kernel_write routines to implement the
maccess routines without messing with set_fs and without stac/clac that
opens up access to user space.
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-20-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/uaccess.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index d8f283b9a569..35b23b0311f5 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -523,5 +523,21 @@ do { \ unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label); \ } while (0) +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + int __kr_err; \ + \ + __get_user_size(*((type *)dst), (__force type __user *)src, \ + sizeof(type), __kr_err); \ + if (unlikely(__kr_err)) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ + __put_user_size(*((type *)(src)), (__force type __user *)(dst), \ + sizeof(type), err_label) + #endif /* _ASM_X86_UACCESS_H */ |