| Message ID | 20210330172702.146909-2-tsbogend@alpha.franken.de (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | MIPS: Remove get_fs/set_fs | expand |
On Tue, Mar 30, 2021 at 07:26:58PM +0200, Thomas Bogendoerfer wrote: > Added __get/__put_kernel_nofault as preparation for removing > get/set_fs. For !CONFIG_EVA __get_user_common is simply defined to __get_kernel_common, which probably does the wrong thing here as it would allow access to user space addresses, won't it?
On Tue, Mar 30, 2021 at 07:48:35PM +0200, Christoph Hellwig wrote: > On Tue, Mar 30, 2021 at 07:26:58PM +0200, Thomas Bogendoerfer wrote: > > Added __get/__put_kernel_nofault as preparation for removing > > get/set_fs. > > For !CONFIG_EVA __get_user_common is simply defined to > __get_kernel_common, which probably does the wrong thing here > as it would allow access to user space addresses, won't it? it does, so I'm missing a copy_from_kernel_nofault_allowed() function, which only allows kernel access, right ? Thomas.
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h index d273a3857809..c5cab0b8f902 100644 --- a/arch/mips/include/asm/uaccess.h +++ b/arch/mips/include/asm/uaccess.h @@ -355,6 +355,18 @@ do { \ (val) = __gu_tmp.t; \ } +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + int __gu_err; \ + \ + __get_kernel_common(*((type *)(dst)), sizeof(type), \ + (__force type *)(src)); \ + if (unlikely(__gu_err)) \ + goto err_label; \ +} while (0) + #ifndef CONFIG_EVA #define __put_kernel_common(ptr, size) __put_user_common(ptr, size) #else @@ -483,6 +495,18 @@ do { \ extern void __put_user_unknown(void); +#define __put_kernel_nofault(dst, src, type, err_label) \ +do { \ + type __pu_val; \ + int __pu_err = 0; \ + \ + __pu_val = *(__force type *)(src); \ + __put_kernel_common(((type *)(dst)), sizeof(type)); \ + if (unlikely(__pu_err)) \ + goto err_label; \ +} while (0) + + /* * We're generating jump to subroutines which will be outside the range of * jump instructions
Added __get/__put_kernel_nofault as preparation for removing get/set_fs. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> --- arch/mips/include/asm/uaccess.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)