On Sun, 6 Mar 2005, Yoichi Yuasa wrote:

> This patch converts verify_area to access_ok for include/asm-mips.
> 
Yeah, that's one of the few bits I had not done yet. Thank you for taking 
a look at that.

I don't believe your patch is correct though. See below for what I think 
is a better one.


> Yoichi
> 
> Signed-off-by: Yoichi Yuasa <[EMAIL PROTECTED]>
> 
> diff -urN -X dontdiff a-orig/include/asm-mips/uaccess.h 
> a/include/asm-mips/uaccess.h
> --- a-orig/include/asm-mips/uaccess.h Sat Mar  5 04:15:22 2005
> +++ a/include/asm-mips/uaccess.h      Sun Mar  6 15:51:02 2005
> @@ -254,13 +254,11 @@
>  ({                                                                   \
>       __typeof__(*(ptr)) __gu_val = 0;                                \
>       long __gu_addr;                                                 \
> -     long __gu_err;                                                  \
> +     long __gu_err = -EFAULT;                                        \
>                                                                       \
>       might_sleep();                                                  \
>       __gu_addr = (long) (ptr);                                       \
> -     __gu_err = verify_area(VERIFY_READ, (void *) __gu_addr, size);  \
> -                                                                     \
> -     if (likely(!__gu_err)) {                                        \
> +     if (access_ok(VERIFY_READ, (void *) __gu_addr, size)) {         \
>               switch (size) {                                         \
>               case 1: __get_user_asm("lb", __gu_err); break;          \
>               case 2: __get_user_asm("lh", __gu_err); break;          \

with this change, __gu_err will always be -EFAULT. With the original code 
it was either -EFAULT or 0 depending on the return value from verify_area. 
Same goes for the next hunk in your patch.

I believe a more correct patch would be this :

Signed-off-by: Jesper Juhl <[EMAIL PROTECTED]>

diff -up linux-2.6.11-mm1-orig/include/asm-mips/uaccess.h 
linux-2.6.11-mm1/include/asm-mips/uaccess.h
--- linux-2.6.11-mm1-orig/include/asm-mips/uaccess.h    2005-03-05 
00:39:40.000000000 +0100
+++ linux-2.6.11-mm1/include/asm-mips/uaccess.h 2005-03-07 00:49:24.000000000 
+0100
@@ -258,7 +258,8 @@ struct __large_struct { unsigned long bu
                                                                        \
        might_sleep();                                                  \
        __gu_addr = (long) (ptr);                                       \
-       __gu_err = verify_area(VERIFY_READ, (void *) __gu_addr, size);  \
+       __gu_err = access_ok(VERIFY_READ, (void *) __gu_addr, size)     \
+                               ? 0 : -EFAULT;                          \
                                                                        \
        if (likely(!__gu_err)) {                                        \
                switch (size) {                                         \
@@ -353,7 +354,8 @@ extern void __get_user_unknown(void);
        might_sleep();                                                  \
        __pu_val = (x);                                                 \
        __pu_addr = (long) (ptr);                                       \
-       __pu_err = verify_area(VERIFY_WRITE, (void *) __pu_addr, size); \
+       __pu_err = access_ok(VERIFY_WRITE, (void *) __pu_addr, size)    \
+                               ? 0 : -EFAULT;                          \
                                                                        \
        if (likely(!__pu_err)) {                                        \
                switch (size) {                                         \




It preserves the exact behaviour of the original.


-- 
Jesper 


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