On Tue, 6 May 2014, Andrey Ryabinin wrote: > According to arm procedure call standart r2 register is call-cloberred. > So after the result of x expression was put into r2 any following > function call in p may overwrite r2. To fix this, the result of p > expression must be saved to the temporary variable before the > assigment x expression to __r2. > > Signed-off-by: Andrey Ryabinin <a.ryabi...@samsung.com> > Reviewed-by: Nicolas Pitre <n...@linaro.org> > Cc: sta...@vger.kernel.org
Please push this patch into Russell's patch system. Thanks. > --- > Since v1: > - tmp_p variable renamed to __tmp_p > - added Reviewed-by tag > - added Cc: sta...@vger.kernel.org > > arch/arm/include/asm/uaccess.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h > index 12c3a5d..75d9579 100644 > --- a/arch/arm/include/asm/uaccess.h > +++ b/arch/arm/include/asm/uaccess.h > @@ -171,8 +171,9 @@ extern int __put_user_8(void *, unsigned long long); > #define __put_user_check(x,p) > \ > ({ \ > unsigned long __limit = current_thread_info()->addr_limit - 1; \ > + const typeof(*(p)) __user *__tmp_p = (p); \ > register const typeof(*(p)) __r2 asm("r2") = (x); \ > - register const typeof(*(p)) __user *__p asm("r0") = (p);\ > + register const typeof(*(p)) __user *__p asm("r0") = __tmp_p; \ > register unsigned long __l asm("r1") = __limit; \ > register int __e asm("r0"); \ > switch (sizeof(*(__p))) { \ > -- > 1.8.5.5 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/