Message ID | 1399360312-13843-1-git-send-email-a.ryabinin@samsung.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
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.ryabinin@samsung.com> > Reviewed-by: Nicolas Pitre <nico@linaro.org> > Cc: stable@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: stable@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 >
On 05/07/14 00:13, Nicolas Pitre wrote: > Please push this patch into Russell's patch system. > > Thanks. > Done - http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8051/1 Thanks.
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))) { \