From 69d5ffdaad7b77b97229b55c36afb20e5bebd29e Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 18 Jun 2009 21:48:19 +0200 Subject: [PATCH] x86: convert termios.h to the asm-generic version This patch turned out more controversial than expected and may get dropped in the future. I'm including it for reference anyway. The user_termio_to_kernel_termios and kernel_termios_to_user_termio functions on x86 are lacking error checking from get_user and are not portable to big-endian systems, so the asm-generic header has to differ in this regard. Signed-off-by: Arnd Bergmann LKML-Reference: Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/termios.h | 86 +++++++++++++++++++++++++--------- 1 file changed, 63 insertions(+), 23 deletions(-) diff --git a/arch/x86/include/asm/termios.h b/arch/x86/include/asm/termios.h index c4ee8056baca..d0922adc56d4 100644 --- a/arch/x86/include/asm/termios.h +++ b/arch/x86/include/asm/termios.h @@ -1,5 +1,12 @@ -#ifndef _ASM_X86_TERMIOS_H -#define _ASM_X86_TERMIOS_H +#ifndef _ASM_GENERIC_TERMIOS_H +#define _ASM_GENERIC_TERMIOS_H +/* + * Most architectures have straight copies of the x86 code, with + * varying levels of bug fixes on top. Usually it's a good idea + * to use this generic version instead, but be careful to avoid + * ABI changes. + * New architectures should not provide their own version. + */ #include #include @@ -54,37 +61,57 @@ struct termio { /* * Translate a "termio" structure into a "termios". Ugh. */ -#define SET_LOW_TERMIOS_BITS(termios, termio, x) { \ - unsigned short __tmp; \ - get_user(__tmp,&(termio)->x); \ - *(unsigned short *) &(termios)->x = __tmp; \ -} - static inline int user_termio_to_kernel_termios(struct ktermios *termios, - struct termio __user *termio) + const struct termio __user *termio) { - SET_LOW_TERMIOS_BITS(termios, termio, c_iflag); - SET_LOW_TERMIOS_BITS(termios, termio, c_oflag); - SET_LOW_TERMIOS_BITS(termios, termio, c_cflag); - SET_LOW_TERMIOS_BITS(termios, termio, c_lflag); - get_user(termios->c_line, &termio->c_line); - return copy_from_user(termios->c_cc, termio->c_cc, NCC); + unsigned short tmp; + + if (get_user(tmp, &termio->c_iflag) < 0) + goto fault; + termios->c_iflag = (0xffff0000 & termios->c_iflag) | tmp; + + if (get_user(tmp, &termio->c_oflag) < 0) + goto fault; + termios->c_oflag = (0xffff0000 & termios->c_oflag) | tmp; + + if (get_user(tmp, &termio->c_cflag) < 0) + goto fault; + termios->c_cflag = (0xffff0000 & termios->c_cflag) | tmp; + + if (get_user(tmp, &termio->c_lflag) < 0) + goto fault; + termios->c_lflag = (0xffff0000 & termios->c_lflag) | tmp; + + if (get_user(termios->c_line, &termio->c_line) < 0) + goto fault; + + if (copy_from_user(termios->c_cc, termio->c_cc, NCC) != 0) + goto fault; + + return 0; + + fault: + return -EFAULT; } /* * Translate a "termios" structure into a "termio". Ugh. */ static inline int kernel_termios_to_user_termio(struct termio __user *termio, - struct ktermios *termios) + struct ktermios *termios) { - put_user((termios)->c_iflag, &(termio)->c_iflag); - put_user((termios)->c_oflag, &(termio)->c_oflag); - put_user((termios)->c_cflag, &(termio)->c_cflag); - put_user((termios)->c_lflag, &(termio)->c_lflag); - put_user((termios)->c_line, &(termio)->c_line); - return copy_to_user((termio)->c_cc, (termios)->c_cc, NCC); + if (put_user(termios->c_iflag, &termio->c_iflag) < 0 || + put_user(termios->c_oflag, &termio->c_oflag) < 0 || + put_user(termios->c_cflag, &termio->c_cflag) < 0 || + put_user(termios->c_lflag, &termio->c_lflag) < 0 || + put_user(termios->c_line, &termio->c_line) < 0 || + copy_to_user(termio->c_cc, termios->c_cc, NCC) != 0) + return -EFAULT; + + return 0; } +#ifdef TCGETS2 static inline int user_termios_to_kernel_termios(struct ktermios *k, struct termios2 __user *u) { @@ -108,7 +135,20 @@ static inline int kernel_termios_to_user_termios_1(struct termios __user *u, { return copy_to_user(u, k, sizeof(struct termios)); } +#else /* TCGETS2 */ +static inline int user_termios_to_kernel_termios(struct ktermios *k, + struct termios __user *u) +{ + return copy_from_user(k, u, sizeof(struct termios)); +} + +static inline int kernel_termios_to_user_termios(struct termios __user *u, + struct ktermios *k) +{ + return copy_to_user(u, k, sizeof(struct termios)); +} +#endif /* TCGETS2 */ #endif /* __KERNEL__ */ -#endif /* _ASM_X86_TERMIOS_H */ +#endif /* _ASM_GENERIC_TERMIOS_H */ -- 2.20.1