From 446f24d1199e8a546ba7c97da3fbb9a505a94795 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Tue, 30 Apr 2013 15:28:42 -0700 Subject: Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS The help text for this config is duplicated across the x86, parisc, and s390 Kconfig.debug files. Arnd Bergman noted that the help text was slightly misleading and should be fixed to state that enabling this option isn't a problem when using pre 4.4 gcc. To simplify the rewording, consolidate the text into lib/Kconfig.debug and modify it there to be more explicit about when you should say N to this config. Also, make the text a bit more generic by stating that this option enables compile time checks so we can cover architectures which emit warnings vs. ones which emit errors. The details of how an architecture decided to implement the checks isn't as important as the concept of compile time checking of copy_from_user() calls. While we're doing this, remove all the copy_from_user_overflow() code that's duplicated many times and place it into lib/ so that any architecture supporting this option can get the function for free. Signed-off-by: Stephen Boyd Acked-by: Arnd Bergmann Acked-by: Ingo Molnar Acked-by: H. Peter Anvin Cc: Arjan van de Ven Acked-by: Helge Deller Cc: Heiko Carstens Cc: Stephen Rothwell Cc: Chris Metcalf Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/tile/Kconfig | 8 +------- arch/tile/include/asm/uaccess.h | 7 ++++++- arch/tile/lib/uaccess.c | 8 -------- 3 files changed, 7 insertions(+), 16 deletions(-) (limited to 'arch/tile') diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index 25877aebc685..0f712f4e1b33 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -19,6 +19,7 @@ config TILE select HAVE_SYSCALL_WRAPPERS if TILEGX select VIRT_TO_BUS select SYS_HYPERVISOR + select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS select ARCH_HAVE_NMI_SAFE_CMPXCHG select GENERIC_CLOCKEVENTS select MODULES_USE_ELF_RELA @@ -114,13 +115,6 @@ config STRICT_DEVMEM config SMP def_bool y -# Allow checking for compile-time determined overflow errors in -# copy_from_user(). There are still unprovable places in the -# generic code as of 2.6.34, so this option is not really compatible -# with -Werror, which is more useful in general. -config DEBUG_COPY_FROM_USER - def_bool n - config HVC_TILE depends on TTY select HVC_DRIVER diff --git a/arch/tile/include/asm/uaccess.h b/arch/tile/include/asm/uaccess.h index 9ab078a4605d..8a082bc6bca5 100644 --- a/arch/tile/include/asm/uaccess.h +++ b/arch/tile/include/asm/uaccess.h @@ -395,7 +395,12 @@ _copy_from_user(void *to, const void __user *from, unsigned long n) return n; } -#ifdef CONFIG_DEBUG_COPY_FROM_USER +#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS +/* + * There are still unprovable places in the generic code as of 2.6.34, so this + * option is not really compatible with -Werror, which is more useful in + * general. + */ extern void copy_from_user_overflow(void) __compiletime_warning("copy_from_user() size is not provably correct"); diff --git a/arch/tile/lib/uaccess.c b/arch/tile/lib/uaccess.c index f8d398c9ee7f..030abe3ee4f1 100644 --- a/arch/tile/lib/uaccess.c +++ b/arch/tile/lib/uaccess.c @@ -22,11 +22,3 @@ int __range_ok(unsigned long addr, unsigned long size) is_arch_mappable_range(addr, size)); } EXPORT_SYMBOL(__range_ok); - -#ifdef CONFIG_DEBUG_COPY_FROM_USER -void copy_from_user_overflow(void) -{ - WARN(1, "Buffer overflow detected!\n"); -} -EXPORT_SYMBOL(copy_from_user_overflow); -#endif -- cgit v1.2.3