diff options
| -rw-r--r-- | arch/x86/Kconfig.debug | 9 | ||||
| -rw-r--r-- | arch/x86/configs/i386_defconfig | 2 | ||||
| -rw-r--r-- | arch/x86/configs/x86_64_defconfig | 2 | ||||
| -rw-r--r-- | arch/x86/mm/pat.c | 6 | ||||
| -rw-r--r-- | drivers/char/mem.c | 2 |
5 files changed, 11 insertions, 10 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index f0cf5d99079..51c82147795 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -5,14 +5,15 @@ config TRACE_IRQFLAGS_SUPPORT source "lib/Kconfig.debug" -config PROMISC_DEVMEM - bool "Allow unlimited access to /dev/mem" - default y +config STRICT_DEVMEM + bool "Filter access to /dev/mem" help If this option is left on, you allow userspace (root) access to all of memory, including kernel and userspace memory. Accidental access to this is obviously disastrous, but specific access can - be used by people debugging the kernel. + be used by people debugging the kernel. Note that with PAT support + enabled, even in this case there are restrictions on /dev/mem + use due to the cache aliasing requirements. If this option is switched on, the /dev/mem file only allows userspace access to PCI space and the BIOS code and data regions. diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig index 9bc34e2033e..4d73f53287b 100644 --- a/arch/x86/configs/i386_defconfig +++ b/arch/x86/configs/i386_defconfig @@ -2047,7 +2047,7 @@ CONFIG_PROVIDE_OHCI1394_DMA_INIT=y # CONFIG_SAMPLES is not set # CONFIG_KGDB is not set CONFIG_HAVE_ARCH_KGDB=y -# CONFIG_NONPROMISC_DEVMEM is not set +# CONFIG_STRICT_DEVMEM is not set CONFIG_EARLY_PRINTK=y CONFIG_DEBUG_STACKOVERFLOW=y CONFIG_DEBUG_STACK_USAGE=y diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig index ae5124e064d..a4045242962 100644 --- a/arch/x86/configs/x86_64_defconfig +++ b/arch/x86/configs/x86_64_defconfig @@ -2012,7 +2012,7 @@ CONFIG_PROVIDE_OHCI1394_DMA_INIT=y # CONFIG_SAMPLES is not set # CONFIG_KGDB is not set CONFIG_HAVE_ARCH_KGDB=y -# CONFIG_NONPROMISC_DEVMEM is not set +# CONFIG_STRICT_DEVMEM is not set CONFIG_EARLY_PRINTK=y CONFIG_DEBUG_STACKOVERFLOW=y CONFIG_DEBUG_STACK_USAGE=y diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index c34dc483839..6bb597f4d70 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -373,8 +373,8 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, return vma_prot; } -#ifndef CONFIG_PROMISC_DEVMEM -/* This check is done in drivers/char/mem.c in case of !PROMISC_DEVMEM*/ +#ifdef CONFIG_STRICT_DEVMEM +/* This check is done in drivers/char/mem.c in case of STRICT_DEVMEM*/ static inline int range_is_allowed(unsigned long pfn, unsigned long size) { return 1; @@ -398,7 +398,7 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size) } return 1; } -#endif /* CONFIG_PROMISC_DEVMEM */ +#endif /* CONFIG_STRICT_DEVMEM */ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, unsigned long size, pgprot_t *vma_prot) diff --git a/drivers/char/mem.c b/drivers/char/mem.c index de05775bd68..b6772d65754 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -80,7 +80,7 @@ static inline int valid_mmap_phys_addr_range(unsigned long pfn, size_t size) } #endif -#ifndef CONFIG_PROMISC_DEVMEM +#ifdef CONFIG_STRICT_DEVMEM static inline int range_is_allowed(unsigned long pfn, unsigned long size) { u64 from = ((u64)pfn) << PAGE_SHIFT; |