From: Florian Fainelli <f.fainelli@xxxxxxxxx> Subject: lib: add test module for CONFIG_DEBUG_VIRTUAL Add a test module that allows testing that CONFIG_DEBUG_VIRTUAL works correctly, at least that it can catch invalid calls to virt_to_phys() against the non-linear kernel virtual address map. Link: http://lkml.kernel.org/r/20170808164035.26725-1-f.fainelli@xxxxxxxxx Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Cc: "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/Kconfig.debug | 11 ++++++++ lib/Makefile | 1 lib/test_debug_virtual.c | 49 +++++++++++++++++++++++++++++++++++++ 3 files changed, 61 insertions(+) diff -puN lib/Kconfig.debug~lib-add-test-module-for-config_debug_virtual lib/Kconfig.debug --- a/lib/Kconfig.debug~lib-add-test-module-for-config_debug_virtual +++ a/lib/Kconfig.debug @@ -1930,6 +1930,17 @@ config TEST_KMOD If unsure, say N. +config TEST_DEBUG_VIRTUAL + tristate "Test CONFIG_DEBUG_VIRTUAL feature" + depends on DEBUG_VIRTUAL + help + Test the kernel's ability to detect incorrect calls to + virt_to_phys() done against the non-linear part of the + kernel's virtual address map. + + If unsure, say N. + + source "samples/Kconfig" source "lib/Kconfig.kgdb" diff -puN lib/Makefile~lib-add-test-module-for-config_debug_virtual lib/Makefile --- a/lib/Makefile~lib-add-test-module-for-config_debug_virtual +++ a/lib/Makefile @@ -62,6 +62,7 @@ obj-$(CONFIG_TEST_BITMAP) += test_bitmap obj-$(CONFIG_TEST_UUID) += test_uuid.o obj-$(CONFIG_TEST_PARMAN) += test_parman.o obj-$(CONFIG_TEST_KMOD) += test_kmod.o +obj-$(CONFIG_TEST_DEBUG_VIRTUAL) += test_debug_virtual.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff -puN /dev/null lib/test_debug_virtual.c --- /dev/null +++ a/lib/test_debug_virtual.c @@ -0,0 +1,49 @@ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/sizes.h> + +#include <asm/page.h> +#ifdef CONFIG_MIPS +#include <asm/bootinfo.h> +#endif + +struct foo { + unsigned int bar; +}; + +struct foo *foo; + +static int __init test_debug_virtual_init(void) +{ + phys_addr_t pa; + void *va; + + va = (void *)VMALLOC_START; + pa = virt_to_phys(va); + + pr_info("PA: %pa for VA: 0x%lx\n", &pa, (unsigned long)va); + + foo = kzalloc(sizeof(*foo), GFP_KERNEL); + if (!foo) + return -ENOMEM; + + pa = virt_to_phys(foo); + va = foo; + pr_info("PA: %pa for VA: 0x%lx\n", &pa, (unsigned long)va); + + return 0; +} +module_init(test_debug_virtual_init); + +static void __exit test_debug_virtual_exit(void) +{ + kfree(foo); +} +module_exit(test_debug_virtual_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Test module for CONFIG_DEBUG_VIRTUAL"); _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
