lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 19 Oct 2022 11:35:40 +0800 From: David Gow <davidgow@...gle.com> To: Kees Cook <keescook@...omium.org> Cc: linux-hardening@...r.kernel.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH] kunit/fortify: Validate __alloc_size attribute results On Tue, Oct 18, 2022 at 4:27 PM Kees Cook <keescook@...omium.org> wrote: > > Validate the effect of the __alloc_size attribute on allocators. If the > compiler doesn't support __builtin_dynamic_object_size(), skip the test. > > Cc: linux-hardening@...r.kernel.org > Signed-off-by: Kees Cook <keescook@...omium.org> > --- > To pass this depends on the following patches: > https://lore.kernel.org/lkml/20221018073430.never.551-kees@kernel.org/ > https://lore.kernel.org/lkml/20221018082232.never.213-kees@kernel.org/ > To not be skipped, either GCC 12 or Clang is needed. > --- While this _looks_ good, I can't actually get the tests to pass on my machine, with the following all having a __builtin_dynamic_object_size() of -1: - kmalloc_node(size++, gfp, NUMA_NO_NODE) - kzalloc(size++, gfp) - kzalloc_node(size++, gfp, NUMA_NO_NODE) - kcalloc(1, size++, gfp) - kcalloc_node(1, size++, gfp, NUMA_NO_NODE) - kmalloc_array(1, size++, gfp) - kmalloc_array_node(1, size++, gfp, NUMA_NO_NODE) I've been using the following command to run the tests: ./tools/testing/kunit/kunit.py run --kconfig_add CONFIG_FORTIFY_SOURCE=y And I've also tried it on x86_64 and arm64 under qemu, with both gcc 12.2.0 and clang 14.0.6-2, with the same failures. Is there a dependency somewhere I've missed? (I've tried it on the ksefltest/kunit branch, with the mentioned dependencies applied, and also on your for-next/hardening branch, with the missing patches applied.) Cheers, -- David > lib/fortify_kunit.c | 92 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 92 insertions(+) > > diff --git a/lib/fortify_kunit.c b/lib/fortify_kunit.c > index 409af07f340a..5076ba11adfd 100644 > --- a/lib/fortify_kunit.c > +++ b/lib/fortify_kunit.c > @@ -16,7 +16,10 @@ > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > #include <kunit/test.h> > +#include <linux/device.h> > #include <linux/string.h> > +#include <linux/slab.h> > +#include <linux/vmalloc.h> > > static const char array_of_10[] = "this is 10"; > static const char *ptr_of_11 = "this is 11!"; > @@ -60,9 +63,98 @@ static void control_flow_split_test(struct kunit *test) > KUNIT_EXPECT_EQ(test, want_minus_one(pick), SIZE_MAX); > } > > +#define check_alloc(alloc, free) do { \ > + size_t expected = size; \ > + void *p = alloc; \ > + KUNIT_EXPECT_TRUE_MSG(test, p != NULL, #alloc " failed?!\n"); \ > + KUNIT_EXPECT_EQ_MSG(test, __builtin_dynamic_object_size(p, 1), \ > + expected, \ > + "__alloc_size() not working with " #alloc "\n"); \ > + free; \ > +} while (0) > + > +static volatile size_t unknown_size = 50; > + > +static void alloc_size_test(struct kunit *test) > +{ > +#if !__has_builtin(__builtin_dynamic_object_size) > + kunit_skip(test, "Compiler is missing __builtin_dynamic_object_size() support\n"); > +#else > + const char device_name[] = "fortify-test"; > + struct device *dev; > + gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; > + size_t size = unknown_size, prev_size; > + void *orig; > + > + /* kmalloc()-family */ > + check_alloc(kmalloc(size++, gfp), kfree(p)); > + check_alloc(kmalloc_node(size++, gfp, NUMA_NO_NODE), kfree(p)); > + check_alloc(kzalloc(size++, gfp), kfree(p)); > + check_alloc(kzalloc_node(size++, gfp, NUMA_NO_NODE), kfree(p)); > + check_alloc(kcalloc(1, size++, gfp), kfree(p)); > + check_alloc(kcalloc_node(1, size++, gfp, NUMA_NO_NODE), kfree(p)); > + check_alloc(kmalloc_array(1, size++, gfp), kfree(p)); > + check_alloc(kmalloc_array_node(1, size++, gfp, NUMA_NO_NODE), kfree(p)); > + check_alloc(__kmalloc(size++, gfp), kfree(p)); > + check_alloc(__kmalloc_node(size++, gfp, NUMA_NO_NODE), kfree(p)); > + > + /* kmemdup() */ > + prev_size = size; > + size = 11; > + check_alloc(kmemdup("hello there", size, gfp), kfree(p)); > + size = prev_size + 1; > + > + /* krealloc()-family */ > + orig = kmalloc(size++, gfp); > + check_alloc(krealloc(orig, size++, gfp), kfree(p)); > + orig = kmalloc(size++, gfp); > + check_alloc(krealloc_array(orig, 1, size++, gfp), kfree(p)); > + > + /* vmalloc()-family */ > + check_alloc(vmalloc(size++), vfree(p)); > + check_alloc(vzalloc(size++), vfree(p)); > + check_alloc(__vmalloc(size++, gfp), vfree(p)); > + > + /* kvalloc()-family */ > + check_alloc(kvmalloc(size++, gfp), kvfree(p)); > + check_alloc(kvmalloc_node(size++, gfp, NUMA_NO_NODE), kvfree(p)); > + check_alloc(kvzalloc(size++, gfp), kvfree(p)); > + check_alloc(kvzalloc_node(size++, gfp, NUMA_NO_NODE), kvfree(p)); > + check_alloc(kvcalloc(1, size++, gfp), kvfree(p)); > + check_alloc(kvmalloc_array(1, size++, gfp), kvfree(p)); > + > + /* kvrealloc() */ > + prev_size = size++; > + orig = kvmalloc(prev_size, gfp); > + check_alloc(kvrealloc(orig, prev_size, size++, gfp), kfree(p)); > + > + /* Create dummy device for devm_kmalloc()-family tests. */ > + dev = root_device_register(device_name); > + KUNIT_ASSERT_FALSE_MSG(test, IS_ERR(dev), > + "Cannot register test device\n"); > + > + /* devm_kmalloc()-family */ > + check_alloc(devm_kmalloc(dev, size++, gfp), devm_kfree(dev, p)); > + check_alloc(devm_kzalloc(dev, size++, gfp), devm_kfree(dev, p)); > + > + /* devm_kmemdup() */ > + prev_size = size; > + size = 4; > + check_alloc(devm_kmemdup(dev, "Ohai", size, gfp), devm_kfree(dev, p)); > + size = prev_size + 1; > + > + /* devm_kremalloc() */ > + orig = devm_kmalloc(dev, size++, gfp); > + check_alloc(devm_krealloc(dev, orig, size++, gfp), devm_kfree(dev, p)); > + > + device_unregister(dev); > +#endif > +} > + > static struct kunit_case fortify_test_cases[] = { > KUNIT_CASE(known_sizes_test), > KUNIT_CASE(control_flow_split_test), > + KUNIT_CASE(alloc_size_test), > {} > }; > > -- > 2.34.1 >
Powered by blists - more mailing lists