| Message ID | 20220913173136.1926909-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 06c1c49d0cd1d6cec5b78963109ba728e49e0063 |
| Headers | show |
| Series | fortify: Adjust KUnit test for modular build | expand |
On Tue, Sep 13, 2022 at 10:31:36AM -0700, Kees Cook wrote: > A much better "unknown size" string pointer is available directly from > struct test, so use that instead of a global that isn't shared with > modules. > > Reported-by: Nathan Chancellor <nathan@kernel.org> > Link: https://lore.kernel.org/lkml/YyCOHOchVuE/E7vS@dev-arch.thelio-3990X > Fixes: 875bfd5276f3 ("fortify: Add KUnit test for FORTIFY_SOURCE internals") > Cc: linux-hardening@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > Whoops! Thanks Nathan! :) This fixes it for your reproducer. Confirmed :) Build-tested-by: Nathan Chancellor <nathan@kernel.org> Thanks for the quick fix! > --- > lib/fortify_kunit.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/lib/fortify_kunit.c b/lib/fortify_kunit.c > index 99bc0ea60d27..409af07f340a 100644 > --- a/lib/fortify_kunit.c > +++ b/lib/fortify_kunit.c > @@ -17,7 +17,6 @@ > > #include <kunit/test.h> > #include <linux/string.h> > -#include <linux/init.h> > > static const char array_of_10[] = "this is 10"; > static const char *ptr_of_11 = "this is 11!"; > @@ -31,7 +30,7 @@ static void known_sizes_test(struct kunit *test) > > KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_unknown), SIZE_MAX); > /* Externally defined and dynamically sized string pointer: */ > - KUNIT_EXPECT_EQ(test, __compiletime_strlen(saved_command_line), SIZE_MAX); > + KUNIT_EXPECT_EQ(test, __compiletime_strlen(test->name), SIZE_MAX); > } > > /* This is volatile so the optimizer can't perform DCE below. */ > -- > 2.34.1 >
On Wed, Sep 14, 2022 at 1:31 AM Kees Cook <keescook@chromium.org> wrote: > > A much better "unknown size" string pointer is available directly from > struct test, so use that instead of a global that isn't shared with > modules. > > Reported-by: Nathan Chancellor <nathan@kernel.org> > Link: https://lore.kernel.org/lkml/YyCOHOchVuE/E7vS@dev-arch.thelio-3990X > Fixes: 875bfd5276f3 ("fortify: Add KUnit test for FORTIFY_SOURCE internals") > Cc: linux-hardening@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > Whoops! Thanks Nathan! :) This fixes it for your reproducer. Ah, this is better than saved_command_line, IMO. I don't think it'd necessarily be a _disaster_ to just introduce a new dynamically-sized string here, which would be more explicit, but test->name is at least obviously related to this file anyway. Reviewed-by: David Gow <davidgow@google.com> Cheers -- David > --- > lib/fortify_kunit.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/lib/fortify_kunit.c b/lib/fortify_kunit.c > index 99bc0ea60d27..409af07f340a 100644 > --- a/lib/fortify_kunit.c > +++ b/lib/fortify_kunit.c > @@ -17,7 +17,6 @@ > > #include <kunit/test.h> > #include <linux/string.h> > -#include <linux/init.h> > > static const char array_of_10[] = "this is 10"; > static const char *ptr_of_11 = "this is 11!"; > @@ -31,7 +30,7 @@ static void known_sizes_test(struct kunit *test) > > KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_unknown), SIZE_MAX); > /* Externally defined and dynamically sized string pointer: */ > - KUNIT_EXPECT_EQ(test, __compiletime_strlen(saved_command_line), SIZE_MAX); > + KUNIT_EXPECT_EQ(test, __compiletime_strlen(test->name), SIZE_MAX); > } > > /* This is volatile so the optimizer can't perform DCE below. */ > -- > 2.34.1 >
On Wed, Sep 14, 2022 at 06:13:59PM +0800, David Gow wrote: > On Wed, Sep 14, 2022 at 1:31 AM Kees Cook <keescook@chromium.org> wrote: > > > > A much better "unknown size" string pointer is available directly from > > struct test, so use that instead of a global that isn't shared with > > modules. > > > > Reported-by: Nathan Chancellor <nathan@kernel.org> > > Link: https://lore.kernel.org/lkml/YyCOHOchVuE/E7vS@dev-arch.thelio-3990X > > Fixes: 875bfd5276f3 ("fortify: Add KUnit test for FORTIFY_SOURCE internals") > > Cc: linux-hardening@vger.kernel.org > > Signed-off-by: Kees Cook <keescook@chromium.org> > > --- > > Whoops! Thanks Nathan! :) This fixes it for your reproducer. > > Ah, this is better than saved_command_line, IMO. I don't think it'd > necessarily be a _disaster_ to just introduce a new dynamically-sized > string here, which would be more explicit, but test->name is at least > obviously related to this file anyway. Yeah, and I'm trying to explicitly use a string that the compiler won't immediately be able to see through, so best to get it from an external source. > Reviewed-by: David Gow <davidgow@google.com> Thanks! -Kees
diff --git a/lib/fortify_kunit.c b/lib/fortify_kunit.c index 99bc0ea60d27..409af07f340a 100644 --- a/lib/fortify_kunit.c +++ b/lib/fortify_kunit.c @@ -17,7 +17,6 @@ #include <kunit/test.h> #include <linux/string.h> -#include <linux/init.h> static const char array_of_10[] = "this is 10"; static const char *ptr_of_11 = "this is 11!"; @@ -31,7 +30,7 @@ static void known_sizes_test(struct kunit *test) KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_unknown), SIZE_MAX); /* Externally defined and dynamically sized string pointer: */ - KUNIT_EXPECT_EQ(test, __compiletime_strlen(saved_command_line), SIZE_MAX); + KUNIT_EXPECT_EQ(test, __compiletime_strlen(test->name), SIZE_MAX); } /* This is volatile so the optimizer can't perform DCE below. */
A much better "unknown size" string pointer is available directly from struct test, so use that instead of a global that isn't shared with modules. Reported-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/lkml/YyCOHOchVuE/E7vS@dev-arch.thelio-3990X Fixes: 875bfd5276f3 ("fortify: Add KUnit test for FORTIFY_SOURCE internals") Cc: linux-hardening@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- Whoops! Thanks Nathan! :) This fixes it for your reproducer. --- lib/fortify_kunit.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)