On Wed, Jun 12, 2024 at 05:13:39PM +0800, David Gow wrote:
On Tue, 11 Jun 2024 at 05:33, Kees Cook <kees@xxxxxxxxxx> wrote:
Convert the runtime tests of hardened usercopy to standard KUnit tests.
Co-developed-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
Signed-off-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200721174654.72132-1-vitor@xxxxxxxxxxx
Tested-by: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
---
This looks good, particularly with the x86 fix applied.
It's still hanging on m68k -- I think at the 'illegal reversed
copy_to_user passed' test -- but I'll admit to not having tried to
debug it further.
One other (set of) notes below about using KUNIT_EXPECT_MEMEQ_MSG(),
otherwise (assuming the m68k stuff isn't actually a regression, which
I haven't tested but I imagine is unlikely),
Hi Geert,
I'm trying to debug a hang on m68k in the usercopy behavioral testing
routines. It's testing for the pathological case of having inverted
arguments to copy_to_user():
user_addr = kunit_vm_mmap(test, NULL, 0, priv->size,
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_ANONYMOUS | MAP_PRIVATE, 0);
...
bad_usermem = (char *)user_addr;
...
KUNIT_EXPECT_NE_MSG(test, copy_to_user((char __user *)kmem, bad_usermem,
PAGE_SIZE), 0,
"illegal reversed copy_to_user passed");
On other architectures, this immediate fails because the access_ok()
check rejects it. On m68k with CONFIG_ALTERNATE_USER_ADDRESS_SPACE,
access_ok() short-circuits to "true". I've tried reading
arch/m68k/include/asm/uaccess.h but I'm not sure what's happening under
CONFIG_CPU_HAS_ADDRESS_SPACES.
For now I've excluded that test for m68k, but I'm not sure what's
expected to happen here on m68k for this set of bad arguments. Can you
advise?
Thanks!
-Kees
--
Kees Cook
