netdev - Re: [PATCH v7 01/18] landlock: rename access mask

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Message-ID: <45dc56c9-f02d-8501-4175-42ff62e9f310@digikod.net>
Date:   Mon, 12 Sep 2022 19:16:58 +0200
From:   Mickaël Salaün <mic@...ikod.net>
To:     "Konstantin Meskhidze (A)" <konstantin.meskhidze@...wei.com>
Cc:     willemdebruijn.kernel@...il.com, gnoack3000@...il.com,
        linux-security-module@...r.kernel.org, netdev@...r.kernel.org,
        netfilter-devel@...r.kernel.org, anton.sirazetdinov@...wei.com
Subject: Re: [PATCH v7 01/18] landlock: rename access mask


On 09/09/2022 12:42, Konstantin Meskhidze (A) wrote:
> 
> 
> 9/6/2022 11:06 AM, Mickaël Salaün пишет:
>> You can improve the subject with "landlock: Make ruleset's access masks
>> more generic".
>> Please capitalize all subjects this way.
>>
>> On 29/08/2022 19:03, Konstantin Meskhidze wrote:
>>> To support network type rules, this modification renames ruleset's
>>> access masks and modifies it's type to access_masks_t. This patch
>>> adds filesystem helper functions to add and get filesystem mask.
>>>
>>> Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze@...wei.com>
>>> ---
>>>
>>> Changes since v6:
>>> * Adds a new access_masks_t for struct ruleset.
>>> * Renames landlock_set_fs_access_mask() to landlock_add_fs_access_mask()
>>>     because it OR values.
>>> * Makes landlock_add_fs_access_mask() more resilient incorrect values.
>>> * Refactors landlock_get_fs_access_mask().
>>>
>>> Changes since v5:
>>> * Changes access_mask_t to u32.
>>> * Formats code with clang-format-14.
>>>
>>> Changes since v4:
>>> * Deletes struct landlock_access_mask.
>>>
>>> Changes since v3:
>>> * Splits commit.
>>> * Adds get_mask, set_mask helpers for filesystem.
>>> * Adds new struct landlock_access_mask.
>>>
>>> ---
>>>    security/landlock/fs.c       |  7 ++++---
>>>    security/landlock/limits.h   |  1 +
>>>    security/landlock/ruleset.c  | 17 +++++++++--------
>>>    security/landlock/ruleset.h  | 37 ++++++++++++++++++++++++++++++++----
>>>    security/landlock/syscalls.c |  7 ++++---
>>>    5 files changed, 51 insertions(+), 18 deletions(-)
>>
>> [...]
>>
>>> @@ -177,4 +182,28 @@ static inline void landlock_get_ruleset(struct landlock_ruleset *const ruleset)
>>>    		refcount_inc(&ruleset->usage);
>>>    }
>>>
>>> +/* A helper function to set a filesystem mask. */
>>> +static inline void
>>> +landlock_add_fs_access_mask(struct landlock_ruleset *const ruleset,
>>> +			    const access_mask_t fs_access_mask,
>>> +			    const u16 layer_level)
>>> +{
>>> +	access_mask_t fs_mask = fs_access_mask & LANDLOCK_MASK_ACCESS_FS;
>>> +
>>> +	/* Should already be checked in sys_landlock_create_ruleset(). */
>>> +	WARN_ON_ONCE(fs_access_mask != fs_mask);
>>> +	// TODO: Add tests to check "|=" and not "="
>>
>> Please add tests as I explained in a previous email.
> 
>     Do you mean to add this test into TEST_F_FORK(layout1, inval) in
> fs_test.c ???

This is unrelated to the layout1.inval tests. You can create a new 
TEST_F_FORK(layout1, with_net) that also handles TCP_BIND/CONNECT and 
checks a simple subset of TEST_F_FORK(layout1, effective_access) (e.g. 
only read access to dir_s1d2, but not to dir_s2d2). To test the 
complement, you can create a TEST_F_FORK(socket, with_fs) to check that 
bind() works as expected.