[PATCH v9 03/12] landlock: Refactor landlock_find_rule/insert_rule

[Konstantin Meskhidze (A)]

2/10/2023 8:36 PM, Mickaël Salaün пишет:
> 
> On 16/01/2023 09:58, Konstantin Meskhidze wrote:
>> Add a new landlock_key union and landlock_id structure to support
>> a socket port rule type. A struct landlock_id identifies a unique entry
>> in a ruleset: either a kernel object (e.g inode) or typed data (e.g TCP
>> port). There is one red-black tree per key type.
>> 
>> This patch also adds is_object_pointer() and get_root() helpers.
>> is_object_pointer() returns true if key type is LANDLOCK_KEY_INODE.
>> get_root() helper returns a red_black tree root pointer according to
>> a key type.
>> 
>> Refactor landlock_insert_rule() and landlock_find_rule() to support coming
>> network modifications. Adding or searching a rule in ruleset can now be
>> done thanks to a Landlock ID argument passed to these helpers.
>> 
>> Remove unnecessary inlining.
>> 
> 
> You need to keep the Co-developed-by before the Signed-off-by for my entry.

   Got it.
> 
>> Signed-off-by: Mickaël Salaün <mic at digikod.net>
>> Signed-off-by: Konstantin Meskhidze <konstantin.meskhidze at huawei.com>
>> ---
>> 
>> Changes since v8:
>> * Refactors commit message.
>> * Removes inlining.
>> * Minor fixes.
>> 
>> Changes since v7:
>> * Completes all the new field descriptions landlock_key,
>>    landlock_key_type, landlock_id.
>> * Refactors commit message, adds a co-developer.
>> 
>> Changes since v6:
>> * Adds union landlock_key, enum landlock_key_type, and struct
>>    landlock_id.
>> * Refactors ruleset functions and improves switch/cases: create_rule(),
>>    insert_rule(), get_root(), is_object_pointer(), free_rule(),
>>    landlock_find_rule().
>> * Refactors landlock_append_fs_rule() functions to support new
>>    landlock_id type.
>> 
>> Changes since v5:
>> * Formats code with clang-format-14.
>> 
>> Changes since v4:
>> * Refactors insert_rule() and create_rule() functions by deleting
>> rule_type from their arguments list, it helps to reduce useless code.
>> 
>> Changes since v3:
>> * Splits commit.
>> * Refactors landlock_insert_rule and landlock_find_rule functions.
>> * Rename new_ruleset->root_inode.
>> 
>> ---
>>   security/landlock/fs.c      |  49 ++++++------
>>   security/landlock/ruleset.c | 148 +++++++++++++++++++++++++-----------
>>   security/landlock/ruleset.h |  65 +++++++++++++---
>>   3 files changed, 185 insertions(+), 77 deletions(-)
>> 
>> diff --git a/security/landlock/fs.c b/security/landlock/fs.c
>> index 0ae54a639e16..273ed8549da1 100644
>> --- a/security/landlock/fs.c
>> +++ b/security/landlock/fs.c
> 
> [...]
> 
>> @@ -191,12 +193,15 @@ int landlock_append_fs_rule(struct landlock_ruleset *const ruleset,
>>    *
>>    * Returns NULL if no rule is found or if @dentry is negative.
>>    */
>> -static inline const struct landlock_rule *
>> +static const struct landlock_rule *
> 
> Can you please create a (previous) dedicated patch for all the inlining
> changes?
>  
   a patch with just inlining changes?
> 
>>   find_rule(const struct landlock_ruleset *const domain,
>>   	  const struct dentry *const dentry)
>>   {
>>   	const struct landlock_rule *rule;
>>   	const struct inode *inode;
>> +	struct landlock_id id = {
>> +		.type = LANDLOCK_KEY_INODE,
>> +	};
>>   
>>   	/* Ignores nonexistent leafs. */
>>   	if (d_is_negative(dentry))
> 
> [...]
> 
>> @@ -652,7 +657,7 @@ static inline int check_access_path(const struct landlock_ruleset *const domain,
>>   }
>>   
>>   static int current_check_access_path(const struct path *const path,
>> -					    const access_mask_t access_request)
>> +				     const access_mask_t access_request)
> 
> This syntax fix should be moved to patch 2/12.
> 
   Ok. Got it.
> 
> [...]
> 
>> diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c
>> index 1f3188b4e313..c5c88a100f74 100644
>> --- a/security/landlock/ruleset.c
>> +++ b/security/landlock/ruleset.c
> 
> [...]
> 
>> @@ -285,23 +333,23 @@ static int merge_ruleset(struct landlock_ruleset *const dst,
> 
> 
>> -		if (WARN_ON_ONCE(walker_rule->num_layers != 1)) {
>> -			err = -EINVAL;
>> -			goto out_unlock;
>> -		}
>> -		if (WARN_ON_ONCE(walker_rule->layers[0].level != 0)) {
>> -			err = -EINVAL;
>> -			goto out_unlock;
>> -		}
>> +		if (WARN_ON_ONCE(walker_rule->num_layers != 1))
>> +			return -EINVAL;
>> +		if (WARN_ON_ONCE(walker_rule->layers[0].level != 0))
>> +			return -EINVAL;
> 
> This introduces two potential bugs. Why change this code?

   My bad. These changes will appear in 4/12. Will be fixed.
   Thanks.
> .