diff mbox series

[RESEND,5/8] maple_tree: make mas_validate_limits() check root node and node limit

Message ID 20230707101057.29326-6-zhangpeng.00@bytedance.com (mailing list archive)
State New
Headers show
Series Improve the validation for maple tree and some cleanup | expand

Commit Message

Peng Zhang July 7, 2023, 10:10 a.m. UTC
Update mas_validate_limits() to check root node, check node limit pivot
if there is enough room for it to exist and check data_end. Remove the
check for child existence as it is done in mas_validate_child_slot().

Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
---
 lib/maple_tree.c | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

Comments

Liam R. Howlett July 7, 2023, 2:58 p.m. UTC | #1
* Peng Zhang <zhangpeng.00@bytedance.com> [230707 06:11]:
> Update mas_validate_limits() to check root node, check node limit pivot
> if there is enough room for it to exist and check data_end. Remove the
> check for child existence as it is done in mas_validate_child_slot().
> 

The comments for this function say:
 * Validate all pivots are within mas->min and mas->max.

This needs adjusting since we are doing a whole lot more now..

Validate limits is now checking metadata ends where the maximum ends,
checks the pivots are within the limits of the node, and ensures
there is no slots or pivots set outside of the end of the data.

Did I miss anything?

> Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
> ---
>  lib/maple_tree.c | 26 +++++++++++---------------
>  1 file changed, 11 insertions(+), 15 deletions(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 88d6373f37b0..e84a042b6d84 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -7148,26 +7148,15 @@ static void mas_validate_limits(struct ma_state *mas)
>  	void __rcu **slots = ma_slots(mte_to_node(mas->node), type);
>  	unsigned long *pivots = ma_pivots(mas_mn(mas), type);
>  
> -	/* all limits are fine here. */
> -	if (mte_is_root(mas->node))
> -		return;
> -
>  	for (i = 0; i < mt_slots[type]; i++) {
>  		unsigned long piv;
>  
>  		piv = mas_safe_pivot(mas, pivots, i, type);
>  
> -		if (!piv && (i != 0))
> -			break;
> -
> -		if (!mte_is_leaf(mas->node)) {
> -			void *entry = mas_slot(mas, slots, i);
> -
> -			if (!entry)
> -				pr_err("%p[%u] cannot be null\n",
> -				       mas_mn(mas), i);
> -
> -			MT_BUG_ON(mas->tree, !entry);
> +		if (!piv && (i != 0)) {
> +			pr_err("Missing node limit pivot at %p[%u]",
> +			       mas_mn(mas), i);
> +			MAS_WARN_ON(mas, 1);
>  		}
>  
>  		if (prev_piv > piv) {
> @@ -7190,6 +7179,13 @@ static void mas_validate_limits(struct ma_state *mas)
>  		if (piv == mas->max)
>  			break;
>  	}
> +
> +	if (mas_data_end(mas) != i) {
> +		pr_err("node%p: data_end %u != the last slot offset %u\n",
> +		       mas_mn(mas), mas_data_end(mas), i);
> +		MT_BUG_ON(mas->tree, 1);
> +	}
> +
>  	for (i += 1; i < mt_slots[type]; i++) {
>  		void *entry = mas_slot(mas, slots, i);
>  
> -- 
> 2.20.1
> 
> 
> -- 
> maple-tree mailing list
> maple-tree@lists.infradead.org
> https://lists.infradead.org/mailman/listinfo/maple-tree
Peng Zhang July 10, 2023, 9:11 a.m. UTC | #2
在 2023/7/7 22:58, Liam R. Howlett 写道:
> * Peng Zhang <zhangpeng.00@bytedance.com> [230707 06:11]:
>> Update mas_validate_limits() to check root node, check node limit pivot
>> if there is enough room for it to exist and check data_end. Remove the
>> check for child existence as it is done in mas_validate_child_slot().
>>
> 
> The comments for this function say:
>   * Validate all pivots are within mas->min and mas->max.
> 
> This needs adjusting since we are doing a whole lot more now..
Thanks, I will update it in v2.
> 
> Validate limits is now checking metadata ends where the maximum ends,
> checks the pivots are within the limits of the node, and ensures
> there is no slots or pivots set outside of the end of the data.
> 
> Did I miss anything?
You're right, that's exactly all the checks it does.
> 
>> Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
>> ---
>>   lib/maple_tree.c | 26 +++++++++++---------------
>>   1 file changed, 11 insertions(+), 15 deletions(-)
>>
>> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
>> index 88d6373f37b0..e84a042b6d84 100644
>> --- a/lib/maple_tree.c
>> +++ b/lib/maple_tree.c
>> @@ -7148,26 +7148,15 @@ static void mas_validate_limits(struct ma_state *mas)
>>   	void __rcu **slots = ma_slots(mte_to_node(mas->node), type);
>>   	unsigned long *pivots = ma_pivots(mas_mn(mas), type);
>>   
>> -	/* all limits are fine here. */
>> -	if (mte_is_root(mas->node))
>> -		return;
>> -
>>   	for (i = 0; i < mt_slots[type]; i++) {
>>   		unsigned long piv;
>>   
>>   		piv = mas_safe_pivot(mas, pivots, i, type);
>>   
>> -		if (!piv && (i != 0))
>> -			break;
>> -
>> -		if (!mte_is_leaf(mas->node)) {
>> -			void *entry = mas_slot(mas, slots, i);
>> -
>> -			if (!entry)
>> -				pr_err("%p[%u] cannot be null\n",
>> -				       mas_mn(mas), i);
>> -
>> -			MT_BUG_ON(mas->tree, !entry);
>> +		if (!piv && (i != 0)) {
>> +			pr_err("Missing node limit pivot at %p[%u]",
>> +			       mas_mn(mas), i);
>> +			MAS_WARN_ON(mas, 1);
>>   		}
>>   
>>   		if (prev_piv > piv) {
>> @@ -7190,6 +7179,13 @@ static void mas_validate_limits(struct ma_state *mas)
>>   		if (piv == mas->max)
>>   			break;
>>   	}
>> +
>> +	if (mas_data_end(mas) != i) {
>> +		pr_err("node%p: data_end %u != the last slot offset %u\n",
>> +		       mas_mn(mas), mas_data_end(mas), i);
>> +		MT_BUG_ON(mas->tree, 1);
>> +	}
>> +
>>   	for (i += 1; i < mt_slots[type]; i++) {
>>   		void *entry = mas_slot(mas, slots, i);
>>   
>> -- 
>> 2.20.1
>>
>>
>> -- 
>> maple-tree mailing list
>> maple-tree@lists.infradead.org
>> https://lists.infradead.org/mailman/listinfo/maple-tree
diff mbox series

Patch

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 88d6373f37b0..e84a042b6d84 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -7148,26 +7148,15 @@  static void mas_validate_limits(struct ma_state *mas)
 	void __rcu **slots = ma_slots(mte_to_node(mas->node), type);
 	unsigned long *pivots = ma_pivots(mas_mn(mas), type);
 
-	/* all limits are fine here. */
-	if (mte_is_root(mas->node))
-		return;
-
 	for (i = 0; i < mt_slots[type]; i++) {
 		unsigned long piv;
 
 		piv = mas_safe_pivot(mas, pivots, i, type);
 
-		if (!piv && (i != 0))
-			break;
-
-		if (!mte_is_leaf(mas->node)) {
-			void *entry = mas_slot(mas, slots, i);
-
-			if (!entry)
-				pr_err("%p[%u] cannot be null\n",
-				       mas_mn(mas), i);
-
-			MT_BUG_ON(mas->tree, !entry);
+		if (!piv && (i != 0)) {
+			pr_err("Missing node limit pivot at %p[%u]",
+			       mas_mn(mas), i);
+			MAS_WARN_ON(mas, 1);
 		}
 
 		if (prev_piv > piv) {
@@ -7190,6 +7179,13 @@  static void mas_validate_limits(struct ma_state *mas)
 		if (piv == mas->max)
 			break;
 	}
+
+	if (mas_data_end(mas) != i) {
+		pr_err("node%p: data_end %u != the last slot offset %u\n",
+		       mas_mn(mas), mas_data_end(mas), i);
+		MT_BUG_ON(mas->tree, 1);
+	}
+
 	for (i += 1; i < mt_slots[type]; i++) {
 		void *entry = mas_slot(mas, slots, i);