f2fs: add sanity check on ei.len in __update_extent_tree_range()

[PATCH] f2fs: add sanity check on ei.len in __update_extent_tree_range()

Posted by Chao Yu 2 weeks, 2 days ago

Add a sanity check in __update_extent_tree_range() to detect any
zero-sized extent update.

Signed-off-by: wangzijie <wangzijie1@honor.com>
Signed-off-by: Chao Yu <chao@kernel.org>
---
 fs/f2fs/extent_cache.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index 199c1e7a83ef..3070d1cb0676 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -664,6 +664,15 @@ static void __update_extent_tree_range(struct inode *inode,
 	if (!et)
 		return;
 
+	if (unlikely(len == 0)) {
+		f2fs_err_ratelimited(sbi, "%s: extent len is zero, type: %d, "
+			"extent [%u, %u, %u], age [%llu, %llu]",
+			__func__, type, tei->fofs, tei->blk, tei->len,
+			tei->age, tei->last_blocks);
+		f2fs_bug_on(sbi, 1);
+		return;
+	}
+
 	if (type == EX_READ)
 		trace_f2fs_update_read_extent_tree_range(inode, fofs, len,
 						tei->blk, 0);
-- 
2.49.0

Re: [PATCH] f2fs: add sanity check on ei.len in __update_extent_tree_range()

Posted by Jaegeuk Kim 2 weeks ago

Do we need this?

On 09/16, Chao Yu wrote:
> Add a sanity check in __update_extent_tree_range() to detect any
> zero-sized extent update.
> 
> Signed-off-by: wangzijie <wangzijie1@honor.com>
> Signed-off-by: Chao Yu <chao@kernel.org>
> ---
>  fs/f2fs/extent_cache.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
> index 199c1e7a83ef..3070d1cb0676 100644
> --- a/fs/f2fs/extent_cache.c
> +++ b/fs/f2fs/extent_cache.c
> @@ -664,6 +664,15 @@ static void __update_extent_tree_range(struct inode *inode,
>  	if (!et)
>  		return;
>  
> +	if (unlikely(len == 0)) {
> +		f2fs_err_ratelimited(sbi, "%s: extent len is zero, type: %d, "
> +			"extent [%u, %u, %u], age [%llu, %llu]",
> +			__func__, type, tei->fofs, tei->blk, tei->len,
> +			tei->age, tei->last_blocks);
> +		f2fs_bug_on(sbi, 1);
> +		return;
> +	}
> +
>  	if (type == EX_READ)
>  		trace_f2fs_update_read_extent_tree_range(inode, fofs, len,
>  						tei->blk, 0);
> -- 
> 2.49.0

Re: [PATCH] f2fs: add sanity check on ei.len in __update_extent_tree_range()

Posted by Chao Yu 2 weeks ago

On 9/18/25 00:40, Jaegeuk Kim wrote:
> Do we need this?

I think so, it can provide a way to dump more information to troubleshoot
in which function we're trying to update w/ a zero-sized extent.

Thanks,

> 
> On 09/16, Chao Yu wrote:
>> Add a sanity check in __update_extent_tree_range() to detect any
>> zero-sized extent update.
>>
>> Signed-off-by: wangzijie <wangzijie1@honor.com>
>> Signed-off-by: Chao Yu <chao@kernel.org>
>> ---
>>  fs/f2fs/extent_cache.c | 9 +++++++++
>>  1 file changed, 9 insertions(+)
>>
>> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
>> index 199c1e7a83ef..3070d1cb0676 100644
>> --- a/fs/f2fs/extent_cache.c
>> +++ b/fs/f2fs/extent_cache.c
>> @@ -664,6 +664,15 @@ static void __update_extent_tree_range(struct inode *inode,
>>  	if (!et)
>>  		return;
>>  
>> +	if (unlikely(len == 0)) {
>> +		f2fs_err_ratelimited(sbi, "%s: extent len is zero, type: %d, "
>> +			"extent [%u, %u, %u], age [%llu, %llu]",
>> +			__func__, type, tei->fofs, tei->blk, tei->len,
>> +			tei->age, tei->last_blocks);
>> +		f2fs_bug_on(sbi, 1);
>> +		return;
>> +	}
>> +
>>  	if (type == EX_READ)
>>  		trace_f2fs_update_read_extent_tree_range(inode, fofs, len,
>>  						tei->blk, 0);
>> -- 
>> 2.49.0