Re: [PATCH v3] f2fs: fix valid block count leak on data block allocation failure

[Chao Yu <chao@kernel.org>]

On 8/4/26 08:54, Chen Changcheng wrote:
> In __allocate_data_block(), when allocating a new data block
> (dn->data_blkaddr == NULL_ADDR), inc_valid_block_count() is
> called first to increment total_valid_block_count and i_blocks.
> If the subsequent f2fs_allocate_data_block() fails, the function
> returns the error directly without rolling back the
> already-incremented block counts, causing a permanent leak.
> 
> Fix this by calling dec_valid_block_count() to undo the
> increment before returning the error. The condition
> old_blkaddr == NULL_ADDR precisely identifies the case where
> inc_valid_block_count() was called.
> 
> Fixes: 7d009e048d7c ("f2fs: fix to handle segment allocation failure correctly")
> Cc: <stable@vger.kernel.org>
> Reviewed-by: Chao Yu <chao@kernel.org>
> Signed-off-by: Chen Changcheng <chenchangcheng@kylinos.cn>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,