[PATCH 04/11] fs: free inodes we no longer need

[Ahmad Fatoum]

Hello Sascha,

On 6/15/20 8:02 AM, Sascha Hauer wrote:
> So far we freed the no longer needed inodes only at unmount time.
> Let's trust our reference counting a bit more and free them once
> the reference counter hits zero.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  fs/fs.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/fs.c b/fs/fs.c
> index cecb3d70e0..e04cadfe5d 100644
> --- a/fs/fs.c
> +++ b/fs/fs.c
> @@ -1090,10 +1090,12 @@ void iput(struct inode *inode)
>  	if (!inode)
>  		return;
>  
> -	if (!inode->i_count)
> -		return;
> -
>  	inode->i_count--;
> +
> +	if (!inode->i_count) {
> +		list_del(&inode->i_sb_list);

There is no explicit initialization of i_sb_list anywhere, only
list_add.

Without reverting this patch, I can reproduce null pointer dereference
booting from squashfs as i_sb_list remained uninitialized when this
line is executed.

Can you drop this patch for now?


> +		destroy_inode(inode);
> +	}
>  }
>  
>  struct inode *iget(struct inode *inode)
> 

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