[PATCH 4/4] fs: free unused dentries

[Sascha Hauer]

On Tue, Sep 15, 2020 at 07:25:15AM +0200, Ahmad Fatoum wrote:
> Hello Sascha,
> 
> On 9/14/20 3:06 PM, Sascha Hauer wrote:
> > So far we only ever freed dentries when the filesystem they are on is
> > unmounted. With this patch we actually trust reference counting and free
> > the dentries once the reference count hits zero.
> 
> Unless I revert this patch, I run into a crash doing:
> 
> dd if=/dev/zero of=barebox.env count=1
> ./barebox --image=barebox.env
> barebox at barebox sandbox:/ saveenv
> saving environment

"saveenv" answers with: "saveenv: No such file or directory". Did you
mean to do a "saveenv /dev/fd0"?

> barebox at barebox sandbox:/ reset
> =================================================================
> ==894761==ERROR: AddressSanitizer: heap-use-after-free on address 0x60e000005d70 at pc 0x5617cfde210a bp 0x7ffff89957d0 sp 0x7ffff89957c8

I can't reproduce this here unfortunately.

Sascha


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