Re: [PATCH v2] ovl: keep err zero after successful ovl_cache_get()

[Christian Brauner]

On Thu, 14 May 2026 07:42:57 -0700, Nirmoy Das wrote:
> ovl_iterate_merged() stores PTR_ERR(cache) in err before checking
> IS_ERR(cache). On success err holds the truncated cache pointer and
> can be returned as a bogus non-zero error.
> 
> The syzbot reproducer reaches this through overlay-on-overlay readdir:
> 
>   getdents64
>     iterate_dir(outer overlay file)
>       ovl_iterate_merged()
>         ovl_cache_get()
>           ovl_dir_read_merged()
>             ovl_dir_read()
>               iterate_dir(inner overlay file)
>                 ovl_iterate_merged()
> 
> [...]

Applied to the vfs.fixes branch of the vfs/vfs.git tree.
Patches in the vfs.fixes branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.fixes

[1/1] ovl: keep err zero after successful ovl_cache_get()
      https://git.kernel.org/vfs/vfs/c/1711b6ed6953