Re: [PATCH] fs: romfs: Fix potential uninitialized memory leak

From: Christian Brauner
Date: Sat Jan 20 2024 - 02:29:09 EST


On Fri, Jan 19, 2024 at 03:21:04PM +0100, Christian Brauner wrote:
> On Thu, 18 Jan 2024 15:14:12 +0800, Fullway Wang wrote:
> > romfs_dev_read() fetches a caller-supplied number of bytes from the
> > backing device in an all-or-nothing manner.
> >
> > Commit bcf85fc fixed CVE-2020-29371, which exposed the bug when
> > the requested length crossed the filesystem size limit, the number
> > of bytes to requested was truncated. However, in romfs_readdir()
> > in super.c, the requested number is firstly truncated with
> > romfs_dev_strnlen() then passed to romfs_dev_read(), leaving
> > the bug exploitable still.
> >
> > [...]
>
> Applied to the vfs.misc branch of the vfs/vfs.git tree.
> Patches in the vfs.misc 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.misc
>
> [1/1] fs: romfs: Fix potential uninitialized memory leak
> https://git.kernel.org/vfs/vfs/c/530041d36e37

This fails to even compile. Dropped.