Re: [PATCH] init: do_mounts: free the ramfs info of the boot rootfs

[Zenghui Yu]

On 10/27/26 5:48 PM, Breno Leitao wrote:
> On Fri, Oct 16, 2026 at 07:27:58AM -0700, Breno Leitao wrote:
> > Kmemleak is reporting the following leak in ramfs_init_fs_context:
> >
> >   unreferenced object 0xffff000080302480 (size 8):
> >     comm "swapper/0", pid 0, jiffies 4294667306
> >     hex dump (first 8 bytes):
> >       ed 01 00 00 00 00 00 00                          ........
> >     backtrace (crc bea23b04):
> >       __kmalloc_cache_noprof+0x28c/0x5a0
> >       ramfs_init_fs_context+0x5c/0xf8
> >       rootfs_init_fs_context+0x30/0x40
> >       alloc_fs_context+0x4c0/0x6a8
> >       fs_context_for_mount+0x28/0x40
> >       vfs_kern_mount+0x40/0x220
> >       init_mount_tree+0x80/0x440
> >       mnt_init+0x138/0x170
> >       vfs_caches_init+0x2c/0x48
> >       start_kernel+0x350/0x3f8
> >
> > When init pivot_root()s away from a ramfs-backed boot rootfs and
> > unmounts it, the rootfs superblock is killed with kill_anon_super() and
> > the struct ramfs_fs_info allocated by ramfs_init_fs_context() is never
> > freed.
> >
> > Kill a ramfs-backed rootfs with ramfs_kill_sb(). A tmpfs-backed one keeps
> > kill_anon_super(), as shmem frees its info in ->put_super.
> >
> > Fixes: 576ee5dfd459 ("fs: add immutable rootfs")
> > Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
> 
> Ping?

There is a similar fix for that.

https://lore.kernel.org/20261009055546.85279-1-kmehltretter@xxxxxxxxx