fuse: dax: set fc->dax to NULL in fuse_dax_conn_free()

commit 7f8ed28d1401320bcb02dda81b3c23ab2dc5a6d8 upstream.

fuse_dax_conn_free() will be called when fuse_fill_super_common() fails
after fuse_dax_conn_alloc(). Then deactivate_locked_super() in
virtio_fs_get_tree() will call virtio_kill_sb() to release the discarded
superblock. This will call fuse_dax_conn_free() again in fuse_conn_put(),
resulting in a possible double free.

Fixes: 1dd539577c ("virtiofs: add a mount option to enable dax")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Cc: <stable@vger.kernel.org> # v5.10
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hangyu Hua 2023-11-16 15:57:26 +08:00 committed by Greg Kroah-Hartman
parent 36e2497ac7
commit 0dc6a06c48
1 changed files with 1 additions and 0 deletions

View File

@ -1224,6 +1224,7 @@ void fuse_dax_conn_free(struct fuse_conn *fc)
if (fc->dax) {
fuse_free_dax_mem_ranges(&fc->dax->free_ranges);
kfree(fc->dax);
fc->dax = NULL;
}
}