From: Hangyu Hua hbh25y@gmail.com
stable inclusion from stable-v6.6.8 commit ce5a6df21a00a02c155f2cf269f0e258aa522346 bugzilla: https://gitee.com/openeuler/kernel/issues/I99K53
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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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: 1dd539577c42 ("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 Signed-off-by: ZhangPeng zhangpeng362@huawei.com --- fs/fuse/dax.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c index 23904a6a9a96..12ef91d170bb 100644 --- a/fs/fuse/dax.c +++ b/fs/fuse/dax.c @@ -1222,6 +1222,7 @@ 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; } }