jffs2: check that raw node were preallocated before writing summary
In the Linux kernel, the following vulnerability has been resolved: jffs2: check that raw node were preallocated before writing summary Syzkaller detected a kernel bug in jffs2_link_node_ref, caused by fault injection in jffs2_prealloc_raw_node_refs. jffs2_sum_write_sumnode doesn't check return value of jffs2_prealloc_raw_node_refs and simply lets any error propagate into jffs2_sum_write_data, which eventually calls jffs2_link_node_ref in order to link the summary to an expectedly allocated node. kernel BUG at fs/jffs2/nodelist.c:592! invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 1 PID: 31277 Comm: syz-executor.7 Not tainted 6.1.1