On Mon, Dec 07, 2015 at 06:48:07PM +0800, Xin Long wrote: > when we use 'nft -f' to sumbit rules, it will build multiple rules into > one netlink skb to send to kernel, kernel will process them one by one. > meanwhile, it add the trans into commit_list to record every commit. > if one of them's return value is -EAGAIN, status |= NFNL_BATCH_REPLAY > will be marked. after all the process is done. it will roll back all the > commits. > > now kernel use list_add_tail to add trans to commit, and use > list_for_each_entry_safe to roll back. which means the order of adding > and rollback is the same. that will cause some cases cannot work well, > even trigger call trace, like: > > 1. add a set into table foo [return -EAGAIN]: > commit_list = 'add set trans' > 2. del foo: > commit_list = 'add set trans' -> 'del set trans' -> 'del tab trans' > then nf_tables_abort will be called to roll back: > firstly process 'add set trans': > case NFT_MSG_NEWSET: > trans->ctx.table->use--; > list_del_rcu(&nft_trans_set(trans)->list); > > it will del the set from the table foo, but it has removed when del > table foo [step 2], then the kernel will panic. > > the right order of rollback should be: > 'del tab trans' -> 'del set trans' -> 'add set trans'. > which is opposite with commit_list order. > > so fix it by rolling back commits with reverse order in nf_tables_abort. You're reporting a kernel panic. Could you please provide a sequence of commands to reproduce it with the existing code? Thanks. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
