From: Dongliang Mu mudongliangabcd@gmail.com
commit cfbe3650dd3ef2ea9a4420ca89d9a4df98af3fb6 upstream.
In nf_tables_commit, if nf_tables_commit_audit_alloc fails, it does not free the adp variable.
Fix this by adding nf_tables_commit_audit_free which frees the linked list with the head node adl.
backtrace: kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] nf_tables_commit_audit_alloc net/netfilter/nf_tables_api.c:8439 [inline] nf_tables_commit+0x16e/0x1760 net/netfilter/nf_tables_api.c:8508 nfnetlink_rcv_batch+0x512/0xa80 net/netfilter/nfnetlink.c:562 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline] nfnetlink_rcv+0x1fa/0x220 net/netfilter/nfnetlink.c:652 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x2c7/0x3e0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x36b/0x6b0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:702 [inline] sock_sendmsg+0x56/0x80 net/socket.c:722
Reported-by: syzbot syzkaller@googlegroups.com Reported-by: kernel test robot lkp@intel.com Fixes: c520292f29b8 ("audit: log nftables configuration change events once per table") Signed-off-by: Dongliang Mu mudongliangabcd@gmail.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/netfilter/nf_tables_api.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
--- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7819,6 +7819,16 @@ static int nf_tables_commit_audit_alloc( return 0; }
+static void nf_tables_commit_audit_free(struct list_head *adl) +{ + struct nft_audit_data *adp, *adn; + + list_for_each_entry_safe(adp, adn, adl, list) { + list_del(&adp->list); + kfree(adp); + } +} + static void nf_tables_commit_audit_collect(struct list_head *adl, struct nft_table *table, u32 op) { @@ -7882,6 +7892,7 @@ static int nf_tables_commit(struct net * ret = nf_tables_commit_audit_alloc(&adl, trans->ctx.table); if (ret) { nf_tables_commit_chain_prepare_cancel(net); + nf_tables_commit_audit_free(&adl); return ret; } if (trans->msg_type == NFT_MSG_NEWRULE || @@ -7891,6 +7902,7 @@ static int nf_tables_commit(struct net * ret = nf_tables_commit_chain_prepare(net, chain); if (ret < 0) { nf_tables_commit_chain_prepare_cancel(net); + nf_tables_commit_audit_free(&adl); return ret; } }