From 0217ed2848e8538bcf9172d97ed2eeb4a26041bb Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 15 Mar 2021 03:06:58 -0700 Subject: tipc: better validate user input in tipc_nl_retrieve_key() Before calling tipc_aead_key_size(ptr), we need to ensure we have enough data to dereference ptr->keylen. We probably also want to make sure tipc_aead_key_size() wont overflow with malicious ptr->keylen values. Syzbot reported: BUG: KMSAN: uninit-value in __tipc_nl_node_set_key net/tipc/node.c:2971 [inline] BUG: KMSAN: uninit-value in tipc_nl_node_set_key+0x9bf/0x13b0 net/tipc/node.c:3023 CPU: 0 PID: 21060 Comm: syz-executor.5 Not tainted 5.11.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:120 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197 __tipc_nl_node_set_key net/tipc/node.c:2971 [inline] tipc_nl_node_set_key+0x9bf/0x13b0 net/tipc/node.c:3023 genl_family_rcv_msg_doit net/netlink/genetlink.c:739 [inline] genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] genl_rcv_msg+0x1319/0x1610 net/netlink/genetlink.c:800 netlink_rcv_skb+0x6fa/0x810 net/netlink/af_netlink.c:2494 genl_rcv+0x63/0x80 net/netlink/genetlink.c:811 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x11d6/0x14a0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x1740/0x1840 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2345 ___sys_sendmsg net/socket.c:2399 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2432 __compat_sys_sendmsg net/compat.c:347 [inline] __do_compat_sys_sendmsg net/compat.c:354 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:351 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:351 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f60549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f555a5fc EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000200 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline] kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:104 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:76 slab_alloc_node mm/slub.c:2907 [inline] __kmalloc_node_track_caller+0xa37/0x1430 mm/slub.c:4527 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x2f8/0xb30 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1099 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1176 [inline] netlink_sendmsg+0xdbc/0x1840 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2345 ___sys_sendmsg net/socket.c:2399 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2432 __compat_sys_sendmsg net/compat.c:347 [inline] __do_compat_sys_sendmsg net/compat.c:354 [inline] __se_compat_sys_sendmsg+0xa7/0xc0 net/compat.c:351 __ia32_compat_sys_sendmsg+0x4a/0x70 net/compat.c:351 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Fixes: e1f32190cf7d ("tipc: add support for AEAD key setting via netlink") Signed-off-by: Eric Dumazet Cc: Tuong Lien Cc: Jon Maloy Cc: Ying Xue Reported-by: syzbot Signed-off-by: David S. Miller --- net/tipc/node.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'net/tipc') diff --git a/net/tipc/node.c b/net/tipc/node.c index 008670d1f43e..136338b85504 100644 --- a/net/tipc/node.c +++ b/net/tipc/node.c @@ -2895,17 +2895,22 @@ int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb, #ifdef CONFIG_TIPC_CRYPTO static int tipc_nl_retrieve_key(struct nlattr **attrs, - struct tipc_aead_key **key) + struct tipc_aead_key **pkey) { struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY]; + struct tipc_aead_key *key; if (!attr) return -ENODATA; - *key = (struct tipc_aead_key *)nla_data(attr); - if (nla_len(attr) < tipc_aead_key_size(*key)) + if (nla_len(attr) < sizeof(*key)) + return -EINVAL; + key = (struct tipc_aead_key *)nla_data(attr); + if (key->keylen > TIPC_AEAD_KEYLEN_MAX || + nla_len(attr) < tipc_aead_key_size(key)) return -EINVAL; + *pkey = key; return 0; } -- cgit v1.2.3