syzbot reports: ===================================================== BUG: KMSAN: uninit-value in nla_validate_range_unsigned lib/nlattr.c:222 [inline] BUG: KMSAN: uninit-value in nla_validate_int_range lib/nlattr.c:336 [inline] BUG: KMSAN: uninit-value in validate_nla lib/nlattr.c:575 [inline] BUG: KMSAN: uninit-value in __nla_validate_parse+0x2e20/0x45c0 lib/nlattr.c:631 nla_validate_range_unsigned lib/nlattr.c:222 [inline] nla_validate_int_range lib/nlattr.c:336 [inline] validate_nla lib/nlattr.c:575 [inline] __nla_validate_parse+0x2e20/0x45c0 lib/nlattr.c:631 __nla_parse+0x5f/0x70 lib/nlattr.c:728 nla_parse_deprecated include/net/netlink.h:703 [inline] nfnetlink_rcv_msg+0x723/0xde0 net/netfilter/nfnetlink.c:275 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2543 nfnetlink_rcv+0x372/0x4950 net/netfilter/nfnetlink.c:659 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0xf49/0x1250 net/netlink/af_netlink.c:1367 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638 __sys_sendmsg net/socket.c:2667 [inline] __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was created at: slab_post_alloc_hook mm/slub.c:3819 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_node+0x5cb/0xbc0 mm/slub.c:3903 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560 __alloc_skb+0x352/0x790 net/core/skbuff.c:651 alloc_skb include/linux/skbuff.h:1296 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1213 [inline] netlink_sendmsg+0xb34/0x13d0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638 __sys_sendmsg net/socket.c:2667 [inline] __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b NLA_BE16 and NLA_BE32 minimum attribute length is not validated, update nla_attr_len and nla_attr_minlen accordingly. After this update, kernel displays: netlink: 'x': attribute type 2 has an invalid length. in case that the attribute payload is too small and it reports -ERANGE to userspace. Fixes: ecaf75ffd5f5 ("netlink: introduce bigendian integer types") Reported-by: syzbot+3f497b07aa3baf2fb4d0@xxxxxxxxxxxxxxxxxxxxxxxxx Reported-by: xingwei lee <xrivendell7@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- lib/nlattr.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/lib/nlattr.c b/lib/nlattr.c index ed2ab43e1b22..be9c576b6e2d 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -30,6 +30,8 @@ static const u8 nla_attr_len[NLA_TYPE_MAX+1] = { [NLA_S16] = sizeof(s16), [NLA_S32] = sizeof(s32), [NLA_S64] = sizeof(s64), + [NLA_BE16] = sizeof(__be16), + [NLA_BE32] = sizeof(__be32), }; static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = { @@ -43,6 +45,8 @@ static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = { [NLA_S16] = sizeof(s16), [NLA_S32] = sizeof(s32), [NLA_S64] = sizeof(s64), + [NLA_BE16] = sizeof(__be16), + [NLA_BE32] = sizeof(__be32), }; /* -- 2.30.2