linux/net/ax25
Hannes Frederic Sowa 79462ad02e net: add validation for the socket syscall protocol argument
郭永刚 reported that one could simply crash the kernel as root by
using a simple program:

	int socket_fd;
	struct sockaddr_in addr;
	addr.sin_port = 0;
	addr.sin_addr.s_addr = INADDR_ANY;
	addr.sin_family = 10;

	socket_fd = socket(10,3,0x40000000);
	connect(socket_fd , &addr,16);

AF_INET, AF_INET6 sockets actually only support 8-bit protocol
identifiers. inet_sock's skc_protocol field thus is sized accordingly,
thus larger protocol identifiers simply cut off the higher bits and
store a zero in the protocol fields.

This could lead to e.g. NULL function pointer because as a result of
the cut off inet_num is zero and we call down to inet_autobind, which
is NULL for raw sockets.

kernel: Call Trace:
kernel:  [<ffffffff816db90e>] ? inet_autobind+0x2e/0x70
kernel:  [<ffffffff816db9a4>] inet_dgram_connect+0x54/0x80
kernel:  [<ffffffff81645069>] SYSC_connect+0xd9/0x110
kernel:  [<ffffffff810ac51b>] ? ptrace_notify+0x5b/0x80
kernel:  [<ffffffff810236d8>] ? syscall_trace_enter_phase2+0x108/0x200
kernel:  [<ffffffff81645e0e>] SyS_connect+0xe/0x10
kernel:  [<ffffffff81779515>] tracesys_phase2+0x84/0x89

I found no particular commit which introduced this problem.

CVE: CVE-2015-8543
Cc: Cong Wang <cwang@twopensource.com>
Reported-by: 郭永刚 <guoyonggang@360.cn>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-14 16:09:30 -05:00
..
af_ax25.c net: add validation for the socket syscall protocol argument 2015-12-14 16:09:30 -05:00
ax25_addr.c
ax25_dev.c
ax25_ds_in.c
ax25_ds_subr.c
ax25_ds_timer.c
ax25_iface.c
ax25_in.c ax25: Stop using sock->sk_protinfo. 2015-06-28 16:55:44 -07:00
ax25_ip.c netfilter: Remove spurios included of netfilter.h 2015-06-18 21:14:32 +02:00
ax25_out.c netfilter: Remove spurios included of netfilter.h 2015-06-18 21:14:32 +02:00
ax25_route.c
ax25_std_in.c
ax25_std_subr.c
ax25_std_timer.c
ax25_subr.c NET: AX.25: Stop heartbeat timer on disconnect. 2015-07-15 15:59:58 -07:00
ax25_timer.c
ax25_uid.c netfilter: Remove spurios included of netfilter.h 2015-06-18 21:14:32 +02:00
Kconfig
Makefile
sysctl_net_ax25.c
TODO