3.2.75-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Hannes Frederic Sowa <[email protected]> [ Upstream commit 79462ad02e861803b3840cc782248c7359451cd9 ] 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 <[email protected]> Reported-by: 郭永刚 <[email protected]> Signed-off-by: Hannes Frederic Sowa <[email protected]> Signed-off-by: David S. Miller <[email protected]> [bwh: Backported to 3.2: open-code U8_MAX] Signed-off-by: Ben Hutchings <[email protected]> --- include/net/sock.h | 1 + net/ax25/af_ax25.c | 3 +++ net/decnet/af_decnet.c | 3 +++ net/ipv4/af_inet.c | 3 +++ net/ipv6/af_inet6.c | 3 +++ net/irda/af_irda.c | 3 +++ 6 files changed, 16 insertions(+) --- a/include/net/sock.h +++ b/include/net/sock.h @@ -302,6 +302,7 @@ struct sock { sk_no_check : 2, sk_userlocks : 4, sk_protocol : 8, +#define SK_PROTOCOL_MAX ((u8)~0U) sk_type : 16; kmemcheck_bitfield_end(flags); int sk_wmem_queued; --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -806,6 +806,9 @@ static int ax25_create(struct net *net, struct sock *sk; ax25_cb *ax25; + if (protocol < 0 || protocol > SK_PROTOCOL_MAX) + return -EINVAL; + if (!net_eq(net, &init_net)) return -EAFNOSUPPORT; --- a/net/decnet/af_decnet.c +++ b/net/decnet/af_decnet.c @@ -681,6 +681,9 @@ static int dn_create(struct net *net, st { struct sock *sk; + if (protocol < 0 || protocol > SK_PROTOCOL_MAX) + return -EINVAL; + if (!net_eq(net, &init_net)) return -EAFNOSUPPORT; --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -279,6 +279,9 @@ static int inet_create(struct net *net, int try_loading_module = 0; int err; + if (protocol < 0 || protocol >= IPPROTO_MAX) + return -EINVAL; + if (unlikely(!inet_ehash_secret)) if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) build_ehash_secret(); --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -109,6 +109,9 @@ static int inet6_create(struct net *net, int try_loading_module = 0; int err; + if (protocol < 0 || protocol >= IPPROTO_MAX) + return -EINVAL; + if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM && !inet_ehash_secret) --- a/net/irda/af_irda.c +++ b/net/irda/af_irda.c @@ -1106,6 +1106,9 @@ static int irda_create(struct net *net, IRDA_DEBUG(2, "%s()\n", __func__); + if (protocol < 0 || protocol > SK_PROTOCOL_MAX) + return -EINVAL; + if (net != &init_net) return -EAFNOSUPPORT; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
