diff options
| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2015-12-14 22:03:39 +0100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2015-12-30 02:26:03 +0000 |
| commit | ef6d51d24d878be2291d7af783441356eb77649d (patch) | |
| tree | 5954130bfa872b0ceaa7d763fbbe14a421c8dd92 | |
| parent | 5c85649e8da22945f8e4616717543991a81bfba2 (diff) | |
net: add validation for the socket syscall protocol argument
[ 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 <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>
[bwh: Backported to 3.2: open-code U8_MAX]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | include/net/sock.h | 1 | ||||
| -rw-r--r-- | net/ax25/af_ax25.c | 3 | ||||
| -rw-r--r-- | net/decnet/af_decnet.c | 3 | ||||
| -rw-r--r-- | net/ipv4/af_inet.c | 3 | ||||
| -rw-r--r-- | net/ipv6/af_inet6.c | 3 | ||||
| -rw-r--r-- | net/irda/af_irda.c | 3 |
6 files changed, 16 insertions, 0 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 8f7cb22553fe..ce6f641e40d9 100644 --- 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; diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 7b8db0ede163..a314cfd6a642 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -806,6 +806,9 @@ static int ax25_create(struct net *net, struct socket *sock, int protocol, struct sock *sk; ax25_cb *ax25; + if (protocol < 0 || protocol > SK_PROTOCOL_MAX) + return -EINVAL; + if (!net_eq(net, &init_net)) return -EAFNOSUPPORT; diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c index 16fbf8c28e31..c0486c8877c9 100644 --- a/net/decnet/af_decnet.c +++ b/net/decnet/af_decnet.c @@ -681,6 +681,9 @@ static int dn_create(struct net *net, struct socket *sock, int protocol, { struct sock *sk; + if (protocol < 0 || protocol > SK_PROTOCOL_MAX) + return -EINVAL; + if (!net_eq(net, &init_net)) return -EAFNOSUPPORT; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 5d228de07b44..e2ab9681f53a 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -279,6 +279,9 @@ static int inet_create(struct net *net, struct socket *sock, int protocol, 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(); diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index b161144aa8d0..d57813783830 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -109,6 +109,9 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol, 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) diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c index f5d011ad4694..03c8ea9deaf6 100644 --- a/net/irda/af_irda.c +++ b/net/irda/af_irda.c @@ -1106,6 +1106,9 @@ static int irda_create(struct net *net, struct socket *sock, int protocol, IRDA_DEBUG(2, "%s()\n", __func__); + if (protocol < 0 || protocol > SK_PROTOCOL_MAX) + return -EINVAL; + if (net != &init_net) return -EAFNOSUPPORT; |