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| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2015-12-14 22:03:39 +0100 |
|---|---|---|
| committer | Willy Tarreau <w@1wt.eu> | 2016-01-29 22:12:42 +0100 |
| commit | be9b6c294668e0686e8ac69f617c6c1963a91472 (patch) | |
| tree | 6e62b5e47a0a287e48fa68d4cc5de4674b9bcee3 | |
| parent | 67fbe958a57bfa443b2e4f7c3a15d3e109082e4b (diff) | |
| download | linux-stable-be9b6c294668e0686e8ac69f617c6c1963a91472.tar.gz linux-stable-be9b6c294668e0686e8ac69f617c6c1963a91472.tar.bz2 linux-stable-be9b6c294668e0686e8ac69f617c6c1963a91472.zip | |
net: add validation for the socket syscall protocol argument
commit 79462ad02e861803b3840cc782248c7359451cd9 upstream.
éæ°¸å 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: éæ°¸å <guoyonggang@360.cn>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 2.6.32: open-code U8_MAX; adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Willy Tarreau <w@1wt.eu>
| -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 78adf52ca278..0de7d227704f 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -230,6 +230,7 @@ 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_rcvbuf; diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 6b9d62b5d820..c1cf94025628 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -805,6 +805,9 @@ 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 != &init_net) return -EAFNOSUPPORT; diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c index 5df7b5453556..7bb3fc397eea 100644 --- a/net/decnet/af_decnet.c +++ b/net/decnet/af_decnet.c @@ -679,6 +679,9 @@ 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 != &init_net) return -EAFNOSUPPORT; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index d1992a4d166a..2b9b83e1602f 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -273,6 +273,9 @@ 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 835590d68876..02d6175b42f7 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -107,6 +107,9 @@ 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 7cb7613d2ec7..30ffff85155f 100644 --- a/net/irda/af_irda.c +++ b/net/irda/af_irda.c @@ -1069,6 +1069,9 @@ 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; |