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| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2015-12-14 22:03:39 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-12-14 16:09:30 -0500 |
| commit | 79462ad02e861803b3840cc782248c7359451cd9 (patch) | |
| tree | dd000edadb23174c68e34fc3929d6368b2bd9c37 /net/ipv4 | |
| parent | 20b08e1a793d898f0f13040d5418ee0955f678cf (diff) | |
| download | linux-79462ad02e861803b3840cc782248c7359451cd9.tar.gz linux-79462ad02e861803b3840cc782248c7359451cd9.tar.bz2 linux-79462ad02e861803b3840cc782248c7359451cd9.zip | |
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>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/af_inet.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 11c4ca13ec3b..5c5db6636704 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -257,6 +257,9 @@ 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; + sock->state = SS_UNCONNECTED; /* Look for the requested type/protocol pair. */ |