[ 030/143] proc connector: fix info leaks

Willy Tarreau
2014-05-12T02:29:18Z

From: Mathias Krause <minipli@googlemail.com>

[ Upstream commit e727ca82e0e9616ab4844301e6bae60ca7327682 ]

Initialize event_data for all possible message types to prevent leaking
kernel stack contents to userland (up to 20 bytes). Also set the flags
member of the connector message to 0 to prevent leaking two more stack
bytes this way.

Cc: stable@vger.kernel.org
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/connector/cn_proc.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c
index 6069790..3a2587a 100644
--- a/drivers/connector/cn_proc.c
+++ b/drivers/connector/cn_proc.c
@@ -59,6 +59,7 @@ void proc_fork_connector(struct task_struct *task)

msg = (struct cn_msg*)buffer;
ev = (struct proc_event*)msg->data;
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
get_seq(&msg->seq, &ev->cpu);
ktime_get_ts(&ts); /* get high res monotonic timestamp */
put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
@@ -71,6 +72,7 @@ void proc_fork_connector(struct task_struct *task)
memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
msg->ack = 0; /* not used */
msg->len = sizeof(*ev);
+ msg->flags = 0; /* not used */
/* If cn_netlink_send() failed, the data is not sent */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}
@@ -87,6 +89,7 @@ void proc_exec_connector(struct task_struct *task)

msg = (struct cn_msg*)buffer;
ev = (struct proc_event*)msg->data;
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
get_seq(&msg->seq, &ev->cpu);
ktime_get_ts(&ts); /* get high res monotonic timestamp */
put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
@@ -97,6 +100,7 @@ void proc_exec_connector(struct task_struct *task)
memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
msg->ack = 0; /* not used */
msg->len = sizeof(*ev);
+ msg->flags = 0; /* not used */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}

@@ -113,6 +117,7 @@ void proc_id_connector(struct task_struct *task, int which_id)

msg = (struct cn_msg*)buffer;
ev = (struct proc_event*)msg->data;
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
ev->what = which_id;
ev->event_data.id.process_pid = task->pid;
ev->event_data.id.process_tgid = task->tgid;
@@ -136,6 +141,7 @@ void proc_id_connector(struct task_struct *task, int which_id)
memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
msg->ack = 0; /* not used */
msg->len = sizeof(*ev);
+ msg->flags = 0; /* not used */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}

@@ -151,6 +157,7 @@ void proc_sid_connector(struct task_struct *task)

msg = (struct cn_msg *)buffer;
ev = (struct proc_event *)msg->data;
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
get_seq(&msg->seq, &ev->cpu);
ktime_get_ts(&ts); /* get high res monotonic timestamp */
put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
@@ -161,6 +168,7 @@ void proc_sid_connector(struct task_struct *task)
memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
msg->ack = 0; /* not used */
msg->len = sizeof(*ev);
+ msg->flags = 0; /* not used */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}

@@ -176,8 +184,10 @@ void proc_exit_connector(struct task_struct *task)

msg = (struct cn_msg*)buffer;
ev = (struct proc_event*)msg->data;
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
get_seq(&msg->seq, &ev->cpu);
ktime_get_ts(&ts); /* get high res monotonic timestamp */
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
ev->what = PROC_EVENT_EXIT;
ev->event_data.exit.process_pid = task->pid;
@@ -188,6 +198,7 @@ void proc_exit_connector(struct task_struct *task)
memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
msg->ack = 0; /* not used */
msg->len = sizeof(*ev);
+ msg->flags = 0; /* not used */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}

@@ -211,6 +222,7 @@ static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)

msg = (struct cn_msg*)buffer;
ev = (struct proc_event*)msg->data;
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
msg->seq = rcvd_seq;
ktime_get_ts(&ts); /* get high res monotonic timestamp */
put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
@@ -220,6 +232,7 @@ static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
msg->ack = rcvd_ack + 1;
msg->len = sizeof(*ev);
+ msg->flags = 0; /* not used */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}

@@ -249,6 +262,7 @@ static void cn_proc_mcast_ctl(struct cn_msg *msg,
break;
}
cn_proc_ack(err, msg->seq, msg->ack);
+ msg->flags = 0; /* not used */
}

/*
@@ -269,3 +283,5 @@ static int __init cn_proc_init(void)
}

module_init(cn_proc_init);
+ memset(&ev->event_data, 0, sizeof(ev->event_data));
+ msg->flags = 0; /* not used */
--
1.7.12.2.21.g234cd45.dirty