[PATCH 3.8 19/91] proc connector: fix info leaks

From: Kamal Mostafa
Date: Thu Nov 07 2013 - 21:37:46 EST


3.8.13.13 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Mathias Krause <minipli@xxxxxxxxxxxxxx>

[ 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.

Signed-off-by: Mathias Krause <minipli@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
[ kamal: backport to 3.8 (context) ]
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/connector/cn_proc.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c
index 1110478..1b1d255 100644
--- a/drivers/connector/cn_proc.c
+++ b/drivers/connector/cn_proc.c
@@ -65,6 +65,7 @@ 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);
@@ -80,6 +81,7 @@ 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);
}
@@ -96,6 +98,7 @@ 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);
@@ -106,6 +109,7 @@ 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);
}

@@ -122,6 +126,7 @@ 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;
@@ -145,6 +150,7 @@ 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);
}

@@ -160,6 +166,7 @@ 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);
@@ -170,6 +177,7 @@ 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);
}

@@ -185,6 +193,7 @@ void proc_ptrace_connector(struct task_struct *task, int ptrace_id)

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);
@@ -203,6 +212,7 @@ void proc_ptrace_connector(struct task_struct *task, int ptrace_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);
}

@@ -218,6 +228,7 @@ void proc_comm_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);
@@ -229,6 +240,7 @@ void proc_comm_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);
}

@@ -244,6 +256,7 @@ 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 */
put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns);
@@ -256,6 +269,8 @@ 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 */
+ msg->flags = 0; /* not used */
cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
}

@@ -279,6 +294,7 @@ 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);
@@ -288,6 +304,7 @@ 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);
}

--
1.8.1.2

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