[RFC PATCH V1 05/12] audit: add containerid support for ptrace and signals

From: Richard Guy Briggs
Date: Thu Mar 01 2018 - 14:46:51 EST


Add container ID support to ptrace and signals. In particular, the "op"
field provides a way to label the auxiliary record to which it is
associated.

Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
---
include/linux/audit.h | 16 +++++++++++-----
kernel/audit.c | 12 ++++++++----
kernel/audit.h | 2 ++
kernel/auditsc.c | 19 +++++++++++++++----
4 files changed, 36 insertions(+), 13 deletions(-)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index f10ca1b..ed16bb6 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -35,6 +35,7 @@ struct audit_sig_info {
uid_t uid;
pid_t pid;
char ctx[0];
+ u64 cid;
};

struct audit_buffer;
@@ -155,8 +156,8 @@ extern void audit_log_link_denied(const char *operation,
extern int audit_log_task_context(struct audit_buffer *ab);
extern void audit_log_task_info(struct audit_buffer *ab,
struct task_struct *tsk);
-extern int audit_log_container_info(struct task_struct *tsk,
- struct audit_context *context);
+extern int audit_log_container_info(struct audit_context *context,
+ char *op, u64 containerid);

extern int audit_update_lsm_rules(void);

@@ -208,8 +209,8 @@ static inline int audit_log_task_context(struct audit_buffer *ab)
static inline void audit_log_task_info(struct audit_buffer *ab,
struct task_struct *tsk)
{ }
-static inline int audit_log_container_info(struct task_struct *tsk,
- struct audit_context *context);
+static inline int audit_log_container_info(struct audit_context *context,
+ char *op, u64 containerid);
{ }
#define audit_enabled 0
#endif /* CONFIG_AUDIT */
@@ -598,9 +599,14 @@ static inline bool audit_loginuid_set(struct task_struct *tsk)
return uid_valid(audit_get_loginuid(tsk));
}

+static inline bool cid_valid(u64 containerid)
+{
+ return containerid != INVALID_CID;
+}
+
static inline bool audit_containerid_set(struct task_struct *tsk)
{
- return audit_get_containerid(tsk) != INVALID_CID;
+ return cid_valid(audit_get_containerid(tsk));
}

static inline void audit_log_string(struct audit_buffer *ab, const char *buf)
diff --git a/kernel/audit.c b/kernel/audit.c
index 8dc745f..f5cd0bc 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -142,6 +142,7 @@ struct audit_net {
kuid_t audit_sig_uid = INVALID_UID;
pid_t audit_sig_pid = -1;
u32 audit_sig_sid = 0;
+u64 audit_sig_cid = INVALID_CID;

/* Records can be lost in several ways:
0) [suppressed in audit_alloc]
@@ -1394,6 +1395,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
memcpy(sig_data->ctx, ctx, len);
security_release_secctx(ctx, len);
}
+ sig_data->cid = audit_sig_cid;
audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
sig_data, sizeof(*sig_data) + len);
kfree(sig_data);
@@ -1998,20 +2000,22 @@ void audit_log_session_info(struct audit_buffer *ab)

/*
* audit_log_container_info - report container info
- * @tsk: task to be recorded
* @context: task or local context for record
+ * @op: containerid string description
+ * @containerid: container ID to report
*/
-int audit_log_container_info(struct task_struct *tsk, struct audit_context *context)
+int audit_log_container_info(struct audit_context *context,
+ char *op, u64 containerid)
{
struct audit_buffer *ab;

- if (!audit_containerid_set(tsk))
+ if (!cid_valid(containerid))
return 0;
/* Generate AUDIT_CONTAINER_INFO with container ID */
ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONTAINER_INFO);
if (!ab)
return -ENOMEM;
- audit_log_format(ab, "contid=%llu", audit_get_containerid(tsk));
+ audit_log_format(ab, "op=%s contid=%llu", op, containerid);
audit_log_end(ab);
return 0;
}
diff --git a/kernel/audit.h b/kernel/audit.h
index 683316a..abbabba 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -147,6 +147,7 @@ struct audit_context {
kuid_t target_uid;
unsigned int target_sessionid;
u32 target_sid;
+ u64 target_cid;
char target_comm[TASK_COMM_LEN];

struct audit_tree_refs *trees, *first_trees;
@@ -330,6 +331,7 @@ extern void audit_log_d_path_exe(struct audit_buffer *ab,
extern pid_t audit_sig_pid;
extern kuid_t audit_sig_uid;
extern u32 audit_sig_sid;
+extern u64 audit_sig_cid;

extern int audit_filter(int msgtype, unsigned int listtype);

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 34396cb..0e41884 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -113,6 +113,7 @@ struct audit_aux_data_pids {
kuid_t target_uid[AUDIT_AUX_PIDS];
unsigned int target_sessionid[AUDIT_AUX_PIDS];
u32 target_sid[AUDIT_AUX_PIDS];
+ u64 target_cid[AUDIT_AUX_PIDS];
char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
int pid_count;
};
@@ -1422,21 +1423,27 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
for (aux = context->aux_pids; aux; aux = aux->next) {
struct audit_aux_data_pids *axs = (void *)aux;

- for (i = 0; i < axs->pid_count; i++)
+ for (i = 0; i < axs->pid_count; i++) {
+ char axsn[sizeof("aux0xN ")];
+
+ sprintf(axsn, "aux0x%x", i);
if (audit_log_pid_context(context, axs->target_pid[i],
axs->target_auid[i],
axs->target_uid[i],
axs->target_sessionid[i],
axs->target_sid[i],
- axs->target_comm[i]))
+ axs->target_comm[i])
+ && audit_log_container_info(context, axsn, axs->target_cid[i]))
call_panic = 1;
+ }
}

if (context->target_pid &&
audit_log_pid_context(context, context->target_pid,
context->target_auid, context->target_uid,
context->target_sessionid,
- context->target_sid, context->target_comm))
+ context->target_sid, context->target_comm)
+ && audit_log_container_info(context, "target", context->target_cid))
call_panic = 1;

if (context->pwd.dentry && context->pwd.mnt) {
@@ -1456,7 +1463,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts

audit_log_proctitle(tsk, context);

- audit_log_container_info(tsk, context);
+ audit_log_container_info(context, "task", audit_get_containerid(tsk));

/* Send end of event record to help user space know we are finished */
ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
@@ -2354,6 +2361,7 @@ void __audit_ptrace(struct task_struct *t)
context->target_uid = task_uid(t);
context->target_sessionid = audit_get_sessionid(t);
security_task_getsecid(t, &context->target_sid);
+ context->target_cid = audit_get_containerid(t);
memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
}

@@ -2381,6 +2389,7 @@ int audit_signal_info(int sig, struct task_struct *t)
else
audit_sig_uid = uid;
security_task_getsecid(tsk, &audit_sig_sid);
+ audit_sig_cid = audit_get_containerid(tsk);
}

if (!audit_signals || audit_dummy_context())
@@ -2394,6 +2403,7 @@ int audit_signal_info(int sig, struct task_struct *t)
ctx->target_uid = t_uid;
ctx->target_sessionid = audit_get_sessionid(t);
security_task_getsecid(t, &ctx->target_sid);
+ ctx->target_cid = audit_get_containerid(t);
memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
return 0;
}
@@ -2415,6 +2425,7 @@ int audit_signal_info(int sig, struct task_struct *t)
axp->target_uid[axp->pid_count] = t_uid;
axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
+ axp->target_cid[axp->pid_count] = audit_get_containerid(t);
memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
axp->pid_count++;

--
1.8.3.1