diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h index 9b6a973f4cc3..cd2d8279a5e4 100644 --- a/include/uapi/linux/audit.h +++ b/include/uapi/linux/audit.h @@ -333,14 +333,15 @@ enum { }; /* Status symbols */ - /* Mask values */ -#define AUDIT_STATUS_ENABLED 0x0001 -#define AUDIT_STATUS_FAILURE 0x0002 -#define AUDIT_STATUS_PID 0x0004 + /* Mask values */ +#define AUDIT_STATUS_ENABLED 0x0001 +#define AUDIT_STATUS_FAILURE 0x0002 +#define AUDIT_STATUS_PID 0x0004 #define AUDIT_STATUS_RATE_LIMIT 0x0008 -#define AUDIT_STATUS_BACKLOG_LIMIT 0x0010 -#define AUDIT_STATUS_BACKLOG_WAIT_TIME 0x0020 -#define AUDIT_STATUS_LOST 0x0040 +#define AUDIT_STATUS_BACKLOG_LIMIT 0x0010 +#define AUDIT_STATUS_BACKLOG_WAIT_TIME 0x0020 +#define AUDIT_STATUS_LOST 0x0040 +#define AUDIT_STATUS_BACKLOG_WAIT_TIME_ACTUAL 0x0080 #define AUDIT_FEATURE_BITMAP_BACKLOG_LIMIT 0x00000001 #define AUDIT_FEATURE_BITMAP_BACKLOG_WAIT_TIME 0x00000002 @@ -467,6 +468,9 @@ struct audit_status { __u32 feature_bitmap; /* bitmap of kernel audit features */ }; __u32 backlog_wait_time;/* message queue wait timeout */ + __u32 backlog_wait_time_actual;/* time spent waiting while + * message limit exceeded + */ }; struct audit_features { diff --git a/kernel/audit.c b/kernel/audit.c index a2f3e34aa724..d72663ac248c 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -136,6 +136,11 @@ u32 audit_sig_sid = 0; */ static atomic_t audit_lost = ATOMIC_INIT(0); +/* Monotonically increasing sum of time the kernel has spent + * waiting while the backlog limit is exceeded. + */ +static atomic_t audit_backlog_wait_time_actual = ATOMIC_INIT(0); + /* Hash for inode-based rules */ struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS]; @@ -1201,17 +1206,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) case AUDIT_GET: { struct audit_status s; memset(&s, 0, sizeof(s)); - s.enabled = audit_enabled; - s.failure = audit_failure; + s.enabled = audit_enabled; + s.failure = audit_failure; /* NOTE: use pid_vnr() so the PID is relative to the current * namespace */ - s.pid = auditd_pid_vnr(); - s.rate_limit = audit_rate_limit; - s.backlog_limit = audit_backlog_limit; - s.lost = atomic_read(&audit_lost); - s.backlog = skb_queue_len(&audit_queue); - s.feature_bitmap = AUDIT_FEATURE_BITMAP_ALL; - s.backlog_wait_time = audit_backlog_wait_time; + s.pid = auditd_pid_vnr(); + s.rate_limit = audit_rate_limit; + s.backlog_limit = audit_backlog_limit; + s.lost = atomic_read(&audit_lost); + s.backlog = skb_queue_len(&audit_queue); + s.feature_bitmap = AUDIT_FEATURE_BITMAP_ALL; + s.backlog_wait_time = audit_backlog_wait_time; + s.backlog_wait_time_actual = atomic_read(&audit_backlog_wait_time_actual); audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s)); break; } @@ -1315,6 +1321,12 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) audit_log_config_change("lost", 0, lost, 1); return lost; } + if (s.mask == AUDIT_STATUS_BACKLOG_WAIT_TIME_ACTUAL) { + u32 actual = atomic_xchg(&audit_backlog_wait_time_actual, 0); + + audit_log_config_change("backlog_wait_time_actual", 0, actual, 1); + return actual; + } break; } case AUDIT_GET_FEATURE: @@ -1826,12 +1838,15 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, /* sleep if we are allowed and we haven't exhausted our * backlog wait limit */ if (gfpflags_allow_blocking(gfp_mask) && (stime > 0)) { + long rtime = stime; + DECLARE_WAITQUEUE(wait, current); add_wait_queue_exclusive(&audit_backlog_wait, &wait); set_current_state(TASK_UNINTERRUPTIBLE); - stime = schedule_timeout(stime); + stime = schedule_timeout(rtime); + atomic_add(rtime - stime, &audit_backlog_wait_time_actual); remove_wait_queue(&audit_backlog_wait, &wait); } else { if (audit_rate_check() && printk_ratelimit())