[PATCH AUTOSEL for 4.9 31/33] audit: ensure that 'audit=1' actually enables audit for PID 1

From: alexander . levin
Date: Sat Dec 02 2017 - 11:04:54 EST


From: Paul Moore <paul@xxxxxxxxxxxxxx>

[ Upstream commit 173743dd99a49c956b124a74c8aacb0384739a4c ]

Prior to this patch we enabled audit in audit_init(), which is too
late for PID 1 as the standard initcalls are run after the PID 1 task
is forked. This means that we never allocate an audit_context (see
audit_alloc()) for PID 1 and therefore miss a lot of audit events
generated by PID 1.

This patch enables audit as early as possible to help ensure that when
PID 1 is forked it can allocate an audit_context if required.

Reviewed-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
kernel/audit.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/audit.c b/kernel/audit.c
index f1ca11613379..da4e7c0e36f7 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -79,13 +79,13 @@ static int audit_initialized;
#define AUDIT_OFF 0
#define AUDIT_ON 1
#define AUDIT_LOCKED 2
-u32 audit_enabled;
-u32 audit_ever_enabled;
+u32 audit_enabled = AUDIT_OFF;
+u32 audit_ever_enabled = !!AUDIT_OFF;

EXPORT_SYMBOL_GPL(audit_enabled);

/* Default state when kernel boots without any parameters. */
-static u32 audit_default;
+static u32 audit_default = AUDIT_OFF;

/* If auditing cannot proceed, audit_failure selects what happens. */
static u32 audit_failure = AUDIT_FAIL_PRINTK;
@@ -1199,8 +1199,6 @@ static int __init audit_init(void)
skb_queue_head_init(&audit_skb_queue);
skb_queue_head_init(&audit_skb_hold_queue);
audit_initialized = AUDIT_INITIALIZED;
- audit_enabled = audit_default;
- audit_ever_enabled |= !!audit_default;

audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");

@@ -1217,6 +1215,8 @@ static int __init audit_enable(char *str)
audit_default = !!simple_strtol(str, NULL, 0);
if (!audit_default)
audit_initialized = AUDIT_DISABLED;
+ audit_enabled = audit_default;
+ audit_ever_enabled = !!audit_enabled;

pr_info("%s\n", audit_default ?
"enabled (after initialization)" : "disabled (until reboot)");
--
2.11.0