diff options
| -rw-r--r-- | security/selinux/avc.c | 70 |
1 files changed, 41 insertions, 29 deletions
diff --git a/security/selinux/avc.c b/security/selinux/avc.c index dca1c22d927..6989472d095 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -457,6 +457,42 @@ static void avc_audit_post_callback(struct audit_buffer *ab, void *a) ad->selinux_audit_data.tclass); } +/* This is the slow part of avc audit with big stack footprint */ +static noinline int slow_avc_audit(u32 ssid, u32 tsid, u16 tclass, + u32 requested, u32 audited, u32 denied, + struct av_decision *avd, struct common_audit_data *a, + unsigned flags) +{ + struct common_audit_data stack_data; + + if (!a) { + a = &stack_data; + COMMON_AUDIT_DATA_INIT(a, NONE); + } + + /* + * When in a RCU walk do the audit on the RCU retry. This is because + * the collection of the dname in an inode audit message is not RCU + * safe. Note this may drop some audits when the situation changes + * during retry. However this is logically just as if the operation + * happened a little later. + */ + if ((a->type == LSM_AUDIT_DATA_INODE) && + (flags & MAY_NOT_BLOCK)) + return -ECHILD; + + a->selinux_audit_data.tclass = tclass; + a->selinux_audit_data.requested = requested; + a->selinux_audit_data.ssid = ssid; + a->selinux_audit_data.tsid = tsid; + a->selinux_audit_data.audited = audited; + a->selinux_audit_data.denied = denied; + a->lsm_pre_audit = avc_audit_pre_callback; + a->lsm_post_audit = avc_audit_post_callback; + common_lsm_audit(a); + return 0; +} + /** * avc_audit - Audit the granting or denial of permissions. * @ssid: source security identifier @@ -482,10 +518,9 @@ int avc_audit(u32 ssid, u32 tsid, struct av_decision *avd, int result, struct common_audit_data *a, unsigned flags) { - struct common_audit_data stack_data; u32 denied, audited; denied = requested & ~avd->allowed; - if (denied) { + if (unlikely(denied)) { audited = denied & avd->auditdeny; /* * a->selinux_audit_data.auditdeny is TRICKY! Setting a bit in @@ -511,35 +546,12 @@ int avc_audit(u32 ssid, u32 tsid, audited = denied = requested; else audited = requested & avd->auditallow; - if (!audited) + if (likely(!audited)) return 0; - if (!a) { - a = &stack_data; - COMMON_AUDIT_DATA_INIT(a, NONE); - } - - /* - * When in a RCU walk do the audit on the RCU retry. This is because - * the collection of the dname in an inode audit message is not RCU - * safe. Note this may drop some audits when the situation changes - * during retry. However this is logically just as if the operation - * happened a little later. - */ - if ((a->type == LSM_AUDIT_DATA_INODE) && - (flags & MAY_NOT_BLOCK)) - return -ECHILD; - - a->selinux_audit_data.tclass = tclass; - a->selinux_audit_data.requested = requested; - a->selinux_audit_data.ssid = ssid; - a->selinux_audit_data.tsid = tsid; - a->selinux_audit_data.audited = audited; - a->selinux_audit_data.denied = denied; - a->lsm_pre_audit = avc_audit_pre_callback; - a->lsm_post_audit = avc_audit_post_callback; - common_lsm_audit(a); - return 0; + return slow_avc_audit(ssid, tsid, tclass, + requested, audited, denied, + avd, a, flags); } /** |