diff options
Diffstat (limited to 'security/selinux/avc.c')
-rw-r--r-- | security/selinux/avc.c | 51 |
1 files changed, 34 insertions, 17 deletions
diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 9da6420e205..3d2715fd35e 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -38,11 +38,7 @@ #define AVC_CACHE_RECLAIM 16 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS -#define avc_cache_stats_incr(field) \ -do { \ - per_cpu(avc_cache_stats, get_cpu()).field++; \ - put_cpu(); \ -} while (0) +#define avc_cache_stats_incr(field) this_cpu_inc(avc_cache_stats.field) #else #define avc_cache_stats_incr(field) do {} while (0) #endif @@ -347,11 +343,10 @@ static struct avc_node *avc_lookup(u32 ssid, u32 tsid, u16 tclass) node = avc_search_node(ssid, tsid, tclass); if (node) - avc_cache_stats_incr(hits); - else - avc_cache_stats_incr(misses); + return node; - return node; + avc_cache_stats_incr(misses); + return NULL; } static int avc_latest_notif_update(int seqno, int is_insert) @@ -471,6 +466,7 @@ static void avc_audit_post_callback(struct audit_buffer *ab, void *a) * @avd: access vector decisions * @result: result from avc_has_perm_noaudit * @a: auxiliary audit data + * @flags: VFS walk flags * * Audit the granting or denial of permissions in accordance * with the policy. This function is typically called by @@ -481,9 +477,10 @@ static void avc_audit_post_callback(struct audit_buffer *ab, void *a) * be performed under a lock, to allow the lock to be released * before calling the auditing code. */ -void avc_audit(u32 ssid, u32 tsid, +int avc_audit(u32 ssid, u32 tsid, u16 tclass, u32 requested, - struct av_decision *avd, int result, struct common_audit_data *a) + struct av_decision *avd, int result, struct common_audit_data *a, + unsigned flags) { struct common_audit_data stack_data; u32 denied, audited; @@ -515,11 +512,24 @@ void avc_audit(u32 ssid, u32 tsid, else audited = requested & avd->auditallow; if (!audited) - return; + 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_FS) && + (flags & IPERM_FLAG_RCU)) + return -ECHILD; + a->selinux_audit_data.tclass = tclass; a->selinux_audit_data.requested = requested; a->selinux_audit_data.ssid = ssid; @@ -529,6 +539,7 @@ void avc_audit(u32 ssid, u32 tsid, a->lsm_pre_audit = avc_audit_pre_callback; a->lsm_post_audit = avc_audit_post_callback; common_lsm_audit(a); + return 0; } /** @@ -753,7 +764,7 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, rcu_read_lock(); node = avc_lookup(ssid, tsid, tclass); - if (!node) { + if (unlikely(!node)) { rcu_read_unlock(); if (in_avd) @@ -793,6 +804,7 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, * @tclass: target security class * @requested: requested permissions, interpreted based on @tclass * @auditdata: auxiliary audit data + * @flags: VFS walk flags * * Check the AVC to determine whether the @requested permissions are granted * for the SID pair (@ssid, @tsid), interpreting the permissions @@ -802,14 +814,19 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, * permissions are granted, -%EACCES if any permissions are denied, or * another -errno upon other errors. */ -int avc_has_perm(u32 ssid, u32 tsid, u16 tclass, - u32 requested, struct common_audit_data *auditdata) +int avc_has_perm_flags(u32 ssid, u32 tsid, u16 tclass, + u32 requested, struct common_audit_data *auditdata, + unsigned flags) { struct av_decision avd; - int rc; + int rc, rc2; rc = avc_has_perm_noaudit(ssid, tsid, tclass, requested, 0, &avd); - avc_audit(ssid, tsid, tclass, requested, &avd, rc, auditdata); + + rc2 = avc_audit(ssid, tsid, tclass, requested, &avd, rc, auditdata, + flags); + if (rc2) + return rc2; return rc; } |