diff options
| -rw-r--r-- | security/selinux/avc.c | 28 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 13 | ||||
| -rw-r--r-- | security/selinux/include/avc.h | 4 |
3 files changed, 10 insertions, 35 deletions
diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 6417ed49661f..9322687cb030 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -759,7 +759,11 @@ static void avc_audit_post_callback(struct audit_buffer *ab, void *a) } } -/* This is the slow part of avc audit with big stack footprint */ +/* + * This is the slow part of avc audit with big stack footprint. + * Note that it is non-blocking and can be called from under + * rcu_read_lock(). + */ noinline int slow_avc_audit(struct selinux_state *state, u32 ssid, u32 tsid, u16 tclass, u32 requested, u32 audited, u32 denied, int result, @@ -826,7 +830,7 @@ out: * @ssid,@tsid,@tclass : identifier of an AVC entry * @seqno : sequence number when decision was made * @xpd: extended_perms_decision to be added to the node - * @flags: the AVC_* flags, e.g. AVC_NONBLOCKING, AVC_EXTENDED_PERMS, or 0. + * @flags: the AVC_* flags, e.g. AVC_EXTENDED_PERMS, or 0. * * if a valid AVC entry doesn't exist,this function returns -ENOENT. * if kmalloc() called internal returns NULL, this function returns -ENOMEM. @@ -845,21 +849,6 @@ static int avc_update_node(struct selinux_avc *avc, struct hlist_head *head; spinlock_t *lock; - /* - * If we are in a non-blocking code path, e.g. VFS RCU walk, - * then we must not add permissions to a cache entry - * because we will not audit the denial. Otherwise, - * during the subsequent blocking retry (e.g. VFS ref walk), we - * will find the permissions already granted in the cache entry - * and won't audit anything at all, leading to silent denials in - * permissive mode that only appear when in enforcing mode. - * - * See the corresponding handling of MAY_NOT_BLOCK in avc_audit() - * and selinux_inode_permission(). - */ - if (flags & AVC_NONBLOCKING) - return 0; - node = avc_alloc_node(avc); if (!node) { rc = -ENOMEM; @@ -1120,7 +1109,7 @@ decision: * @tsid: target security identifier * @tclass: target security class * @requested: requested permissions, interpreted based on @tclass - * @flags: AVC_STRICT, AVC_NONBLOCKING, or 0 + * @flags: AVC_STRICT or 0 * @avd: access vector decisions * * Check the AVC to determine whether the @requested permissions are granted @@ -1205,8 +1194,7 @@ int avc_has_perm_flags(struct selinux_state *state, struct av_decision avd; int rc, rc2; - rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested, - (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0, + rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested, 0, &avd); rc2 = avc_audit(state, ssid, tsid, tclass, requested, &avd, rc, diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index fc6a3ab7e179..4e64f681e5d1 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3164,17 +3164,13 @@ static noinline int audit_inode_permission(struct inode *inode, { struct common_audit_data ad; struct inode_security_struct *isec = selinux_inode(inode); - int rc; ad.type = LSM_AUDIT_DATA_INODE; ad.u.inode = inode; - rc = slow_avc_audit(&selinux_state, + return slow_avc_audit(&selinux_state, current_sid(), isec->sid, isec->sclass, perms, audited, denied, result, &ad); - if (rc) - return rc; - return 0; } static int selinux_inode_permission(struct inode *inode, int mask) @@ -3209,8 +3205,7 @@ static int selinux_inode_permission(struct inode *inode, int mask) return PTR_ERR(isec); rc = avc_has_perm_noaudit(&selinux_state, - sid, isec->sid, isec->sclass, perms, - no_block ? AVC_NONBLOCKING : 0, + sid, isec->sid, isec->sclass, perms, 0, &avd); audited = avc_audit_required(perms, &avd, rc, from_access ? FILE__AUDIT_ACCESS : 0, @@ -3218,10 +3213,6 @@ static int selinux_inode_permission(struct inode *inode, int mask) if (likely(!audited)) return rc; - /* fall back to ref-walk if we have to generate audit */ - if (no_block) - return -ECHILD; - rc2 = audit_inode_permission(inode, perms, audited, denied, rc); if (rc2) return rc2; diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h index cf4cc3ef959b..c3bbfc8e8b46 100644 --- a/security/selinux/include/avc.h +++ b/security/selinux/include/avc.h @@ -134,9 +134,6 @@ static inline int avc_audit(struct selinux_state *state, audited = avc_audit_required(requested, avd, result, 0, &denied); if (likely(!audited)) return 0; - /* fall back to ref-walk if we have to generate audit */ - if (flags & MAY_NOT_BLOCK) - return -ECHILD; return slow_avc_audit(state, ssid, tsid, tclass, requested, audited, denied, result, a); @@ -144,7 +141,6 @@ static inline int avc_audit(struct selinux_state *state, #define AVC_STRICT 1 /* Ignore permissive mode. */ #define AVC_EXTENDED_PERMS 2 /* update extended permissions */ -#define AVC_NONBLOCKING 4 /* non blocking */ int avc_has_perm_noaudit(struct selinux_state *state, u32 ssid, u32 tsid, u16 tclass, u32 requested, |