X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=security%2Fselinux%2Favc.c;h=114b4b4c97b23b9acdf25e92d1b250f78167457d;hb=9e113e0014204bfb44a2baa29b2a141ede41b074;hp=187964e88af1513f79940e025a2353407eff107a;hpb=bdc08942897f6be33d00bb659761516f4652836d;p=linux-2.6-omap-h63xx.git diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 187964e88af..114b4b4c97b 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -2,16 +2,16 @@ * Implementation of the kernel access vector cache (AVC). * * Authors: Stephen Smalley, - * James Morris + * James Morris * * Update: KaiGai, Kohei - * Replaced the avc_lock spinlock by RCU. + * Replaced the avc_lock spinlock by RCU. * * Copyright (C) 2003 Red Hat, Inc., James Morris * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2, - * as published by the Free Software Foundation. + * as published by the Free Software Foundation. */ #include #include @@ -44,7 +44,7 @@ static const char *class_to_string[] = { #undef S_ }; -#define TB_(s) static const char * s [] = { +#define TB_(s) static const char *s[] = { #define TE_(s) }; #define S_(s) s, #include "common_perm_to_string.h" @@ -72,7 +72,7 @@ const struct selinux_class_perm selinux_class_perm = { #define AVC_CACHE_RECLAIM 16 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS -#define avc_cache_stats_incr(field) \ +#define avc_cache_stats_incr(field) \ do { \ per_cpu(avc_cache_stats, get_cpu()).field++; \ put_cpu(); \ @@ -92,7 +92,7 @@ struct avc_entry { struct avc_node { struct avc_entry ae; struct list_head list; - struct rcu_head rhead; + struct rcu_head rhead; }; struct avc_cache { @@ -105,8 +105,8 @@ struct avc_cache { struct avc_callback_node { int (*callback) (u32 event, u32 ssid, u32 tsid, - u16 tclass, u32 perms, - u32 *out_retained); + u16 tclass, u32 perms, + u32 *out_retained); u32 events; u32 ssid; u32 tsid; @@ -202,7 +202,7 @@ static void avc_dump_query(struct audit_buffer *ab, u32 ssid, u32 tsid, u16 tcla char *scontext; u32 scontext_len; - rc = security_sid_to_context(ssid, &scontext, &scontext_len); + rc = security_sid_to_context(ssid, &scontext, &scontext_len); if (rc) audit_log_format(ab, "ssid=%d", ssid); else { @@ -306,12 +306,13 @@ static inline int avc_reclaim_node(void) int hvalue, try, ecx; unsigned long flags; - for (try = 0, ecx = 0; try < AVC_CACHE_SLOTS; try++ ) { + for (try = 0, ecx = 0; try < AVC_CACHE_SLOTS; try++) { hvalue = atomic_inc_return(&avc_cache.lru_hint) & (AVC_CACHE_SLOTS - 1); if (!spin_trylock_irqsave(&avc_cache.slots_lock[hvalue], flags)) continue; + rcu_read_lock(); list_for_each_entry(node, &avc_cache.slots[hvalue], list) { if (atomic_dec_and_test(&node->ae.used)) { /* Recently Unused */ @@ -319,11 +320,13 @@ static inline int avc_reclaim_node(void) avc_cache_stats_incr(reclaims); ecx++; if (ecx >= AVC_CACHE_RECLAIM) { + rcu_read_unlock(); spin_unlock_irqrestore(&avc_cache.slots_lock[hvalue], flags); goto out; } } } + rcu_read_unlock(); spin_unlock_irqrestore(&avc_cache.slots_lock[hvalue], flags); } out: @@ -426,7 +429,7 @@ static int avc_latest_notif_update(int seqno, int is_insert) spin_lock_irqsave(¬if_lock, flag); if (is_insert) { if (seqno < avc_cache.latest_notif) { - printk(KERN_WARNING "avc: seqno %d < latest_notif %d\n", + printk(KERN_WARNING "SELinux: avc: seqno %d < latest_notif %d\n", seqno, avc_cache.latest_notif); ret = -EAGAIN; } @@ -475,7 +478,7 @@ static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass, struct avc_en if (pos->ae.ssid == ssid && pos->ae.tsid == tsid && pos->ae.tclass == tclass) { - avc_node_replace(node, pos); + avc_node_replace(node, pos); goto found; } } @@ -526,8 +529,8 @@ static inline void avc_print_ipv4_addr(struct audit_buffer *ab, __be32 addr, * before calling the auditing code. */ void avc_audit(u32 ssid, u32 tsid, - u16 tclass, u32 requested, - struct av_decision *avd, int result, struct avc_audit_data *a) + u16 tclass, u32 requested, + struct av_decision *avd, int result, struct avc_audit_data *a) { struct task_struct *tsk = current; struct inode *inode = NULL; @@ -541,7 +544,7 @@ void avc_audit(u32 ssid, u32 tsid, return; } else if (result) { audited = denied = requested; - } else { + } else { audited = requested; if (!(audited & avd->auditallow)) return; @@ -551,7 +554,7 @@ void avc_audit(u32 ssid, u32 tsid, if (!ab) return; /* audit_panic has been called */ audit_log_format(ab, "avc: %s ", denied ? "denied" : "granted"); - avc_dump_av(ab, tclass,audited); + avc_dump_av(ab, tclass, audited); audit_log_format(ab, " for "); if (a && a->tsk) tsk = a->tsk; @@ -643,11 +646,11 @@ void avc_audit(u32 ssid, u32 tsid, if (*p) audit_log_untrustedstring(ab, p); else - audit_log_hex(ab, p, len); + audit_log_n_hex(ab, p, len); break; } } - + switch (a->u.net.family) { case AF_INET: avc_print_ipv4_addr(ab, a->u.net.v4info.saddr, @@ -702,10 +705,10 @@ void avc_audit(u32 ssid, u32 tsid, * -%ENOMEM if insufficient memory exists to add the callback. */ int avc_add_callback(int (*callback)(u32 event, u32 ssid, u32 tsid, - u16 tclass, u32 perms, - u32 *out_retained), - u32 events, u32 ssid, u32 tsid, - u16 tclass, u32 perms) + u16 tclass, u32 perms, + u32 *out_retained), + u32 events, u32 ssid, u32 tsid, + u16 tclass, u32 perms) { struct avc_callback_node *c; int rc = 0; @@ -759,10 +762,10 @@ static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass) hvalue = avc_hash(ssid, tsid, tclass); spin_lock_irqsave(&avc_cache.slots_lock[hvalue], flag); - list_for_each_entry(pos, &avc_cache.slots[hvalue], list){ - if ( ssid==pos->ae.ssid && - tsid==pos->ae.tsid && - tclass==pos->ae.tclass ){ + list_for_each_entry(pos, &avc_cache.slots[hvalue], list) { + if (ssid == pos->ae.ssid && + tsid == pos->ae.tsid && + tclass == pos->ae.tclass){ orig = pos; break; } @@ -821,15 +824,21 @@ int avc_ss_reset(u32 seqno) for (i = 0; i < AVC_CACHE_SLOTS; i++) { spin_lock_irqsave(&avc_cache.slots_lock[i], flag); + /* + * With preemptable RCU, the outer spinlock does not + * prevent RCU grace periods from ending. + */ + rcu_read_lock(); list_for_each_entry(node, &avc_cache.slots[i], list) avc_node_delete(node); + rcu_read_unlock(); spin_unlock_irqrestore(&avc_cache.slots_lock[i], flag); } for (c = avc_callbacks; c; c = c->next) { if (c->events & AVC_CALLBACK_RESET) { tmprc = c->callback(AVC_CALLBACK_RESET, - 0, 0, 0, 0, NULL); + 0, 0, 0, 0, NULL); /* save the first error encountered for the return value and continue processing the callbacks */ if (!rc) @@ -871,16 +880,18 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, int rc = 0; u32 denied; + BUG_ON(!requested); + rcu_read_lock(); node = avc_lookup(ssid, tsid, tclass, requested); if (!node) { rcu_read_unlock(); - rc = security_compute_av(ssid,tsid,tclass,requested,&entry.avd); + rc = security_compute_av(ssid, tsid, tclass, requested, &entry.avd); if (rc) goto out; rcu_read_lock(); - node = avc_insert(ssid,tsid,tclass,&entry); + node = avc_insert(ssid, tsid, tclass, &entry); } p_ae = node ? &node->ae : &entry; @@ -890,13 +901,14 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, denied = requested & ~(p_ae->avd.allowed); - if (!requested || denied) { - if (selinux_enforcing || (flags & AVC_STRICT)) + if (denied) { + if (flags & AVC_STRICT) rc = -EACCES; + else if (!selinux_enforcing || security_permissive_sid(ssid)) + avc_update_node(AVC_CALLBACK_GRANT, requested, ssid, + tsid, tclass); else - if (node) - avc_update_node(AVC_CALLBACK_GRANT,requested, - ssid,tsid,tclass); + rc = -EACCES; } rcu_read_unlock(); @@ -921,7 +933,7 @@ out: * another -errno upon other errors. */ int avc_has_perm(u32 ssid, u32 tsid, u16 tclass, - u32 requested, struct avc_audit_data *auditdata) + u32 requested, struct avc_audit_data *auditdata) { struct av_decision avd; int rc;