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Diffstat (limited to 'security/selinux/hooks.c')
-rw-r--r--security/selinux/hooks.c201
1 files changed, 124 insertions, 77 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 564079c5c49d..9e591e5989be 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -126,6 +126,7 @@ int selinux_enabled = 1;
#endif
static struct kmem_cache *sel_inode_cache;
+static struct kmem_cache *file_security_cache;
/**
* selinux_secmark_enabled - Check to see if SECMARK is currently enabled
@@ -254,10 +255,21 @@ static void inode_free_security(struct inode *inode)
struct inode_security_struct *isec = inode->i_security;
struct superblock_security_struct *sbsec = inode->i_sb->s_security;
- spin_lock(&sbsec->isec_lock);
- if (!list_empty(&isec->list))
+ /*
+ * As not all inode security structures are in a list, we check for
+ * empty list outside of the lock to make sure that we won't waste
+ * time taking a lock doing nothing.
+ *
+ * The list_del_init() function can be safely called more than once.
+ * It should not be possible for this function to be called with
+ * concurrent list_add(), but for better safety against future changes
+ * in the code, we use list_empty_careful() here.
+ */
+ if (!list_empty_careful(&isec->list)) {
+ spin_lock(&sbsec->isec_lock);
list_del_init(&isec->list);
- spin_unlock(&sbsec->isec_lock);
+ spin_unlock(&sbsec->isec_lock);
+ }
/*
* The inode may still be referenced in a path walk and
@@ -276,7 +288,7 @@ static int file_alloc_security(struct file *file)
struct file_security_struct *fsec;
u32 sid = current_sid();
- fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
+ fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
if (!fsec)
return -ENOMEM;
@@ -291,7 +303,7 @@ static void file_free_security(struct file *file)
{
struct file_security_struct *fsec = file->f_security;
file->f_security = NULL;
- kfree(fsec);
+ kmem_cache_free(file_security_cache, fsec);
}
static int superblock_alloc_security(struct super_block *sb)
@@ -663,10 +675,9 @@ static int selinux_set_mnt_opts(struct super_block *sb,
if (flags[i] == SBLABEL_MNT)
continue;
- rc = security_context_to_sid(mount_options[i],
- strlen(mount_options[i]), &sid, GFP_KERNEL);
+ rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
if (rc) {
- printk(KERN_WARNING "SELinux: security_context_to_sid"
+ printk(KERN_WARNING "SELinux: security_context_str_to_sid"
"(%s) failed for (dev %s, type %s) errno=%d\n",
mount_options[i], sb->s_id, name, rc);
goto out;
@@ -1100,7 +1111,7 @@ static void selinux_write_opts(struct seq_file *m,
seq_puts(m, prefix);
if (has_comma)
seq_putc(m, '\"');
- seq_puts(m, opts->mnt_opts[i]);
+ seq_escape(m, opts->mnt_opts[i], "\"\n\\");
if (has_comma)
seq_putc(m, '\"');
}
@@ -1698,6 +1709,32 @@ out:
return rc;
}
+/*
+ * Determine the label for an inode that might be unioned.
+ */
+static int selinux_determine_inode_label(const struct inode *dir,
+ const struct qstr *name,
+ u16 tclass,
+ u32 *_new_isid)
+{
+ const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
+ const struct inode_security_struct *dsec = dir->i_security;
+ const struct task_security_struct *tsec = current_security();
+
+ if ((sbsec->flags & SE_SBINITIALIZED) &&
+ (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
+ *_new_isid = sbsec->mntpoint_sid;
+ } else if ((sbsec->flags & SBLABEL_MNT) &&
+ tsec->create_sid) {
+ *_new_isid = tsec->create_sid;
+ } else {
+ return security_transition_sid(tsec->sid, dsec->sid, tclass,
+ name, _new_isid);
+ }
+
+ return 0;
+}
+
/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
struct dentry *dentry,
@@ -1714,7 +1751,6 @@ static int may_create(struct inode *dir,
sbsec = dir->i_sb->s_security;
sid = tsec->sid;
- newsid = tsec->create_sid;
ad.type = LSM_AUDIT_DATA_DENTRY;
ad.u.dentry = dentry;
@@ -1725,12 +1761,10 @@ static int may_create(struct inode *dir,
if (rc)
return rc;
- if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
- rc = security_transition_sid(sid, dsec->sid, tclass,
- &dentry->d_name, &newsid);
- if (rc)
- return rc;
- }
+ rc = selinux_determine_inode_label(dir, &dentry->d_name, tclass,
+ &newsid);
+ if (rc)
+ return rc;
rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
if (rc)
@@ -2583,15 +2617,12 @@ static int selinux_sb_remount(struct super_block *sb, void *data)
for (i = 0; i < opts.num_mnt_opts; i++) {
u32 sid;
- size_t len;
if (flags[i] == SBLABEL_MNT)
continue;
- len = strlen(mount_options[i]);
- rc = security_context_to_sid(mount_options[i], len, &sid,
- GFP_KERNEL);
+ rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
if (rc) {
- printk(KERN_WARNING "SELinux: security_context_to_sid"
+ printk(KERN_WARNING "SELinux: security_context_str_to_sid"
"(%s) failed for (dev %s, type %s) errno=%d\n",
mount_options[i], sb->s_id, sb->s_type->name, rc);
goto out_free_opts;
@@ -2704,32 +2735,14 @@ static int selinux_dentry_init_security(struct dentry *dentry, int mode,
struct qstr *name, void **ctx,
u32 *ctxlen)
{
- const struct cred *cred = current_cred();
- struct task_security_struct *tsec;
- struct inode_security_struct *dsec;
- struct superblock_security_struct *sbsec;
- struct inode *dir = d_backing_inode(dentry->d_parent);
u32 newsid;
int rc;
- tsec = cred->security;
- dsec = dir->i_security;
- sbsec = dir->i_sb->s_security;
-
- if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
- newsid = tsec->create_sid;
- } else {
- rc = security_transition_sid(tsec->sid, dsec->sid,
- inode_mode_to_security_class(mode),
- name,
- &newsid);
- if (rc) {
- printk(KERN_WARNING
- "%s: security_transition_sid failed, rc=%d\n",
- __func__, -rc);
- return rc;
- }
- }
+ rc = selinux_determine_inode_label(d_inode(dentry->d_parent), name,
+ inode_mode_to_security_class(mode),
+ &newsid);
+ if (rc)
+ return rc;
return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}
@@ -2752,22 +2765,12 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
sid = tsec->sid;
newsid = tsec->create_sid;
- if ((sbsec->flags & SE_SBINITIALIZED) &&
- (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
- newsid = sbsec->mntpoint_sid;
- else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
- rc = security_transition_sid(sid, dsec->sid,
- inode_mode_to_security_class(inode->i_mode),
- qstr, &newsid);
- if (rc) {
- printk(KERN_WARNING "%s: "
- "security_transition_sid failed, rc=%d (dev=%s "
- "ino=%ld)\n",
- __func__,
- -rc, inode->i_sb->s_id, inode->i_ino);
- return rc;
- }
- }
+ rc = selinux_determine_inode_label(
+ dir, qstr,
+ inode_mode_to_security_class(inode->i_mode),
+ &newsid);
+ if (rc)
+ return rc;
/* Possibly defer initialization to selinux_complete_init. */
if (sbsec->flags & SE_SBINITIALIZED) {
@@ -2940,7 +2943,8 @@ static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
return dentry_has_perm(cred, dentry, FILE__SETATTR);
- if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
+ if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
+ && !(ia_valid & ATTR_FILE))
av |= FILE__OPEN;
return dentry_has_perm(cred, dentry, av);
@@ -3160,7 +3164,7 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name,
if (!value || !size)
return -EACCES;
- rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
+ rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
if (rc)
return rc;
@@ -3228,6 +3232,46 @@ static void selinux_file_free_security(struct file *file)
file_free_security(file);
}
+/*
+ * Check whether a task has the ioctl permission and cmd
+ * operation to an inode.
+ */
+static int ioctl_has_perm(const struct cred *cred, struct file *file,
+ u32 requested, u16 cmd)
+{
+ struct common_audit_data ad;
+ struct file_security_struct *fsec = file->f_security;
+ struct inode *inode = file_inode(file);
+ struct inode_security_struct *isec = inode->i_security;
+ struct lsm_ioctlop_audit ioctl;
+ u32 ssid = cred_sid(cred);
+ int rc;
+ u8 driver = cmd >> 8;
+ u8 xperm = cmd & 0xff;
+
+ ad.type = LSM_AUDIT_DATA_IOCTL_OP;
+ ad.u.op = &ioctl;
+ ad.u.op->cmd = cmd;
+ ad.u.op->path = file->f_path;
+
+ if (ssid != fsec->sid) {
+ rc = avc_has_perm(ssid, fsec->sid,
+ SECCLASS_FD,
+ FD__USE,
+ &ad);
+ if (rc)
+ goto out;
+ }
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return 0;
+
+ rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
+ requested, driver, xperm, &ad);
+out:
+ return rc;
+}
+
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
@@ -3270,7 +3314,7 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd,
* to the file's ioctl() function.
*/
default:
- error = file_has_perm(cred, file, FILE__IOCTL);
+ error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
}
return error;
}
@@ -4520,6 +4564,7 @@ static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority
sksec->peer_sid = SECINITSID_UNLABELED;
sksec->sid = SECINITSID_UNLABELED;
+ sksec->sclass = SECCLASS_SOCKET;
selinux_netlbl_sk_security_reset(sksec);
sk->sk_security = sksec;
@@ -4819,7 +4864,7 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb,
return NF_ACCEPT;
}
-static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
+static unsigned int selinux_ipv4_forward(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
@@ -4827,7 +4872,7 @@ static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
+static unsigned int selinux_ipv6_forward(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
@@ -4851,7 +4896,7 @@ static unsigned int selinux_ip_output(struct sk_buff *skb,
if (sk) {
struct sk_security_struct *sksec;
- if (sk->sk_state == TCP_LISTEN)
+ if (sk_listener(sk))
/* if the socket is the listening state then this
* packet is a SYN-ACK packet which means it needs to
* be labeled based on the connection/request_sock and
@@ -4877,7 +4922,7 @@ static unsigned int selinux_ip_output(struct sk_buff *skb,
return NF_ACCEPT;
}
-static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
+static unsigned int selinux_ipv4_output(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
@@ -4958,7 +5003,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
* unfortunately, this means more work, but it is only once per
* connection. */
if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
- !(sk != NULL && sk->sk_state == TCP_LISTEN))
+ !(sk && sk_listener(sk)))
return NF_ACCEPT;
#endif
@@ -4975,7 +5020,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
secmark_perm = PACKET__SEND;
peer_sid = SECINITSID_KERNEL;
}
- } else if (sk->sk_state == TCP_LISTEN) {
+ } else if (sk_listener(sk)) {
/* Locally generated packet but the associated socket is in the
* listening state which means this is a SYN-ACK packet. In
* this particular case the correct security label is assigned
@@ -4986,7 +5031,11 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
* selinux_inet_conn_request(). See also selinux_ip_output()
* for similar problems. */
u32 skb_sid;
- struct sk_security_struct *sksec = sk->sk_security;
+ struct sk_security_struct *sksec;
+
+ if (sk->sk_state == TCP_NEW_SYN_RECV)
+ sk = inet_reqsk(sk)->rsk_listener;
+ sksec = sk->sk_security;
if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
return NF_DROP;
/* At this point, if the returned skb peerlbl is SECSID_NULL
@@ -5052,7 +5101,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
return NF_ACCEPT;
}
-static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
+static unsigned int selinux_ipv4_postroute(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
@@ -5060,7 +5109,7 @@ static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
+static unsigned int selinux_ipv6_postroute(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
@@ -6042,6 +6091,9 @@ static __init int selinux_init(void)
sel_inode_cache = kmem_cache_create("selinux_inode_security",
sizeof(struct inode_security_struct),
0, SLAB_PANIC, NULL);
+ file_security_cache = kmem_cache_create("selinux_file_security",
+ sizeof(struct file_security_struct),
+ 0, SLAB_PANIC, NULL);
avc_init();
security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
@@ -6080,21 +6132,18 @@ security_initcall(selinux_init);
static struct nf_hook_ops selinux_nf_ops[] = {
{
.hook = selinux_ipv4_postroute,
- .owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP_PRI_SELINUX_LAST,
},
{
.hook = selinux_ipv4_forward,
- .owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_FORWARD,
.priority = NF_IP_PRI_SELINUX_FIRST,
},
{
.hook = selinux_ipv4_output,
- .owner = THIS_MODULE,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_SELINUX_FIRST,
@@ -6102,14 +6151,12 @@ static struct nf_hook_ops selinux_nf_ops[] = {
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
{
.hook = selinux_ipv6_postroute,
- .owner = THIS_MODULE,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP6_PRI_SELINUX_LAST,
},
{
.hook = selinux_ipv6_forward,
- .owner = THIS_MODULE,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_FORWARD,
.priority = NF_IP6_PRI_SELINUX_FIRST,