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-rw-r--r--security/smack/smack.h50
-rw-r--r--security/smack/smack_access.c84
-rw-r--r--security/smack/smack_lsm.c649
-rw-r--r--security/smack/smack_netfilter.c26
-rw-r--r--security/smack/smackfs.c97
5 files changed, 566 insertions, 340 deletions
diff --git a/security/smack/smack.h b/security/smack/smack.h
index 62529f382942..e2239be7bd60 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -100,7 +100,12 @@ struct socket_smack {
struct smack_known *smk_out; /* outbound label */
struct smack_known *smk_in; /* inbound label */
struct smack_known *smk_packet; /* TCP peer label */
+ int smk_state; /* netlabel socket states */
};
+#define SMK_NETLBL_UNSET 0
+#define SMK_NETLBL_UNLABELED 1
+#define SMK_NETLBL_LABELED 2
+#define SMK_NETLBL_REQSKB 3
/*
* Inode smack data
@@ -109,9 +114,7 @@ struct inode_smack {
struct smack_known *smk_inode; /* label of the fso */
struct smack_known *smk_task; /* label of the task */
struct smack_known *smk_mmap; /* label of the mmap domain */
- struct mutex smk_lock; /* initialization lock */
int smk_flags; /* smack inode flags */
- struct rcu_head smk_rcu; /* for freeing inode_smack */
};
struct task_smack {
@@ -148,7 +151,6 @@ struct smk_net4addr {
struct smack_known *smk_label; /* label */
};
-#if IS_ENABLED(CONFIG_IPV6)
/*
* An entry in the table identifying IPv6 hosts.
*/
@@ -159,9 +161,7 @@ struct smk_net6addr {
int smk_masks; /* mask size */
struct smack_known *smk_label; /* label */
};
-#endif /* CONFIG_IPV6 */
-#ifdef SMACK_IPV6_PORT_LABELING
/*
* An entry in the table identifying ports.
*/
@@ -174,22 +174,12 @@ struct smk_port_label {
short smk_sock_type; /* Socket type */
short smk_can_reuse;
};
-#endif /* SMACK_IPV6_PORT_LABELING */
struct smack_known_list_elem {
struct list_head list;
struct smack_known *smk_label;
};
-/* Super block security struct flags for mount options */
-#define FSDEFAULT_MNT 0x01
-#define FSFLOOR_MNT 0x02
-#define FSHAT_MNT 0x04
-#define FSROOT_MNT 0x08
-#define FSTRANS_MNT 0x10
-
-#define NUM_SMK_MNT_OPTS 5
-
enum {
Opt_error = -1,
Opt_fsdefault = 0,
@@ -203,19 +193,6 @@ enum {
#define SMACK_CIPSO_OPTION "-CIPSO"
/*
- * How communications on this socket are treated.
- * Usually it's determined by the underlying netlabel code
- * but there are certain cases, including single label hosts
- * and potentially single label interfaces for which the
- * treatment can not be known in advance.
- *
- * The possibility of additional labeling schemes being
- * introduced in the future exists as well.
- */
-#define SMACK_UNLABELED_SOCKET 0
-#define SMACK_CIPSO_SOCKET 1
-
-/*
* CIPSO defaults.
*/
#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */
@@ -311,11 +288,12 @@ struct smack_known *smk_find_entry(const char *);
bool smack_privileged(int cap);
bool smack_privileged_cred(int cap, const struct cred *cred);
void smk_destroy_label_list(struct list_head *list);
+int smack_populate_secattr(struct smack_known *skp);
/*
* Shared data.
*/
-extern int smack_enabled;
+extern int smack_enabled __initdata;
extern int smack_cipso_direct;
extern int smack_cipso_mapped;
extern struct smack_known *smack_net_ambient;
@@ -335,9 +313,7 @@ extern struct smack_known smack_known_web;
extern struct mutex smack_known_lock;
extern struct list_head smack_known_list;
extern struct list_head smk_net4addr_list;
-#if IS_ENABLED(CONFIG_IPV6)
extern struct list_head smk_net6addr_list;
-#endif /* CONFIG_IPV6 */
extern struct mutex smack_onlycap_lock;
extern struct list_head smack_onlycap_list;
@@ -372,6 +348,12 @@ static inline struct smack_known **smack_ipc(const struct kern_ipc_perm *ipc)
return ipc->security + smack_blob_sizes.lbs_ipc;
}
+static inline struct superblock_smack *smack_superblock(
+ const struct super_block *superblock)
+{
+ return superblock->s_security + smack_blob_sizes.lbs_superblock;
+}
+
/*
* Is the directory transmuting?
*/
@@ -398,7 +380,7 @@ static inline struct smack_known *smk_of_task(const struct task_smack *tsp)
return tsp->smk_task;
}
-static inline struct smack_known *smk_of_task_struct(
+static inline struct smack_known *smk_of_task_struct_obj(
const struct task_struct *t)
{
struct smack_known *skp;
@@ -505,10 +487,6 @@ static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a,
struct dentry *d)
{
}
-static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a,
- struct vfsmount *m)
-{
-}
static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a,
struct inode *i)
{
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index 38ac3da4e791..585e5e35710b 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -81,23 +81,22 @@ int log_policy = SMACK_AUDIT_DENIED;
int smk_access_entry(char *subject_label, char *object_label,
struct list_head *rule_list)
{
- int may = -ENOENT;
struct smack_rule *srp;
list_for_each_entry_rcu(srp, rule_list, list) {
if (srp->smk_object->smk_known == object_label &&
srp->smk_subject->smk_known == subject_label) {
- may = srp->smk_access;
- break;
+ int may = srp->smk_access;
+ /*
+ * MAY_WRITE implies MAY_LOCK.
+ */
+ if ((may & MAY_WRITE) == MAY_WRITE)
+ may |= MAY_LOCK;
+ return may;
}
}
- /*
- * MAY_WRITE implies MAY_LOCK.
- */
- if ((may & MAY_WRITE) == MAY_WRITE)
- may |= MAY_LOCK;
- return may;
+ return -ENOENT;
}
/**
@@ -332,7 +331,7 @@ static void smack_log_callback(struct audit_buffer *ab, void *a)
* @object_label : smack label of the object being accessed
* @request: requested permissions
* @result: result from smk_access
- * @a: auxiliary audit data
+ * @ad: auxiliary audit data
*
* Audit the granting or denial of permissions in accordance
* with the policy.
@@ -396,6 +395,7 @@ struct hlist_head smack_known_hash[SMACK_HASH_SLOTS];
/**
* smk_insert_entry - insert a smack label into a hash map,
+ * @skp: smack label
*
* this function must be called under smack_known_lock
*/
@@ -465,19 +465,18 @@ char *smk_parse_smack(const char *string, int len)
if (i == 0 || i >= SMK_LONGLABEL)
return ERR_PTR(-EINVAL);
- smack = kzalloc(i + 1, GFP_NOFS);
- if (smack == NULL)
+ smack = kstrndup(string, i, GFP_NOFS);
+ if (!smack)
return ERR_PTR(-ENOMEM);
-
- strncpy(smack, string, i);
-
return smack;
}
/**
* smk_netlbl_mls - convert a catset to netlabel mls categories
+ * @level: MLS sensitivity level
* @catset: the Smack categories
* @sap: where to put the netlabel categories
+ * @len: number of bytes for the levels in a CIPSO IP option
*
* Allocates and fills attr.mls
* Returns 0 on success, error code on failure.
@@ -511,6 +510,42 @@ int smk_netlbl_mls(int level, char *catset, struct netlbl_lsm_secattr *sap,
}
/**
+ * smack_populate_secattr - fill in the smack_known netlabel information
+ * @skp: pointer to the structure to fill
+ *
+ * Populate the netlabel secattr structure for a Smack label.
+ *
+ * Returns 0 unless creating the category mapping fails
+ */
+int smack_populate_secattr(struct smack_known *skp)
+{
+ int slen;
+
+ skp->smk_netlabel.attr.secid = skp->smk_secid;
+ skp->smk_netlabel.domain = skp->smk_known;
+ skp->smk_netlabel.cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
+ if (skp->smk_netlabel.cache != NULL) {
+ skp->smk_netlabel.flags |= NETLBL_SECATTR_CACHE;
+ skp->smk_netlabel.cache->free = NULL;
+ skp->smk_netlabel.cache->data = skp;
+ }
+ skp->smk_netlabel.flags |= NETLBL_SECATTR_SECID |
+ NETLBL_SECATTR_MLS_LVL |
+ NETLBL_SECATTR_DOMAIN;
+ /*
+ * If direct labeling works use it.
+ * Otherwise use mapped labeling.
+ */
+ slen = strlen(skp->smk_known);
+ if (slen < SMK_CIPSOLEN)
+ return smk_netlbl_mls(smack_cipso_direct, skp->smk_known,
+ &skp->smk_netlabel, slen);
+
+ return smk_netlbl_mls(smack_cipso_mapped, (char *)&skp->smk_secid,
+ &skp->smk_netlabel, sizeof(skp->smk_secid));
+}
+
+/**
* smk_import_entry - import a label, return the list entry
* @string: a text string that might be a Smack label
* @len: the maximum size, or zero if it is NULL terminated.
@@ -523,7 +558,6 @@ struct smack_known *smk_import_entry(const char *string, int len)
{
struct smack_known *skp;
char *smack;
- int slen;
int rc;
smack = smk_parse_smack(string, len);
@@ -544,21 +578,8 @@ struct smack_known *smk_import_entry(const char *string, int len)
skp->smk_known = smack;
skp->smk_secid = smack_next_secid++;
- skp->smk_netlabel.domain = skp->smk_known;
- skp->smk_netlabel.flags =
- NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
- /*
- * If direct labeling works use it.
- * Otherwise use mapped labeling.
- */
- slen = strlen(smack);
- if (slen < SMK_CIPSOLEN)
- rc = smk_netlbl_mls(smack_cipso_direct, skp->smk_known,
- &skp->smk_netlabel, slen);
- else
- rc = smk_netlbl_mls(smack_cipso_mapped, (char *)&skp->smk_secid,
- &skp->smk_netlabel, sizeof(skp->smk_secid));
+ rc = smack_populate_secattr(skp);
if (rc >= 0) {
INIT_LIST_HEAD(&skp->smk_rules);
mutex_init(&skp->smk_rules_lock);
@@ -569,9 +590,6 @@ struct smack_known *smk_import_entry(const char *string, int len)
smk_insert_entry(skp);
goto unlockout;
}
- /*
- * smk_netlbl_mls failed.
- */
kfree(skp);
skp = ERR_PTR(rc);
freeout:
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 8c61d175e195..b6306d71c908 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -41,6 +41,8 @@
#include <linux/parser.h>
#include <linux/fs_context.h>
#include <linux/fs_parser.h>
+#include <linux/watch_queue.h>
+#include <linux/io_uring.h>
#include "smack.h"
#define TRANS_TRUE "TRUE"
@@ -51,12 +53,11 @@
#define SMK_SENDING 2
#ifdef SMACK_IPV6_PORT_LABELING
-DEFINE_MUTEX(smack_ipv6_lock);
+static DEFINE_MUTEX(smack_ipv6_lock);
static LIST_HEAD(smk_ipv6_port_list);
#endif
-static struct kmem_cache *smack_inode_cache;
struct kmem_cache *smack_rule_cache;
-int smack_enabled;
+int smack_enabled __initdata;
#define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
static struct {
@@ -161,7 +162,7 @@ static int smk_bu_current(char *note, struct smack_known *oskp,
static int smk_bu_task(struct task_struct *otp, int mode, int rc)
{
struct task_smack *tsp = smack_cred(current_cred());
- struct smack_known *smk_task = smk_of_task_struct(otp);
+ struct smack_known *smk_task = smk_of_task_struct_obj(otp);
char acc[SMK_NUM_ACCESS_TYPE + 1];
if (rc <= 0)
@@ -316,7 +317,6 @@ static void init_inode_smack(struct inode *inode, struct smack_known *skp)
isp->smk_inode = skp;
isp->smk_flags = 0;
- mutex_init(&isp->smk_lock);
}
/**
@@ -392,7 +392,7 @@ static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
/**
* smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
- * @mode - input mode in form of PTRACE_MODE_*
+ * @mode: input mode in form of PTRACE_MODE_*
*
* Returns a converted MAY_* mode usable by smack rules
*/
@@ -482,7 +482,7 @@ static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
{
struct smack_known *skp;
- skp = smk_of_task_struct(ctp);
+ skp = smk_of_task_struct_obj(ctp);
return smk_ptrace_rule_check(current, skp, mode, __func__);
}
@@ -497,13 +497,11 @@ static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
*/
static int smack_ptrace_traceme(struct task_struct *ptp)
{
- int rc;
struct smack_known *skp;
skp = smk_of_task(smack_cred(current_cred()));
- rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
- return rc;
+ return smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
}
/**
@@ -538,12 +536,7 @@ static int smack_syslog(int typefrom_file)
*/
static int smack_sb_alloc_security(struct super_block *sb)
{
- struct superblock_smack *sbsp;
-
- sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
-
- if (sbsp == NULL)
- return -ENOMEM;
+ struct superblock_smack *sbsp = smack_superblock(sb);
sbsp->smk_root = &smack_known_floor;
sbsp->smk_default = &smack_known_floor;
@@ -552,22 +545,10 @@ static int smack_sb_alloc_security(struct super_block *sb)
/*
* SMK_SB_INITIALIZED will be zero from kzalloc.
*/
- sb->s_security = sbsp;
return 0;
}
-/**
- * smack_sb_free_security - free a superblock blob
- * @sb: the superblock getting the blob
- *
- */
-static void smack_sb_free_security(struct super_block *sb)
-{
- kfree(sb->s_security);
- sb->s_security = NULL;
-}
-
struct smack_mnt_opts {
const char *fsdefault, *fsfloor, *fshat, *fsroot, *fstransmute;
};
@@ -775,7 +756,7 @@ static int smack_set_mnt_opts(struct super_block *sb,
{
struct dentry *root = sb->s_root;
struct inode *inode = d_backing_inode(root);
- struct superblock_smack *sp = sb->s_security;
+ struct superblock_smack *sp = smack_superblock(sb);
struct inode_smack *isp;
struct smack_known *skp;
struct smack_mnt_opts *opts = mnt_opts;
@@ -784,13 +765,6 @@ static int smack_set_mnt_opts(struct super_block *sb,
if (sp->smk_flags & SMK_SB_INITIALIZED)
return 0;
- if (inode->i_security == NULL) {
- int rc = lsm_inode_alloc(inode);
-
- if (rc)
- return rc;
- }
-
if (!smack_privileged(CAP_MAC_ADMIN)) {
/*
* Unprivileged mounts don't get to specify Smack values.
@@ -874,7 +848,7 @@ static int smack_set_mnt_opts(struct super_block *sb,
*/
static int smack_sb_statfs(struct dentry *dentry)
{
- struct superblock_smack *sbp = dentry->d_sb->s_security;
+ struct superblock_smack *sbp = smack_superblock(dentry->d_sb);
int rc;
struct smk_audit_info ad;
@@ -891,12 +865,12 @@ static int smack_sb_statfs(struct dentry *dentry)
*/
/**
- * smack_bprm_set_creds - set creds for exec
+ * smack_bprm_creds_for_exec - Update bprm->cred if needed for exec
* @bprm: the exec information
*
* Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
*/
-static int smack_bprm_set_creds(struct linux_binprm *bprm)
+static int smack_bprm_creds_for_exec(struct linux_binprm *bprm)
{
struct inode *inode = file_inode(bprm->file);
struct task_smack *bsp = smack_cred(bprm->cred);
@@ -904,14 +878,11 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm)
struct superblock_smack *sbsp;
int rc;
- if (bprm->called_set_creds)
- return 0;
-
isp = smack_inode(inode);
if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
return 0;
- sbsp = inode->i_sb->s_security;
+ sbsp = smack_superblock(inode->i_sb);
if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
isp->smk_task != sbsp->smk_root)
return 0;
@@ -1163,7 +1134,7 @@ static int smack_inode_rename(struct inode *old_inode,
*/
static int smack_inode_permission(struct inode *inode, int mask)
{
- struct superblock_smack *sbsp = inode->i_sb->s_security;
+ struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
struct smk_audit_info ad;
int no_block = mask & MAY_NOT_BLOCK;
int rc;
@@ -1236,6 +1207,7 @@ static int smack_inode_getattr(const struct path *path)
/**
* smack_inode_setxattr - Smack check for setting xattrs
+ * @mnt_userns: active user namespace
* @dentry: the object
* @name: name of the attribute
* @value: value of the attribute
@@ -1246,7 +1218,8 @@ static int smack_inode_getattr(const struct path *path)
*
* Returns 0 if access is permitted, an error code otherwise
*/
-static int smack_inode_setxattr(struct dentry *dentry, const char *name,
+static int smack_inode_setxattr(struct user_namespace *mnt_userns,
+ struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
struct smk_audit_info ad;
@@ -1361,6 +1334,7 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name)
/**
* smack_inode_removexattr - Smack check on removexattr
+ * @mnt_userns: active user namespace
* @dentry: the object
* @name: name of the attribute
*
@@ -1368,7 +1342,8 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name)
*
* Returns 0 if access is permitted, an error code otherwise
*/
-static int smack_inode_removexattr(struct dentry *dentry, const char *name)
+static int smack_inode_removexattr(struct user_namespace *mnt_userns,
+ struct dentry *dentry, const char *name)
{
struct inode_smack *isp;
struct smk_audit_info ad;
@@ -1383,7 +1358,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
if (!smack_privileged(CAP_MAC_ADMIN))
rc = -EPERM;
} else
- rc = cap_inode_removexattr(dentry, name);
+ rc = cap_inode_removexattr(mnt_userns, dentry, name);
if (rc != 0)
return rc;
@@ -1404,7 +1379,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
*/
if (strcmp(name, XATTR_NAME_SMACK) == 0) {
struct super_block *sbp = dentry->d_sb;
- struct superblock_smack *sbsp = sbp->s_security;
+ struct superblock_smack *sbsp = smack_superblock(sbp);
isp->smk_inode = sbsp->smk_default;
} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
@@ -1419,6 +1394,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
/**
* smack_inode_getsecurity - get smack xattrs
+ * @mnt_userns: active user namespace
* @inode: the object
* @name: attribute name
* @buffer: where to put the result
@@ -1426,9 +1402,9 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
*
* Returns the size of the attribute or an error code
*/
-static int smack_inode_getsecurity(struct inode *inode,
- const char *name, void **buffer,
- bool alloc)
+static int smack_inode_getsecurity(struct user_namespace *mnt_userns,
+ struct inode *inode, const char *name,
+ void **buffer, bool alloc)
{
struct socket_smack *ssp;
struct socket *sock;
@@ -1640,13 +1616,14 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd,
}
/**
- * smack_mmap_file :
- * Check permissions for a mmap operation. The @file may be NULL, e.g.
- * if mapping anonymous memory.
- * @file contains the file structure for file to map (may be NULL).
- * @reqprot contains the protection requested by the application.
- * @prot contains the protection that will be applied by the kernel.
- * @flags contains the operational flags.
+ * smack_mmap_file - Check permissions for a mmap operation.
+ * @file: contains the file structure for file to map (may be NULL).
+ * @reqprot: contains the protection requested by the application.
+ * @prot: contains the protection that will be applied by the kernel.
+ * @flags: contains the operational flags.
+ *
+ * The @file may be NULL, e.g. if mapping anonymous memory.
+ *
* Return 0 if permission is granted.
*/
static int smack_mmap_file(struct file *file,
@@ -1674,7 +1651,7 @@ static int smack_mmap_file(struct file *file,
isp = smack_inode(file_inode(file));
if (isp->smk_mmap == NULL)
return 0;
- sbsp = file_inode(file)->i_sb->s_security;
+ sbsp = smack_superblock(file_inode(file)->i_sb);
if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
isp->smk_mmap != sbsp->smk_root)
return -EACCES;
@@ -2037,7 +2014,7 @@ static int smk_curacc_on_task(struct task_struct *p, int access,
const char *caller)
{
struct smk_audit_info ad;
- struct smack_known *skp = smk_of_task_struct(p);
+ struct smack_known *skp = smk_of_task_struct_obj(p);
int rc;
smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
@@ -2082,15 +2059,28 @@ static int smack_task_getsid(struct task_struct *p)
}
/**
- * smack_task_getsecid - get the secid of the task
- * @p: the object task
+ * smack_current_getsecid_subj - get the subjective secid of the current task
* @secid: where to put the result
*
- * Sets the secid to contain a u32 version of the smack label.
+ * Sets the secid to contain a u32 version of the task's subjective smack label.
*/
-static void smack_task_getsecid(struct task_struct *p, u32 *secid)
+static void smack_current_getsecid_subj(u32 *secid)
{
- struct smack_known *skp = smk_of_task_struct(p);
+ struct smack_known *skp = smk_of_current();
+
+ *secid = skp->smk_secid;
+}
+
+/**
+ * smack_task_getsecid_obj - get the objective secid of the task
+ * @p: the task
+ * @secid: where to put the result
+ *
+ * Sets the secid to contain a u32 version of the task's objective smack label.
+ */
+static void smack_task_getsecid_obj(struct task_struct *p, u32 *secid)
+{
+ struct smack_known *skp = smk_of_task_struct_obj(p);
*secid = skp->smk_secid;
}
@@ -2178,7 +2168,7 @@ static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
{
struct smk_audit_info ad;
struct smack_known *skp;
- struct smack_known *tkp = smk_of_task_struct(p);
+ struct smack_known *tkp = smk_of_task_struct_obj(p);
int rc;
if (!sig)
@@ -2216,7 +2206,7 @@ static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
{
struct inode_smack *isp = smack_inode(inode);
- struct smack_known *skp = smk_of_task_struct(p);
+ struct smack_known *skp = smk_of_task_struct_obj(p);
isp->smk_inode = skp;
isp->smk_flags |= SMK_INODE_INSTANT;
@@ -2288,6 +2278,21 @@ static void smack_sk_free_security(struct sock *sk)
}
/**
+ * smack_sk_clone_security - Copy security context
+ * @sk: the old socket
+ * @newsk: the new socket
+ *
+ * Copy the security context of the old socket pointer to the cloned
+ */
+static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk)
+{
+ struct socket_smack *ssp_old = sk->sk_security;
+ struct socket_smack *ssp_new = newsk->sk_security;
+
+ *ssp_new = *ssp_old;
+}
+
+/**
* smack_ipv4host_label - check host based restrictions
* @sip: the object end
*
@@ -2320,7 +2325,6 @@ static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
return NULL;
}
-#if IS_ENABLED(CONFIG_IPV6)
/*
* smk_ipv6_localhost - Check for local ipv6 host address
* @sip: the address
@@ -2388,41 +2392,33 @@ static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
return NULL;
}
-#endif /* CONFIG_IPV6 */
/**
- * smack_netlabel - Set the secattr on a socket
+ * smack_netlbl_add - Set the secattr on a socket
* @sk: the socket
- * @labeled: socket label scheme
*
- * Convert the outbound smack value (smk_out) to a
- * secattr and attach it to the socket.
+ * Attach the outbound smack value (smk_out) to the socket.
*
* Returns 0 on success or an error code
*/
-static int smack_netlabel(struct sock *sk, int labeled)
+static int smack_netlbl_add(struct sock *sk)
{
- struct smack_known *skp;
struct socket_smack *ssp = sk->sk_security;
- int rc = 0;
+ struct smack_known *skp = ssp->smk_out;
+ int rc;
- /*
- * Usually the netlabel code will handle changing the
- * packet labeling based on the label.
- * The case of a single label host is different, because
- * a single label host should never get a labeled packet
- * even though the label is usually associated with a packet
- * label.
- */
local_bh_disable();
bh_lock_sock_nested(sk);
- if (ssp->smk_out == smack_net_ambient ||
- labeled == SMACK_UNLABELED_SOCKET)
- netlbl_sock_delattr(sk);
- else {
- skp = ssp->smk_out;
- rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
+ rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
+ switch (rc) {
+ case 0:
+ ssp->smk_state = SMK_NETLBL_LABELED;
+ break;
+ case -EDESTADDRREQ:
+ ssp->smk_state = SMK_NETLBL_REQSKB;
+ rc = 0;
+ break;
}
bh_unlock_sock(sk);
@@ -2432,7 +2428,31 @@ static int smack_netlabel(struct sock *sk, int labeled)
}
/**
- * smack_netlbel_send - Set the secattr on a socket and perform access checks
+ * smack_netlbl_delete - Remove the secattr from a socket
+ * @sk: the socket
+ *
+ * Remove the outbound smack value from a socket
+ */
+static void smack_netlbl_delete(struct sock *sk)
+{
+ struct socket_smack *ssp = sk->sk_security;
+
+ /*
+ * Take the label off the socket if one is set.
+ */
+ if (ssp->smk_state != SMK_NETLBL_LABELED)
+ return;
+
+ local_bh_disable();
+ bh_lock_sock_nested(sk);
+ netlbl_sock_delattr(sk);
+ bh_unlock_sock(sk);
+ local_bh_enable();
+ ssp->smk_state = SMK_NETLBL_UNLABELED;
+}
+
+/**
+ * smk_ipv4_check - Perform IPv4 host access checks
* @sk: the socket
* @sap: the destination address
*
@@ -2442,11 +2462,10 @@ static int smack_netlabel(struct sock *sk, int labeled)
* Returns 0 on success or an error code.
*
*/
-static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
+static int smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap)
{
struct smack_known *skp;
- int rc;
- int sk_lbl;
+ int rc = 0;
struct smack_known *hkp;
struct socket_smack *ssp = sk->sk_security;
struct smk_audit_info ad;
@@ -2462,22 +2481,20 @@ static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
ad.a.u.net->dport = sap->sin_port;
ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
#endif
- sk_lbl = SMACK_UNLABELED_SOCKET;
skp = ssp->smk_out;
rc = smk_access(skp, hkp, MAY_WRITE, &ad);
rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
- } else {
- sk_lbl = SMACK_CIPSO_SOCKET;
- rc = 0;
+ /*
+ * Clear the socket netlabel if it's set.
+ */
+ if (!rc)
+ smack_netlbl_delete(sk);
}
rcu_read_unlock();
- if (rc != 0)
- return rc;
- return smack_netlabel(sk, sk_lbl);
+ return rc;
}
-#if IS_ENABLED(CONFIG_IPV6)
/**
* smk_ipv6_check - check Smack access
* @subject: subject Smack label
@@ -2500,7 +2517,7 @@ static int smk_ipv6_check(struct smack_known *subject,
#ifdef CONFIG_AUDIT
smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
ad.a.u.net->family = PF_INET6;
- ad.a.u.net->dport = ntohs(address->sin6_port);
+ ad.a.u.net->dport = address->sin6_port;
if (act == SMK_RECEIVING)
ad.a.u.net->v6info.saddr = address->sin6_addr;
else
@@ -2510,7 +2527,6 @@ static int smk_ipv6_check(struct smack_known *subject,
rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
return rc;
}
-#endif /* CONFIG_IPV6 */
#ifdef SMACK_IPV6_PORT_LABELING
/**
@@ -2661,7 +2677,7 @@ static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
return smk_ipv6_check(skp, object, address, act);
}
-#endif /* SMACK_IPV6_PORT_LABELING */
+#endif
/**
* smack_inode_setsecurity - set smack xattrs
@@ -2713,7 +2729,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name,
else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
ssp->smk_out = skp;
if (sock->sk->sk_family == PF_INET) {
- rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
+ rc = smack_netlbl_add(sock->sk);
if (rc != 0)
printk(KERN_WARNING
"Smack: \"%s\" netlbl error %d.\n",
@@ -2764,7 +2780,7 @@ static int smack_socket_post_create(struct socket *sock, int family,
/*
* Set the outbound netlbl.
*/
- return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
+ return smack_netlbl_add(sock->sk);
}
/**
@@ -2836,29 +2852,27 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
return 0;
if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
-#ifdef SMACK_IPV6_SECMARK_LABELING
- struct smack_known *rsp;
-#endif
+ struct smack_known *rsp = NULL;
if (addrlen < SIN6_LEN_RFC2133)
return 0;
-#ifdef SMACK_IPV6_SECMARK_LABELING
- rsp = smack_ipv6host_label(sip);
+ if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
+ rsp = smack_ipv6host_label(sip);
if (rsp != NULL) {
struct socket_smack *ssp = sock->sk->sk_security;
rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
SMK_CONNECTING);
}
-#endif
#ifdef SMACK_IPV6_PORT_LABELING
rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
#endif
+
return rc;
}
if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
return 0;
- rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
+ rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap);
return rc;
}
@@ -3050,7 +3064,7 @@ static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
}
/**
- * smack_sem_shmctl - Smack access check for sem
+ * smack_sem_semctl - Smack access check for sem
* @isp: the object
* @cmd: what it wants to do
*
@@ -3196,7 +3210,7 @@ static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg
}
/**
- * smack_msg_queue_msgsnd - Smack access check for msg_queue
+ * smack_msg_queue_msgrcv - Smack access check for msg_queue
* @isp: the object
* @msg: unused
* @target: unused
@@ -3205,8 +3219,10 @@ static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg
*
* Returns 0 if current has read and write access, error code otherwise
*/
-static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp, struct msg_msg *msg,
- struct task_struct *target, long type, int mode)
+static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp,
+ struct msg_msg *msg,
+ struct task_struct *target, long type,
+ int mode)
{
return smk_curacc_msq(isp, MAY_READWRITE);
}
@@ -3273,16 +3289,15 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
isp = smack_inode(inode);
- mutex_lock(&isp->smk_lock);
/*
* If the inode is already instantiated
* take the quick way out
*/
if (isp->smk_flags & SMK_INODE_INSTANT)
- goto unlockandout;
+ return;
sbp = inode->i_sb;
- sbsp = sbp->s_security;
+ sbsp = smack_superblock(sbp);
/*
* We're going to use the superblock default label
* if there's no label on the file.
@@ -3330,7 +3345,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
break;
}
isp->smk_flags |= SMK_INODE_INSTANT;
- goto unlockandout;
+ return;
}
/*
@@ -3379,7 +3394,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
* to set mount options simulate setting the
* superblock default.
*/
- /* Fall through */
+ fallthrough;
default:
/*
* This isn't an understood special case.
@@ -3424,7 +3439,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
*/
if (isp->smk_flags & SMK_INODE_CHANGED) {
isp->smk_flags &= ~SMK_INODE_CHANGED;
- rc = __vfs_setxattr(dp, inode,
+ rc = __vfs_setxattr(&init_user_ns, dp, inode,
XATTR_NAME_SMACKTRANSMUTE,
TRANS_TRUE, TRANS_TRUE_SIZE,
0);
@@ -3465,8 +3480,6 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
-unlockandout:
- mutex_unlock(&isp->smk_lock);
return;
}
@@ -3480,9 +3493,9 @@ unlockandout:
*
* Returns the length of the smack label or an error code
*/
-static int smack_getprocattr(struct task_struct *p, char *name, char **value)
+static int smack_getprocattr(struct task_struct *p, const char *name, char **value)
{
- struct smack_known *skp = smk_of_task_struct(p);
+ struct smack_known *skp = smk_of_task_struct_obj(p);
char *cp;
int slen;
@@ -3679,7 +3692,7 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
sip->sin_family != AF_INET)
return -EINVAL;
- rc = smack_netlabel_send(sock->sk, sip);
+ rc = smk_ipv4_check(sock->sk, sip);
break;
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
@@ -3716,6 +3729,18 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
int acat;
int kcat;
+ /*
+ * Netlabel found it in the cache.
+ */
+ if ((sap->flags & NETLBL_SECATTR_CACHE) != 0)
+ return (struct smack_known *)sap->cache->data;
+
+ if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
+ /*
+ * Looks like a fallback, which gives us a secid.
+ */
+ return smack_from_secid(sap->attr.secid);
+
if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
/*
* Looks like a CIPSO packet.
@@ -3763,11 +3788,6 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
return &smack_known_web;
return &smack_known_star;
}
- if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
- /*
- * Looks like a fallback, which gives us a secid.
- */
- return smack_from_secid(sap->attr.secid);
/*
* Without guidance regarding the smack value
* for the packet fall back on the network
@@ -3827,6 +3847,61 @@ static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
#endif /* CONFIG_IPV6 */
/**
+ * smack_from_skb - Smack data from the secmark in an skb
+ * @skb: packet
+ *
+ * Returns smack_known of the secmark or NULL if that won't work.
+ */
+#ifdef CONFIG_NETWORK_SECMARK
+static struct smack_known *smack_from_skb(struct sk_buff *skb)
+{
+ if (skb == NULL || skb->secmark == 0)
+ return NULL;
+
+ return smack_from_secid(skb->secmark);
+}
+#else
+static inline struct smack_known *smack_from_skb(struct sk_buff *skb)
+{
+ return NULL;
+}
+#endif
+
+/**
+ * smack_from_netlbl - Smack data from the IP options in an skb
+ * @sk: socket data came in on
+ * @family: address family
+ * @skb: packet
+ *
+ * Find the Smack label in the IP options. If it hasn't been
+ * added to the netlabel cache, add it here.
+ *
+ * Returns smack_known of the IP options or NULL if that won't work.
+ */
+static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family,
+ struct sk_buff *skb)
+{
+ struct netlbl_lsm_secattr secattr;
+ struct socket_smack *ssp = NULL;
+ struct smack_known *skp = NULL;
+
+ netlbl_secattr_init(&secattr);
+
+ if (sk)
+ ssp = sk->sk_security;
+
+ if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) {
+ skp = smack_from_secattr(&secattr, ssp);
+ if (secattr.flags & NETLBL_SECATTR_CACHEABLE)
+ netlbl_cache_add(skb, family, &skp->smk_netlabel);
+ }
+
+ netlbl_secattr_destroy(&secattr);
+
+ return skp;
+}
+
+/**
* smack_socket_sock_rcv_skb - Smack packet delivery access check
* @sk: socket
* @skb: packet
@@ -3835,7 +3910,6 @@ static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
*/
static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
- struct netlbl_lsm_secattr secattr;
struct socket_smack *ssp = sk->sk_security;
struct smack_known *skp = NULL;
int rc = 0;
@@ -3854,33 +3928,18 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
switch (family) {
case PF_INET:
-#ifdef CONFIG_SECURITY_SMACK_NETFILTER
/*
* If there is a secmark use it rather than the CIPSO label.
* If there is no secmark fall back to CIPSO.
* The secmark is assumed to reflect policy better.
*/
- if (skb && skb->secmark != 0) {
- skp = smack_from_secid(skb->secmark);
- goto access_check;
+ skp = smack_from_skb(skb);
+ if (skp == NULL) {
+ skp = smack_from_netlbl(sk, family, skb);
+ if (skp == NULL)
+ skp = smack_net_ambient;
}
-#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
- /*
- * Translate what netlabel gave us.
- */
- netlbl_secattr_init(&secattr);
-
- rc = netlbl_skbuff_getattr(skb, family, &secattr);
- if (rc == 0)
- skp = smack_from_secattr(&secattr, ssp);
- else
- skp = smack_net_ambient;
- netlbl_secattr_destroy(&secattr);
-
-#ifdef CONFIG_SECURITY_SMACK_NETFILTER
-access_check:
-#endif
#ifdef CONFIG_AUDIT
smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
ad.a.u.net->family = family;
@@ -3906,16 +3965,14 @@ access_check:
proto != IPPROTO_TCP && proto != IPPROTO_DCCP)
break;
#ifdef SMACK_IPV6_SECMARK_LABELING
- if (skb && skb->secmark != 0)
- skp = smack_from_secid(skb->secmark);
- else if (smk_ipv6_localhost(&sadd))
- break;
- else
+ skp = smack_from_skb(skb);
+ if (skp == NULL) {
+ if (smk_ipv6_localhost(&sadd))
+ break;
skp = smack_ipv6host_label(&sadd);
- if (skp == NULL)
- skp = smack_net_ambient;
- if (skb == NULL)
- break;
+ if (skp == NULL)
+ skp = smack_net_ambient;
+ }
#ifdef CONFIG_AUDIT
smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
ad.a.u.net->family = family;
@@ -3987,12 +4044,11 @@ static int smack_socket_getpeersec_dgram(struct socket *sock,
struct sk_buff *skb, u32 *secid)
{
- struct netlbl_lsm_secattr secattr;
struct socket_smack *ssp = NULL;
struct smack_known *skp;
+ struct sock *sk = NULL;
int family = PF_UNSPEC;
u32 s = 0; /* 0 is the invalid secid */
- int rc;
if (skb != NULL) {
if (skb->protocol == htons(ETH_P_IP))
@@ -4011,27 +4067,25 @@ static int smack_socket_getpeersec_dgram(struct socket *sock,
s = ssp->smk_out->smk_secid;
break;
case PF_INET:
-#ifdef CONFIG_SECURITY_SMACK_NETFILTER
- s = skb->secmark;
- if (s != 0)
+ skp = smack_from_skb(skb);
+ if (skp) {
+ s = skp->smk_secid;
break;
-#endif
+ }
/*
* Translate what netlabel gave us.
*/
- if (sock != NULL && sock->sk != NULL)
- ssp = sock->sk->sk_security;
- netlbl_secattr_init(&secattr);
- rc = netlbl_skbuff_getattr(skb, family, &secattr);
- if (rc == 0) {
- skp = smack_from_secattr(&secattr, ssp);
+ if (sock != NULL)
+ sk = sock->sk;
+ skp = smack_from_netlbl(sk, family, skb);
+ if (skp != NULL)
s = skp->smk_secid;
- }
- netlbl_secattr_destroy(&secattr);
break;
case PF_INET6:
#ifdef SMACK_IPV6_SECMARK_LABELING
- s = skb->secmark;
+ skp = smack_from_skb(skb);
+ if (skp)
+ s = skp->smk_secid;
#endif
break;
}
@@ -4073,13 +4127,12 @@ static void smack_sock_graft(struct sock *sk, struct socket *parent)
* Returns 0 if a task with the packet label could write to
* the socket, otherwise an error code
*/
-static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
+static int smack_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
struct request_sock *req)
{
u16 family = sk->sk_family;
struct smack_known *skp;
struct socket_smack *ssp = sk->sk_security;
- struct netlbl_lsm_secattr secattr;
struct sockaddr_in addr;
struct iphdr *hdr;
struct smack_known *hskp;
@@ -4103,29 +4156,17 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
}
#endif /* CONFIG_IPV6 */
-#ifdef CONFIG_SECURITY_SMACK_NETFILTER
/*
* If there is a secmark use it rather than the CIPSO label.
* If there is no secmark fall back to CIPSO.
* The secmark is assumed to reflect policy better.
*/
- if (skb && skb->secmark != 0) {
- skp = smack_from_secid(skb->secmark);
- goto access_check;
+ skp = smack_from_skb(skb);
+ if (skp == NULL) {
+ skp = smack_from_netlbl(sk, family, skb);
+ if (skp == NULL)
+ skp = &smack_known_huh;
}
-#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
-
- netlbl_secattr_init(&secattr);
- rc = netlbl_skbuff_getattr(skb, family, &secattr);
- if (rc == 0)
- skp = smack_from_secattr(&secattr, ssp);
- else
- skp = &smack_known_huh;
- netlbl_secattr_destroy(&secattr);
-
-#ifdef CONFIG_SECURITY_SMACK_NETFILTER
-access_check:
-#endif
#ifdef CONFIG_AUDIT
smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
@@ -4230,13 +4271,14 @@ static void smack_key_free(struct key *key)
* smack_key_permission - Smack access on a key
* @key_ref: gets to the object
* @cred: the credentials to use
- * @perm: requested key permissions
+ * @need_perm: requested key permission
*
* Return 0 if the task has read and write to the object,
* an error code otherwise
*/
static int smack_key_permission(key_ref_t key_ref,
- const struct cred *cred, unsigned perm)
+ const struct cred *cred,
+ enum key_need_perm need_perm)
{
struct key *keyp;
struct smk_audit_info ad;
@@ -4247,8 +4289,26 @@ static int smack_key_permission(key_ref_t key_ref,
/*
* Validate requested permissions
*/
- if (perm & ~KEY_NEED_ALL)
+ switch (need_perm) {
+ case KEY_NEED_READ:
+ case KEY_NEED_SEARCH:
+ case KEY_NEED_VIEW:
+ request |= MAY_READ;
+ break;
+ case KEY_NEED_WRITE:
+ case KEY_NEED_LINK:
+ case KEY_NEED_SETATTR:
+ request |= MAY_WRITE;
+ break;
+ case KEY_NEED_UNSPECIFIED:
+ case KEY_NEED_UNLINK:
+ case KEY_SYSADMIN_OVERRIDE:
+ case KEY_AUTHTOKEN_OVERRIDE:
+ case KEY_DEFER_PERM_CHECK:
+ return 0;
+ default:
return -EINVAL;
+ }
keyp = key_ref_to_ptr(key_ref);
if (keyp == NULL)
@@ -4265,7 +4325,7 @@ static int smack_key_permission(key_ref_t key_ref,
if (tkp == NULL)
return -EACCES;
- if (smack_privileged_cred(CAP_MAC_OVERRIDE, cred))
+ if (smack_privileged(CAP_MAC_OVERRIDE))
return 0;
#ifdef CONFIG_AUDIT
@@ -4273,10 +4333,6 @@ static int smack_key_permission(key_ref_t key_ref,
ad.a.u.key_struct.key = keyp->serial;
ad.a.u.key_struct.key_desc = keyp->description;
#endif
- if (perm & (KEY_NEED_READ | KEY_NEED_SEARCH | KEY_NEED_VIEW))
- request |= MAY_READ;
- if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
- request |= MAY_WRITE;
rc = smk_access(tkp, keyp->security, request, &ad);
rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
return rc;
@@ -4311,8 +4367,81 @@ static int smack_key_getsecurity(struct key *key, char **_buffer)
return length;
}
+
+#ifdef CONFIG_KEY_NOTIFICATIONS
+/**
+ * smack_watch_key - Smack access to watch a key for notifications.
+ * @key: The key to be watched
+ *
+ * Return 0 if the @watch->cred has permission to read from the key object and
+ * an error otherwise.
+ */
+static int smack_watch_key(struct key *key)
+{
+ struct smk_audit_info ad;
+ struct smack_known *tkp = smk_of_current();
+ int rc;
+
+ if (key == NULL)
+ return -EINVAL;
+ /*
+ * If the key hasn't been initialized give it access so that
+ * it may do so.
+ */
+ if (key->security == NULL)
+ return 0;
+ /*
+ * This should not occur
+ */
+ if (tkp == NULL)
+ return -EACCES;
+
+ if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
+ return 0;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
+ ad.a.u.key_struct.key = key->serial;
+ ad.a.u.key_struct.key_desc = key->description;
+#endif
+ rc = smk_access(tkp, key->security, MAY_READ, &ad);
+ rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc);
+ return rc;
+}
+#endif /* CONFIG_KEY_NOTIFICATIONS */
#endif /* CONFIG_KEYS */
+#ifdef CONFIG_WATCH_QUEUE
+/**
+ * smack_post_notification - Smack access to post a notification to a queue
+ * @w_cred: The credentials of the watcher.
+ * @cred: The credentials of the event source (may be NULL).
+ * @n: The notification message to be posted.
+ */
+static int smack_post_notification(const struct cred *w_cred,
+ const struct cred *cred,
+ struct watch_notification *n)
+{
+ struct smk_audit_info ad;
+ struct smack_known *subj, *obj;
+ int rc;
+
+ /* Always let maintenance notifications through. */
+ if (n->type == WATCH_TYPE_META)
+ return 0;
+
+ if (!cred)
+ return 0;
+ subj = smk_of_task(smack_cred(cred));
+ obj = smk_of_task(smack_cred(w_cred));
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
+ rc = smk_access(subj, obj, MAY_WRITE, &ad);
+ rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
+ return rc;
+}
+#endif /* CONFIG_WATCH_QUEUE */
+
/*
* Smack Audit hooks
*
@@ -4482,12 +4611,14 @@ static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
- return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
+ return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx,
+ ctxlen, 0);
}
static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
- return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
+ return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SMACK,
+ ctx, ctxlen, 0);
}
static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
@@ -4518,7 +4649,7 @@ static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
/*
* Get label from overlay inode and set it in create_sid
*/
- isp = smack_inode(d_inode(dentry->d_parent));
+ isp = smack_inode(d_inode(dentry));
skp = isp->smk_inode;
tsp->smk_task = skp;
*new = new_creds;
@@ -4575,12 +4706,85 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
return 0;
}
+#ifdef CONFIG_IO_URING
+/**
+ * smack_uring_override_creds - Is io_uring cred override allowed?
+ * @new: the target creds
+ *
+ * Check to see if the current task is allowed to override it's credentials
+ * to service an io_uring operation.
+ */
+static int smack_uring_override_creds(const struct cred *new)
+{
+ struct task_smack *tsp = smack_cred(current_cred());
+ struct task_smack *nsp = smack_cred(new);
+
+ /*
+ * Allow the degenerate case where the new Smack value is
+ * the same as the current Smack value.
+ */
+ if (tsp->smk_task == nsp->smk_task)
+ return 0;
+
+ if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
+ return 0;
+
+ return -EPERM;
+}
+
+/**
+ * smack_uring_sqpoll - check if a io_uring polling thread can be created
+ *
+ * Check to see if the current task is allowed to create a new io_uring
+ * kernel polling thread.
+ */
+static int smack_uring_sqpoll(void)
+{
+ if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred()))
+ return 0;
+
+ return -EPERM;
+}
+
+/**
+ * smack_uring_cmd - check on file operations for io_uring
+ * @ioucmd: the command in question
+ *
+ * Make a best guess about whether a io_uring "command" should
+ * be allowed. Use the same logic used for determining if the
+ * file could be opened for read in the absence of better criteria.
+ */
+static int smack_uring_cmd(struct io_uring_cmd *ioucmd)
+{
+ struct file *file = ioucmd->file;
+ struct smk_audit_info ad;
+ struct task_smack *tsp;
+ struct inode *inode;
+ int rc;
+
+ if (!file)
+ return -EINVAL;
+
+ tsp = smack_cred(file->f_cred);
+ inode = file_inode(file);
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
+ smk_ad_setfield_u_fs_path(&ad, file->f_path);
+ rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
+ rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
+
+ return rc;
+}
+
+#endif /* CONFIG_IO_URING */
+
struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
.lbs_cred = sizeof(struct task_smack),
.lbs_file = sizeof(struct smack_known *),
.lbs_inode = sizeof(struct inode_smack),
.lbs_ipc = sizeof(struct smack_known *),
.lbs_msg_msg = sizeof(struct smack_known *),
+ .lbs_superblock = sizeof(struct superblock_smack),
};
static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
@@ -4592,13 +4796,12 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
- LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
- LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
+ LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec),
LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
@@ -4640,7 +4843,8 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
LSM_HOOK_INIT(task_getsid, smack_task_getsid),
- LSM_HOOK_INIT(task_getsecid, smack_task_getsecid),
+ LSM_HOOK_INIT(current_getsecid_subj, smack_current_getsecid_subj),
+ LSM_HOOK_INIT(task_getsecid_obj, smack_task_getsecid_obj),
LSM_HOOK_INIT(task_setnice, smack_task_setnice),
LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
@@ -4691,6 +4895,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
+ LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security),
LSM_HOOK_INIT(sock_graft, smack_sock_graft),
LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
@@ -4701,8 +4906,15 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(key_free, smack_key_free),
LSM_HOOK_INIT(key_permission, smack_key_permission),
LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
+#ifdef CONFIG_KEY_NOTIFICATIONS
+ LSM_HOOK_INIT(watch_key, smack_watch_key),
+#endif
#endif /* CONFIG_KEYS */
+#ifdef CONFIG_WATCH_QUEUE
+ LSM_HOOK_INIT(post_notification, smack_post_notification),
+#endif
+
/* Audit hooks */
#ifdef CONFIG_AUDIT
LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
@@ -4719,6 +4931,11 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
+#ifdef CONFIG_IO_URING
+ LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds),
+ LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll),
+ LSM_HOOK_INIT(uring_cmd, smack_uring_cmd),
+#endif
};
@@ -4760,15 +4977,9 @@ static __init int smack_init(void)
struct cred *cred = (struct cred *) current->cred;
struct task_smack *tsp;
- smack_inode_cache = KMEM_CACHE(inode_smack, 0);
- if (!smack_inode_cache)
- return -ENOMEM;
-
smack_rule_cache = KMEM_CACHE(smack_rule, 0);
- if (!smack_rule_cache) {
- kmem_cache_destroy(smack_inode_cache);
+ if (!smack_rule_cache)
return -ENOMEM;
- }
/*
* Set the security state for the initial task.
diff --git a/security/smack/smack_netfilter.c b/security/smack/smack_netfilter.c
index fc7399b45373..b945c1d3a743 100644
--- a/security/smack/smack_netfilter.c
+++ b/security/smack/smack_netfilter.c
@@ -18,27 +18,7 @@
#include <net/net_namespace.h>
#include "smack.h"
-#if IS_ENABLED(CONFIG_IPV6)
-
-static unsigned int smack_ipv6_output(void *priv,
- struct sk_buff *skb,
- const struct nf_hook_state *state)
-{
- struct sock *sk = skb_to_full_sk(skb);
- struct socket_smack *ssp;
- struct smack_known *skp;
-
- if (sk && sk->sk_security) {
- ssp = sk->sk_security;
- skp = ssp->smk_out;
- skb->secmark = skp->smk_secid;
- }
-
- return NF_ACCEPT;
-}
-#endif /* IPV6 */
-
-static unsigned int smack_ipv4_output(void *priv,
+static unsigned int smack_ip_output(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
@@ -57,14 +37,14 @@ static unsigned int smack_ipv4_output(void *priv,
static const struct nf_hook_ops smack_nf_ops[] = {
{
- .hook = smack_ipv4_output,
+ .hook = smack_ip_output,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_SELINUX_FIRST,
},
#if IS_ENABLED(CONFIG_IPV6)
{
- .hook = smack_ipv6_output,
+ .hook = smack_ip_output,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_SELINUX_FIRST,
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index e3e05c04dbd1..4b58526450d4 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -23,6 +23,7 @@
#include <linux/ctype.h>
#include <linux/audit.h>
#include <linux/magic.h>
+#include <linux/mount.h>
#include <linux/fs_context.h>
#include "smack.h"
@@ -380,7 +381,7 @@ static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule,
* @data: string to be parsed, null terminated
* @rule: Will be filled with Smack parsed rule
* @import: if non-zero, import labels
- * @tokens: numer of substrings expected in data
+ * @tokens: number of substrings expected in data
*
* Returns number of processed bytes on success, -ERRNO on failure.
*/
@@ -693,9 +694,7 @@ static void smk_cipso_doi(void)
printk(KERN_WARNING "%s:%d remove rc = %d\n",
__func__, __LINE__, rc);
- doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL);
- if (doip == NULL)
- panic("smack: Failed to initialize cipso DOI.\n");
+ doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL | __GFP_NOFAIL);
doip->map.std = NULL;
doip->doi = smk_cipso_doi_value;
doip->type = CIPSO_V4_MAP_PASS;
@@ -714,7 +713,7 @@ static void smk_cipso_doi(void)
if (rc != 0) {
printk(KERN_WARNING "%s:%d map add rc = %d\n",
__func__, __LINE__, rc);
- kfree(doip);
+ netlbl_cfg_cipsov4_del(doip->doi, &nai);
return;
}
}
@@ -831,6 +830,7 @@ static int smk_open_cipso(struct inode *inode, struct file *file)
static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
size_t count, loff_t *ppos, int format)
{
+ struct netlbl_lsm_catmap *old_cat;
struct smack_known *skp;
struct netlbl_lsm_secattr ncats;
char mapcatset[SMK_CIPSOLEN];
@@ -855,6 +855,8 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
if (format == SMK_FIXED24_FMT &&
(count < SMK_CIPSOMIN || count > SMK_CIPSOMAX))
return -EINVAL;
+ if (count > PAGE_SIZE)
+ return -EINVAL;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
@@ -878,11 +880,21 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
else
rule += strlen(skp->smk_known) + 1;
+ if (rule > data + count) {
+ rc = -EOVERFLOW;
+ goto out;
+ }
+
ret = sscanf(rule, "%d", &maplevel);
- if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)
+ if (ret != 1 || maplevel < 0 || maplevel > SMACK_CIPSO_MAXLEVEL)
goto out;
rule += SMK_DIGITLEN;
+ if (rule > data + count) {
+ rc = -EOVERFLOW;
+ goto out;
+ }
+
ret = sscanf(rule, "%d", &catlen);
if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
goto out;
@@ -895,6 +907,10 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
for (i = 0; i < catlen; i++) {
rule += SMK_DIGITLEN;
+ if (rule > data + count) {
+ rc = -EOVERFLOW;
+ goto out;
+ }
ret = sscanf(rule, "%u", &cat);
if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM)
goto out;
@@ -904,10 +920,16 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
if (rc >= 0) {
- netlbl_catmap_free(skp->smk_netlabel.attr.mls.cat);
+ old_cat = skp->smk_netlabel.attr.mls.cat;
skp->smk_netlabel.attr.mls.cat = ncats.attr.mls.cat;
skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl;
+ synchronize_rcu();
+ netlbl_catmap_free(old_cat);
rc = count;
+ /*
+ * This mapping may have been cached, so clear the cache.
+ */
+ netlbl_cache_invalidate();
}
out:
@@ -1149,7 +1171,7 @@ static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
return -EPERM;
if (*ppos != 0)
return -EINVAL;
- if (count < SMK_NETLBLADDRMIN)
+ if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
return -EINVAL;
data = memdup_user_nul(buf, count);
@@ -1171,7 +1193,6 @@ static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
rc = -EINVAL;
goto free_out;
}
- m = BEBITS;
masks = 32;
}
if (masks > BEBITS) {
@@ -1409,7 +1430,7 @@ static ssize_t smk_write_net6addr(struct file *file, const char __user *buf,
return -EPERM;
if (*ppos != 0)
return -EINVAL;
- if (count < SMK_NETLBLADDRMIN)
+ if (count < SMK_NETLBLADDRMIN || count > PAGE_SIZE - 1)
return -EINVAL;
data = memdup_user_nul(buf, count);
@@ -1816,6 +1837,10 @@ static ssize_t smk_write_ambient(struct file *file, const char __user *buf,
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
+ /* Enough data must be present */
+ if (count == 0 || count > PAGE_SIZE)
+ return -EINVAL;
+
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
@@ -1924,7 +1949,7 @@ static void smk_list_swap_rcu(struct list_head *public,
* smk_parse_label_list - parse list of Smack labels, separated by spaces
*
* @data: the string to parse
- * @private: destination list
+ * @list: destination list
*
* Returns zero on success or error code, as appropriate
*/
@@ -1955,7 +1980,7 @@ static int smk_parse_label_list(char *data, struct list_head *list)
/**
* smk_destroy_label_list - destroy a list of smack_known_list_elem
- * @head: header pointer of the list to destroy
+ * @list: header pointer of the list to destroy
*/
void smk_destroy_label_list(struct list_head *list)
{
@@ -1987,6 +2012,9 @@ static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
+ if (count > PAGE_SIZE)
+ return -EINVAL;
+
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
@@ -2074,6 +2102,9 @@ static ssize_t smk_write_unconfined(struct file *file, const char __user *buf,
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
+ if (count > PAGE_SIZE)
+ return -EINVAL;
+
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
@@ -2113,7 +2144,7 @@ static const struct file_operations smk_unconfined_ops = {
* smk_read_logging - read() for /smack/logging
* @filp: file pointer, not actually used
* @buf: where to put the result
- * @cn: maximum to send along
+ * @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
@@ -2254,6 +2285,7 @@ static const struct file_operations smk_load_self_ops = {
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
+ * @format: /smack/load or /smack/load2 or /smack/change-rule format.
*/
static ssize_t smk_user_access(struct file *file, const char __user *buf,
size_t count, loff_t *ppos, int format)
@@ -2629,6 +2661,10 @@ static ssize_t smk_write_syslog(struct file *file, const char __user *buf,
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
+ /* Enough data must be present */
+ if (count == 0 || count > PAGE_SIZE)
+ return -EINVAL;
+
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
@@ -2710,7 +2746,6 @@ static int smk_open_relabel_self(struct inode *inode, struct file *file)
static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- struct task_smack *tsp = smack_cred(current_cred());
char *data;
int rc;
LIST_HEAD(list_tmp);
@@ -2722,10 +2757,13 @@ static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
return -EPERM;
/*
+ * No partial write.
* Enough data must be present.
*/
if (*ppos != 0)
return -EINVAL;
+ if (count == 0 || count > PAGE_SIZE)
+ return -EINVAL;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
@@ -2735,11 +2773,21 @@ static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
kfree(data);
if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
+ struct cred *new;
+ struct task_smack *tsp;
+
+ new = prepare_creds();
+ if (!new) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ tsp = smack_cred(new);
smk_destroy_label_list(&tsp->smk_relabel);
list_splice(&list_tmp, &tsp->smk_relabel);
+ commit_creds(new);
return count;
}
-
+out:
smk_destroy_label_list(&list_tmp);
return rc;
}
@@ -2927,15 +2975,6 @@ static struct file_system_type smk_fs_type = {
static struct vfsmount *smackfs_mount;
-static int __init smk_preset_netlabel(struct smack_known *skp)
-{
- skp->smk_netlabel.domain = skp->smk_known;
- skp->smk_netlabel.flags =
- NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
- return smk_netlbl_mls(smack_cipso_direct, skp->smk_known,
- &skp->smk_netlabel, strlen(skp->smk_known));
-}
-
/**
* init_smk_fs - get the smackfs superblock
*
@@ -2974,19 +3013,19 @@ static int __init init_smk_fs(void)
smk_cipso_doi();
smk_unlbl_ambient(NULL);
- rc = smk_preset_netlabel(&smack_known_floor);
+ rc = smack_populate_secattr(&smack_known_floor);
if (err == 0 && rc < 0)
err = rc;
- rc = smk_preset_netlabel(&smack_known_hat);
+ rc = smack_populate_secattr(&smack_known_hat);
if (err == 0 && rc < 0)
err = rc;
- rc = smk_preset_netlabel(&smack_known_huh);
+ rc = smack_populate_secattr(&smack_known_huh);
if (err == 0 && rc < 0)
err = rc;
- rc = smk_preset_netlabel(&smack_known_star);
+ rc = smack_populate_secattr(&smack_known_star);
if (err == 0 && rc < 0)
err = rc;
- rc = smk_preset_netlabel(&smack_known_web);
+ rc = smack_populate_secattr(&smack_known_web);
if (err == 0 && rc < 0)
err = rc;