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authorDavid Howells <dhowells@redhat.com>2008-11-14 10:39:19 +1100
committerJames Morris <jmorris@namei.org>2008-11-14 10:39:19 +1100
commit275bb41e9d058fbb327e7642f077e1beaeac162e (patch)
tree049fdbb39ca43e7b3b9abf36ad279b31488121bc /security/selinux
parentc69e8d9c01db2adc503464993c358901c9af9de4 (diff)
downloadlinux-2.6.38-lt-ux500-275bb41e9d058fbb327e7642f077e1beaeac162e.tar.gz
CRED: Wrap access to SELinux's task SID
Wrap access to SELinux's task SID, using task_sid() and current_sid() as appropriate. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/selinux')
-rw-r--r--security/selinux/hooks.c412
1 files changed, 218 insertions, 194 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 658435dce37..3f3de565c24 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -172,10 +172,35 @@ static int cred_alloc_security(struct cred *cred)
return 0;
}
+/*
+ * get the security ID of a task
+ */
+static inline u32 task_sid(const struct task_struct *task)
+{
+ const struct task_security_struct *tsec;
+ u32 sid;
+
+ rcu_read_lock();
+ tsec = __task_cred(task)->security;
+ sid = tsec->sid;
+ rcu_read_unlock();
+ return sid;
+}
+
+/*
+ * get the security ID of the current task
+ */
+static inline u32 current_sid(void)
+{
+ const struct task_security_struct *tsec = current_cred()->security;
+
+ return tsec->sid;
+}
+
static int inode_alloc_security(struct inode *inode)
{
- struct task_security_struct *tsec = current->cred->security;
struct inode_security_struct *isec;
+ u32 sid = current_sid();
isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
if (!isec)
@@ -186,7 +211,7 @@ static int inode_alloc_security(struct inode *inode)
isec->inode = inode;
isec->sid = SECINITSID_UNLABELED;
isec->sclass = SECCLASS_FILE;
- isec->task_sid = tsec->sid;
+ isec->task_sid = sid;
inode->i_security = isec;
return 0;
@@ -208,15 +233,15 @@ static void inode_free_security(struct inode *inode)
static int file_alloc_security(struct file *file)
{
- struct task_security_struct *tsec = current->cred->security;
struct file_security_struct *fsec;
+ u32 sid = current_sid();
fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
if (!fsec)
return -ENOMEM;
- fsec->sid = tsec->sid;
- fsec->fown_sid = tsec->sid;
+ fsec->sid = sid;
+ fsec->fown_sid = sid;
file->f_security = fsec;
return 0;
@@ -331,8 +356,9 @@ static const match_table_t tokens = {
static int may_context_mount_sb_relabel(u32 sid,
struct superblock_security_struct *sbsec,
- struct task_security_struct *tsec)
+ const struct cred *cred)
{
+ const struct task_security_struct *tsec = cred->security;
int rc;
rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
@@ -347,8 +373,9 @@ static int may_context_mount_sb_relabel(u32 sid,
static int may_context_mount_inode_relabel(u32 sid,
struct superblock_security_struct *sbsec,
- struct task_security_struct *tsec)
+ const struct cred *cred)
{
+ const struct task_security_struct *tsec = cred->security;
int rc;
rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
FILESYSTEM__RELABELFROM, NULL);
@@ -546,8 +573,8 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag,
static int selinux_set_mnt_opts(struct super_block *sb,
struct security_mnt_opts *opts)
{
+ const struct cred *cred = current_cred();
int rc = 0, i;
- struct task_security_struct *tsec = current->cred->security;
struct superblock_security_struct *sbsec = sb->s_security;
const char *name = sb->s_type->name;
struct inode *inode = sbsec->sb->s_root->d_inode;
@@ -673,8 +700,7 @@ static int selinux_set_mnt_opts(struct super_block *sb,
/* sets the context of the superblock for the fs being mounted. */
if (fscontext_sid) {
-
- rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
+ rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
if (rc)
goto out;
@@ -688,12 +714,14 @@ static int selinux_set_mnt_opts(struct super_block *sb,
*/
if (context_sid) {
if (!fscontext_sid) {
- rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
+ rc = may_context_mount_sb_relabel(context_sid, sbsec,
+ cred);
if (rc)
goto out;
sbsec->sid = context_sid;
} else {
- rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
+ rc = may_context_mount_inode_relabel(context_sid, sbsec,
+ cred);
if (rc)
goto out;
}
@@ -705,7 +733,8 @@ static int selinux_set_mnt_opts(struct super_block *sb,
}
if (rootcontext_sid) {
- rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
+ rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
+ cred);
if (rc)
goto out;
@@ -723,7 +752,7 @@ static int selinux_set_mnt_opts(struct super_block *sb,
if (defcontext_sid != sbsec->def_sid) {
rc = may_context_mount_inode_relabel(defcontext_sid,
- sbsec, tsec);
+ sbsec, cred);
if (rc)
goto out;
}
@@ -1338,18 +1367,23 @@ static inline u32 signal_to_av(int sig)
return perm;
}
-/* Check permission betweeen a pair of tasks, e.g. signal checks,
- fork check, ptrace check, etc. */
-static int task_has_perm(struct task_struct *tsk1,
- struct task_struct *tsk2,
+/*
+ * Check permission betweeen a pair of tasks, e.g. signal checks,
+ * fork check, ptrace check, etc.
+ * tsk1 is the actor and tsk2 is the target
+ */
+static int task_has_perm(const struct task_struct *tsk1,
+ const struct task_struct *tsk2,
u32 perms)
{
- struct task_security_struct *tsec1, *tsec2;
+ const struct task_security_struct *__tsec1, *__tsec2;
+ u32 sid1, sid2;
- tsec1 = tsk1->cred->security;
- tsec2 = tsk2->cred->security;
- return avc_has_perm(tsec1->sid, tsec2->sid,
- SECCLASS_PROCESS, perms, NULL);
+ rcu_read_lock();
+ __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
+ __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
+ rcu_read_unlock();
+ return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
}
#if CAP_LAST_CAP > 63
@@ -1360,15 +1394,13 @@ static int task_has_perm(struct task_struct *tsk1,
static int task_has_capability(struct task_struct *tsk,
int cap, int audit)
{
- struct task_security_struct *tsec;
struct avc_audit_data ad;
struct av_decision avd;
u16 sclass;
+ u32 sid = task_sid(tsk);
u32 av = CAP_TO_MASK(cap);
int rc;
- tsec = tsk->cred->security;
-
AVC_AUDIT_DATA_INIT(&ad, CAP);
ad.tsk = tsk;
ad.u.cap = cap;
@@ -1386,9 +1418,9 @@ static int task_has_capability(struct task_struct *tsk,
BUG();
}
- rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, sclass, av, 0, &avd);
+ rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
if (audit == SECURITY_CAP_AUDIT)
- avc_audit(tsec->sid, tsec->sid, sclass, av, &avd, rc, &ad);
+ avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
return rc;
}
@@ -1396,11 +1428,9 @@ static int task_has_capability(struct task_struct *tsk,
static int task_has_system(struct task_struct *tsk,
u32 perms)
{
- struct task_security_struct *tsec;
-
- tsec = tsk->cred->security;
+ u32 sid = task_sid(tsk);
- return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
+ return avc_has_perm(sid, SECINITSID_KERNEL,
SECCLASS_SYSTEM, perms, NULL);
}
@@ -1412,14 +1442,14 @@ static int inode_has_perm(struct task_struct *tsk,
u32 perms,
struct avc_audit_data *adp)
{
- struct task_security_struct *tsec;
struct inode_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid;
if (unlikely(IS_PRIVATE(inode)))
return 0;
- tsec = tsk->cred->security;
+ sid = task_sid(tsk);
isec = inode->i_security;
if (!adp) {
@@ -1428,7 +1458,7 @@ static int inode_has_perm(struct task_struct *tsk,
ad.u.fs.inode = inode;
}
- return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
+ return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
}
/* Same as inode_has_perm, but pass explicit audit data containing
@@ -1459,17 +1489,17 @@ static int file_has_perm(struct task_struct *tsk,
struct file *file,
u32 av)
{
- struct task_security_struct *tsec = tsk->cred->security;
struct file_security_struct *fsec = file->f_security;
struct inode *inode = file->f_path.dentry->d_inode;
struct avc_audit_data ad;
+ u32 sid = task_sid(tsk);
int rc;
AVC_AUDIT_DATA_INIT(&ad, FS);
ad.u.fs.path = file->f_path;
- if (tsec->sid != fsec->sid) {
- rc = avc_has_perm(tsec->sid, fsec->sid,
+ if (sid != fsec->sid) {
+ rc = avc_has_perm(sid, fsec->sid,
SECCLASS_FD,
FD__USE,
&ad);
@@ -1489,36 +1519,36 @@ static int may_create(struct inode *dir,
struct dentry *dentry,
u16 tclass)
{
- struct task_security_struct *tsec;
+ const struct cred *cred = current_cred();
+ const struct task_security_struct *tsec = cred->security;
struct inode_security_struct *dsec;
struct superblock_security_struct *sbsec;
- u32 newsid;
+ u32 sid, newsid;
struct avc_audit_data ad;
int rc;
- tsec = current->cred->security;
dsec = dir->i_security;
sbsec = dir->i_sb->s_security;
+ sid = tsec->sid;
+ newsid = tsec->create_sid;
+
AVC_AUDIT_DATA_INIT(&ad, FS);
ad.u.fs.path.dentry = dentry;
- rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
+ rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
DIR__ADD_NAME | DIR__SEARCH,
&ad);
if (rc)
return rc;
- if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
- newsid = tsec->create_sid;
- } else {
- rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
- &newsid);
+ if (!newsid || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) {
+ rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
if (rc)
return rc;
}
- rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
+ rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
if (rc)
return rc;
@@ -1531,11 +1561,9 @@ static int may_create(struct inode *dir,
static int may_create_key(u32 ksid,
struct task_struct *ctx)
{
- struct task_security_struct *tsec;
-
- tsec = ctx->cred->security;
+ u32 sid = task_sid(ctx);
- return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
+ return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
}
#define MAY_LINK 0
@@ -1548,13 +1576,12 @@ static int may_link(struct inode *dir,
int kind)
{
- struct task_security_struct *tsec;
struct inode_security_struct *dsec, *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
u32 av;
int rc;
- tsec = current->cred->security;
dsec = dir->i_security;
isec = dentry->d_inode->i_security;
@@ -1563,7 +1590,7 @@ static int may_link(struct inode *dir,
av = DIR__SEARCH;
av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
- rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
+ rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
if (rc)
return rc;
@@ -1583,7 +1610,7 @@ static int may_link(struct inode *dir,
return 0;
}
- rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
+ rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
return rc;
}
@@ -1592,14 +1619,13 @@ static inline int may_rename(struct inode *old_dir,
struct inode *new_dir,
struct dentry *new_dentry)
{
- struct task_security_struct *tsec;
struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
u32 av;
int old_is_dir, new_is_dir;
int rc;
- tsec = current->cred->security;
old_dsec = old_dir->i_security;
old_isec = old_dentry->d_inode->i_security;
old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
@@ -1608,16 +1634,16 @@ static inline int may_rename(struct inode *old_dir,
AVC_AUDIT_DATA_INIT(&ad, FS);
ad.u.fs.path.dentry = old_dentry;
- rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
+ rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
DIR__REMOVE_NAME | DIR__SEARCH, &ad);
if (rc)
return rc;
- rc = avc_has_perm(tsec->sid, old_isec->sid,
+ rc = avc_has_perm(sid, old_isec->sid,
old_isec->sclass, FILE__RENAME, &ad);
if (rc)
return rc;
if (old_is_dir && new_dir != old_dir) {
- rc = avc_has_perm(tsec->sid, old_isec->sid,
+ rc = avc_has_perm(sid, old_isec->sid,
old_isec->sclass, DIR__REPARENT, &ad);
if (rc)
return rc;
@@ -1627,13 +1653,13 @@ static inline int may_rename(struct inode *old_dir,
av = DIR__ADD_NAME | DIR__SEARCH;
if (new_dentry->d_inode)
av |= DIR__REMOVE_NAME;
- rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
+ rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
if (rc)
return rc;
if (new_dentry->d_inode) {
new_isec = new_dentry->d_inode->i_security;
new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
- rc = avc_has_perm(tsec->sid, new_isec->sid,
+ rc = avc_has_perm(sid, new_isec->sid,
new_isec->sclass,
(new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
if (rc)
@@ -1649,13 +1675,11 @@ static int superblock_has_perm(struct task_struct *tsk,
u32 perms,
struct avc_audit_data *ad)
{
- struct task_security_struct *tsec;
struct superblock_security_struct *sbsec;
+ u32 sid = task_sid(tsk);
- tsec = tsk->cred->security;
sbsec = sb->s_security;
- return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
- perms, ad);
+ return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
}
/* Convert a Linux mode and permission mask to an access vector. */
@@ -1751,10 +1775,9 @@ static int selinux_ptrace_may_access(struct task_struct *child,
return rc;
if (mode == PTRACE_MODE_READ) {
- struct task_security_struct *tsec = current->cred->security;
- struct task_security_struct *csec = child->cred->security;
- return avc_has_perm(tsec->sid, csec->sid,
- SECCLASS_FILE, FILE__READ, NULL);
+ u32 sid = current_sid();
+ u32 csid = task_sid(child);
+ return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
}
return task_has_perm(current, child, PROCESS__PTRACE);
@@ -1859,15 +1882,14 @@ static int selinux_sysctl(ctl_table *table, int op)
{
int error = 0;
u32 av;
- struct task_security_struct *tsec;
- u32 tsid;
+ u32 tsid, sid;
int rc;
rc = secondary_ops->sysctl(table, op);
if (rc)
return rc;
- tsec = current->cred->security;
+ sid = current_sid();
rc = selinux_sysctl_get_sid(table, (op == 0001) ?
SECCLASS_DIR : SECCLASS_FILE, &tsid);
@@ -1879,7 +1901,7 @@ static int selinux_sysctl(ctl_table *table, int op)
/* The op values are "defined" in sysctl.c, thereby creating
* a bad coupling between this module and sysctl.c */
if (op == 001) {
- error = avc_has_perm(tsec->sid, tsid,
+ error = avc_has_perm(sid, tsid,
SECCLASS_DIR, DIR__SEARCH, NULL);
} else {
av = 0;
@@ -1888,7 +1910,7 @@ static int selinux_sysctl(ctl_table *table, int op)
if (op & 002)
av |= FILE__WRITE;
if (av)
- error = avc_has_perm(tsec->sid, tsid,
+ error = avc_has_perm(sid, tsid,
SECCLASS_FILE, av, NULL);
}
@@ -2018,7 +2040,7 @@ static int selinux_bprm_set_security(struct linux_binprm *bprm)
if (bsec->set)
return 0;
- tsec = current->cred->security;
+ tsec = current_security();
isec = inode->i_security;
/* Default to the current task SID. */
@@ -2083,14 +2105,19 @@ static int selinux_bprm_check_security(struct linux_binprm *bprm)
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
{
- struct task_security_struct *tsec = current->cred->security;
+ const struct cred *cred = current_cred();
+ const struct task_security_struct *tsec = cred->security;
+ u32 sid, osid;
int atsecure = 0;
- if (tsec->osid != tsec->sid) {
+ sid = tsec->sid;
+ osid = tsec->osid;
+
+ if (osid != sid) {
/* Enable secure mode for SIDs transitions unless
the noatsecure permission is granted between
the two SIDs, i.e. ahp returns 0. */
- atsecure = avc_has_perm(tsec->osid, tsec->sid,
+ atsecure = avc_has_perm(osid, sid,
SECCLASS_PROCESS,
PROCESS__NOATSECURE, NULL);
}
@@ -2207,7 +2234,7 @@ static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
secondary_ops->bprm_apply_creds(bprm, unsafe);
- tsec = current->cred->security;
+ tsec = current_security();
bsec = bprm->security;
sid = bsec->sid;
@@ -2236,7 +2263,7 @@ static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
rcu_read_lock();
tracer = tracehook_tracer_task(current);
if (likely(tracer != NULL)) {
- sec = tracer->cred->security;
+ sec = __task_cred(tracer)->security;
ptsid = sec->sid;
}
rcu_read_unlock();
@@ -2267,7 +2294,7 @@ static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
int rc, i;
unsigned long flags;
- tsec = current->cred->security;
+ tsec = current_security();
bsec = bprm->security;
if (bsec->unsafe) {
@@ -2507,21 +2534,22 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
char **name, void **value,
size_t *len)
{
- struct task_security_struct *tsec;
+ const struct cred *cred = current_cred();
+ const struct task_security_struct *tsec = cred->security;
struct inode_security_struct *dsec;
struct superblock_security_struct *sbsec;
- u32 newsid, clen;
+ u32 sid, newsid, clen;
int rc;
char *namep = NULL, *context;
- tsec = current->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,
+ sid = tsec->sid;
+ newsid = tsec->create_sid;
+
+ if (!newsid || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) {
+ rc = security_transition_sid(sid, dsec->sid,
inode_mode_to_security_class(inode->i_mode),
&newsid);
if (rc) {
@@ -2699,12 +2727,11 @@ static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
- struct task_security_struct *tsec = current->cred->security;
struct inode *inode = dentry->d_inode;
struct inode_security_struct *isec = inode->i_security;
struct superblock_security_struct *sbsec;
struct avc_audit_data ad;
- u32 newsid;
+ u32 newsid, sid = current_sid();
int rc = 0;
if (strcmp(name, XATTR_NAME_SELINUX))
@@ -2720,7 +2747,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
AVC_AUDIT_DATA_INIT(&ad, FS);
ad.u.fs.path.dentry = dentry;
- rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
+ rc = avc_has_perm(sid, isec->sid, isec->sclass,
FILE__RELABELFROM, &ad);
if (rc)
return rc;
@@ -2734,12 +2761,12 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
if (rc)
return rc;
- rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
+ rc = avc_has_perm(sid, newsid, isec->sclass,
FILE__RELABELTO, &ad);
if (rc)
return rc;
- rc = security_validate_transition(isec->sid, newsid, tsec->sid,
+ rc = security_validate_transition(isec->sid, newsid, sid,
isec->sclass);
if (rc)
return rc;
@@ -2911,16 +2938,16 @@ static int selinux_revalidate_file_permission(struct file *file, int mask)
static int selinux_file_permission(struct file *file, int mask)
{
struct inode *inode = file->f_path.dentry->d_inode;
- struct task_security_struct *tsec = current->cred->security;
struct file_security_struct *fsec = file->f_security;
struct inode_security_struct *isec = inode->i_security;
+ u32 sid = current_sid();
if (!mask) {
/* No permission to check. Existence test. */
return 0;
}
- if (tsec->sid == fsec->sid && fsec->isid == isec->sid
+ if (sid == fsec->sid && fsec->isid == isec->sid
&& fsec->pseqno == avc_policy_seqno())
return selinux_netlbl_inode_permission(inode, mask);
@@ -2988,8 +3015,7 @@ static int selinux_file_mmap(struct file *file, unsigned long reqprot,
unsigned long addr, unsigned long addr_only)
{
int rc = 0;
- u32 sid = ((struct task_security_struct *)
- (current->cred->security))->sid;
+ u32 sid = current_sid();
if (addr < mmap_min_addr)
rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
@@ -3098,12 +3124,10 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd,
static int selinux_file_set_fowner(struct file *file)
{
- struct task_security_struct *tsec;
struct file_security_struct *fsec;
- tsec = current->cred->security;
fsec = file->f_security;
- fsec->fown_sid = tsec->sid;
+ fsec->fown_sid = current_sid();
return 0;
}
@@ -3112,14 +3136,13 @@ static int selinux_file_send_sigiotask(struct task_struct *tsk,
struct fown_struct *fown, int signum)
{
struct file *file;
+ u32 sid = current_sid();
u32 perm;
- struct task_security_struct *tsec;
struct file_security_struct *fsec;
/* struct fown_struct is never outside the context of a struct file */
file = container_of(fown, struct file, f_owner);
- tsec = tsk->cred->security;
fsec = file->f_security;
if (!signum)
@@ -3127,7 +3150,7 @@ static int selinux_file_send_sigiotask(struct task_struct *tsk,
else
perm = signal_to_av(signum);
- return avc_has_perm(fsec->fown_sid, tsec->sid,
+ return avc_has_perm(fsec->fown_sid, sid,
SECCLASS_PROCESS, perm, NULL);
}
@@ -3182,7 +3205,7 @@ static int selinux_cred_alloc_security(struct cred *cred)
struct task_security_struct *tsec1, *tsec2;
int rc;
- tsec1 = current->cred->security;
+ tsec1 = current_security();
rc = cred_alloc_security(cred);
if (rc)
@@ -3250,8 +3273,7 @@ static int selinux_task_getsid(struct task_struct *p)
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
- struct task_security_struct *tsec = p->cred->security;
- *secid = tsec->sid;
+ *secid = task_sid(p);
}
static int selinux_task_setgroups(struct group_info *group_info)
@@ -3332,7 +3354,6 @@ static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
{
u32 perm;
int rc;
- struct task_security_struct *tsec;
rc = secondary_ops->task_kill(p, info, sig, secid);
if (rc)
@@ -3342,9 +3363,9 @@ static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
perm = PROCESS__SIGNULL; /* null signal; existence test */
else
perm = signal_to_av(sig);
- tsec = p->cred->security;
if (secid)
- rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
+ rc = avc_has_perm(secid, task_sid(p),
+ SECCLASS_PROCESS, perm, NULL);
else
rc = task_has_perm(current, p, perm);
return rc;
@@ -3383,12 +3404,11 @@ static void selinux_task_reparent_to_init(struct task_struct *p)
static void selinux_task_to_inode(struct task_struct *p,
struct inode *inode)
{
- struct task_security_struct *tsec = p->cred->security;
struct inode_security_struct *isec = inode->i_security;
+ u32 sid = task_sid(p);
- isec->sid = tsec->sid;
+ isec->sid = sid;
isec->initialized = 1;
- return;
}
/* Returns error only if unable to parse addresses */
@@ -3627,19 +3647,19 @@ static int socket_has_perm(struct task_struct *task, struct socket *sock,
u32 perms)
{
struct inode_security_struct *isec;
- struct task_security_struct *tsec;
struct avc_audit_data ad;
+ u32 sid;
int err = 0;
- tsec = task->cred->security;
isec = SOCK_INODE(sock)->i_security;
if (isec->sid == SECINITSID_KERNEL)
goto out;
+ sid = task_sid(task);
AVC_AUDIT_DATA_INIT(&ad, NET);
ad.u.net.sk = sock->sk;
- err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
+ err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
out:
return err;
@@ -3648,18 +3668,20 @@ out:
static int selinux_socket_create(int family, int type,
int protocol, int kern)
{
+ const struct cred *cred = current_cred();
+ const struct task_security_struct *tsec = cred->security;
+ u32 sid, newsid;
+ u16 secclass;
int err = 0;
- struct task_security_struct *tsec;
- u32 newsid;
if (kern)
goto out;
- tsec = current->cred->security;
- newsid = tsec->sockcreate_sid ? : tsec->sid;
- err = avc_has_perm(tsec->sid, newsid,
- socket_type_to_security_class(family, type,
- protocol), SOCKET__CREATE, NULL);
+ sid = tsec->sid;
+ newsid = tsec->sockcreate_sid ?: sid;
+
+ secclass = socket_type_to_security_class(family, type, protocol);
+ err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
out:
return err;
@@ -3668,18 +3690,26 @@ out:
static int selinux_socket_post_create(struct socket *sock, int family,
int type, int protocol, int kern)
{
- int err = 0;
+ const struct cred *cred = current_cred();
+ const struct task_security_struct *tsec = cred->security;
struct inode_security_struct *isec;
- struct task_security_struct *tsec;
struct sk_security_struct *sksec;
- u32 newsid;
+ u32 sid, newsid;
+ int err = 0;
+
+ sid = tsec->sid;
+ newsid = tsec->sockcreate_sid;
isec = SOCK_INODE(sock)->i_security;
- tsec = current->cred->security;
- newsid = tsec->sockcreate_sid ? : tsec->sid;
+ if (kern)
+ isec->sid = SECINITSID_KERNEL;
+ else if (newsid)
+ isec->sid = newsid;
+ else
+ isec->sid = sid;
+
isec->sclass = socket_type_to_security_class(family, type, protocol);
- isec->sid = kern ? SECINITSID_KERNEL : newsid;
isec->initialized = 1;
if (sock->sk) {
@@ -3714,7 +3744,6 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in
if (family == PF_INET || family == PF_INET6) {
char *addrp;
struct inode_security_struct *isec;
- struct task_security_struct *tsec;
struct avc_audit_data ad;
struct sockaddr_in *addr4 = NULL;
struct sockaddr_in6 *addr6 = NULL;
@@ -3722,7 +3751,6 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in
struct sock *sk = sock->sk;
u32 sid, node_perm;
- tsec = current->cred->security;
isec = SOCK_INODE(sock)->i_security;
if (family == PF_INET) {
@@ -4763,15 +4791,16 @@ static int ipc_alloc_security(struct task_struct *task,
struct kern_ipc_perm *perm,
u16 sclass)
{
- struct task_security_struct *tsec = task->cred->security;
struct ipc_security_struct *isec;
+ u32 sid;
isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
if (!isec)
return -ENOMEM;
+ sid = task_sid(task);
isec->sclass = sclass;
- isec->sid = tsec->sid;
+ isec->sid = sid;
perm->security = isec;
return 0;
@@ -4809,17 +4838,16 @@ static void msg_msg_free_security(struct msg_msg *msg)
static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
u32 perms)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
- tsec = current->cred->security;
isec = ipc_perms->security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = ipc_perms->key;
- return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
+ return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
}
static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
@@ -4835,22 +4863,21 @@ static void selinux_msg_msg_free_security(struct msg_msg *msg)
/* message queue security operations */
static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
int rc;
rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
if (rc)
return rc;
- tsec = current->cred->security;
isec = msq->q_perm.security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = msq->q_perm.key;
- rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
+ rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
MSGQ__CREATE, &ad);
if (rc) {
ipc_free_security(&msq->q_perm);
@@ -4866,17 +4893,16 @@ static void selinux_msg_queue_free_security(struct msg_queue *msq)
static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
- tsec = current->cred->security;
isec = msq->q_perm.security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = msq->q_perm.key;
- return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
+ return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
MSGQ__ASSOCIATE, &ad);
}
@@ -4910,13 +4936,12 @@ static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct msg_security_struct *msec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
int rc;
- tsec = current->cred->security;
isec = msq->q_perm.security;
msec = msg->security;
@@ -4928,9 +4953,7 @@ static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
* Compute new sid based on current process and
* message queue this message will be stored in
*/
- rc = security_transition_sid(tsec->sid,
- isec->sid,
- SECCLASS_MSG,
+ rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
&msec->sid);
if (rc)
return rc;
@@ -4940,16 +4963,16 @@ static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
ad.u.ipc_id = msq->q_perm.key;
/* Can this process write to the queue? */
- rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
+ rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
MSGQ__WRITE, &ad);
if (!rc)
/* Can this process send the message */
- rc = avc_has_perm(tsec->sid, msec->sid,
- SECCLASS_MSG, MSG__SEND, &ad);
+ rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
+ MSG__SEND, &ad);
if (!rc)
/* Can the message be put in the queue? */
- rc = avc_has_perm(msec->sid, isec->sid,
- SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
+ rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
+ MSGQ__ENQUEUE, &ad);
return rc;
}
@@ -4958,23 +4981,22 @@ static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
struct task_struct *target,
long type, int mode)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct msg_security_struct *msec;
struct avc_audit_data ad;
+ u32 sid = task_sid(target);
int rc;
- tsec = target->cred->security;
isec = msq->q_perm.security;
msec = msg->security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = msq->q_perm.key;
- rc = avc_has_perm(tsec->sid, isec->sid,
+ rc = avc_has_perm(sid, isec->sid,
SECCLASS_MSGQ, MSGQ__READ, &ad);
if (!rc)
- rc = avc_has_perm(tsec->sid, msec->sid,
+ rc = avc_has_perm(sid, msec->sid,
SECCLASS_MSG, MSG__RECEIVE, &ad);
return rc;
}
@@ -4982,22 +5004,21 @@ static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
/* Shared Memory security operations */
static int selinux_shm_alloc_security(struct shmid_kernel *shp)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
int rc;
rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
if (rc)
return rc;
- tsec = current->cred->security;
isec = shp->shm_perm.security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = shp->shm_perm.key;
- rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
+ rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
SHM__CREATE, &ad);
if (rc) {
ipc_free_security(&shp->shm_perm);
@@ -5013,17 +5034,16 @@ static void selinux_shm_free_security(struct shmid_kernel *shp)
static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
- tsec = current->cred->security;
isec = shp->shm_perm.security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = shp->shm_perm.key;
- return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
+ return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
SHM__ASSOCIATE, &ad);
}
@@ -5081,22 +5101,21 @@ static int selinux_shm_shmat(struct shmid_kernel *shp,
/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
int rc;
rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
if (rc)
return rc;
- tsec = current->cred->security;
isec = sma->sem_perm.security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = sma->sem_perm.key;
- rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
+ rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
SEM__CREATE, &ad);
if (rc) {
ipc_free_security(&sma->sem_perm);
@@ -5112,17 +5131,16 @@ static void selinux_sem_free_security(struct sem_array *sma)
static int selinux_sem_associate(struct sem_array *sma, int semflg)
{
- struct task_security_struct *tsec;
struct ipc_security_struct *isec;
struct avc_audit_data ad;
+ u32 sid = current_sid();
- tsec = current->cred->security;
isec = sma->sem_perm.security;
AVC_AUDIT_DATA_INIT(&ad, IPC);
ad.u.ipc_id = sma->sem_perm.key;
- return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
+ return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
SEM__ASSOCIATE, &ad);
}
@@ -5212,7 +5230,7 @@ static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
static int selinux_getprocattr(struct task_struct *p,
char *name, char **value)
{
- struct task_security_struct *tsec;
+ const struct task_security_struct *__tsec;
u32 sid;
int error;
unsigned len;
@@ -5223,22 +5241,24 @@ static int selinux_getprocattr(struct task_struct *p,
return error;
}
- tsec = p->cred->security;
+ rcu_read_lock();
+ __tsec = __task_cred(p)->security;
if (!strcmp(name, "current"))
- sid = tsec->sid;
+ sid = __tsec->sid;
else if (!strcmp(name, "prev"))
- sid = tsec->osid;
+ sid = __tsec->osid;
else if (!strcmp(name, "exec"))
- sid = tsec->exec_sid;
+ sid = __tsec->exec_sid;
else if (!strcmp(name, "fscreate"))
- sid = tsec->create_sid;
+ sid = __tsec->create_sid;
else if (!strcmp(name, "keycreate"))
- sid = tsec->keycreate_sid;
+ sid = __tsec->keycreate_sid;
else if (!strcmp(name, "sockcreate"))
- sid = tsec->sockcreate_sid;
+ sid = __tsec->sockcreate_sid;
else
- return -EINVAL;
+ goto invalid;
+ rcu_read_unlock();
if (!sid)
return 0;
@@ -5247,6 +5267,10 @@ static int selinux_getprocattr(struct task_struct *p,
if (error)
return error;
return len;
+
+invalid:
+ rcu_read_unlock();
+ return -EINVAL;
}
static int selinux_setprocattr(struct task_struct *p,
@@ -5360,9 +5384,7 @@ boundary_ok:
rcu_read_lock();
tracer = tracehook_tracer_task(p);
if (tracer != NULL) {
- struct task_security_struct *ptsec =
- tracer->cred->security;
- u32 ptsid = ptsec->sid;
+ u32 ptsid = task_sid(tracer);
rcu_read_unlock();
error = avc_has_perm_noaudit(ptsid, sid,
SECCLASS_PROCESS,
@@ -5405,19 +5427,22 @@ static void selinux_release_secctx(char *secdata, u32 seclen)
static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
unsigned long flags)
{
- struct task_security_struct *tsec = tsk->cred->security;
+ const struct task_security_struct *__tsec;
struct key_security_struct *ksec;
ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
if (!ksec)
return -ENOMEM;
- if (tsec->keycreate_sid)
- ksec->sid = tsec->keycreate_sid;
+ rcu_read_lock();
+ __tsec = __task_cred(tsk)->security;
+ if (__tsec->keycreate_sid)
+ ksec->sid = __tsec->keycreate_sid;
else
- ksec->sid = tsec->sid;
- k->security = ksec;
+ ksec->sid = __tsec->sid;
+ rcu_read_unlock();
+ k->security = ksec;
return 0;
}
@@ -5434,13 +5459,8 @@ static int selinux_key_permission(key_ref_t key_ref,
key_perm_t perm)
{
struct key *key;
- struct task_security_struct *tsec;
struct key_security_struct *ksec;
-
- key = key_ref_to_ptr(key_ref);
-
- tsec = ctx->cred->security;
- ksec = key->security;
+ u32 sid;
/* if no specific permissions are requested, we skip the
permission check. No serious, additional covert channels
@@ -5448,8 +5468,12 @@ static int selinux_key_permission(key_ref_t key_ref,
if (perm == 0)
return 0;
- return avc_has_perm(tsec->sid, ksec->sid,
- SECCLASS_KEY, perm, NULL);
+ sid = task_sid(ctx);
+
+ key = key_ref_to_ptr(key_ref);
+ ksec = key->security;
+
+ return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
}
static int selinux_key_getsecurity(struct key *key, char **_buffer)