diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 1258 |
1 files changed, 672 insertions, 586 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index f85597a4d73..dbeaa783b2a 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -156,33 +156,62 @@ static int selinux_secmark_enabled(void) return (atomic_read(&selinux_secmark_refcount) > 0); } -/* Allocate and free functions for each kind of security blob. */ - -static int task_alloc_security(struct task_struct *task) +/* + * initialise the security for the init task + */ +static void cred_init_security(void) { + struct cred *cred = (struct cred *) current->real_cred; struct task_security_struct *tsec; tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); if (!tsec) - return -ENOMEM; + panic("SELinux: Failed to initialize initial task.\n"); - tsec->osid = tsec->sid = SECINITSID_UNLABELED; - task->security = tsec; + tsec->osid = tsec->sid = SECINITSID_KERNEL; + cred->security = tsec; +} - return 0; +/* + * get the security ID of a set of credentials + */ +static inline u32 cred_sid(const struct cred *cred) +{ + const struct task_security_struct *tsec; + + tsec = cred->security; + return tsec->sid; } -static void task_free_security(struct task_struct *task) +/* + * get the objective security ID of a task + */ +static inline u32 task_sid(const struct task_struct *task) { - struct task_security_struct *tsec = task->security; - task->security = NULL; - kfree(tsec); + u32 sid; + + rcu_read_lock(); + sid = cred_sid(__task_cred(task)); + rcu_read_unlock(); + return sid; +} + +/* + * get the subjective security ID of the current task + */ +static inline u32 current_sid(void) +{ + const struct task_security_struct *tsec = current_cred()->security; + + return tsec->sid; } +/* Allocate and free functions for each kind of security blob. */ + static int inode_alloc_security(struct inode *inode) { - struct task_security_struct *tsec = current->security; struct inode_security_struct *isec; + u32 sid = current_sid(); isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); if (!isec) @@ -193,7 +222,7 @@ 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; @@ -215,15 +244,15 @@ static void inode_free_security(struct inode *inode) static int file_alloc_security(struct file *file) { - struct task_security_struct *tsec = current->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; @@ -338,8 +367,9 @@ 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, @@ -354,8 +384,9 @@ 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); @@ -553,8 +584,8 @@ 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->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; @@ -671,7 +702,7 @@ static int selinux_set_mnt_opts(struct super_block *sb, sbsec->proc = 1; /* Determine the labeling behavior to use for this filesystem type. */ - rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); + rc = security_fs_use(sbsec->proc ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); if (rc) { printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", __func__, sb->s_type->name, rc); @@ -680,8 +711,7 @@ 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; @@ -695,12 +725,14 @@ 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; } @@ -712,7 +744,8 @@ 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; @@ -730,7 +763,7 @@ 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; } @@ -1345,18 +1378,53 @@ 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 between a pair of credentials + * fork check, ptrace check, etc. + */ +static int cred_has_perm(const struct cred *actor, + const struct cred *target, u32 perms) { - struct task_security_struct *tsec1, *tsec2; + u32 asid = cred_sid(actor), tsid = cred_sid(target); - tsec1 = tsk1->security; - tsec2 = tsk2->security; - return avc_has_perm(tsec1->sid, tsec2->sid, - SECCLASS_PROCESS, perms, NULL); + return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); +} + +/* + * Check permission between a pair of tasks, e.g. signal checks, + * fork check, ptrace check, etc. + * tsk1 is the actor and tsk2 is the target + * - this uses the default subjective creds of tsk1 + */ +static int task_has_perm(const struct task_struct *tsk1, + const struct task_struct *tsk2, + u32 perms) +{ + const struct task_security_struct *__tsec1, *__tsec2; + u32 sid1, sid2; + + 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); +} + +/* + * Check permission between current and another task, e.g. signal checks, + * fork check, ptrace check, etc. + * current is the actor and tsk2 is the target + * - this uses current's subjective creds + */ +static int current_has_perm(const struct task_struct *tsk, + u32 perms) +{ + u32 sid, tsid; + + sid = current_sid(); + tsid = task_sid(tsk); + return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); } #if CAP_LAST_CAP > 63 @@ -1365,14 +1433,14 @@ static int task_has_perm(struct task_struct *tsk1, /* Check whether a task is allowed to use a capability. */ static int task_has_capability(struct task_struct *tsk, - int cap) + 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); - - tsec = tsk->security; + int rc; AVC_AUDIT_DATA_INIT(&ad, CAP); ad.tsk = tsk; @@ -1390,37 +1458,39 @@ static int task_has_capability(struct task_struct *tsk, "SELinux: out of range capability %d\n", cap); BUG(); } - return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad); + + rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); + if (audit == SECURITY_CAP_AUDIT) + avc_audit(sid, sid, sclass, av, &avd, rc, &ad); + return rc; } /* Check whether a task is allowed to use a system operation. */ static int task_has_system(struct task_struct *tsk, u32 perms) { - struct task_security_struct *tsec; - - tsec = tsk->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); } /* Check whether a task has a particular permission to an inode. The 'adp' parameter is optional and allows other audit data to be passed (e.g. the dentry). */ -static int inode_has_perm(struct task_struct *tsk, +static int inode_has_perm(const struct cred *cred, struct inode *inode, 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->security; + sid = cred_sid(cred); isec = inode->i_security; if (!adp) { @@ -1429,23 +1499,24 @@ 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 the dentry to help the auditing code to more easily generate the pathname if needed. */ -static inline int dentry_has_perm(struct task_struct *tsk, +static inline int dentry_has_perm(const struct cred *cred, struct vfsmount *mnt, struct dentry *dentry, u32 av) { struct inode *inode = dentry->d_inode; struct avc_audit_data ad; + AVC_AUDIT_DATA_INIT(&ad, FS); ad.u.fs.path.mnt = mnt; ad.u.fs.path.dentry = dentry; - return inode_has_perm(tsk, inode, av, &ad); + return inode_has_perm(cred, inode, av, &ad); } /* Check whether a task can use an open file descriptor to @@ -1456,33 +1527,35 @@ static inline int dentry_has_perm(struct task_struct *tsk, has the same SID as the process. If av is zero, then access to the file is not checked, e.g. for cases where only the descriptor is affected like seek. */ -static int file_has_perm(struct task_struct *tsk, - struct file *file, - u32 av) +static int file_has_perm(const struct cred *cred, + struct file *file, + u32 av) { - struct task_security_struct *tsec = tsk->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 = cred_sid(cred); 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); if (rc) - return rc; + goto out; } /* av is zero if only checking access to the descriptor. */ + rc = 0; if (av) - return inode_has_perm(tsk, inode, av, &ad); + rc = inode_has_perm(cred, inode, av, &ad); - return 0; +out: + return rc; } /* Check whether a task can create a file. */ @@ -1490,36 +1563,36 @@ 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->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; @@ -1532,11 +1605,9 @@ 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->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 @@ -1549,13 +1620,12 @@ 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->security; dsec = dir->i_security; isec = dentry->d_inode->i_security; @@ -1564,7 +1634,7 @@ 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; @@ -1584,7 +1654,7 @@ 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; } @@ -1593,14 +1663,13 @@ 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->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); @@ -1609,16 +1678,16 @@ 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; @@ -1628,13 +1697,13 @@ 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) @@ -1645,18 +1714,16 @@ static inline int may_rename(struct inode *old_dir, } /* Check whether a task can perform a filesystem operation. */ -static int superblock_has_perm(struct task_struct *tsk, +static int superblock_has_perm(const struct cred *cred, struct super_block *sb, u32 perms, struct avc_audit_data *ad) { - struct task_security_struct *tsec; struct superblock_security_struct *sbsec; + u32 sid = cred_sid(cred); - tsec = tsk->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. */ @@ -1687,15 +1754,39 @@ static inline u32 file_mask_to_av(int mode, int mask) return av; } +/* Convert a Linux file to an access vector. */ +static inline u32 file_to_av(struct file *file) +{ + u32 av = 0; + + if (file->f_mode & FMODE_READ) + av |= FILE__READ; + if (file->f_mode & FMODE_WRITE) { + if (file->f_flags & O_APPEND) + av |= FILE__APPEND; + else + av |= FILE__WRITE; + } + if (!av) { + /* + * Special file opened with flags 3 for ioctl-only use. + */ + av = FILE__IOCTL; + } + + return av; +} + /* - * Convert a file mask to an access vector and include the correct open + * Convert a file to an access vector and include the correct open * open permission. */ -static inline u32 open_file_mask_to_av(int mode, int mask) +static inline u32 open_file_to_av(struct file *file) { - u32 av = file_mask_to_av(mode, mask); + u32 av = file_to_av(file); if (selinux_policycap_openperm) { + mode_t mode = file->f_path.dentry->d_inode->i_mode; /* * lnk files and socks do not really have an 'open' */ @@ -1711,31 +1802,8 @@ static inline u32 open_file_mask_to_av(int mode, int mask) av |= DIR__OPEN; else printk(KERN_ERR "SELinux: WARNING: inside %s with " - "unknown mode:%x\n", __func__, mode); - } - return av; -} - -/* Convert a Linux file to an access vector. */ -static inline u32 file_to_av(struct file *file) -{ - u32 av = 0; - - if (file->f_mode & FMODE_READ) - av |= FILE__READ; - if (file->f_mode & FMODE_WRITE) { - if (file->f_flags & O_APPEND) - av |= FILE__APPEND; - else - av |= FILE__WRITE; + "unknown mode:%o\n", __func__, mode); } - if (!av) { - /* - * Special file opened with flags 3 for ioctl-only use. - */ - av = FILE__IOCTL; - } - return av; } @@ -1751,13 +1819,12 @@ static int selinux_ptrace_may_access(struct task_struct *child, return rc; if (mode == PTRACE_MODE_READ) { - struct task_security_struct *tsec = current->security; - struct task_security_struct *csec = child->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); + return current_has_perm(child, PROCESS__PTRACE); } static int selinux_ptrace_traceme(struct task_struct *parent) @@ -1776,40 +1843,37 @@ static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, { int error; - error = task_has_perm(current, target, PROCESS__GETCAP); + error = current_has_perm(target, PROCESS__GETCAP); if (error) return error; return secondary_ops->capget(target, effective, inheritable, permitted); } -static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, - kernel_cap_t *inheritable, kernel_cap_t *permitted) +static int selinux_capset(struct cred *new, const struct cred *old, + const kernel_cap_t *effective, + const kernel_cap_t *inheritable, + const kernel_cap_t *permitted) { int error; - error = secondary_ops->capset_check(target, effective, inheritable, permitted); + error = secondary_ops->capset(new, old, + effective, inheritable, permitted); if (error) return error; - return task_has_perm(current, target, PROCESS__SETCAP); -} - -static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, - kernel_cap_t *inheritable, kernel_cap_t *permitted) -{ - secondary_ops->capset_set(target, effective, inheritable, permitted); + return cred_has_perm(old, new, PROCESS__SETCAP); } -static int selinux_capable(struct task_struct *tsk, int cap) +static int selinux_capable(struct task_struct *tsk, int cap, int audit) { int rc; - rc = secondary_ops->capable(tsk, cap); + rc = secondary_ops->capable(tsk, cap, audit); if (rc) return rc; - return task_has_capability(tsk, cap); + return task_has_capability(tsk, cap, audit); } static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) @@ -1857,15 +1921,14 @@ 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->security; + sid = current_sid(); rc = selinux_sysctl_get_sid(table, (op == 0001) ? SECCLASS_DIR : SECCLASS_FILE, &tsid); @@ -1877,7 +1940,7 @@ 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; @@ -1886,7 +1949,7 @@ 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); } @@ -1895,6 +1958,7 @@ static int selinux_sysctl(ctl_table *table, int op) static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) { + const struct cred *cred = current_cred(); int rc = 0; if (!sb) @@ -1906,14 +1970,12 @@ static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) case Q_QUOTAOFF: case Q_SETINFO: case Q_SETQUOTA: - rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD, - NULL); + rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); break; case Q_GETFMT: case Q_GETINFO: case Q_GETQUOTA: - rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET, - NULL); + rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); break; default: rc = 0; /* let the kernel handle invalid cmds */ @@ -1924,7 +1986,9 @@ static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) static int selinux_quota_on(struct dentry *dentry) { - return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); } static int selinux_syslog(int type) @@ -1972,16 +2036,8 @@ static int selinux_syslog(int type) static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) { int rc, cap_sys_admin = 0; - struct task_security_struct *tsec = current->security; - - rc = secondary_ops->capable(current, CAP_SYS_ADMIN); - if (rc == 0) - rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, - SECCLASS_CAPABILITY, - CAP_TO_MASK(CAP_SYS_ADMIN), - 0, - NULL); + rc = selinux_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT); if (rc == 0) cap_sys_admin = 1; @@ -1990,59 +2046,45 @@ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) /* binprm security operations */ -static int selinux_bprm_alloc_security(struct linux_binprm *bprm) +static int selinux_bprm_set_creds(struct linux_binprm *bprm) { - struct bprm_security_struct *bsec; - - bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); - if (!bsec) - return -ENOMEM; - - bsec->sid = SECINITSID_UNLABELED; - bsec->set = 0; - - bprm->security = bsec; - return 0; -} - -static int selinux_bprm_set_security(struct linux_binprm *bprm) -{ - struct task_security_struct *tsec; - struct inode *inode = bprm->file->f_path.dentry->d_inode; + const struct task_security_struct *old_tsec; + struct task_security_struct *new_tsec; struct inode_security_struct *isec; - struct bprm_security_struct *bsec; - u32 newsid; struct avc_audit_data ad; + struct inode *inode = bprm->file->f_path.dentry->d_inode; int rc; - rc = secondary_ops->bprm_set_security(bprm); + rc = secondary_ops->bprm_set_creds(bprm); if (rc) return rc; - bsec = bprm->security; - - if (bsec->set) + /* SELinux context only depends on initial program or script and not + * the script interpreter */ + if (bprm->cred_prepared) return 0; - tsec = current->security; + old_tsec = current_security(); + new_tsec = bprm->cred->security; isec = inode->i_security; /* Default to the current task SID. */ - bsec->sid = tsec->sid; + new_tsec->sid = old_tsec->sid; + new_tsec->osid = old_tsec->sid; /* Reset fs, key, and sock SIDs on execve. */ - tsec->create_sid = 0; - tsec->keycreate_sid = 0; - tsec->sockcreate_sid = 0; + new_tsec->create_sid = 0; + new_tsec->keycreate_sid = 0; + new_tsec->sockcreate_sid = 0; - if (tsec->exec_sid) { - newsid = tsec->exec_sid; + if (old_tsec->exec_sid) { + new_tsec->sid = old_tsec->exec_sid; /* Reset exec SID on execve. */ - tsec->exec_sid = 0; + new_tsec->exec_sid = 0; } else { /* Check for a default transition on this program. */ - rc = security_transition_sid(tsec->sid, isec->sid, - SECCLASS_PROCESS, &newsid); + rc = security_transition_sid(old_tsec->sid, isec->sid, + SECCLASS_PROCESS, &new_tsec->sid); if (rc) return rc; } @@ -2051,33 +2093,63 @@ static int selinux_bprm_set_security(struct linux_binprm *bprm) ad.u.fs.path = bprm->file->f_path; if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) - newsid = tsec->sid; + new_tsec->sid = old_tsec->sid; - if (tsec->sid == newsid) { - rc = avc_has_perm(tsec->sid, isec->sid, + if (new_tsec->sid == old_tsec->sid) { + rc = avc_has_perm(old_tsec->sid, isec->sid, SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); if (rc) return rc; } else { /* Check permissions for the transition. */ - rc = avc_has_perm(tsec->sid, newsid, + rc = avc_has_perm(old_tsec->sid, new_tsec->sid, SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); if (rc) return rc; - rc = avc_has_perm(newsid, isec->sid, + rc = avc_has_perm(new_tsec->sid, isec->sid, SECCLASS_FILE, FILE__ENTRYPOINT, &ad); if (rc) return rc; - /* Clear any possibly unsafe personality bits on exec: */ - current->personality &= ~PER_CLEAR_ON_SETID; + /* Check for shared state */ + if (bprm->unsafe & LSM_UNSAFE_SHARE) { + rc = avc_has_perm(old_tsec->sid, new_tsec->sid, + SECCLASS_PROCESS, PROCESS__SHARE, + NULL); + if (rc) + return -EPERM; + } + + /* Make sure that anyone attempting to ptrace over a task that + * changes its SID has the appropriate permit */ + if (bprm->unsafe & + (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { + struct task_struct *tracer; + struct task_security_struct *sec; + u32 ptsid = 0; - /* Set the security field to the new SID. */ - bsec->sid = newsid; + rcu_read_lock(); + tracer = tracehook_tracer_task(current); + if (likely(tracer != NULL)) { + sec = __task_cred(tracer)->security; + ptsid = sec->sid; + } + rcu_read_unlock(); + + if (ptsid != 0) { + rc = avc_has_perm(ptsid, new_tsec->sid, + SECCLASS_PROCESS, + PROCESS__PTRACE, NULL); + if (rc) + return -EPERM; + } + } + + /* Clear any possibly unsafe personality bits on exec: */ + bprm->per_clear |= PER_CLEAR_ON_SETID; } - bsec->set = 1; return 0; } @@ -2086,35 +2158,34 @@ static int selinux_bprm_check_security(struct linux_binprm *bprm) return secondary_ops->bprm_check_security(bprm); } - static int selinux_bprm_secureexec(struct linux_binprm *bprm) { - struct task_security_struct *tsec = current->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, - SECCLASS_PROCESS, - PROCESS__NOATSECURE, NULL); + atsecure = avc_has_perm(osid, sid, + SECCLASS_PROCESS, + PROCESS__NOATSECURE, NULL); } return (atsecure || secondary_ops->bprm_secureexec(bprm)); } -static void selinux_bprm_free_security(struct linux_binprm *bprm) -{ - kfree(bprm->security); - bprm->security = NULL; -} - extern struct vfsmount *selinuxfs_mount; extern struct dentry *selinux_null; /* Derived from fs/exec.c:flush_old_files. */ -static inline void flush_unauthorized_files(struct files_struct *files) +static inline void flush_unauthorized_files(const struct cred *cred, + struct files_struct *files) { struct avc_audit_data ad; struct file *file, *devnull = NULL; @@ -2136,7 +2207,7 @@ static inline void flush_unauthorized_files(struct files_struct *files) interested in the inode-based check here. */ file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list); inode = file->f_path.dentry->d_inode; - if (inode_has_perm(current, inode, + if (inode_has_perm(cred, inode, FILE__READ | FILE__WRITE, NULL)) { drop_tty = 1; } @@ -2171,7 +2242,7 @@ static inline void flush_unauthorized_files(struct files_struct *files) file = fget(i); if (!file) continue; - if (file_has_perm(current, + if (file_has_perm(cred, file, file_to_av(file))) { sys_close(i); @@ -2185,7 +2256,10 @@ static inline void flush_unauthorized_files(struct files_struct *files) if (devnull) { get_file(devnull); } else { - devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); + devnull = dentry_open( + dget(selinux_null), + mntget(selinuxfs_mount), + O_RDWR, cred); if (IS_ERR(devnull)) { devnull = NULL; put_unused_fd(fd); @@ -2204,94 +2278,78 @@ static inline void flush_unauthorized_files(struct files_struct *files) spin_unlock(&files->file_lock); } -static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) +/* + * Prepare a process for imminent new credential changes due to exec + */ +static void selinux_bprm_committing_creds(struct linux_binprm *bprm) { - struct task_security_struct *tsec; - struct bprm_security_struct *bsec; - u32 sid; - int rc; - - secondary_ops->bprm_apply_creds(bprm, unsafe); - - tsec = current->security; + struct task_security_struct *new_tsec; + struct rlimit *rlim, *initrlim; + int rc, i; - bsec = bprm->security; - sid = bsec->sid; + secondary_ops->bprm_committing_creds(bprm); - tsec->osid = tsec->sid; - bsec->unsafe = 0; - if (tsec->sid != sid) { - /* Check for shared state. If not ok, leave SID - unchanged and kill. */ - if (unsafe & LSM_UNSAFE_SHARE) { - rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, - PROCESS__SHARE, NULL); - if (rc) { - bsec->unsafe = 1; - return; - } - } + new_tsec = bprm->cred->security; + if (new_tsec->sid == new_tsec->osid) + return; - /* Check for ptracing, and update the task SID if ok. - Otherwise, leave SID unchanged and kill. */ - if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { - struct task_struct *tracer; - struct task_security_struct *sec; - u32 ptsid = 0; + /* Close files for which the new task SID is not authorized. */ + flush_unauthorized_files(bprm->cred, current->files); - rcu_read_lock(); - tracer = tracehook_tracer_task(current); - if (likely(tracer != NULL)) { - sec = tracer->security; - ptsid = sec->sid; - } - rcu_read_unlock(); + /* Always clear parent death signal on SID transitions. */ + current->pdeath_signal = 0; - if (ptsid != 0) { - rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, - PROCESS__PTRACE, NULL); - if (rc) { - bsec->unsafe = 1; - return; - } - } + /* Check whether the new SID can inherit resource limits from the old + * SID. If not, reset all soft limits to the lower of the current + * task's hard limit and the init task's soft limit. + * + * Note that the setting of hard limits (even to lower them) can be + * controlled by the setrlimit check. The inclusion of the init task's + * soft limit into the computation is to avoid resetting soft limits + * higher than the default soft limit for cases where the default is + * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. + */ + rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, + PROCESS__RLIMITINH, NULL); + if (rc) { + for (i = 0; i < RLIM_NLIMITS; i++) { + rlim = current->signal->rlim + i; + initrlim = init_task.signal->rlim + i; + rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); } - tsec->sid = sid; + update_rlimit_cpu(rlim->rlim_cur); } } /* - * called after apply_creds without the task lock held + * Clean up the process immediately after the installation of new credentials + * due to exec */ -static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) +static void selinux_bprm_committed_creds(struct linux_binprm *bprm) { - struct task_security_struct *tsec; - struct rlimit *rlim, *initrlim; + const struct task_security_struct *tsec = current_security(); struct itimerval itimer; - struct bprm_security_struct *bsec; + struct sighand_struct *psig; + u32 osid, sid; int rc, i; + unsigned long flags; - tsec = current->security; - bsec = bprm->security; + secondary_ops->bprm_committed_creds(bprm); - if (bsec->unsafe) { - force_sig_specific(SIGKILL, current); - return; - } - if (tsec->osid == tsec->sid) + osid = tsec->osid; + sid = tsec->sid; + + if (sid == osid) return; - /* Close files for which the new task SID is not authorized. */ - flush_unauthorized_files(current->files); - - /* Check whether the new SID can inherit signal state - from the old SID. If not, clear itimers to avoid - subsequent signal generation and flush and unblock - signals. This must occur _after_ the task SID has - been updated so that any kill done after the flush - will be checked against the new SID. */ - rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, - PROCESS__SIGINH, NULL); + /* Check whether the new SID can inherit signal state from the old SID. + * If not, clear itimers to avoid subsequent signal generation and + * flush and unblock signals. + * + * This must occur _after_ the task SID has been updated so that any + * kill done after the flush will be checked against the new SID. + */ + rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); if (rc) { memset(&itimer, 0, sizeof itimer); for (i = 0; i < 3; i++) @@ -2304,33 +2362,14 @@ static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) spin_unlock_irq(¤t->sighand->siglock); } - /* Always clear parent death signal on SID transitions. */ - current->pdeath_signal = 0; - - /* Check whether the new SID can inherit resource limits - from the old SID. If not, reset all soft limits to - the lower of the current task's hard limit and the init - task's soft limit. Note that the setting of hard limits - (even to lower them) can be controlled by the setrlimit - check. The inclusion of the init task's soft limit into - the computation is to avoid resetting soft limits higher - than the default soft limit for cases where the default - is lower than the hard limit, e.g. RLIMIT_CORE or - RLIMIT_STACK.*/ - rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, - PROCESS__RLIMITINH, NULL); - if (rc) { - for (i = 0; i < RLIM_NLIMITS; i++) { - rlim = current->signal->rlim + i; - initrlim = init_task.signal->rlim+i; - rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); - } - update_rlimit_cpu(rlim->rlim_cur); - } - - /* Wake up the parent if it is waiting so that it can - recheck wait permission to the new task SID. */ + /* Wake up the parent if it is waiting so that it can recheck + * wait permission to the new task SID. */ + read_lock_irq(&tasklist_lock); + psig = current->parent->sighand; + spin_lock_irqsave(&psig->siglock, flags); wake_up_interruptible(¤t->parent->signal->wait_chldexit); + spin_unlock_irqrestore(&psig->siglock, flags); + read_unlock_irq(&tasklist_lock); } /* superblock security operations */ @@ -2435,8 +2474,9 @@ out: return rc; } -static int selinux_sb_kern_mount(struct super_block *sb, void *data) +static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) { + const struct cred *cred = current_cred(); struct avc_audit_data ad; int rc; @@ -2444,18 +2484,23 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data) if (rc) return rc; + /* Allow all mounts performed by the kernel */ + if (flags & MS_KERNMOUNT) + return 0; + AVC_AUDIT_DATA_INIT(&ad, FS); ad.u.fs.path.dentry = sb->s_root; - return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); + return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); } static int selinux_sb_statfs(struct dentry *dentry) { + const struct cred *cred = current_cred(); struct avc_audit_data ad; AVC_AUDIT_DATA_INIT(&ad, FS); ad.u.fs.path.dentry = dentry->d_sb->s_root; - return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); + return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); } static int selinux_mount(char *dev_name, @@ -2464,6 +2509,7 @@ static int selinux_mount(char *dev_name, unsigned long flags, void *data) { + const struct cred *cred = current_cred(); int rc; rc = secondary_ops->sb_mount(dev_name, path, type, flags, data); @@ -2471,22 +2517,23 @@ static int selinux_mount(char *dev_name, return rc; if (flags & MS_REMOUNT) - return superblock_has_perm(current, path->mnt->mnt_sb, + return superblock_has_perm(cred, path->mnt->mnt_sb, FILESYSTEM__REMOUNT, NULL); else - return dentry_has_perm(current, path->mnt, path->dentry, + return dentry_has_perm(cred, path->mnt, path->dentry, FILE__MOUNTON); } static int selinux_umount(struct vfsmount *mnt, int flags) { + const struct cred *cred = current_cred(); int rc; rc = secondary_ops->sb_umount(mnt, flags); if (rc) return rc; - return superblock_has_perm(current, mnt->mnt_sb, + return superblock_has_perm(cred, mnt->mnt_sb, FILESYSTEM__UNMOUNT, NULL); } @@ -2506,21 +2553,22 @@ 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->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) { @@ -2623,21 +2671,25 @@ static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dent static int selinux_inode_readlink(struct dentry *dentry) { - return dentry_has_perm(current, NULL, dentry, FILE__READ); + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, NULL, dentry, FILE__READ); } static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) { + const struct cred *cred = current_cred(); int rc; rc = secondary_ops->inode_follow_link(dentry, nameidata); if (rc) return rc; - return dentry_has_perm(current, NULL, dentry, FILE__READ); + return dentry_has_perm(cred, NULL, dentry, FILE__READ); } static int selinux_inode_permission(struct inode *inode, int mask) { + const struct cred *cred = current_cred(); int rc; rc = secondary_ops->inode_permission(inode, mask); @@ -2649,12 +2701,13 @@ static int selinux_inode_permission(struct inode *inode, int mask) return 0; } - return inode_has_perm(current, inode, - open_file_mask_to_av(inode->i_mode, mask), NULL); + return inode_has_perm(cred, inode, + file_mask_to_av(inode->i_mode, mask), NULL); } static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) { + const struct cred *cred = current_cred(); int rc; rc = secondary_ops->inode_setattr(dentry, iattr); @@ -2666,18 +2719,22 @@ static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_ATIME_SET | ATTR_MTIME_SET)) - return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); + return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); - return dentry_has_perm(current, NULL, dentry, FILE__WRITE); + return dentry_has_perm(cred, NULL, dentry, FILE__WRITE); } static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) { - return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR); } static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) { + const struct cred *cred = current_cred(); + if (!strncmp(name, XATTR_SECURITY_PREFIX, sizeof XATTR_SECURITY_PREFIX - 1)) { if (!strcmp(name, XATTR_NAME_CAPS)) { @@ -2692,18 +2749,17 @@ static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) /* Not an attribute we recognize, so just check the ordinary setattr permission. */ - return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); + return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); } 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->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)) @@ -2719,7 +2775,7 @@ 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; @@ -2733,12 +2789,12 @@ 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; @@ -2778,12 +2834,16 @@ static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, static int selinux_inode_getxattr(struct dentry *dentry, const char *name) { - return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); } static int selinux_inode_listxattr(struct dentry *dentry) { - return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); + const struct cred *cred = current_cred(); + + return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); } static int selinux_inode_removexattr(struct dentry *dentry, const char *name) @@ -2806,7 +2866,6 @@ static int selinux_inode_getsecurity(const struct inode *inode, const char *name u32 size; int error; char *context = NULL; - struct task_security_struct *tsec = current->security; struct inode_security_struct *isec = inode->i_security; if (strcmp(name, XATTR_SELINUX_SUFFIX)) @@ -2821,13 +2880,7 @@ static int selinux_inode_getsecurity(const struct inode *inode, const char *name * and lack of permission just means that we fall back to the * in-core context value, not a denial. */ - error = secondary_ops->capable(current, CAP_MAC_ADMIN); - if (!error) - error = avc_has_perm_noaudit(tsec->sid, tsec->sid, - SECCLASS_CAPABILITY2, - CAPABILITY2__MAC_ADMIN, - 0, - NULL); + error = selinux_capable(current, CAP_MAC_ADMIN, SECURITY_CAP_NOAUDIT); if (!error) error = security_sid_to_context_force(isec->sid, &context, &size); @@ -2894,6 +2947,7 @@ static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) static int selinux_revalidate_file_permission(struct file *file, int mask) { + const struct cred *cred = current_cred(); int rc; struct inode *inode = file->f_path.dentry->d_inode; @@ -2906,7 +2960,7 @@ static int selinux_revalidate_file_permission(struct file *file, int mask) if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) mask |= MAY_APPEND; - rc = file_has_perm(current, file, + rc = file_has_perm(cred, file, file_mask_to_av(inode->i_mode, mask)); if (rc) return rc; @@ -2917,16 +2971,16 @@ 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->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); @@ -2946,6 +3000,7 @@ static void selinux_file_free_security(struct file *file) static int selinux_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { + const struct cred *cred = current_cred(); u32 av = 0; if (_IOC_DIR(cmd) & _IOC_WRITE) @@ -2955,11 +3010,14 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd, if (!av) av = FILE__IOCTL; - return file_has_perm(current, file, av); + return file_has_perm(cred, file, av); } static int file_map_prot_check(struct file *file, unsigned long prot, int shared) { + const struct cred *cred = current_cred(); + int rc = 0; + #ifndef CONFIG_PPC32 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { /* @@ -2967,9 +3025,9 @@ static int file_map_prot_check(struct file *file, unsigned long prot, int shared * private file mapping that will also be writable. * This has an additional check. */ - int rc = task_has_perm(current, current, PROCESS__EXECMEM); + rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); if (rc) - return rc; + goto error; } #endif @@ -2984,9 +3042,11 @@ static int file_map_prot_check(struct file *file, unsigned long prot, int shared if (prot & PROT_EXEC) av |= FILE__EXECUTE; - return file_has_perm(current, file, av); + return file_has_perm(cred, file, av); } - return 0; + +error: + return rc; } static int selinux_file_mmap(struct file *file, unsigned long reqprot, @@ -2994,7 +3054,7 @@ 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->security))->sid; + u32 sid = current_sid(); if (addr < mmap_min_addr) rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, @@ -3013,6 +3073,7 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, unsigned long prot) { + const struct cred *cred = current_cred(); int rc; rc = secondary_ops->file_mprotect(vma, reqprot, prot); @@ -3027,12 +3088,11 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, rc = 0; if (vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk) { - rc = task_has_perm(current, current, - PROCESS__EXECHEAP); + rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); } else if (!vma->vm_file && vma->vm_start <= vma->vm_mm->start_stack && vma->vm_end >= vma->vm_mm->start_stack) { - rc = task_has_perm(current, current, PROCESS__EXECSTACK); + rc = current_has_perm(current, PROCESS__EXECSTACK); } else if (vma->vm_file && vma->anon_vma) { /* * We are making executable a file mapping that has @@ -3041,8 +3101,7 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, * modified content. This typically should only * occur for text relocations. */ - rc = file_has_perm(current, vma->vm_file, - FILE__EXECMOD); + rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); } if (rc) return rc; @@ -3054,12 +3113,15 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, static int selinux_file_lock(struct file *file, unsigned int cmd) { - return file_has_perm(current, file, FILE__LOCK); + const struct cred *cred = current_cred(); + + return file_has_perm(cred, file, FILE__LOCK); } static int selinux_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) { + const struct cred *cred = current_cred(); int err = 0; switch (cmd) { @@ -3070,7 +3132,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, } if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { - err = file_has_perm(current, file, FILE__WRITE); + err = file_has_perm(cred, file, FILE__WRITE); break; } /* fall through */ @@ -3080,7 +3142,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, case F_GETOWN: case F_GETSIG: /* Just check FD__USE permission */ - err = file_has_perm(current, file, 0); + err = file_has_perm(cred, file, 0); break; case F_GETLK: case F_SETLK: @@ -3094,7 +3156,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, err = -EINVAL; break; } - err = file_has_perm(current, file, FILE__LOCK); + err = file_has_perm(cred, file, FILE__LOCK); break; } @@ -3103,12 +3165,10 @@ 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->security; fsec = file->f_security; - fsec->fown_sid = tsec->sid; + fsec->fown_sid = current_sid(); return 0; } @@ -3117,14 +3177,13 @@ 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->security; fsec = file->f_security; if (!signum) @@ -3132,20 +3191,23 @@ 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); } static int selinux_file_receive(struct file *file) { - return file_has_perm(current, file, file_to_av(file)); + const struct cred *cred = current_cred(); + + return file_has_perm(cred, file, file_to_av(file)); } -static int selinux_dentry_open(struct file *file) +static int selinux_dentry_open(struct file *file, const struct cred *cred) { struct file_security_struct *fsec; struct inode *inode; struct inode_security_struct *isec; + inode = file->f_path.dentry->d_inode; fsec = file->f_security; isec = inode->i_security; @@ -3166,7 +3228,7 @@ static int selinux_dentry_open(struct file *file) * new inode label or new policy. * This check is not redundant - do not remove. */ - return inode_has_perm(current, inode, file_to_av(file), NULL); + return inode_has_perm(cred, inode, open_file_to_av(file), NULL); } /* task security operations */ @@ -3179,36 +3241,88 @@ static int selinux_task_create(unsigned long clone_flags) if (rc) return rc; - return task_has_perm(current, current, PROCESS__FORK); + return current_has_perm(current, PROCESS__FORK); } -static int selinux_task_alloc_security(struct task_struct *tsk) +/* + * detach and free the LSM part of a set of credentials + */ +static void selinux_cred_free(struct cred *cred) { - struct task_security_struct *tsec1, *tsec2; - int rc; - - tsec1 = current->security; + struct task_security_struct *tsec = cred->security; + cred->security = NULL; + kfree(tsec); +} - rc = task_alloc_security(tsk); - if (rc) - return rc; - tsec2 = tsk->security; +/* + * prepare a new set of credentials for modification + */ +static int selinux_cred_prepare(struct cred *new, const struct cred *old, + gfp_t gfp) +{ + const struct task_security_struct *old_tsec; + struct task_security_struct *tsec; - tsec2->osid = tsec1->osid; - tsec2->sid = tsec1->sid; + old_tsec = old->security; - /* Retain the exec, fs, key, and sock SIDs across fork */ - tsec2->exec_sid = tsec1->exec_sid; - tsec2->create_sid = tsec1->create_sid; - tsec2->keycreate_sid = tsec1->keycreate_sid; - tsec2->sockcreate_sid = tsec1->sockcreate_sid; + tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); + if (!tsec) + return -ENOMEM; + new->security = tsec; return 0; } -static void selinux_task_free_security(struct task_struct *tsk) +/* + * commit new credentials + */ +static void selinux_cred_commit(struct cred *new, const struct cred *old) +{ + secondary_ops->cred_commit(new, old); +} + +/* + * set the security data for a kernel service + * - all the creation contexts are set to unlabelled + */ +static int selinux_kernel_act_as(struct cred *new, u32 secid) { - task_free_security(tsk); + struct task_security_struct *tsec = new->security; + u32 sid = current_sid(); + int ret; + + ret = avc_has_perm(sid, secid, + SECCLASS_KERNEL_SERVICE, + KERNEL_SERVICE__USE_AS_OVERRIDE, + NULL); + if (ret == 0) { + tsec->sid = secid; + tsec->create_sid = 0; + tsec->keycreate_sid = 0; + tsec->sockcreate_sid = 0; + } + return ret; +} + +/* + * set the file creation context in a security record to the same as the + * objective context of the specified inode + */ +static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) +{ + struct inode_security_struct *isec = inode->i_security; + struct task_security_struct *tsec = new->security; + u32 sid = current_sid(); + int ret; + + ret = avc_has_perm(sid, isec->sid, + SECCLASS_KERNEL_SERVICE, + KERNEL_SERVICE__CREATE_FILES_AS, + NULL); + + if (ret == 0) + tsec->create_sid = isec->sid; + return 0; } static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) @@ -3222,9 +3336,10 @@ static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) return 0; } -static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) +static int selinux_task_fix_setuid(struct cred *new, const struct cred *old, + int flags) { - return secondary_ops->task_post_setuid(id0, id1, id2, flags); + return secondary_ops->task_fix_setuid(new, old, flags); } static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) @@ -3235,23 +3350,22 @@ static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) { - return task_has_perm(current, p, PROCESS__SETPGID); + return current_has_perm(p, PROCESS__SETPGID); } static int selinux_task_getpgid(struct task_struct *p) { - return task_has_perm(current, p, PROCESS__GETPGID); + return current_has_perm(p, PROCESS__GETPGID); } static int selinux_task_getsid(struct task_struct *p) { - return task_has_perm(current, p, PROCESS__GETSESSION); + return current_has_perm(p, PROCESS__GETSESSION); } static void selinux_task_getsecid(struct task_struct *p, u32 *secid) { - struct task_security_struct *tsec = p->security; - *secid = tsec->sid; + *secid = task_sid(p); } static int selinux_task_setgroups(struct group_info *group_info) @@ -3268,7 +3382,7 @@ static int selinux_task_setnice(struct task_struct *p, int nice) if (rc) return rc; - return task_has_perm(current, p, PROCESS__SETSCHED); + return current_has_perm(p, PROCESS__SETSCHED); } static int selinux_task_setioprio(struct task_struct *p, int ioprio) @@ -3279,12 +3393,12 @@ static int selinux_task_setioprio(struct task_struct *p, int ioprio) if (rc) return rc; - return task_has_perm(current, p, PROCESS__SETSCHED); + return current_has_perm(p, PROCESS__SETSCHED); } static int selinux_task_getioprio(struct task_struct *p) { - return task_has_perm(current, p, PROCESS__GETSCHED); + return current_has_perm(p, PROCESS__GETSCHED); } static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) @@ -3299,9 +3413,9 @@ static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim /* Control the ability to change the hard limit (whether lowering or raising it), so that the hard limit can later be used as a safe reset point for the soft limit - upon context transitions. See selinux_bprm_apply_creds. */ + upon context transitions. See selinux_bprm_committing_creds. */ if (old_rlim->rlim_max != new_rlim->rlim_max) - return task_has_perm(current, current, PROCESS__SETRLIMIT); + return current_has_perm(current, PROCESS__SETRLIMIT); return 0; } @@ -3314,17 +3428,17 @@ static int selinux_task_setscheduler(struct task_struct *p, int policy, struct s if (rc) return rc; - return task_has_perm(current, p, PROCESS__SETSCHED); + return current_has_perm(p, PROCESS__SETSCHED); } static int selinux_task_getscheduler(struct task_struct *p) { - return task_has_perm(current, p, PROCESS__GETSCHED); + return current_has_perm(p, PROCESS__GETSCHED); } static int selinux_task_movememory(struct task_struct *p) { - return task_has_perm(current, p, PROCESS__SETSCHED); + return current_has_perm(p, PROCESS__SETSCHED); } static int selinux_task_kill(struct task_struct *p, struct siginfo *info, @@ -3332,7 +3446,6 @@ 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) @@ -3342,11 +3455,11 @@ 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->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); + rc = current_has_perm(p, perm); return rc; } @@ -3354,13 +3467,12 @@ static int selinux_task_prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, - unsigned long arg5, - long *rc_p) + unsigned long arg5) { /* The current prctl operations do not appear to require any SELinux controls since they merely observe or modify the state of the current process. */ - return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p); + return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5); } static int selinux_task_wait(struct task_struct *p) @@ -3368,27 +3480,14 @@ static int selinux_task_wait(struct task_struct *p) return task_has_perm(p, current, PROCESS__SIGCHLD); } -static void selinux_task_reparent_to_init(struct task_struct *p) -{ - struct task_security_struct *tsec; - - secondary_ops->task_reparent_to_init(p); - - tsec = p->security; - tsec->osid = tsec->sid; - tsec->sid = SECINITSID_KERNEL; - return; -} - static void selinux_task_to_inode(struct task_struct *p, struct inode *inode) { - struct task_security_struct *tsec = p->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 +3726,19 @@ 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->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 +3747,20 @@ 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->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 +3769,26 @@ 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->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 +3823,6 @@ 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 +3830,6 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in struct sock *sk = sock->sk; u32 sid, node_perm; - tsec = current->security; isec = SOCK_INODE(sock)->i_security; if (family == PF_INET) { @@ -4387,7 +4494,7 @@ static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) "SELinux: unrecognized netlink message" " type=%hu for sclass=%hu\n", nlh->nlmsg_type, isec->sclass); - if (!selinux_enforcing) + if (!selinux_enforcing || security_get_allow_unknown()) err = 0; } @@ -4628,7 +4735,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, * as fast and as clean as possible. */ if (selinux_compat_net || !selinux_policycap_netpeer) return selinux_ip_postroute_compat(skb, ifindex, family); - +#ifdef CONFIG_XFRM /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec * packet transformation so allow the packet to pass without any checks * since we'll have another chance to perform access control checks @@ -4637,7 +4744,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, * is NULL, in this case go ahead and apply access control. */ if (skb->dst != NULL && skb->dst->xfrm != NULL) return NF_ACCEPT; - +#endif secmark_active = selinux_secmark_enabled(); peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); if (!secmark_active && !peerlbl_active) @@ -4763,15 +4870,16 @@ static int ipc_alloc_security(struct task_struct *task, struct kern_ipc_perm *perm, u16 sclass) { - struct task_security_struct *tsec = task->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 +4917,16 @@ 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->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 +4942,21 @@ 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->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 +4972,16 @@ 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->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 +5015,12 @@ 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->security; isec = msq->q_perm.security; msec = msg->security; @@ -4928,9 +5032,7 @@ 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 +5042,16 @@ 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 +5060,22 @@ 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->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 +5083,21 @@ 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->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 +5113,16 @@ 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->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 +5180,21 @@ 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->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 +5210,16 @@ 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->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); } @@ -5212,33 +5309,35 @@ 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; if (current != p) { - error = task_has_perm(current, p, PROCESS__GETATTR); + error = current_has_perm(p, PROCESS__GETATTR); if (error) return error; } - tsec = p->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 +5346,10 @@ 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, @@ -5254,7 +5357,8 @@ static int selinux_setprocattr(struct task_struct *p, { struct task_security_struct *tsec; struct task_struct *tracer; - u32 sid = 0; + struct cred *new; + u32 sid = 0, ptsid; int error; char *str = value; @@ -5270,15 +5374,15 @@ static int selinux_setprocattr(struct task_struct *p, * above restriction is ever removed. */ if (!strcmp(name, "exec")) - error = task_has_perm(current, p, PROCESS__SETEXEC); + error = current_has_perm(p, PROCESS__SETEXEC); else if (!strcmp(name, "fscreate")) - error = task_has_perm(current, p, PROCESS__SETFSCREATE); + error = current_has_perm(p, PROCESS__SETFSCREATE); else if (!strcmp(name, "keycreate")) - error = task_has_perm(current, p, PROCESS__SETKEYCREATE); + error = current_has_perm(p, PROCESS__SETKEYCREATE); else if (!strcmp(name, "sockcreate")) - error = task_has_perm(current, p, PROCESS__SETSOCKCREATE); + error = current_has_perm(p, PROCESS__SETSOCKCREATE); else if (!strcmp(name, "current")) - error = task_has_perm(current, p, PROCESS__SETCURRENT); + error = current_has_perm(p, PROCESS__SETCURRENT); else error = -EINVAL; if (error) @@ -5301,87 +5405,75 @@ static int selinux_setprocattr(struct task_struct *p, return error; } + new = prepare_creds(); + if (!new) + return -ENOMEM; + /* Permission checking based on the specified context is performed during the actual operation (execve, open/mkdir/...), when we know the full context of the - operation. See selinux_bprm_set_security for the execve + operation. See selinux_bprm_set_creds for the execve checks and may_create for the file creation checks. The operation will then fail if the context is not permitted. */ - tsec = p->security; - if (!strcmp(name, "exec")) + tsec = new->security; + if (!strcmp(name, "exec")) { tsec->exec_sid = sid; - else if (!strcmp(name, "fscreate")) + } else if (!strcmp(name, "fscreate")) { tsec->create_sid = sid; - else if (!strcmp(name, "keycreate")) { + } else if (!strcmp(name, "keycreate")) { error = may_create_key(sid, p); if (error) - return error; + goto abort_change; tsec->keycreate_sid = sid; - } else if (!strcmp(name, "sockcreate")) + } else if (!strcmp(name, "sockcreate")) { tsec->sockcreate_sid = sid; - else if (!strcmp(name, "current")) { - struct av_decision avd; - + } else if (!strcmp(name, "current")) { + error = -EINVAL; if (sid == 0) - return -EINVAL; - /* - * SELinux allows to change context in the following case only. - * - Single threaded processes. - * - Multi threaded processes intend to change its context into - * more restricted domain (defined by TYPEBOUNDS statement). - */ - if (atomic_read(&p->mm->mm_users) != 1) { - struct task_struct *g, *t; - struct mm_struct *mm = p->mm; - read_lock(&tasklist_lock); - do_each_thread(g, t) { - if (t->mm == mm && t != p) { - read_unlock(&tasklist_lock); - error = security_bounded_transition(tsec->sid, sid); - if (!error) - goto boundary_ok; - - return error; - } - } while_each_thread(g, t); - read_unlock(&tasklist_lock); + goto abort_change; + + /* Only allow single threaded processes to change context */ + error = -EPERM; + if (!is_single_threaded(p)) { + error = security_bounded_transition(tsec->sid, sid); + if (error) + goto abort_change; } -boundary_ok: /* Check permissions for the transition. */ error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, PROCESS__DYNTRANSITION, NULL); if (error) - return error; + goto abort_change; /* Check for ptracing, and update the task SID if ok. Otherwise, leave SID unchanged and fail. */ + ptsid = 0; task_lock(p); - rcu_read_lock(); tracer = tracehook_tracer_task(p); - if (tracer != NULL) { - struct task_security_struct *ptsec = tracer->security; - u32 ptsid = ptsec->sid; - rcu_read_unlock(); - error = avc_has_perm_noaudit(ptsid, sid, - SECCLASS_PROCESS, - PROCESS__PTRACE, 0, &avd); - if (!error) - tsec->sid = sid; - task_unlock(p); - avc_audit(ptsid, sid, SECCLASS_PROCESS, - PROCESS__PTRACE, &avd, error, NULL); + if (tracer) + ptsid = task_sid(tracer); + task_unlock(p); + + if (tracer) { + error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, + PROCESS__PTRACE, NULL); if (error) - return error; - } else { - rcu_read_unlock(); - tsec->sid = sid; - task_unlock(p); + goto abort_change; } - } else - return -EINVAL; + tsec->sid = sid; + } else { + error = -EINVAL; + goto abort_change; + } + + commit_creds(new); return size; + +abort_change: + abort_creds(new); + return error; } static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) @@ -5401,22 +5493,23 @@ static void selinux_release_secctx(char *secdata, u32 seclen) #ifdef CONFIG_KEYS -static int selinux_key_alloc(struct key *k, struct task_struct *tsk, +static int selinux_key_alloc(struct key *k, const struct cred *cred, unsigned long flags) { - struct task_security_struct *tsec = tsk->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; + tsec = cred->security; if (tsec->keycreate_sid) ksec->sid = tsec->keycreate_sid; else ksec->sid = tsec->sid; - k->security = ksec; + k->security = ksec; return 0; } @@ -5429,17 +5522,12 @@ static void selinux_key_free(struct key *k) } static int selinux_key_permission(key_ref_t key_ref, - struct task_struct *ctx, - key_perm_t perm) + const struct cred *cred, + 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->security; - ksec = key->security; + u32 sid; /* if no specific permissions are requested, we skip the permission check. No serious, additional covert channels @@ -5447,8 +5535,12 @@ 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 = cred_sid(cred); + + 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) @@ -5473,8 +5565,7 @@ static struct security_operations selinux_ops = { .ptrace_may_access = selinux_ptrace_may_access, .ptrace_traceme = selinux_ptrace_traceme, .capget = selinux_capget, - .capset_check = selinux_capset_check, - .capset_set = selinux_capset_set, + .capset = selinux_capset, .sysctl = selinux_sysctl, .capable = selinux_capable, .quotactl = selinux_quotactl, @@ -5485,12 +5576,10 @@ static struct security_operations selinux_ops = { .netlink_send = selinux_netlink_send, .netlink_recv = selinux_netlink_recv, - .bprm_alloc_security = selinux_bprm_alloc_security, - .bprm_free_security = selinux_bprm_free_security, - .bprm_apply_creds = selinux_bprm_apply_creds, - .bprm_post_apply_creds = selinux_bprm_post_apply_creds, - .bprm_set_security = selinux_bprm_set_security, + .bprm_set_creds = selinux_bprm_set_creds, .bprm_check_security = selinux_bprm_check_security, + .bprm_committing_creds = selinux_bprm_committing_creds, + .bprm_committed_creds = selinux_bprm_committed_creds, .bprm_secureexec = selinux_bprm_secureexec, .sb_alloc_security = selinux_sb_alloc_security, @@ -5549,10 +5638,13 @@ static struct security_operations selinux_ops = { .dentry_open = selinux_dentry_open, .task_create = selinux_task_create, - .task_alloc_security = selinux_task_alloc_security, - .task_free_security = selinux_task_free_security, + .cred_free = selinux_cred_free, + .cred_prepare = selinux_cred_prepare, + .cred_commit = selinux_cred_commit, + .kernel_act_as = selinux_kernel_act_as, + .kernel_create_files_as = selinux_kernel_create_files_as, .task_setuid = selinux_task_setuid, - .task_post_setuid = selinux_task_post_setuid, + .task_fix_setuid = selinux_task_fix_setuid, .task_setgid = selinux_task_setgid, .task_setpgid = selinux_task_setpgid, .task_getpgid = selinux_task_getpgid, @@ -5569,7 +5661,6 @@ static struct security_operations selinux_ops = { .task_kill = selinux_task_kill, .task_wait = selinux_task_wait, .task_prctl = selinux_task_prctl, - .task_reparent_to_init = selinux_task_reparent_to_init, .task_to_inode = selinux_task_to_inode, .ipc_permission = selinux_ipc_permission, @@ -5665,8 +5756,6 @@ static struct security_operations selinux_ops = { static __init int selinux_init(void) { - struct task_security_struct *tsec; - if (!security_module_enable(&selinux_ops)) { selinux_enabled = 0; return 0; @@ -5680,10 +5769,7 @@ static __init int selinux_init(void) printk(KERN_INFO "SELinux: Initializing.\n"); /* Set the security state for the initial task. */ - if (task_alloc_security(current)) - panic("SELinux: Failed to initialize initial task.\n"); - tsec = current->security; - tsec->osid = tsec->sid = SECINITSID_KERNEL; + cred_init_security(); sel_inode_cache = kmem_cache_create("selinux_inode_security", sizeof(struct inode_security_struct), |