diff options
-rw-r--r-- | include/linux/cred.h | 59 | ||||
-rw-r--r-- | include/linux/fs.h | 2 | ||||
-rw-r--r-- | include/linux/lsm_hook_defs.h | 10 | ||||
-rw-r--r-- | include/linux/security.h | 20 | ||||
-rw-r--r-- | kernel/cred.c | 26 | ||||
-rw-r--r-- | security/apparmor/lsm.c | 4 | ||||
-rw-r--r-- | security/commoncap.c | 4 | ||||
-rw-r--r-- | security/security.c | 12 | ||||
-rw-r--r-- | security/selinux/hooks.c | 10 | ||||
-rw-r--r-- | security/tomoyo/tomoyo.c | 2 |
10 files changed, 97 insertions, 52 deletions
diff --git a/include/linux/cred.h b/include/linux/cred.h index 92f8d772da6f..af8d353a4b86 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -220,6 +220,20 @@ static inline bool cap_ambient_invariant_ok(const struct cred *cred) } /** + * get_new_cred_many - Get references on a new set of credentials + * @cred: The new credentials to reference + * @nr: Number of references to acquire + * + * Get references on the specified set of new credentials. The caller must + * release all acquired references. + */ +static inline struct cred *get_new_cred_many(struct cred *cred, int nr) +{ + atomic_add(nr, &cred->usage); + return cred; +} + +/** * get_new_cred - Get a reference on a new set of credentials * @cred: The new credentials to reference * @@ -228,16 +242,16 @@ static inline bool cap_ambient_invariant_ok(const struct cred *cred) */ static inline struct cred *get_new_cred(struct cred *cred) { - atomic_inc(&cred->usage); - return cred; + return get_new_cred_many(cred, 1); } /** - * get_cred - Get a reference on a set of credentials + * get_cred_many - Get references on a set of credentials * @cred: The credentials to reference + * @nr: Number of references to acquire * - * Get a reference on the specified set of credentials. The caller must - * release the reference. If %NULL is passed, it is returned with no action. + * Get references on the specified set of credentials. The caller must release + * all acquired reference. If %NULL is passed, it is returned with no action. * * This is used to deal with a committed set of credentials. Although the * pointer is const, this will temporarily discard the const and increment the @@ -245,14 +259,28 @@ static inline struct cred *get_new_cred(struct cred *cred) * accidental alteration of a set of credentials that should be considered * immutable. */ -static inline const struct cred *get_cred(const struct cred *cred) +static inline const struct cred *get_cred_many(const struct cred *cred, int nr) { struct cred *nonconst_cred = (struct cred *) cred; if (!cred) return cred; validate_creds(cred); nonconst_cred->non_rcu = 0; - return get_new_cred(nonconst_cred); + return get_new_cred_many(nonconst_cred, nr); +} + +/* + * get_cred - Get a reference on a set of credentials + * @cred: The credentials to reference + * + * Get a reference on the specified set of credentials. The caller must + * release the reference. If %NULL is passed, it is returned with no action. + * + * This is used to deal with a committed set of credentials. + */ +static inline const struct cred *get_cred(const struct cred *cred) +{ + return get_cred_many(cred, 1); } static inline const struct cred *get_cred_rcu(const struct cred *cred) @@ -270,6 +298,7 @@ static inline const struct cred *get_cred_rcu(const struct cred *cred) /** * put_cred - Release a reference to a set of credentials * @cred: The credentials to release + * @nr: Number of references to release * * Release a reference to a set of credentials, deleting them when the last ref * is released. If %NULL is passed, nothing is done. @@ -278,17 +307,29 @@ static inline const struct cred *get_cred_rcu(const struct cred *cred) * on task_struct are attached by const pointers to prevent accidental * alteration of otherwise immutable credential sets. */ -static inline void put_cred(const struct cred *_cred) +static inline void put_cred_many(const struct cred *_cred, int nr) { struct cred *cred = (struct cred *) _cred; if (cred) { validate_creds(cred); - if (atomic_dec_and_test(&(cred)->usage)) + if (atomic_sub_and_test(nr, &cred->usage)) __put_cred(cred); } } +/* + * put_cred - Release a reference to a set of credentials + * @cred: The credentials to release + * + * Release a reference to a set of credentials, deleting them when the last ref + * is released. If %NULL is passed, nothing is done. + */ +static inline void put_cred(const struct cred *cred) +{ + put_cred_many(cred, 1); +} + /** * current_cred - Access the current task's subjective credentials * diff --git a/include/linux/fs.h b/include/linux/fs.h index bd522c0ac267..c27c324ba58a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2478,7 +2478,7 @@ struct filename { }; static_assert(offsetof(struct filename, iname) % sizeof(long) == 0); -static inline struct mnt_idmap *file_mnt_idmap(struct file *file) +static inline struct mnt_idmap *file_mnt_idmap(const struct file *file) { return mnt_idmap(file->f_path.mnt); } diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index ac962c4cb44b..99b8176c3738 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -43,17 +43,17 @@ LSM_HOOK(int, 0, capset, struct cred *new, const struct cred *old, const kernel_cap_t *permitted) LSM_HOOK(int, 0, capable, const struct cred *cred, struct user_namespace *ns, int cap, unsigned int opts) -LSM_HOOK(int, 0, quotactl, int cmds, int type, int id, struct super_block *sb) +LSM_HOOK(int, 0, quotactl, int cmds, int type, int id, const struct super_block *sb) LSM_HOOK(int, 0, quota_on, struct dentry *dentry) LSM_HOOK(int, 0, syslog, int type) LSM_HOOK(int, 0, settime, const struct timespec64 *ts, const struct timezone *tz) LSM_HOOK(int, 0, vm_enough_memory, struct mm_struct *mm, long pages) LSM_HOOK(int, 0, bprm_creds_for_exec, struct linux_binprm *bprm) -LSM_HOOK(int, 0, bprm_creds_from_file, struct linux_binprm *bprm, struct file *file) +LSM_HOOK(int, 0, bprm_creds_from_file, struct linux_binprm *bprm, const struct file *file) LSM_HOOK(int, 0, bprm_check_security, struct linux_binprm *bprm) -LSM_HOOK(void, LSM_RET_VOID, bprm_committing_creds, struct linux_binprm *bprm) -LSM_HOOK(void, LSM_RET_VOID, bprm_committed_creds, struct linux_binprm *bprm) +LSM_HOOK(void, LSM_RET_VOID, bprm_committing_creds, const struct linux_binprm *bprm) +LSM_HOOK(void, LSM_RET_VOID, bprm_committed_creds, const struct linux_binprm *bprm) LSM_HOOK(int, 0, fs_context_submount, struct fs_context *fc, struct super_block *reference) LSM_HOOK(int, 0, fs_context_dup, struct fs_context *fc, struct fs_context *src_sc) @@ -66,7 +66,7 @@ LSM_HOOK(void, LSM_RET_VOID, sb_free_mnt_opts, void *mnt_opts) LSM_HOOK(int, 0, sb_eat_lsm_opts, char *orig, void **mnt_opts) LSM_HOOK(int, 0, sb_mnt_opts_compat, struct super_block *sb, void *mnt_opts) LSM_HOOK(int, 0, sb_remount, struct super_block *sb, void *mnt_opts) -LSM_HOOK(int, 0, sb_kern_mount, struct super_block *sb) +LSM_HOOK(int, 0, sb_kern_mount, const struct super_block *sb) LSM_HOOK(int, 0, sb_show_options, struct seq_file *m, struct super_block *sb) LSM_HOOK(int, 0, sb_statfs, struct dentry *dentry) LSM_HOOK(int, 0, sb_mount, const char *dev_name, const struct path *path, diff --git a/include/linux/security.h b/include/linux/security.h index 5f16eecde00b..1d1df326c881 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -151,7 +151,7 @@ extern int cap_capset(struct cred *new, const struct cred *old, const kernel_cap_t *effective, const kernel_cap_t *inheritable, const kernel_cap_t *permitted); -extern int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file); +extern int cap_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file); int cap_inode_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags); int cap_inode_removexattr(struct mnt_idmap *idmap, @@ -284,16 +284,16 @@ int security_capable(const struct cred *cred, struct user_namespace *ns, int cap, unsigned int opts); -int security_quotactl(int cmds, int type, int id, struct super_block *sb); +int security_quotactl(int cmds, int type, int id, const struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); int security_settime64(const struct timespec64 *ts, const struct timezone *tz); int security_vm_enough_memory_mm(struct mm_struct *mm, long pages); int security_bprm_creds_for_exec(struct linux_binprm *bprm); -int security_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file); +int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file); int security_bprm_check(struct linux_binprm *bprm); -void security_bprm_committing_creds(struct linux_binprm *bprm); -void security_bprm_committed_creds(struct linux_binprm *bprm); +void security_bprm_committing_creds(const struct linux_binprm *bprm); +void security_bprm_committed_creds(const struct linux_binprm *bprm); int security_fs_context_submount(struct fs_context *fc, struct super_block *reference); int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc); int security_fs_context_parse_param(struct fs_context *fc, struct fs_parameter *param); @@ -304,7 +304,7 @@ void security_free_mnt_opts(void **mnt_opts); int security_sb_eat_lsm_opts(char *options, void **mnt_opts); int security_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts); int security_sb_remount(struct super_block *sb, void *mnt_opts); -int security_sb_kern_mount(struct super_block *sb); +int security_sb_kern_mount(const struct super_block *sb); int security_sb_show_options(struct seq_file *m, struct super_block *sb); int security_sb_statfs(struct dentry *dentry); int security_sb_mount(const char *dev_name, const struct path *path, @@ -581,7 +581,7 @@ static inline int security_capable(const struct cred *cred, } static inline int security_quotactl(int cmds, int type, int id, - struct super_block *sb) + const struct super_block *sb) { return 0; } @@ -613,7 +613,7 @@ static inline int security_bprm_creds_for_exec(struct linux_binprm *bprm) } static inline int security_bprm_creds_from_file(struct linux_binprm *bprm, - struct file *file) + const struct file *file) { return cap_bprm_creds_from_file(bprm, file); } @@ -623,11 +623,11 @@ static inline int security_bprm_check(struct linux_binprm *bprm) return 0; } -static inline void security_bprm_committing_creds(struct linux_binprm *bprm) +static inline void security_bprm_committing_creds(const struct linux_binprm *bprm) { } -static inline void security_bprm_committed_creds(struct linux_binprm *bprm) +static inline void security_bprm_committed_creds(const struct linux_binprm *bprm) { } diff --git a/kernel/cred.c b/kernel/cred.c index 4dc0b27b5462..3c714cb31660 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -162,23 +162,29 @@ EXPORT_SYMBOL(__put_cred); */ void exit_creds(struct task_struct *tsk) { - struct cred *cred; + struct cred *real_cred, *cred; kdebug("exit_creds(%u,%p,%p,{%d,%d})", tsk->pid, tsk->real_cred, tsk->cred, atomic_read(&tsk->cred->usage), read_cred_subscribers(tsk->cred)); - cred = (struct cred *) tsk->real_cred; + real_cred = (struct cred *) tsk->real_cred; tsk->real_cred = NULL; - validate_creds(cred); - alter_cred_subscribers(cred, -1); - put_cred(cred); cred = (struct cred *) tsk->cred; tsk->cred = NULL; + validate_creds(cred); - alter_cred_subscribers(cred, -1); - put_cred(cred); + if (real_cred == cred) { + alter_cred_subscribers(cred, -2); + put_cred_many(cred, 2); + } else { + validate_creds(real_cred); + alter_cred_subscribers(real_cred, -1); + put_cred(real_cred); + alter_cred_subscribers(cred, -1); + put_cred(cred); + } #ifdef CONFIG_KEYS_REQUEST_CACHE key_put(tsk->cached_requested_key); @@ -355,8 +361,7 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) #endif clone_flags & CLONE_THREAD ) { - p->real_cred = get_cred(p->cred); - get_cred(p->cred); + p->real_cred = get_cred_many(p->cred, 2); alter_cred_subscribers(p->cred, 2); kdebug("share_creds(%p{%d,%d})", p->cred, atomic_read(&p->cred->usage), @@ -520,8 +525,7 @@ int commit_creds(struct cred *new) proc_id_connector(task, PROC_EVENT_GID); /* release the old obj and subj refs both */ - put_cred(old); - put_cred(old); + put_cred_many(old, 2); return 0; } EXPORT_SYMBOL(commit_creds); diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 108eccc5ada5..3fa325d5efac 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -734,7 +734,7 @@ fail: * apparmor_bprm_committing_creds - do task cleanup on committing new creds * @bprm: binprm for the exec (NOT NULL) */ -static void apparmor_bprm_committing_creds(struct linux_binprm *bprm) +static void apparmor_bprm_committing_creds(const struct linux_binprm *bprm) { struct aa_label *label = aa_current_raw_label(); struct aa_label *new_label = cred_label(bprm->cred); @@ -756,7 +756,7 @@ static void apparmor_bprm_committing_creds(struct linux_binprm *bprm) * apparmor_bprm_committed_creds() - do cleanup after new creds committed * @bprm: binprm for the exec (NOT NULL) */ -static void apparmor_bprm_committed_creds(struct linux_binprm *bprm) +static void apparmor_bprm_committed_creds(const struct linux_binprm *bprm) { /* clear out temporary/transitional state from the context */ aa_clear_task_ctx_trans(task_ctx(current)); diff --git a/security/commoncap.c b/security/commoncap.c index bc0521104197..8e8c630ce204 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -720,7 +720,7 @@ int get_vfs_caps_from_disk(struct mnt_idmap *idmap, * its xattrs and, if present, apply them to the proposed credentials being * constructed by execve(). */ -static int get_file_caps(struct linux_binprm *bprm, struct file *file, +static int get_file_caps(struct linux_binprm *bprm, const struct file *file, bool *effective, bool *has_fcap) { int rc = 0; @@ -882,7 +882,7 @@ static inline bool nonroot_raised_pE(struct cred *new, const struct cred *old, * * Return: 0 if successful, -ve on error. */ -int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file) +int cap_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) { /* Process setpcap binaries and capabilities for uid 0 */ const struct cred *old = current_cred(); diff --git a/security/security.c b/security/security.c index 23b129d482a7..dcb3e7014f9b 100644 --- a/security/security.c +++ b/security/security.c @@ -957,7 +957,7 @@ int security_capable(const struct cred *cred, * * Return: Returns 0 if permission is granted. */ -int security_quotactl(int cmds, int type, int id, struct super_block *sb) +int security_quotactl(int cmds, int type, int id, const struct super_block *sb) { return call_int_hook(quotactl, 0, cmds, type, id, sb); } @@ -1079,7 +1079,7 @@ int security_bprm_creds_for_exec(struct linux_binprm *bprm) * * Return: Returns 0 if the hook is successful and permission is granted. */ -int security_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file) +int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) { return call_int_hook(bprm_creds_from_file, 0, bprm, file); } @@ -1118,7 +1118,7 @@ int security_bprm_check(struct linux_binprm *bprm) * open file descriptors to which access will no longer be granted when the * attributes are changed. This is called immediately before commit_creds(). */ -void security_bprm_committing_creds(struct linux_binprm *bprm) +void security_bprm_committing_creds(const struct linux_binprm *bprm) { call_void_hook(bprm_committing_creds, bprm); } @@ -1134,7 +1134,7 @@ void security_bprm_committing_creds(struct linux_binprm *bprm) * process such as clearing out non-inheritable signal state. This is called * immediately after commit_creds(). */ -void security_bprm_committed_creds(struct linux_binprm *bprm) +void security_bprm_committed_creds(const struct linux_binprm *bprm) { call_void_hook(bprm_committed_creds, bprm); } @@ -1319,7 +1319,7 @@ EXPORT_SYMBOL(security_sb_remount); * * Return: Returns 0 if permission is granted. */ -int security_sb_kern_mount(struct super_block *sb) +int security_sb_kern_mount(const struct super_block *sb) { return call_int_hook(sb_kern_mount, 0, sb); } @@ -3957,7 +3957,7 @@ void security_inode_invalidate_secctx(struct inode *inode) EXPORT_SYMBOL(security_inode_invalidate_secctx); /** - * security_inode_notifysecctx() - Nofify the LSM of an inode's security label + * security_inode_notifysecctx() - Notify the LSM of an inode's security label * @inode: inode * @ctx: secctx * @ctxlen: length of secctx diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 2aa0e219d721..feda711c6b7b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1937,7 +1937,7 @@ static inline int may_rename(struct inode *old_dir, /* Check whether a task can perform a filesystem operation. */ static int superblock_has_perm(const struct cred *cred, - struct super_block *sb, + const struct super_block *sb, u32 perms, struct common_audit_data *ad) { @@ -2139,7 +2139,7 @@ static int selinux_capable(const struct cred *cred, struct user_namespace *ns, return cred_has_capability(cred, cap, opts, ns == &init_user_ns); } -static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) +static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) { const struct cred *cred = current_cred(); int rc = 0; @@ -2455,7 +2455,7 @@ static inline void flush_unauthorized_files(const struct cred *cred, /* * Prepare a process for imminent new credential changes due to exec */ -static void selinux_bprm_committing_creds(struct linux_binprm *bprm) +static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) { struct task_security_struct *new_tsec; struct rlimit *rlim, *initrlim; @@ -2501,7 +2501,7 @@ static void selinux_bprm_committing_creds(struct linux_binprm *bprm) * Clean up the process immediately after the installation of new credentials * due to exec */ -static void selinux_bprm_committed_creds(struct linux_binprm *bprm) +static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) { const struct task_security_struct *tsec = selinux_cred(current_cred()); u32 osid, sid; @@ -2721,7 +2721,7 @@ out_bad_option: return -EINVAL; } -static int selinux_sb_kern_mount(struct super_block *sb) +static int selinux_sb_kern_mount(const struct super_block *sb) { const struct cred *cred = current_cred(); struct common_audit_data ad; diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c index 25006fddc964..255f1b470295 100644 --- a/security/tomoyo/tomoyo.c +++ b/security/tomoyo/tomoyo.c @@ -52,7 +52,7 @@ static int tomoyo_cred_prepare(struct cred *new, const struct cred *old, * * @bprm: Pointer to "struct linux_binprm". */ -static void tomoyo_bprm_committed_creds(struct linux_binprm *bprm) +static void tomoyo_bprm_committed_creds(const struct linux_binprm *bprm) { /* Clear old_domain_info saved by execve() request. */ struct tomoyo_task *s = tomoyo_task(current); |