Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace rlimit handling update from Eric Biederman: "This is the work mainly by Alexey Gladkov to limit rlimits to the rlimits of the user that created a user namespace, and to allow users to have stricter limits on the resources created within a user namespace." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: cred: add missing return error code when set_cred_ucounts() failed ucounts: Silence warning in dec_rlimit_ucounts ucounts: Set ucount_max to the largest positive value the type can hold kselftests: Add test to check for rlimit changes in different user namespaces Reimplement RLIMIT_MEMLOCK on top of ucounts Reimplement RLIMIT_SIGPENDING on top of ucounts Reimplement RLIMIT_MSGQUEUE on top of ucounts Reimplement RLIMIT_NPROC on top of ucounts Use atomic_t for ucounts reference counting Add a reference to ucounts for each cred Increase size of ucounts to atomic_long_t
This commit is contained in:
Коммит
c54b245d01
|
@ -1360,6 +1360,10 @@ int begin_new_exec(struct linux_binprm * bprm)
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WRITE_ONCE(me->self_exec_id, me->self_exec_id + 1);
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flush_signal_handlers(me, 0);
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retval = set_cred_ucounts(bprm->cred);
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if (retval < 0)
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goto out_unlock;
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/*
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* install the new credentials for this executable
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*/
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@ -1874,7 +1878,7 @@ static int do_execveat_common(int fd, struct filename *filename,
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* whether NPROC limit is still exceeded.
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*/
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if ((current->flags & PF_NPROC_EXCEEDED) &&
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atomic_read(¤t_user()->processes) > rlimit(RLIMIT_NPROC)) {
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is_ucounts_overlimit(current_ucounts(), UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC))) {
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retval = -EAGAIN;
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goto out_ret;
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}
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@ -1446,7 +1446,7 @@ static int get_hstate_idx(int page_size_log)
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* otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
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*/
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struct file *hugetlb_file_setup(const char *name, size_t size,
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vm_flags_t acctflag, struct user_struct **user,
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vm_flags_t acctflag, struct ucounts **ucounts,
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int creat_flags, int page_size_log)
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{
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struct inode *inode;
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@ -1458,20 +1458,20 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
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if (hstate_idx < 0)
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return ERR_PTR(-ENODEV);
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*user = NULL;
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*ucounts = NULL;
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mnt = hugetlbfs_vfsmount[hstate_idx];
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if (!mnt)
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return ERR_PTR(-ENOENT);
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if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
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*user = current_user();
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if (user_shm_lock(size, *user)) {
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*ucounts = current_ucounts();
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if (user_shm_lock(size, *ucounts)) {
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task_lock(current);
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pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
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current->comm, current->pid);
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task_unlock(current);
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} else {
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*user = NULL;
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*ucounts = NULL;
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return ERR_PTR(-EPERM);
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}
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}
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@ -1498,9 +1498,9 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
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iput(inode);
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out:
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if (*user) {
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user_shm_unlock(size, *user);
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*user = NULL;
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if (*ucounts) {
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user_shm_unlock(size, *ucounts);
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*ucounts = NULL;
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}
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return file;
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}
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@ -284,7 +284,7 @@ static inline void task_sig(struct seq_file *m, struct task_struct *p)
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collect_sigign_sigcatch(p, &ignored, &caught);
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num_threads = get_nr_threads(p);
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rcu_read_lock(); /* FIXME: is this correct? */
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qsize = atomic_read(&__task_cred(p)->user->sigpending);
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qsize = get_ucounts_value(task_ucounts(p), UCOUNT_RLIMIT_SIGPENDING);
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rcu_read_unlock();
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qlim = task_rlimit(p, RLIMIT_SIGPENDING);
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unlock_task_sighand(p, &flags);
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@ -143,6 +143,7 @@ struct cred {
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#endif
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struct user_struct *user; /* real user ID subscription */
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struct user_namespace *user_ns; /* user_ns the caps and keyrings are relative to. */
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struct ucounts *ucounts;
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struct group_info *group_info; /* supplementary groups for euid/fsgid */
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/* RCU deletion */
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union {
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@ -169,6 +170,7 @@ extern int set_security_override_from_ctx(struct cred *, const char *);
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extern int set_create_files_as(struct cred *, struct inode *);
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extern int cred_fscmp(const struct cred *, const struct cred *);
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extern void __init cred_init(void);
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extern int set_cred_ucounts(struct cred *);
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/*
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* check for validity of credentials
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|
@ -369,6 +371,7 @@ static inline void put_cred(const struct cred *_cred)
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#define task_uid(task) (task_cred_xxx((task), uid))
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#define task_euid(task) (task_cred_xxx((task), euid))
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#define task_ucounts(task) (task_cred_xxx((task), ucounts))
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#define current_cred_xxx(xxx) \
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({ \
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@ -385,6 +388,7 @@ static inline void put_cred(const struct cred *_cred)
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#define current_fsgid() (current_cred_xxx(fsgid))
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#define current_cap() (current_cred_xxx(cap_effective))
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#define current_user() (current_cred_xxx(user))
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#define current_ucounts() (current_cred_xxx(ucounts))
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extern struct user_namespace init_user_ns;
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#ifdef CONFIG_USER_NS
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|
|
|
@ -451,7 +451,7 @@ static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode)
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extern const struct file_operations hugetlbfs_file_operations;
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extern const struct vm_operations_struct hugetlb_vm_ops;
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struct file *hugetlb_file_setup(const char *name, size_t size, vm_flags_t acct,
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struct user_struct **user, int creat_flags,
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struct ucounts **ucounts, int creat_flags,
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int page_size_log);
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static inline bool is_file_hugepages(struct file *file)
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|
@ -471,7 +471,7 @@ static inline struct hstate *hstate_inode(struct inode *i)
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#define is_file_hugepages(file) false
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static inline struct file *
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hugetlb_file_setup(const char *name, size_t size, vm_flags_t acctflag,
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struct user_struct **user, int creat_flags,
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struct ucounts **ucounts, int creat_flags,
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int page_size_log)
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{
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return ERR_PTR(-ENOSYS);
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|
|
|
@ -1709,8 +1709,8 @@ extern bool can_do_mlock(void);
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#else
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static inline bool can_do_mlock(void) { return false; }
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#endif
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extern int user_shm_lock(size_t, struct user_struct *);
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extern void user_shm_unlock(size_t, struct user_struct *);
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extern int user_shm_lock(size_t, struct ucounts *);
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extern void user_shm_unlock(size_t, struct ucounts *);
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/*
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* Parameter block passed down to zap_pte_range in exceptional cases.
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|
|
|
@ -12,16 +12,9 @@
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*/
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struct user_struct {
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refcount_t __count; /* reference count */
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atomic_t processes; /* How many processes does this user have? */
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atomic_t sigpending; /* How many pending signals does this user have? */
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#ifdef CONFIG_EPOLL
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atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
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#endif
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#ifdef CONFIG_POSIX_MQUEUE
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/* protected by mq_lock */
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unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
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#endif
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unsigned long locked_shm; /* How many pages of mlocked shm ? */
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unsigned long unix_inflight; /* How many files in flight in unix sockets */
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atomic_long_t pipe_bufs; /* how many pages are allocated in pipe buffers */
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|
|
|
@ -65,7 +65,7 @@ extern struct file *shmem_file_setup_with_mnt(struct vfsmount *mnt,
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extern int shmem_zero_setup(struct vm_area_struct *);
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extern unsigned long shmem_get_unmapped_area(struct file *, unsigned long addr,
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unsigned long len, unsigned long pgoff, unsigned long flags);
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extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
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extern int shmem_lock(struct file *file, int lock, struct ucounts *ucounts);
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#ifdef CONFIG_SHMEM
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extern const struct address_space_operations shmem_aops;
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static inline bool shmem_mapping(struct address_space *mapping)
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|
|
|
@ -13,6 +13,8 @@ typedef struct kernel_siginfo {
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__SIGINFO;
|
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} kernel_siginfo_t;
|
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|
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struct ucounts;
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||||
|
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/*
|
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* Real Time signals may be queued.
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*/
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|
@ -21,7 +23,7 @@ struct sigqueue {
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struct list_head list;
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int flags;
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kernel_siginfo_t info;
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struct user_struct *user;
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struct ucounts *ucounts;
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};
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/* flags values. */
|
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|
|
|
@ -54,9 +54,15 @@ enum ucount_type {
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UCOUNT_FANOTIFY_GROUPS,
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UCOUNT_FANOTIFY_MARKS,
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#endif
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UCOUNT_RLIMIT_NPROC,
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UCOUNT_RLIMIT_MSGQUEUE,
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UCOUNT_RLIMIT_SIGPENDING,
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UCOUNT_RLIMIT_MEMLOCK,
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UCOUNT_COUNTS,
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};
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|
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#define MAX_PER_NAMESPACE_UCOUNTS UCOUNT_RLIMIT_NPROC
|
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|
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struct user_namespace {
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struct uid_gid_map uid_map;
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struct uid_gid_map gid_map;
|
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|
@ -92,23 +98,42 @@ struct user_namespace {
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struct ctl_table_header *sysctls;
|
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#endif
|
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struct ucounts *ucounts;
|
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int ucount_max[UCOUNT_COUNTS];
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long ucount_max[UCOUNT_COUNTS];
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} __randomize_layout;
|
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|
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struct ucounts {
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struct hlist_node node;
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struct user_namespace *ns;
|
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kuid_t uid;
|
||||
int count;
|
||||
atomic_t ucount[UCOUNT_COUNTS];
|
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atomic_t count;
|
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atomic_long_t ucount[UCOUNT_COUNTS];
|
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};
|
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|
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extern struct user_namespace init_user_ns;
|
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extern struct ucounts init_ucounts;
|
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|
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bool setup_userns_sysctls(struct user_namespace *ns);
|
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void retire_userns_sysctls(struct user_namespace *ns);
|
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struct ucounts *inc_ucount(struct user_namespace *ns, kuid_t uid, enum ucount_type type);
|
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void dec_ucount(struct ucounts *ucounts, enum ucount_type type);
|
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struct ucounts *alloc_ucounts(struct user_namespace *ns, kuid_t uid);
|
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struct ucounts * __must_check get_ucounts(struct ucounts *ucounts);
|
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void put_ucounts(struct ucounts *ucounts);
|
||||
|
||||
static inline long get_ucounts_value(struct ucounts *ucounts, enum ucount_type type)
|
||||
{
|
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return atomic_long_read(&ucounts->ucount[type]);
|
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}
|
||||
|
||||
long inc_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v);
|
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bool dec_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v);
|
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bool is_ucounts_overlimit(struct ucounts *ucounts, enum ucount_type type, unsigned long max);
|
||||
|
||||
static inline void set_rlimit_ucount_max(struct user_namespace *ns,
|
||||
enum ucount_type type, unsigned long max)
|
||||
{
|
||||
ns->ucount_max[type] = max <= LONG_MAX ? max : LONG_MAX;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_USER_NS
|
||||
|
||||
|
|
30
ipc/mqueue.c
30
ipc/mqueue.c
|
@ -144,7 +144,7 @@ struct mqueue_inode_info {
|
|||
struct pid *notify_owner;
|
||||
u32 notify_self_exec_id;
|
||||
struct user_namespace *notify_user_ns;
|
||||
struct user_struct *user; /* user who created, for accounting */
|
||||
struct ucounts *ucounts; /* user who created, for accounting */
|
||||
struct sock *notify_sock;
|
||||
struct sk_buff *notify_cookie;
|
||||
|
||||
|
@ -292,7 +292,6 @@ static struct inode *mqueue_get_inode(struct super_block *sb,
|
|||
struct ipc_namespace *ipc_ns, umode_t mode,
|
||||
struct mq_attr *attr)
|
||||
{
|
||||
struct user_struct *u = current_user();
|
||||
struct inode *inode;
|
||||
int ret = -ENOMEM;
|
||||
|
||||
|
@ -321,7 +320,7 @@ static struct inode *mqueue_get_inode(struct super_block *sb,
|
|||
info->notify_owner = NULL;
|
||||
info->notify_user_ns = NULL;
|
||||
info->qsize = 0;
|
||||
info->user = NULL; /* set when all is ok */
|
||||
info->ucounts = NULL; /* set when all is ok */
|
||||
info->msg_tree = RB_ROOT;
|
||||
info->msg_tree_rightmost = NULL;
|
||||
info->node_cache = NULL;
|
||||
|
@ -371,19 +370,23 @@ static struct inode *mqueue_get_inode(struct super_block *sb,
|
|||
if (mq_bytes + mq_treesize < mq_bytes)
|
||||
goto out_inode;
|
||||
mq_bytes += mq_treesize;
|
||||
info->ucounts = get_ucounts(current_ucounts());
|
||||
if (info->ucounts) {
|
||||
long msgqueue;
|
||||
|
||||
spin_lock(&mq_lock);
|
||||
if (u->mq_bytes + mq_bytes < u->mq_bytes ||
|
||||
u->mq_bytes + mq_bytes > rlimit(RLIMIT_MSGQUEUE)) {
|
||||
msgqueue = inc_rlimit_ucounts(info->ucounts, UCOUNT_RLIMIT_MSGQUEUE, mq_bytes);
|
||||
if (msgqueue == LONG_MAX || msgqueue > rlimit(RLIMIT_MSGQUEUE)) {
|
||||
dec_rlimit_ucounts(info->ucounts, UCOUNT_RLIMIT_MSGQUEUE, mq_bytes);
|
||||
spin_unlock(&mq_lock);
|
||||
put_ucounts(info->ucounts);
|
||||
info->ucounts = NULL;
|
||||
/* mqueue_evict_inode() releases info->messages */
|
||||
ret = -EMFILE;
|
||||
goto out_inode;
|
||||
}
|
||||
u->mq_bytes += mq_bytes;
|
||||
spin_unlock(&mq_lock);
|
||||
|
||||
/* all is ok */
|
||||
info->user = get_uid(u);
|
||||
}
|
||||
} else if (S_ISDIR(mode)) {
|
||||
inc_nlink(inode);
|
||||
/* Some things misbehave if size == 0 on a directory */
|
||||
|
@ -497,7 +500,6 @@ static void mqueue_free_inode(struct inode *inode)
|
|||
static void mqueue_evict_inode(struct inode *inode)
|
||||
{
|
||||
struct mqueue_inode_info *info;
|
||||
struct user_struct *user;
|
||||
struct ipc_namespace *ipc_ns;
|
||||
struct msg_msg *msg, *nmsg;
|
||||
LIST_HEAD(tmp_msg);
|
||||
|
@ -520,8 +522,7 @@ static void mqueue_evict_inode(struct inode *inode)
|
|||
free_msg(msg);
|
||||
}
|
||||
|
||||
user = info->user;
|
||||
if (user) {
|
||||
if (info->ucounts) {
|
||||
unsigned long mq_bytes, mq_treesize;
|
||||
|
||||
/* Total amount of bytes accounted for the mqueue */
|
||||
|
@ -533,7 +534,7 @@ static void mqueue_evict_inode(struct inode *inode)
|
|||
info->attr.mq_msgsize);
|
||||
|
||||
spin_lock(&mq_lock);
|
||||
user->mq_bytes -= mq_bytes;
|
||||
dec_rlimit_ucounts(info->ucounts, UCOUNT_RLIMIT_MSGQUEUE, mq_bytes);
|
||||
/*
|
||||
* get_ns_from_inode() ensures that the
|
||||
* (ipc_ns = sb->s_fs_info) is either a valid ipc_ns
|
||||
|
@ -543,7 +544,8 @@ static void mqueue_evict_inode(struct inode *inode)
|
|||
if (ipc_ns)
|
||||
ipc_ns->mq_queues_count--;
|
||||
spin_unlock(&mq_lock);
|
||||
free_uid(user);
|
||||
put_ucounts(info->ucounts);
|
||||
info->ucounts = NULL;
|
||||
}
|
||||
if (ipc_ns)
|
||||
put_ipc_ns(ipc_ns);
|
||||
|
|
26
ipc/shm.c
26
ipc/shm.c
|
@ -60,7 +60,7 @@ struct shmid_kernel /* private to the kernel */
|
|||
time64_t shm_ctim;
|
||||
struct pid *shm_cprid;
|
||||
struct pid *shm_lprid;
|
||||
struct user_struct *mlock_user;
|
||||
struct ucounts *mlock_ucounts;
|
||||
|
||||
/* The task created the shm object. NULL if the task is dead. */
|
||||
struct task_struct *shm_creator;
|
||||
|
@ -286,10 +286,10 @@ static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
|
|||
shm_rmid(ns, shp);
|
||||
shm_unlock(shp);
|
||||
if (!is_file_hugepages(shm_file))
|
||||
shmem_lock(shm_file, 0, shp->mlock_user);
|
||||
else if (shp->mlock_user)
|
||||
shmem_lock(shm_file, 0, shp->mlock_ucounts);
|
||||
else if (shp->mlock_ucounts)
|
||||
user_shm_unlock(i_size_read(file_inode(shm_file)),
|
||||
shp->mlock_user);
|
||||
shp->mlock_ucounts);
|
||||
fput(shm_file);
|
||||
ipc_update_pid(&shp->shm_cprid, NULL);
|
||||
ipc_update_pid(&shp->shm_lprid, NULL);
|
||||
|
@ -625,7 +625,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
|
|||
|
||||
shp->shm_perm.key = key;
|
||||
shp->shm_perm.mode = (shmflg & S_IRWXUGO);
|
||||
shp->mlock_user = NULL;
|
||||
shp->mlock_ucounts = NULL;
|
||||
|
||||
shp->shm_perm.security = NULL;
|
||||
error = security_shm_alloc(&shp->shm_perm);
|
||||
|
@ -650,7 +650,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
|
|||
if (shmflg & SHM_NORESERVE)
|
||||
acctflag = VM_NORESERVE;
|
||||
file = hugetlb_file_setup(name, hugesize, acctflag,
|
||||
&shp->mlock_user, HUGETLB_SHMFS_INODE,
|
||||
&shp->mlock_ucounts, HUGETLB_SHMFS_INODE,
|
||||
(shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK);
|
||||
} else {
|
||||
/*
|
||||
|
@ -698,8 +698,8 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
|
|||
no_id:
|
||||
ipc_update_pid(&shp->shm_cprid, NULL);
|
||||
ipc_update_pid(&shp->shm_lprid, NULL);
|
||||
if (is_file_hugepages(file) && shp->mlock_user)
|
||||
user_shm_unlock(size, shp->mlock_user);
|
||||
if (is_file_hugepages(file) && shp->mlock_ucounts)
|
||||
user_shm_unlock(size, shp->mlock_ucounts);
|
||||
fput(file);
|
||||
ipc_rcu_putref(&shp->shm_perm, shm_rcu_free);
|
||||
return error;
|
||||
|
@ -1105,12 +1105,12 @@ static int shmctl_do_lock(struct ipc_namespace *ns, int shmid, int cmd)
|
|||
goto out_unlock0;
|
||||
|
||||
if (cmd == SHM_LOCK) {
|
||||
struct user_struct *user = current_user();
|
||||
struct ucounts *ucounts = current_ucounts();
|
||||
|
||||
err = shmem_lock(shm_file, 1, user);
|
||||
err = shmem_lock(shm_file, 1, ucounts);
|
||||
if (!err && !(shp->shm_perm.mode & SHM_LOCKED)) {
|
||||
shp->shm_perm.mode |= SHM_LOCKED;
|
||||
shp->mlock_user = user;
|
||||
shp->mlock_ucounts = ucounts;
|
||||
}
|
||||
goto out_unlock0;
|
||||
}
|
||||
|
@ -1118,9 +1118,9 @@ static int shmctl_do_lock(struct ipc_namespace *ns, int shmid, int cmd)
|
|||
/* SHM_UNLOCK */
|
||||
if (!(shp->shm_perm.mode & SHM_LOCKED))
|
||||
goto out_unlock0;
|
||||
shmem_lock(shm_file, 0, shp->mlock_user);
|
||||
shmem_lock(shm_file, 0, shp->mlock_ucounts);
|
||||
shp->shm_perm.mode &= ~SHM_LOCKED;
|
||||
shp->mlock_user = NULL;
|
||||
shp->mlock_ucounts = NULL;
|
||||
get_file(shm_file);
|
||||
ipc_unlock_object(&shp->shm_perm);
|
||||
rcu_read_unlock();
|
||||
|
|
|
@ -60,6 +60,7 @@ struct cred init_cred = {
|
|||
.user = INIT_USER,
|
||||
.user_ns = &init_user_ns,
|
||||
.group_info = &init_groups,
|
||||
.ucounts = &init_ucounts,
|
||||
};
|
||||
|
||||
static inline void set_cred_subscribers(struct cred *cred, int n)
|
||||
|
@ -119,6 +120,8 @@ static void put_cred_rcu(struct rcu_head *rcu)
|
|||
if (cred->group_info)
|
||||
put_group_info(cred->group_info);
|
||||
free_uid(cred->user);
|
||||
if (cred->ucounts)
|
||||
put_ucounts(cred->ucounts);
|
||||
put_user_ns(cred->user_ns);
|
||||
kmem_cache_free(cred_jar, cred);
|
||||
}
|
||||
|
@ -222,6 +225,7 @@ struct cred *cred_alloc_blank(void)
|
|||
#ifdef CONFIG_DEBUG_CREDENTIALS
|
||||
new->magic = CRED_MAGIC;
|
||||
#endif
|
||||
new->ucounts = get_ucounts(&init_ucounts);
|
||||
|
||||
if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0)
|
||||
goto error;
|
||||
|
@ -284,6 +288,11 @@ struct cred *prepare_creds(void)
|
|||
|
||||
if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
|
||||
goto error;
|
||||
|
||||
new->ucounts = get_ucounts(new->ucounts);
|
||||
if (!new->ucounts)
|
||||
goto error;
|
||||
|
||||
validate_creds(new);
|
||||
return new;
|
||||
|
||||
|
@ -351,7 +360,7 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
|
|||
kdebug("share_creds(%p{%d,%d})",
|
||||
p->cred, atomic_read(&p->cred->usage),
|
||||
read_cred_subscribers(p->cred));
|
||||
atomic_inc(&p->cred->user->processes);
|
||||
inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
@ -363,6 +372,9 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
|
|||
ret = create_user_ns(new);
|
||||
if (ret < 0)
|
||||
goto error_put;
|
||||
ret = set_cred_ucounts(new);
|
||||
if (ret < 0)
|
||||
goto error_put;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_KEYS
|
||||
|
@ -384,8 +396,8 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
|
|||
}
|
||||
#endif
|
||||
|
||||
atomic_inc(&new->user->processes);
|
||||
p->cred = p->real_cred = get_cred(new);
|
||||
inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
|
||||
alter_cred_subscribers(new, 2);
|
||||
validate_creds(new);
|
||||
return 0;
|
||||
|
@ -485,12 +497,12 @@ int commit_creds(struct cred *new)
|
|||
* in set_user().
|
||||
*/
|
||||
alter_cred_subscribers(new, 2);
|
||||
if (new->user != old->user)
|
||||
atomic_inc(&new->user->processes);
|
||||
if (new->user != old->user || new->user_ns != old->user_ns)
|
||||
inc_rlimit_ucounts(new->ucounts, UCOUNT_RLIMIT_NPROC, 1);
|
||||
rcu_assign_pointer(task->real_cred, new);
|
||||
rcu_assign_pointer(task->cred, new);
|
||||
if (new->user != old->user)
|
||||
atomic_dec(&old->user->processes);
|
||||
dec_rlimit_ucounts(old->ucounts, UCOUNT_RLIMIT_NPROC, 1);
|
||||
alter_cred_subscribers(old, -2);
|
||||
|
||||
/* send notifications */
|
||||
|
@ -653,6 +665,31 @@ int cred_fscmp(const struct cred *a, const struct cred *b)
|
|||
}
|
||||
EXPORT_SYMBOL(cred_fscmp);
|
||||
|
||||
int set_cred_ucounts(struct cred *new)
|
||||
{
|
||||
struct task_struct *task = current;
|
||||
const struct cred *old = task->real_cred;
|
||||
struct ucounts *old_ucounts = new->ucounts;
|
||||
|
||||
if (new->user == old->user && new->user_ns == old->user_ns)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* This optimization is needed because alloc_ucounts() uses locks
|
||||
* for table lookups.
|
||||
*/
|
||||
if (old_ucounts && old_ucounts->ns == new->user_ns && uid_eq(old_ucounts->uid, new->euid))
|
||||
return 0;
|
||||
|
||||
if (!(new->ucounts = alloc_ucounts(new->user_ns, new->euid)))
|
||||
return -EAGAIN;
|
||||
|
||||
if (old_ucounts)
|
||||
put_ucounts(old_ucounts);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* initialise the credentials stuff
|
||||
*/
|
||||
|
@ -719,6 +756,10 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
|
|||
if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
|
||||
goto error;
|
||||
|
||||
new->ucounts = get_ucounts(new->ucounts);
|
||||
if (!new->ucounts)
|
||||
goto error;
|
||||
|
||||
put_cred(old);
|
||||
validate_creds(new);
|
||||
return new;
|
||||
|
|
|
@ -188,7 +188,7 @@ repeat:
|
|||
/* don't need to get the RCU readlock here - the process is dead and
|
||||
* can't be modifying its own credentials. But shut RCU-lockdep up */
|
||||
rcu_read_lock();
|
||||
atomic_dec(&__task_cred(p)->user->processes);
|
||||
dec_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
|
||||
rcu_read_unlock();
|
||||
|
||||
cgroup_release(p);
|
||||
|
|
|
@ -825,9 +825,14 @@ void __init fork_init(void)
|
|||
init_task.signal->rlim[RLIMIT_SIGPENDING] =
|
||||
init_task.signal->rlim[RLIMIT_NPROC];
|
||||
|
||||
for (i = 0; i < UCOUNT_COUNTS; i++)
|
||||
for (i = 0; i < MAX_PER_NAMESPACE_UCOUNTS; i++)
|
||||
init_user_ns.ucount_max[i] = max_threads/2;
|
||||
|
||||
set_rlimit_ucount_max(&init_user_ns, UCOUNT_RLIMIT_NPROC, task_rlimit(&init_task, RLIMIT_NPROC));
|
||||
set_rlimit_ucount_max(&init_user_ns, UCOUNT_RLIMIT_MSGQUEUE, task_rlimit(&init_task, RLIMIT_MSGQUEUE));
|
||||
set_rlimit_ucount_max(&init_user_ns, UCOUNT_RLIMIT_SIGPENDING, task_rlimit(&init_task, RLIMIT_SIGPENDING));
|
||||
set_rlimit_ucount_max(&init_user_ns, UCOUNT_RLIMIT_MEMLOCK, task_rlimit(&init_task, RLIMIT_MEMLOCK));
|
||||
|
||||
#ifdef CONFIG_VMAP_STACK
|
||||
cpuhp_setup_state(CPUHP_BP_PREPARE_DYN, "fork:vm_stack_cache",
|
||||
NULL, free_vm_stack_cache);
|
||||
|
@ -1978,8 +1983,7 @@ static __latent_entropy struct task_struct *copy_process(
|
|||
DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
|
||||
#endif
|
||||
retval = -EAGAIN;
|
||||
if (atomic_read(&p->real_cred->user->processes) >=
|
||||
task_rlimit(p, RLIMIT_NPROC)) {
|
||||
if (is_ucounts_overlimit(task_ucounts(p), UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC))) {
|
||||
if (p->real_cred->user != INIT_USER &&
|
||||
!capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN))
|
||||
goto bad_fork_free;
|
||||
|
@ -2388,7 +2392,7 @@ bad_fork_cleanup_threadgroup_lock:
|
|||
#endif
|
||||
delayacct_tsk_free(p);
|
||||
bad_fork_cleanup_count:
|
||||
atomic_dec(&p->cred->user->processes);
|
||||
dec_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
|
||||
exit_creds(p);
|
||||
bad_fork_free:
|
||||
WRITE_ONCE(p->__state, TASK_DEAD);
|
||||
|
@ -3001,6 +3005,12 @@ int ksys_unshare(unsigned long unshare_flags)
|
|||
if (err)
|
||||
goto bad_unshare_cleanup_cred;
|
||||
|
||||
if (new_cred) {
|
||||
err = set_cred_ucounts(new_cred);
|
||||
if (err)
|
||||
goto bad_unshare_cleanup_cred;
|
||||
}
|
||||
|
||||
if (new_fs || new_fd || do_sysvsem || new_cred || new_nsproxy) {
|
||||
if (do_sysvsem) {
|
||||
/*
|
||||
|
|
|
@ -412,8 +412,8 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags,
|
|||
int override_rlimit, const unsigned int sigqueue_flags)
|
||||
{
|
||||
struct sigqueue *q = NULL;
|
||||
struct user_struct *user;
|
||||
int sigpending;
|
||||
struct ucounts *ucounts = NULL;
|
||||
long sigpending;
|
||||
|
||||
/*
|
||||
* Protect access to @t credentials. This can go away when all
|
||||
|
@ -424,27 +424,26 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags,
|
|||
* changes from/to zero.
|
||||
*/
|
||||
rcu_read_lock();
|
||||
user = __task_cred(t)->user;
|
||||
sigpending = atomic_inc_return(&user->sigpending);
|
||||
ucounts = task_ucounts(t);
|
||||
sigpending = inc_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_SIGPENDING, 1);
|
||||
if (sigpending == 1)
|
||||
get_uid(user);
|
||||
ucounts = get_ucounts(ucounts);
|
||||
rcu_read_unlock();
|
||||
|
||||
if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
|
||||
if (override_rlimit || (sigpending < LONG_MAX && sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
|
||||
q = kmem_cache_alloc(sigqueue_cachep, gfp_flags);
|
||||
} else {
|
||||
print_dropped_signal(sig);
|
||||
}
|
||||
|
||||
if (unlikely(q == NULL)) {
|
||||
if (atomic_dec_and_test(&user->sigpending))
|
||||
free_uid(user);
|
||||
if (ucounts && dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_SIGPENDING, 1))
|
||||
put_ucounts(ucounts);
|
||||
} else {
|
||||
INIT_LIST_HEAD(&q->list);
|
||||
q->flags = sigqueue_flags;
|
||||
q->user = user;
|
||||
q->ucounts = ucounts;
|
||||
}
|
||||
|
||||
return q;
|
||||
}
|
||||
|
||||
|
@ -452,8 +451,10 @@ static void __sigqueue_free(struct sigqueue *q)
|
|||
{
|
||||
if (q->flags & SIGQUEUE_PREALLOC)
|
||||
return;
|
||||
if (atomic_dec_and_test(&q->user->sigpending))
|
||||
free_uid(q->user);
|
||||
if (q->ucounts && dec_rlimit_ucounts(q->ucounts, UCOUNT_RLIMIT_SIGPENDING, 1)) {
|
||||
put_ucounts(q->ucounts);
|
||||
q->ucounts = NULL;
|
||||
}
|
||||
kmem_cache_free(sigqueue_cachep, q);
|
||||
}
|
||||
|
||||
|
|
14
kernel/sys.c
14
kernel/sys.c
|
@ -479,7 +479,7 @@ static int set_user(struct cred *new)
|
|||
* for programs doing set*uid()+execve() by harmlessly deferring the
|
||||
* failure to the execve() stage.
|
||||
*/
|
||||
if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
|
||||
if (is_ucounts_overlimit(new->ucounts, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC)) &&
|
||||
new_user != INIT_USER)
|
||||
current->flags |= PF_NPROC_EXCEEDED;
|
||||
else
|
||||
|
@ -558,6 +558,10 @@ long __sys_setreuid(uid_t ruid, uid_t euid)
|
|||
if (retval < 0)
|
||||
goto error;
|
||||
|
||||
retval = set_cred_ucounts(new);
|
||||
if (retval < 0)
|
||||
goto error;
|
||||
|
||||
return commit_creds(new);
|
||||
|
||||
error:
|
||||
|
@ -616,6 +620,10 @@ long __sys_setuid(uid_t uid)
|
|||
if (retval < 0)
|
||||
goto error;
|
||||
|
||||
retval = set_cred_ucounts(new);
|
||||
if (retval < 0)
|
||||
goto error;
|
||||
|
||||
return commit_creds(new);
|
||||
|
||||
error:
|
||||
|
@ -691,6 +699,10 @@ long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
|
|||
if (retval < 0)
|
||||
goto error;
|
||||
|
||||
retval = set_cred_ucounts(new);
|
||||
if (retval < 0)
|
||||
goto error;
|
||||
|
||||
return commit_creds(new);
|
||||
|
||||
error:
|
||||
|
|
114
kernel/ucount.c
114
kernel/ucount.c
|
@ -8,6 +8,12 @@
|
|||
#include <linux/kmemleak.h>
|
||||
#include <linux/user_namespace.h>
|
||||
|
||||
struct ucounts init_ucounts = {
|
||||
.ns = &init_user_ns,
|
||||
.uid = GLOBAL_ROOT_UID,
|
||||
.count = ATOMIC_INIT(1),
|
||||
};
|
||||
|
||||
#define UCOUNTS_HASHTABLE_BITS 10
|
||||
static struct hlist_head ucounts_hashtable[(1 << UCOUNTS_HASHTABLE_BITS)];
|
||||
static DEFINE_SPINLOCK(ucounts_lock);
|
||||
|
@ -78,6 +84,10 @@ static struct ctl_table user_table[] = {
|
|||
UCOUNT_ENTRY("max_fanotify_groups"),
|
||||
UCOUNT_ENTRY("max_fanotify_marks"),
|
||||
#endif
|
||||
{ },
|
||||
{ },
|
||||
{ },
|
||||
{ },
|
||||
{ }
|
||||
};
|
||||
#endif /* CONFIG_SYSCTL */
|
||||
|
@ -129,7 +139,24 @@ static struct ucounts *find_ucounts(struct user_namespace *ns, kuid_t uid, struc
|
|||
return NULL;
|
||||
}
|
||||
|
||||
static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
|
||||
static void hlist_add_ucounts(struct ucounts *ucounts)
|
||||
{
|
||||
struct hlist_head *hashent = ucounts_hashentry(ucounts->ns, ucounts->uid);
|
||||
spin_lock_irq(&ucounts_lock);
|
||||
hlist_add_head(&ucounts->node, hashent);
|
||||
spin_unlock_irq(&ucounts_lock);
|
||||
}
|
||||
|
||||
struct ucounts *get_ucounts(struct ucounts *ucounts)
|
||||
{
|
||||
if (ucounts && atomic_add_negative(1, &ucounts->count)) {
|
||||
put_ucounts(ucounts);
|
||||
ucounts = NULL;
|
||||
}
|
||||
return ucounts;
|
||||
}
|
||||
|
||||
struct ucounts *alloc_ucounts(struct user_namespace *ns, kuid_t uid)
|
||||
{
|
||||
struct hlist_head *hashent = ucounts_hashentry(ns, uid);
|
||||
struct ucounts *ucounts, *new;
|
||||
|
@ -145,7 +172,7 @@ static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
|
|||
|
||||
new->ns = ns;
|
||||
new->uid = uid;
|
||||
new->count = 0;
|
||||
atomic_set(&new->count, 1);
|
||||
|
||||
spin_lock_irq(&ucounts_lock);
|
||||
ucounts = find_ucounts(ns, uid, hashent);
|
||||
|
@ -153,40 +180,35 @@ static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
|
|||
kfree(new);
|
||||
} else {
|
||||
hlist_add_head(&new->node, hashent);
|
||||
ucounts = new;
|
||||
}
|
||||
}
|
||||
if (ucounts->count == INT_MAX)
|
||||
ucounts = NULL;
|
||||
else
|
||||
ucounts->count += 1;
|
||||
spin_unlock_irq(&ucounts_lock);
|
||||
return new;
|
||||
}
|
||||
}
|
||||
spin_unlock_irq(&ucounts_lock);
|
||||
ucounts = get_ucounts(ucounts);
|
||||
return ucounts;
|
||||
}
|
||||
|
||||
static void put_ucounts(struct ucounts *ucounts)
|
||||
void put_ucounts(struct ucounts *ucounts)
|
||||
{
|
||||
unsigned long flags;
|
||||
|
||||
if (atomic_dec_and_test(&ucounts->count)) {
|
||||
spin_lock_irqsave(&ucounts_lock, flags);
|
||||
ucounts->count -= 1;
|
||||
if (!ucounts->count)
|
||||
hlist_del_init(&ucounts->node);
|
||||
else
|
||||
ucounts = NULL;
|
||||
spin_unlock_irqrestore(&ucounts_lock, flags);
|
||||
|
||||
kfree(ucounts);
|
||||
}
|
||||
}
|
||||
|
||||
static inline bool atomic_inc_below(atomic_t *v, int u)
|
||||
static inline bool atomic_long_inc_below(atomic_long_t *v, int u)
|
||||
{
|
||||
int c, old;
|
||||
c = atomic_read(v);
|
||||
long c, old;
|
||||
c = atomic_long_read(v);
|
||||
for (;;) {
|
||||
if (unlikely(c >= u))
|
||||
return false;
|
||||
old = atomic_cmpxchg(v, c, c+1);
|
||||
old = atomic_long_cmpxchg(v, c, c+1);
|
||||
if (likely(old == c))
|
||||
return true;
|
||||
c = old;
|
||||
|
@ -198,19 +220,19 @@ struct ucounts *inc_ucount(struct user_namespace *ns, kuid_t uid,
|
|||
{
|
||||
struct ucounts *ucounts, *iter, *bad;
|
||||
struct user_namespace *tns;
|
||||
ucounts = get_ucounts(ns, uid);
|
||||
ucounts = alloc_ucounts(ns, uid);
|
||||
for (iter = ucounts; iter; iter = tns->ucounts) {
|
||||
int max;
|
||||
long max;
|
||||
tns = iter->ns;
|
||||
max = READ_ONCE(tns->ucount_max[type]);
|
||||
if (!atomic_inc_below(&iter->ucount[type], max))
|
||||
if (!atomic_long_inc_below(&iter->ucount[type], max))
|
||||
goto fail;
|
||||
}
|
||||
return ucounts;
|
||||
fail:
|
||||
bad = iter;
|
||||
for (iter = ucounts; iter != bad; iter = iter->ns->ucounts)
|
||||
atomic_dec(&iter->ucount[type]);
|
||||
atomic_long_dec(&iter->ucount[type]);
|
||||
|
||||
put_ucounts(ucounts);
|
||||
return NULL;
|
||||
|
@ -220,12 +242,54 @@ void dec_ucount(struct ucounts *ucounts, enum ucount_type type)
|
|||
{
|
||||
struct ucounts *iter;
|
||||
for (iter = ucounts; iter; iter = iter->ns->ucounts) {
|
||||
int dec = atomic_dec_if_positive(&iter->ucount[type]);
|
||||
long dec = atomic_long_dec_if_positive(&iter->ucount[type]);
|
||||
WARN_ON_ONCE(dec < 0);
|
||||
}
|
||||
put_ucounts(ucounts);
|
||||
}
|
||||
|
||||
long inc_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v)
|
||||
{
|
||||
struct ucounts *iter;
|
||||
long ret = 0;
|
||||
|
||||
for (iter = ucounts; iter; iter = iter->ns->ucounts) {
|
||||
long max = READ_ONCE(iter->ns->ucount_max[type]);
|
||||
long new = atomic_long_add_return(v, &iter->ucount[type]);
|
||||
if (new < 0 || new > max)
|
||||
ret = LONG_MAX;
|
||||
else if (iter == ucounts)
|
||||
ret = new;
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
bool dec_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v)
|
||||
{
|
||||
struct ucounts *iter;
|
||||
long new = -1; /* Silence compiler warning */
|
||||
for (iter = ucounts; iter; iter = iter->ns->ucounts) {
|
||||
long dec = atomic_long_add_return(-v, &iter->ucount[type]);
|
||||
WARN_ON_ONCE(dec < 0);
|
||||
if (iter == ucounts)
|
||||
new = dec;
|
||||
}
|
||||
return (new == 0);
|
||||
}
|
||||
|
||||
bool is_ucounts_overlimit(struct ucounts *ucounts, enum ucount_type type, unsigned long max)
|
||||
{
|
||||
struct ucounts *iter;
|
||||
if (get_ucounts_value(ucounts, type) > max)
|
||||
return true;
|
||||
for (iter = ucounts; iter; iter = iter->ns->ucounts) {
|
||||
max = READ_ONCE(iter->ns->ucount_max[type]);
|
||||
if (get_ucounts_value(iter, type) > max)
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
static __init int user_namespace_sysctl_init(void)
|
||||
{
|
||||
#ifdef CONFIG_SYSCTL
|
||||
|
@ -241,6 +305,8 @@ static __init int user_namespace_sysctl_init(void)
|
|||
BUG_ON(!user_header);
|
||||
BUG_ON(!setup_userns_sysctls(&init_user_ns));
|
||||
#endif
|
||||
hlist_add_ucounts(&init_ucounts);
|
||||
inc_rlimit_ucounts(&init_ucounts, UCOUNT_RLIMIT_NPROC, 1);
|
||||
return 0;
|
||||
}
|
||||
subsys_initcall(user_namespace_sysctl_init);
|
||||
|
|
|
@ -98,9 +98,6 @@ static DEFINE_SPINLOCK(uidhash_lock);
|
|||
/* root_user.__count is 1, for init task cred */
|
||||
struct user_struct root_user = {
|
||||
.__count = REFCOUNT_INIT(1),
|
||||
.processes = ATOMIC_INIT(1),
|
||||
.sigpending = ATOMIC_INIT(0),
|
||||
.locked_shm = 0,
|
||||
.uid = GLOBAL_ROOT_UID,
|
||||
.ratelimit = RATELIMIT_STATE_INIT(root_user.ratelimit, 0, 0),
|
||||
};
|
||||
|
|
|
@ -119,9 +119,13 @@ int create_user_ns(struct cred *new)
|
|||
ns->owner = owner;
|
||||
ns->group = group;
|
||||
INIT_WORK(&ns->work, free_user_ns);
|
||||
for (i = 0; i < UCOUNT_COUNTS; i++) {
|
||||
for (i = 0; i < MAX_PER_NAMESPACE_UCOUNTS; i++) {
|
||||
ns->ucount_max[i] = INT_MAX;
|
||||
}
|
||||
set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC));
|
||||
set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_MSGQUEUE, rlimit(RLIMIT_MSGQUEUE));
|
||||
set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_SIGPENDING, rlimit(RLIMIT_SIGPENDING));
|
||||
set_rlimit_ucount_max(ns, UCOUNT_RLIMIT_MEMLOCK, rlimit(RLIMIT_MEMLOCK));
|
||||
ns->ucounts = ucounts;
|
||||
|
||||
/* Inherit USERNS_SETGROUPS_ALLOWED from our parent */
|
||||
|
@ -1340,6 +1344,9 @@ static int userns_install(struct nsset *nsset, struct ns_common *ns)
|
|||
put_user_ns(cred->user_ns);
|
||||
set_cred_user_ns(cred, get_user_ns(user_ns));
|
||||
|
||||
if (set_cred_ucounts(cred) < 0)
|
||||
return -EINVAL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
|
|
@ -297,9 +297,9 @@ SYSCALL_DEFINE2(memfd_create,
|
|||
}
|
||||
|
||||
if (flags & MFD_HUGETLB) {
|
||||
struct user_struct *user = NULL;
|
||||
struct ucounts *ucounts = NULL;
|
||||
|
||||
file = hugetlb_file_setup(name, 0, VM_NORESERVE, &user,
|
||||
file = hugetlb_file_setup(name, 0, VM_NORESERVE, &ucounts,
|
||||
HUGETLB_ANONHUGE_INODE,
|
||||
(flags >> MFD_HUGE_SHIFT) &
|
||||
MFD_HUGE_MASK);
|
||||
|
|
22
mm/mlock.c
22
mm/mlock.c
|
@ -817,9 +817,10 @@ SYSCALL_DEFINE0(munlockall)
|
|||
*/
|
||||
static DEFINE_SPINLOCK(shmlock_user_lock);
|
||||
|
||||
int user_shm_lock(size_t size, struct user_struct *user)
|
||||
int user_shm_lock(size_t size, struct ucounts *ucounts)
|
||||
{
|
||||
unsigned long lock_limit, locked;
|
||||
long memlock;
|
||||
int allowed = 0;
|
||||
|
||||
locked = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
||||
|
@ -828,21 +829,26 @@ int user_shm_lock(size_t size, struct user_struct *user)
|
|||
allowed = 1;
|
||||
lock_limit >>= PAGE_SHIFT;
|
||||
spin_lock(&shmlock_user_lock);
|
||||
if (!allowed &&
|
||||
locked + user->locked_shm > lock_limit && !capable(CAP_IPC_LOCK))
|
||||
memlock = inc_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked);
|
||||
|
||||
if (!allowed && (memlock == LONG_MAX || memlock > lock_limit) && !capable(CAP_IPC_LOCK)) {
|
||||
dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked);
|
||||
goto out;
|
||||
get_uid(user);
|
||||
user->locked_shm += locked;
|
||||
}
|
||||
if (!get_ucounts(ucounts)) {
|
||||
dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked);
|
||||
goto out;
|
||||
}
|
||||
allowed = 1;
|
||||
out:
|
||||
spin_unlock(&shmlock_user_lock);
|
||||
return allowed;
|
||||
}
|
||||
|
||||
void user_shm_unlock(size_t size, struct user_struct *user)
|
||||
void user_shm_unlock(size_t size, struct ucounts *ucounts)
|
||||
{
|
||||
spin_lock(&shmlock_user_lock);
|
||||
user->locked_shm -= (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
||||
dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, (size + PAGE_SIZE - 1) >> PAGE_SHIFT);
|
||||
spin_unlock(&shmlock_user_lock);
|
||||
free_uid(user);
|
||||
put_ucounts(ucounts);
|
||||
}
|
||||
|
|
|
@ -1611,7 +1611,7 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
|
|||
goto out_fput;
|
||||
}
|
||||
} else if (flags & MAP_HUGETLB) {
|
||||
struct user_struct *user = NULL;
|
||||
struct ucounts *ucounts = NULL;
|
||||
struct hstate *hs;
|
||||
|
||||
hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
|
||||
|
@ -1627,7 +1627,7 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
|
|||
*/
|
||||
file = hugetlb_file_setup(HUGETLB_ANON_FILE, len,
|
||||
VM_NORESERVE,
|
||||
&user, HUGETLB_ANONHUGE_INODE,
|
||||
&ucounts, HUGETLB_ANONHUGE_INODE,
|
||||
(flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
|
||||
if (IS_ERR(file))
|
||||
return PTR_ERR(file);
|
||||
|
|
10
mm/shmem.c
10
mm/shmem.c
|
@ -2227,7 +2227,7 @@ static struct mempolicy *shmem_get_policy(struct vm_area_struct *vma,
|
|||
}
|
||||
#endif
|
||||
|
||||
int shmem_lock(struct file *file, int lock, struct user_struct *user)
|
||||
int shmem_lock(struct file *file, int lock, struct ucounts *ucounts)
|
||||
{
|
||||
struct inode *inode = file_inode(file);
|
||||
struct shmem_inode_info *info = SHMEM_I(inode);
|
||||
|
@ -2239,13 +2239,13 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
|
|||
* no serialization needed when called from shm_destroy().
|
||||
*/
|
||||
if (lock && !(info->flags & VM_LOCKED)) {
|
||||
if (!user_shm_lock(inode->i_size, user))
|
||||
if (!user_shm_lock(inode->i_size, ucounts))
|
||||
goto out_nomem;
|
||||
info->flags |= VM_LOCKED;
|
||||
mapping_set_unevictable(file->f_mapping);
|
||||
}
|
||||
if (!lock && (info->flags & VM_LOCKED) && user) {
|
||||
user_shm_unlock(inode->i_size, user);
|
||||
if (!lock && (info->flags & VM_LOCKED) && ucounts) {
|
||||
user_shm_unlock(inode->i_size, ucounts);
|
||||
info->flags &= ~VM_LOCKED;
|
||||
mapping_clear_unevictable(file->f_mapping);
|
||||
}
|
||||
|
@ -4092,7 +4092,7 @@ int shmem_unuse(unsigned int type, bool frontswap,
|
|||
return 0;
|
||||
}
|
||||
|
||||
int shmem_lock(struct file *file, int lock, struct user_struct *user)
|
||||
int shmem_lock(struct file *file, int lock, struct ucounts *ucounts)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
|
|
@ -49,6 +49,7 @@ TARGETS += proc
|
|||
TARGETS += pstore
|
||||
TARGETS += ptrace
|
||||
TARGETS += openat2
|
||||
TARGETS += rlimits
|
||||
TARGETS += rseq
|
||||
TARGETS += rtc
|
||||
TARGETS += seccomp
|
||||
|
|
|
@ -0,0 +1,2 @@
|
|||
# SPDX-License-Identifier: GPL-2.0-only
|
||||
rlimits-per-userns
|
|
@ -0,0 +1,6 @@
|
|||
# SPDX-License-Identifier: GPL-2.0-or-later
|
||||
|
||||
CFLAGS += -Wall -O2 -g
|
||||
TEST_GEN_PROGS := rlimits-per-userns
|
||||
|
||||
include ../lib.mk
|
|
@ -0,0 +1 @@
|
|||
CONFIG_USER_NS=y
|
|
@ -0,0 +1,161 @@
|
|||
// SPDX-License-Identifier: GPL-2.0-or-later
|
||||
/*
|
||||
* Author: Alexey Gladkov <gladkov.alexey@gmail.com>
|
||||
*/
|
||||
#define _GNU_SOURCE
|
||||
#include <sys/types.h>
|
||||
#include <sys/wait.h>
|
||||
#include <sys/time.h>
|
||||
#include <sys/resource.h>
|
||||
#include <sys/prctl.h>
|
||||
#include <sys/stat.h>
|
||||
|
||||
#include <unistd.h>
|
||||
#include <stdlib.h>
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
#include <sched.h>
|
||||
#include <signal.h>
|
||||
#include <limits.h>
|
||||
#include <fcntl.h>
|
||||
#include <errno.h>
|
||||
#include <err.h>
|
||||
|
||||
#define NR_CHILDS 2
|
||||
|
||||
static char *service_prog;
|
||||
static uid_t user = 60000;
|
||||
static uid_t group = 60000;
|
||||
|
||||
static void setrlimit_nproc(rlim_t n)
|
||||
{
|
||||
pid_t pid = getpid();
|
||||
struct rlimit limit = {
|
||||
.rlim_cur = n,
|
||||
.rlim_max = n
|
||||
};
|
||||
|
||||
warnx("(pid=%d): Setting RLIMIT_NPROC=%ld", pid, n);
|
||||
|
||||
if (setrlimit(RLIMIT_NPROC, &limit) < 0)
|
||||
err(EXIT_FAILURE, "(pid=%d): setrlimit(RLIMIT_NPROC)", pid);
|
||||
}
|
||||
|
||||
static pid_t fork_child(void)
|
||||
{
|
||||
pid_t pid = fork();
|
||||
|
||||
if (pid < 0)
|
||||
err(EXIT_FAILURE, "fork");
|
||||
|
||||
if (pid > 0)
|
||||
return pid;
|
||||
|
||||
pid = getpid();
|
||||
|
||||
warnx("(pid=%d): New process starting ...", pid);
|
||||
|
||||
if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0)
|
||||
err(EXIT_FAILURE, "(pid=%d): prctl(PR_SET_PDEATHSIG)", pid);
|
||||
|
||||
signal(SIGUSR1, SIG_DFL);
|
||||
|
||||
warnx("(pid=%d): Changing to uid=%d, gid=%d", pid, user, group);
|
||||
|
||||
if (setgid(group) < 0)
|
||||
err(EXIT_FAILURE, "(pid=%d): setgid(%d)", pid, group);
|
||||
if (setuid(user) < 0)
|
||||
err(EXIT_FAILURE, "(pid=%d): setuid(%d)", pid, user);
|
||||
|
||||
warnx("(pid=%d): Service running ...", pid);
|
||||
|
||||
warnx("(pid=%d): Unshare user namespace", pid);
|
||||
if (unshare(CLONE_NEWUSER) < 0)
|
||||
err(EXIT_FAILURE, "unshare(CLONE_NEWUSER)");
|
||||
|
||||
char *const argv[] = { "service", NULL };
|
||||
char *const envp[] = { "I_AM_SERVICE=1", NULL };
|
||||
|
||||
warnx("(pid=%d): Executing real service ...", pid);
|
||||
|
||||
execve(service_prog, argv, envp);
|
||||
err(EXIT_FAILURE, "(pid=%d): execve", pid);
|
||||
}
|
||||
|
||||
int main(int argc, char **argv)
|
||||
{
|
||||
size_t i;
|
||||
pid_t child[NR_CHILDS];
|
||||
int wstatus[NR_CHILDS];
|
||||
int childs = NR_CHILDS;
|
||||
pid_t pid;
|
||||
|
||||
if (getenv("I_AM_SERVICE")) {
|
||||
pause();
|
||||
exit(EXIT_SUCCESS);
|
||||
}
|
||||
|
||||
service_prog = argv[0];
|
||||
pid = getpid();
|
||||
|
||||
warnx("(pid=%d) Starting testcase", pid);
|
||||
|
||||
/*
|
||||
* This rlimit is not a problem for root because it can be exceeded.
|
||||
*/
|
||||
setrlimit_nproc(1);
|
||||
|
||||
for (i = 0; i < NR_CHILDS; i++) {
|
||||
child[i] = fork_child();
|
||||
wstatus[i] = 0;
|
||||
usleep(250000);
|
||||
}
|
||||
|
||||
while (1) {
|
||||
for (i = 0; i < NR_CHILDS; i++) {
|
||||
if (child[i] <= 0)
|
||||
continue;
|
||||
|
||||
errno = 0;
|
||||
pid_t ret = waitpid(child[i], &wstatus[i], WNOHANG);
|
||||
|
||||
if (!ret || (!WIFEXITED(wstatus[i]) && !WIFSIGNALED(wstatus[i])))
|
||||
continue;
|
||||
|
||||
if (ret < 0 && errno != ECHILD)
|
||||
warn("(pid=%d): waitpid(%d)", pid, child[i]);
|
||||
|
||||
child[i] *= -1;
|
||||
childs -= 1;
|
||||
}
|
||||
|
||||
if (!childs)
|
||||
break;
|
||||
|
||||
usleep(250000);
|
||||
|
||||
for (i = 0; i < NR_CHILDS; i++) {
|
||||
if (child[i] <= 0)
|
||||
continue;
|
||||
kill(child[i], SIGUSR1);
|
||||
}
|
||||
}
|
||||
|
||||
for (i = 0; i < NR_CHILDS; i++) {
|
||||
if (WIFEXITED(wstatus[i]))
|
||||
warnx("(pid=%d): pid %d exited, status=%d",
|
||||
pid, -child[i], WEXITSTATUS(wstatus[i]));
|
||||
else if (WIFSIGNALED(wstatus[i]))
|
||||
warnx("(pid=%d): pid %d killed by signal %d",
|
||||
pid, -child[i], WTERMSIG(wstatus[i]));
|
||||
|
||||
if (WIFSIGNALED(wstatus[i]) && WTERMSIG(wstatus[i]) == SIGUSR1)
|
||||
continue;
|
||||
|
||||
warnx("(pid=%d): Test failed", pid);
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
||||
warnx("(pid=%d): Test passed", pid);
|
||||
exit(EXIT_SUCCESS);
|
||||
}
|
Загрузка…
Ссылка в новой задаче