| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/fs/proc/base.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * |
| * proc base directory handling functions |
| * |
| * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. |
| * Instead of using magical inumbers to determine the kind of object |
| * we allocate and fill in-core inodes upon lookup. They don't even |
| * go into icache. We cache the reference to task_struct upon lookup too. |
| * Eventually it should become a filesystem in its own. We don't use the |
| * rest of procfs anymore. |
| * |
| * |
| * Changelog: |
| * 17-Jan-2005 |
| * Allan Bezerra |
| * Bruna Moreira <bruna.moreira@indt.org.br> |
| * Edjard Mota <edjard.mota@indt.org.br> |
| * Ilias Biris <ilias.biris@indt.org.br> |
| * Mauricio Lin <mauricio.lin@indt.org.br> |
| * |
| * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT |
| * |
| * A new process specific entry (smaps) included in /proc. It shows the |
| * size of rss for each memory area. The maps entry lacks information |
| * about physical memory size (rss) for each mapped file, i.e., |
| * rss information for executables and library files. |
| * This additional information is useful for any tools that need to know |
| * about physical memory consumption for a process specific library. |
| * |
| * Changelog: |
| * 21-Feb-2005 |
| * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT |
| * Pud inclusion in the page table walking. |
| * |
| * ChangeLog: |
| * 10-Mar-2005 |
| * 10LE Instituto Nokia de Tecnologia - INdT: |
| * A better way to walks through the page table as suggested by Hugh Dickins. |
| * |
| * Simo Piiroinen <simo.piiroinen@nokia.com>: |
| * Smaps information related to shared, private, clean and dirty pages. |
| * |
| * Paul Mundt <paul.mundt@nokia.com>: |
| * Overall revision about smaps. |
| */ |
| |
| #include <linux/uaccess.h> |
| |
| #include <linux/errno.h> |
| #include <linux/time.h> |
| #include <linux/proc_fs.h> |
| #include <linux/stat.h> |
| #include <linux/task_io_accounting_ops.h> |
| #include <linux/init.h> |
| #include <linux/capability.h> |
| #include <linux/file.h> |
| #include <linux/fdtable.h> |
| #include <linux/string.h> |
| #include <linux/seq_file.h> |
| #include <linux/namei.h> |
| #include <linux/mnt_namespace.h> |
| #include <linux/mm.h> |
| #include <linux/swap.h> |
| #include <linux/rcupdate.h> |
| #include <linux/kallsyms.h> |
| #include <linux/stacktrace.h> |
| #include <linux/resource.h> |
| #include <linux/module.h> |
| #include <linux/mount.h> |
| #include <linux/security.h> |
| #include <linux/ptrace.h> |
| #include <linux/tracehook.h> |
| #include <linux/printk.h> |
| #include <linux/cache.h> |
| #include <linux/cgroup.h> |
| #include <linux/cpuset.h> |
| #include <linux/audit.h> |
| #include <linux/poll.h> |
| #include <linux/nsproxy.h> |
| #include <linux/oom.h> |
| #include <linux/elf.h> |
| #include <linux/pid_namespace.h> |
| #include <linux/user_namespace.h> |
| #include <linux/fs_struct.h> |
| #include <linux/slab.h> |
| #include <linux/sched/autogroup.h> |
| #include <linux/sched/mm.h> |
| #include <linux/sched/coredump.h> |
| #include <linux/sched/debug.h> |
| #include <linux/sched/stat.h> |
| #include <linux/flex_array.h> |
| #include <linux/posix-timers.h> |
| #include <trace/events/oom.h> |
| #include "internal.h" |
| #include "fd.h" |
| |
| #include "../../lib/kstrtox.h" |
| |
| /* NOTE: |
| * Implementing inode permission operations in /proc is almost |
| * certainly an error. Permission checks need to happen during |
| * each system call not at open time. The reason is that most of |
| * what we wish to check for permissions in /proc varies at runtime. |
| * |
| * The classic example of a problem is opening file descriptors |
| * in /proc for a task before it execs a suid executable. |
| */ |
| |
| static u8 nlink_tid __ro_after_init; |
| static u8 nlink_tgid __ro_after_init; |
| |
| struct pid_entry { |
| const char *name; |
| unsigned int len; |
| umode_t mode; |
| const struct inode_operations *iop; |
| const struct file_operations *fop; |
| union proc_op op; |
| }; |
| |
| #define NOD(NAME, MODE, IOP, FOP, OP) { \ |
| .name = (NAME), \ |
| .len = sizeof(NAME) - 1, \ |
| .mode = MODE, \ |
| .iop = IOP, \ |
| .fop = FOP, \ |
| .op = OP, \ |
| } |
| |
| #define DIR(NAME, MODE, iops, fops) \ |
| NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) |
| #define LNK(NAME, get_link) \ |
| NOD(NAME, (S_IFLNK|S_IRWXUGO), \ |
| &proc_pid_link_inode_operations, NULL, \ |
| { .proc_get_link = get_link } ) |
| #define REG(NAME, MODE, fops) \ |
| NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) |
| #define ONE(NAME, MODE, show) \ |
| NOD(NAME, (S_IFREG|(MODE)), \ |
| NULL, &proc_single_file_operations, \ |
| { .proc_show = show } ) |
| |
| /* |
| * Count the number of hardlinks for the pid_entry table, excluding the . |
| * and .. links. |
| */ |
| static unsigned int __init pid_entry_nlink(const struct pid_entry *entries, |
| unsigned int n) |
| { |
| unsigned int i; |
| unsigned int count; |
| |
| count = 2; |
| for (i = 0; i < n; ++i) { |
| if (S_ISDIR(entries[i].mode)) |
| ++count; |
| } |
| |
| return count; |
| } |
| |
| static int get_task_root(struct task_struct *task, struct path *root) |
| { |
| int result = -ENOENT; |
| |
| task_lock(task); |
| if (task->fs) { |
| get_fs_root(task->fs, root); |
| result = 0; |
| } |
| task_unlock(task); |
| return result; |
| } |
| |
| static int proc_cwd_link(struct dentry *dentry, struct path *path) |
| { |
| struct task_struct *task = get_proc_task(d_inode(dentry)); |
| int result = -ENOENT; |
| |
| if (task) { |
| task_lock(task); |
| if (task->fs) { |
| get_fs_pwd(task->fs, path); |
| result = 0; |
| } |
| task_unlock(task); |
| put_task_struct(task); |
| } |
| return result; |
| } |
| |
| static int proc_root_link(struct dentry *dentry, struct path *path) |
| { |
| struct task_struct *task = get_proc_task(d_inode(dentry)); |
| int result = -ENOENT; |
| |
| if (task) { |
| result = get_task_root(task, path); |
| put_task_struct(task); |
| } |
| return result; |
| } |
| |
| static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| unsigned long arg_start, arg_end, env_start, env_end; |
| unsigned long pos, len; |
| char *page; |
| |
| /* Check if process spawned far enough to have cmdline. */ |
| if (!mm->env_end) |
| return 0; |
| |
| spin_lock(&mm->arg_lock); |
| arg_start = mm->arg_start; |
| arg_end = mm->arg_end; |
| env_start = mm->env_start; |
| env_end = mm->env_end; |
| spin_unlock(&mm->arg_lock); |
| |
| if (arg_start >= arg_end) |
| return 0; |
| |
| /* |
| * We have traditionally allowed the user to re-write |
| * the argument strings and overflow the end result |
| * into the environment section. But only do that if |
| * the environment area is contiguous to the arguments. |
| */ |
| if (env_start != arg_end || env_start >= env_end) |
| env_start = env_end = arg_end; |
| |
| /* .. and limit it to a maximum of one page of slop */ |
| if (env_end >= arg_end + PAGE_SIZE) |
| env_end = arg_end + PAGE_SIZE - 1; |
| |
| /* We're not going to care if "*ppos" has high bits set */ |
| pos = arg_start + *ppos; |
| |
| /* .. but we do check the result is in the proper range */ |
| if (pos < arg_start || pos >= env_end) |
| return 0; |
| |
| /* .. and we never go past env_end */ |
| if (env_end - pos < count) |
| count = env_end - pos; |
| |
| page = (char *)__get_free_page(GFP_KERNEL); |
| if (!page) |
| return -ENOMEM; |
| |
| len = 0; |
| while (count) { |
| int got; |
| size_t size = min_t(size_t, PAGE_SIZE, count); |
| long offset; |
| |
| /* |
| * Are we already starting past the official end? |
| * We always include the last byte that is *supposed* |
| * to be NUL |
| */ |
| offset = (pos >= arg_end) ? pos - arg_end + 1 : 0; |
| |
| got = access_remote_vm(mm, pos - offset, page, size + offset, FOLL_ANON); |
| if (got <= offset) |
| break; |
| got -= offset; |
| |
| /* Don't walk past a NUL character once you hit arg_end */ |
| if (pos + got >= arg_end) { |
| int n = 0; |
| |
| /* |
| * If we started before 'arg_end' but ended up |
| * at or after it, we start the NUL character |
| * check at arg_end-1 (where we expect the normal |
| * EOF to be). |
| * |
| * NOTE! This is smaller than 'got', because |
| * pos + got >= arg_end |
| */ |
| if (pos < arg_end) |
| n = arg_end - pos - 1; |
| |
| /* Cut off at first NUL after 'n' */ |
| got = n + strnlen(page+n, offset+got-n); |
| if (got < offset) |
| break; |
| got -= offset; |
| |
| /* Include the NUL if it existed */ |
| if (got < size) |
| got++; |
| } |
| |
| got -= copy_to_user(buf, page+offset, got); |
| if (unlikely(!got)) { |
| if (!len) |
| len = -EFAULT; |
| break; |
| } |
| pos += got; |
| buf += got; |
| len += got; |
| count -= got; |
| } |
| |
| free_page((unsigned long)page); |
| return len; |
| } |
| |
| static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf, |
| size_t count, loff_t *pos) |
| { |
| struct mm_struct *mm; |
| ssize_t ret; |
| |
| mm = get_task_mm(tsk); |
| if (!mm) |
| return 0; |
| |
| ret = get_mm_cmdline(mm, buf, count, pos); |
| mmput(mm); |
| return ret; |
| } |
| |
| static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, |
| size_t count, loff_t *pos) |
| { |
| struct task_struct *tsk; |
| ssize_t ret; |
| |
| BUG_ON(*pos < 0); |
| |
| tsk = get_proc_task(file_inode(file)); |
| if (!tsk) |
| return -ESRCH; |
| ret = get_task_cmdline(tsk, buf, count, pos); |
| put_task_struct(tsk); |
| if (ret > 0) |
| *pos += ret; |
| return ret; |
| } |
| |
| static const struct file_operations proc_pid_cmdline_ops = { |
| .read = proc_pid_cmdline_read, |
| .llseek = generic_file_llseek, |
| }; |
| |
| #ifdef CONFIG_KALLSYMS |
| /* |
| * Provides a wchan file via kallsyms in a proper one-value-per-file format. |
| * Returns the resolved symbol. If that fails, simply return the address. |
| */ |
| static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| unsigned long wchan; |
| char symname[KSYM_NAME_LEN]; |
| |
| if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) |
| goto print0; |
| |
| wchan = get_wchan(task); |
| if (wchan && !lookup_symbol_name(wchan, symname)) { |
| seq_puts(m, symname); |
| return 0; |
| } |
| |
| print0: |
| seq_putc(m, '0'); |
| return 0; |
| } |
| #endif /* CONFIG_KALLSYMS */ |
| |
| static int lock_trace(struct task_struct *task) |
| { |
| int err = mutex_lock_killable(&task->signal->cred_guard_mutex); |
| if (err) |
| return err; |
| if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { |
| mutex_unlock(&task->signal->cred_guard_mutex); |
| return -EPERM; |
| } |
| return 0; |
| } |
| |
| static void unlock_trace(struct task_struct *task) |
| { |
| mutex_unlock(&task->signal->cred_guard_mutex); |
| } |
| |
| #ifdef CONFIG_STACKTRACE |
| |
| #define MAX_STACK_TRACE_DEPTH 64 |
| |
| static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| struct stack_trace trace; |
| unsigned long *entries; |
| int err; |
| |
| /* |
| * The ability to racily run the kernel stack unwinder on a running task |
| * and then observe the unwinder output is scary; while it is useful for |
| * debugging kernel issues, it can also allow an attacker to leak kernel |
| * stack contents. |
| * Doing this in a manner that is at least safe from races would require |
| * some work to ensure that the remote task can not be scheduled; and |
| * even then, this would still expose the unwinder as local attack |
| * surface. |
| * Therefore, this interface is restricted to root. |
| */ |
| if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) |
| return -EACCES; |
| |
| entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries), |
| GFP_KERNEL); |
| if (!entries) |
| return -ENOMEM; |
| |
| trace.nr_entries = 0; |
| trace.max_entries = MAX_STACK_TRACE_DEPTH; |
| trace.entries = entries; |
| trace.skip = 0; |
| |
| err = lock_trace(task); |
| if (!err) { |
| unsigned int i; |
| |
| save_stack_trace_tsk(task, &trace); |
| |
| for (i = 0; i < trace.nr_entries; i++) { |
| seq_printf(m, "[<0>] %pB\n", (void *)entries[i]); |
| } |
| unlock_trace(task); |
| } |
| kfree(entries); |
| |
| return err; |
| } |
| #endif |
| |
| #ifdef CONFIG_SCHED_INFO |
| /* |
| * Provides /proc/PID/schedstat |
| */ |
| static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| if (unlikely(!sched_info_on())) |
| seq_printf(m, "0 0 0\n"); |
| else |
| seq_printf(m, "%llu %llu %lu\n", |
| (unsigned long long)task->se.sum_exec_runtime, |
| (unsigned long long)task->sched_info.run_delay, |
| task->sched_info.pcount); |
| |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_LATENCYTOP |
| static int lstats_show_proc(struct seq_file *m, void *v) |
| { |
| int i; |
| struct inode *inode = m->private; |
| struct task_struct *task = get_proc_task(inode); |
| |
| if (!task) |
| return -ESRCH; |
| seq_puts(m, "Latency Top version : v0.1\n"); |
| for (i = 0; i < LT_SAVECOUNT; i++) { |
| struct latency_record *lr = &task->latency_record[i]; |
| if (lr->backtrace[0]) { |
| int q; |
| seq_printf(m, "%i %li %li", |
| lr->count, lr->time, lr->max); |
| for (q = 0; q < LT_BACKTRACEDEPTH; q++) { |
| unsigned long bt = lr->backtrace[q]; |
| if (!bt) |
| break; |
| if (bt == ULONG_MAX) |
| break; |
| seq_printf(m, " %ps", (void *)bt); |
| } |
| seq_putc(m, '\n'); |
| } |
| |
| } |
| put_task_struct(task); |
| return 0; |
| } |
| |
| static int lstats_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, lstats_show_proc, inode); |
| } |
| |
| static ssize_t lstats_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *offs) |
| { |
| struct task_struct *task = get_proc_task(file_inode(file)); |
| |
| if (!task) |
| return -ESRCH; |
| clear_all_latency_tracing(task); |
| put_task_struct(task); |
| |
| return count; |
| } |
| |
| static const struct file_operations proc_lstats_operations = { |
| .open = lstats_open, |
| .read = seq_read, |
| .write = lstats_write, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| #endif |
| |
| static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| unsigned long totalpages = totalram_pages + total_swap_pages; |
| unsigned long points = 0; |
| |
| points = oom_badness(task, NULL, NULL, totalpages) * |
| 1000 / totalpages; |
| seq_printf(m, "%lu\n", points); |
| |
| return 0; |
| } |
| |
| struct limit_names { |
| const char *name; |
| const char *unit; |
| }; |
| |
| static const struct limit_names lnames[RLIM_NLIMITS] = { |
| [RLIMIT_CPU] = {"Max cpu time", "seconds"}, |
| [RLIMIT_FSIZE] = {"Max file size", "bytes"}, |
| [RLIMIT_DATA] = {"Max data size", "bytes"}, |
| [RLIMIT_STACK] = {"Max stack size", "bytes"}, |
| [RLIMIT_CORE] = {"Max core file size", "bytes"}, |
| [RLIMIT_RSS] = {"Max resident set", "bytes"}, |
| [RLIMIT_NPROC] = {"Max processes", "processes"}, |
| [RLIMIT_NOFILE] = {"Max open files", "files"}, |
| [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, |
| [RLIMIT_AS] = {"Max address space", "bytes"}, |
| [RLIMIT_LOCKS] = {"Max file locks", "locks"}, |
| [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, |
| [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, |
| [RLIMIT_NICE] = {"Max nice priority", NULL}, |
| [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, |
| [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, |
| }; |
| |
| /* Display limits for a process */ |
| static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| unsigned int i; |
| unsigned long flags; |
| |
| struct rlimit rlim[RLIM_NLIMITS]; |
| |
| if (!lock_task_sighand(task, &flags)) |
| return 0; |
| memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); |
| unlock_task_sighand(task, &flags); |
| |
| /* |
| * print the file header |
| */ |
| seq_printf(m, "%-25s %-20s %-20s %-10s\n", |
| "Limit", "Soft Limit", "Hard Limit", "Units"); |
| |
| for (i = 0; i < RLIM_NLIMITS; i++) { |
| if (rlim[i].rlim_cur == RLIM_INFINITY) |
| seq_printf(m, "%-25s %-20s ", |
| lnames[i].name, "unlimited"); |
| else |
| seq_printf(m, "%-25s %-20lu ", |
| lnames[i].name, rlim[i].rlim_cur); |
| |
| if (rlim[i].rlim_max == RLIM_INFINITY) |
| seq_printf(m, "%-20s ", "unlimited"); |
| else |
| seq_printf(m, "%-20lu ", rlim[i].rlim_max); |
| |
| if (lnames[i].unit) |
| seq_printf(m, "%-10s\n", lnames[i].unit); |
| else |
| seq_putc(m, '\n'); |
| } |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
| static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| long nr; |
| unsigned long args[6], sp, pc; |
| int res; |
| |
| res = lock_trace(task); |
| if (res) |
| return res; |
| |
| if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) |
| seq_puts(m, "running\n"); |
| else if (nr < 0) |
| seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); |
| else |
| seq_printf(m, |
| "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", |
| nr, |
| args[0], args[1], args[2], args[3], args[4], args[5], |
| sp, pc); |
| unlock_trace(task); |
| |
| return 0; |
| } |
| #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ |
| |
| /************************************************************************/ |
| /* Here the fs part begins */ |
| /************************************************************************/ |
| |
| /* permission checks */ |
| static int proc_fd_access_allowed(struct inode *inode) |
| { |
| struct task_struct *task; |
| int allowed = 0; |
| /* Allow access to a task's file descriptors if it is us or we |
| * may use ptrace attach to the process and find out that |
| * information. |
| */ |
| task = get_proc_task(inode); |
| if (task) { |
| allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); |
| put_task_struct(task); |
| } |
| return allowed; |
| } |
| |
| int proc_setattr(struct dentry *dentry, struct iattr *attr) |
| { |
| int error; |
| struct inode *inode = d_inode(dentry); |
| |
| if (attr->ia_valid & ATTR_MODE) |
| return -EPERM; |
| |
| error = setattr_prepare(dentry, attr); |
| if (error) |
| return error; |
| |
| setattr_copy(inode, attr); |
| mark_inode_dirty(inode); |
| return 0; |
| } |
| |
| /* |
| * May current process learn task's sched/cmdline info (for hide_pid_min=1) |
| * or euid/egid (for hide_pid_min=2)? |
| */ |
| static bool has_pid_permissions(struct pid_namespace *pid, |
| struct task_struct *task, |
| int hide_pid_min) |
| { |
| if (pid->hide_pid < hide_pid_min) |
| return true; |
| if (in_group_p(pid->pid_gid)) |
| return true; |
| return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); |
| } |
| |
| |
| static int proc_pid_permission(struct inode *inode, int mask) |
| { |
| struct pid_namespace *pid = proc_pid_ns(inode); |
| struct task_struct *task; |
| bool has_perms; |
| |
| task = get_proc_task(inode); |
| if (!task) |
| return -ESRCH; |
| has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS); |
| put_task_struct(task); |
| |
| if (!has_perms) { |
| if (pid->hide_pid == HIDEPID_INVISIBLE) { |
| /* |
| * Let's make getdents(), stat(), and open() |
| * consistent with each other. If a process |
| * may not stat() a file, it shouldn't be seen |
| * in procfs at all. |
| */ |
| return -ENOENT; |
| } |
| |
| return -EPERM; |
| } |
| return generic_permission(inode, mask); |
| } |
| |
| |
| |
| static const struct inode_operations proc_def_inode_operations = { |
| .setattr = proc_setattr, |
| }; |
| |
| static int proc_single_show(struct seq_file *m, void *v) |
| { |
| struct inode *inode = m->private; |
| struct pid_namespace *ns = proc_pid_ns(inode); |
| struct pid *pid = proc_pid(inode); |
| struct task_struct *task; |
| int ret; |
| |
| task = get_pid_task(pid, PIDTYPE_PID); |
| if (!task) |
| return -ESRCH; |
| |
| ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); |
| |
| put_task_struct(task); |
| return ret; |
| } |
| |
| static int proc_single_open(struct inode *inode, struct file *filp) |
| { |
| return single_open(filp, proc_single_show, inode); |
| } |
| |
| static const struct file_operations proc_single_file_operations = { |
| .open = proc_single_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| |
| struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) |
| { |
| struct task_struct *task = get_proc_task(inode); |
| struct mm_struct *mm = ERR_PTR(-ESRCH); |
| |
| if (task) { |
| mm = mm_access(task, mode | PTRACE_MODE_FSCREDS); |
| put_task_struct(task); |
| |
| if (!IS_ERR_OR_NULL(mm)) { |
| /* ensure this mm_struct can't be freed */ |
| mmgrab(mm); |
| /* but do not pin its memory */ |
| mmput(mm); |
| } |
| } |
| |
| return mm; |
| } |
| |
| static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) |
| { |
| struct mm_struct *mm = proc_mem_open(inode, mode); |
| |
| if (IS_ERR(mm)) |
| return PTR_ERR(mm); |
| |
| file->private_data = mm; |
| return 0; |
| } |
| |
| static int mem_open(struct inode *inode, struct file *file) |
| { |
| int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); |
| |
| /* OK to pass negative loff_t, we can catch out-of-range */ |
| file->f_mode |= FMODE_UNSIGNED_OFFSET; |
| |
| return ret; |
| } |
| |
| static ssize_t mem_rw(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos, int write) |
| { |
| struct mm_struct *mm = file->private_data; |
| unsigned long addr = *ppos; |
| ssize_t copied; |
| char *page; |
| unsigned int flags; |
| |
| if (!mm) |
| return 0; |
| |
| page = (char *)__get_free_page(GFP_KERNEL); |
| if (!page) |
| return -ENOMEM; |
| |
| copied = 0; |
| if (!mmget_not_zero(mm)) |
| goto free; |
| |
| flags = FOLL_FORCE | (write ? FOLL_WRITE : 0); |
| |
| while (count > 0) { |
| int this_len = min_t(int, count, PAGE_SIZE); |
| |
| if (write && copy_from_user(page, buf, this_len)) { |
| copied = -EFAULT; |
| break; |
| } |
| |
| this_len = access_remote_vm(mm, addr, page, this_len, flags); |
| if (!this_len) { |
| if (!copied) |
| copied = -EIO; |
| break; |
| } |
| |
| if (!write && copy_to_user(buf, page, this_len)) { |
| copied = -EFAULT; |
| break; |
| } |
| |
| buf += this_len; |
| addr += this_len; |
| copied += this_len; |
| count -= this_len; |
| } |
| *ppos = addr; |
| |
| mmput(mm); |
| free: |
| free_page((unsigned long) page); |
| return copied; |
| } |
| |
| static ssize_t mem_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| return mem_rw(file, buf, count, ppos, 0); |
| } |
| |
| static ssize_t mem_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| return mem_rw(file, (char __user*)buf, count, ppos, 1); |
| } |
| |
| loff_t mem_lseek(struct file *file, loff_t offset, int orig) |
| { |
| switch (orig) { |
| case 0: |
| file->f_pos = offset; |
| break; |
| case 1: |
| file->f_pos += offset; |
| break; |
| default: |
| return -EINVAL; |
| } |
| force_successful_syscall_return(); |
| return file->f_pos; |
| } |
| |
| static int mem_release(struct inode *inode, struct file *file) |
| { |
| struct mm_struct *mm = file->private_data; |
| if (mm) |
| mmdrop(mm); |
| return 0; |
| } |
| |
| static const struct file_operations proc_mem_operations = { |
| .llseek = mem_lseek, |
| .read = mem_read, |
| .write = mem_write, |
| .open = mem_open, |
| .release = mem_release, |
| }; |
| |
| static int environ_open(struct inode *inode, struct file *file) |
| { |
| return __mem_open(inode, file, PTRACE_MODE_READ); |
| } |
| |
| static ssize_t environ_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| char *page; |
| unsigned long src = *ppos; |
| int ret = 0; |
| struct mm_struct *mm = file->private_data; |
| unsigned long env_start, env_end; |
| |
| /* Ensure the process spawned far enough to have an environment. */ |
| if (!mm || !mm->env_end) |
| return 0; |
| |
| page = (char *)__get_free_page(GFP_KERNEL); |
| if (!page) |
| return -ENOMEM; |
| |
| ret = 0; |
| if (!mmget_not_zero(mm)) |
| goto free; |
| |
| spin_lock(&mm->arg_lock); |
| env_start = mm->env_start; |
| env_end = mm->env_end; |
| spin_unlock(&mm->arg_lock); |
| |
| while (count > 0) { |
| size_t this_len, max_len; |
| int retval; |
| |
| if (src >= (env_end - env_start)) |
| break; |
| |
| this_len = env_end - (env_start + src); |
| |
| max_len = min_t(size_t, PAGE_SIZE, count); |
| this_len = min(max_len, this_len); |
| |
| retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON); |
| |
| if (retval <= 0) { |
| ret = retval; |
| break; |
| } |
| |
| if (copy_to_user(buf, page, retval)) { |
| ret = -EFAULT; |
| break; |
| } |
| |
| ret += retval; |
| src += retval; |
| buf += retval; |
| count -= retval; |
| } |
| *ppos = src; |
| mmput(mm); |
| |
| free: |
| free_page((unsigned long) page); |
| return ret; |
| } |
| |
| static const struct file_operations proc_environ_operations = { |
| .open = environ_open, |
| .read = environ_read, |
| .llseek = generic_file_llseek, |
| .release = mem_release, |
| }; |
| |
| static int auxv_open(struct inode *inode, struct file *file) |
| { |
| return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); |
| } |
| |
| static ssize_t auxv_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct mm_struct *mm = file->private_data; |
| unsigned int nwords = 0; |
| |
| if (!mm) |
| return 0; |
| do { |
| nwords += 2; |
| } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ |
| return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv, |
| nwords * sizeof(mm->saved_auxv[0])); |
| } |
| |
| static const struct file_operations proc_auxv_operations = { |
| .open = auxv_open, |
| .read = auxv_read, |
| .llseek = generic_file_llseek, |
| .release = mem_release, |
| }; |
| |
| static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, |
| loff_t *ppos) |
| { |
| struct task_struct *task = get_proc_task(file_inode(file)); |
| char buffer[PROC_NUMBUF]; |
| int oom_adj = OOM_ADJUST_MIN; |
| size_t len; |
| |
| if (!task) |
| return -ESRCH; |
| if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) |
| oom_adj = OOM_ADJUST_MAX; |
| else |
| oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / |
| OOM_SCORE_ADJ_MAX; |
| put_task_struct(task); |
| len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); |
| return simple_read_from_buffer(buf, count, ppos, buffer, len); |
| } |
| |
| static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) |
| { |
| static DEFINE_MUTEX(oom_adj_mutex); |
| struct mm_struct *mm = NULL; |
| struct task_struct *task; |
| int err = 0; |
| |
| task = get_proc_task(file_inode(file)); |
| if (!task) |
| return -ESRCH; |
| |
| mutex_lock(&oom_adj_mutex); |
| if (legacy) { |
| if (oom_adj < task->signal->oom_score_adj && |
| !capable(CAP_SYS_RESOURCE)) { |
| err = -EACCES; |
| goto err_unlock; |
| } |
| /* |
| * /proc/pid/oom_adj is provided for legacy purposes, ask users to use |
| * /proc/pid/oom_score_adj instead. |
| */ |
| pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", |
| current->comm, task_pid_nr(current), task_pid_nr(task), |
| task_pid_nr(task)); |
| } else { |
| if ((short)oom_adj < task->signal->oom_score_adj_min && |
| !capable(CAP_SYS_RESOURCE)) { |
| err = -EACCES; |
| goto err_unlock; |
| } |
| } |
| |
| /* |
| * Make sure we will check other processes sharing the mm if this is |
| * not vfrok which wants its own oom_score_adj. |
| * pin the mm so it doesn't go away and get reused after task_unlock |
| */ |
| if (!task->vfork_done) { |
| struct task_struct *p = find_lock_task_mm(task); |
| |
| if (p) { |
| if (atomic_read(&p->mm->mm_users) > 1) { |
| mm = p->mm; |
| mmgrab(mm); |
| } |
| task_unlock(p); |
| } |
| } |
| |
| task->signal->oom_score_adj = oom_adj; |
| if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) |
| task->signal->oom_score_adj_min = (short)oom_adj; |
| trace_oom_score_adj_update(task); |
| |
| if (mm) { |
| struct task_struct *p; |
| |
| rcu_read_lock(); |
| for_each_process(p) { |
| if (same_thread_group(task, p)) |
| continue; |
| |
| /* do not touch kernel threads or the global init */ |
| if (p->flags & PF_KTHREAD || is_global_init(p)) |
| continue; |
| |
| task_lock(p); |
| if (!p->vfork_done && process_shares_mm(p, mm)) { |
| pr_info("updating oom_score_adj for %d (%s) from %d to %d because it shares mm with %d (%s). Report if this is unexpected.\n", |
| task_pid_nr(p), p->comm, |
| p->signal->oom_score_adj, oom_adj, |
| task_pid_nr(task), task->comm); |
| p->signal->oom_score_adj = oom_adj; |
| if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) |
| p->signal->oom_score_adj_min = (short)oom_adj; |
| } |
| task_unlock(p); |
| } |
| rcu_read_unlock(); |
| mmdrop(mm); |
| } |
| err_unlock: |
| mutex_unlock(&oom_adj_mutex); |
| put_task_struct(task); |
| return err; |
| } |
| |
| /* |
| * /proc/pid/oom_adj exists solely for backwards compatibility with previous |
| * kernels. The effective policy is defined by oom_score_adj, which has a |
| * different scale: oom_adj grew exponentially and oom_score_adj grows linearly. |
| * Values written to oom_adj are simply mapped linearly to oom_score_adj. |
| * Processes that become oom disabled via oom_adj will still be oom disabled |
| * with this implementation. |
| * |
| * oom_adj cannot be removed since existing userspace binaries use it. |
| */ |
| static ssize_t oom_adj_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| char buffer[PROC_NUMBUF]; |
| int oom_adj; |
| int err; |
| |
| memset(buffer, 0, sizeof(buffer)); |
| if (count > sizeof(buffer) - 1) |
| count = sizeof(buffer) - 1; |
| if (copy_from_user(buffer, buf, count)) { |
| err = -EFAULT; |
| goto out; |
| } |
| |
| err = kstrtoint(strstrip(buffer), 0, &oom_adj); |
| if (err) |
| goto out; |
| if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && |
| oom_adj != OOM_DISABLE) { |
| err = -EINVAL; |
| goto out; |
| } |
| |
| /* |
| * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum |
| * value is always attainable. |
| */ |
| if (oom_adj == OOM_ADJUST_MAX) |
| oom_adj = OOM_SCORE_ADJ_MAX; |
| else |
| oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; |
| |
| err = __set_oom_adj(file, oom_adj, true); |
| out: |
| return err < 0 ? err : count; |
| } |
| |
| static const struct file_operations proc_oom_adj_operations = { |
| .read = oom_adj_read, |
| .write = oom_adj_write, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static ssize_t oom_score_adj_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct task_struct *task = get_proc_task(file_inode(file)); |
| char buffer[PROC_NUMBUF]; |
| short oom_score_adj = OOM_SCORE_ADJ_MIN; |
| size_t len; |
| |
| if (!task) |
| return -ESRCH; |
| oom_score_adj = task->signal->oom_score_adj; |
| put_task_struct(task); |
| len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); |
| return simple_read_from_buffer(buf, count, ppos, buffer, len); |
| } |
| |
| static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| char buffer[PROC_NUMBUF]; |
| int oom_score_adj; |
| int err; |
| |
| memset(buffer, 0, sizeof(buffer)); |
| if (count > sizeof(buffer) - 1) |
| count = sizeof(buffer) - 1; |
| if (copy_from_user(buffer, buf, count)) { |
| err = -EFAULT; |
| goto out; |
| } |
| |
| err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); |
| if (err) |
| goto out; |
| if (oom_score_adj < OOM_SCORE_ADJ_MIN || |
| oom_score_adj > OOM_SCORE_ADJ_MAX) { |
| err = -EINVAL; |
| goto out; |
| } |
| |
| err = __set_oom_adj(file, oom_score_adj, false); |
| out: |
| return err < 0 ? err : count; |
| } |
| |
| static const struct file_operations proc_oom_score_adj_operations = { |
| .read = oom_score_adj_read, |
| .write = oom_score_adj_write, |
| .llseek = default_llseek, |
| }; |
| |
| #ifdef CONFIG_AUDITSYSCALL |
| #define TMPBUFLEN 11 |
| static ssize_t proc_loginuid_read(struct file * file, char __user * buf, |
| size_t count, loff_t *ppos) |
| { |
| struct inode * inode = file_inode(file); |
| struct task_struct *task = get_proc_task(inode); |
| ssize_t length; |
| char tmpbuf[TMPBUFLEN]; |
| |
| if (!task) |
| return -ESRCH; |
| length = scnprintf(tmpbuf, TMPBUFLEN, "%u", |
| from_kuid(file->f_cred->user_ns, |
| audit_get_loginuid(task))); |
| put_task_struct(task); |
| return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); |
| } |
| |
| static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, |
| size_t count, loff_t *ppos) |
| { |
| struct inode * inode = file_inode(file); |
| uid_t loginuid; |
| kuid_t kloginuid; |
| int rv; |
| |
| rcu_read_lock(); |
| if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { |
| rcu_read_unlock(); |
| return -EPERM; |
| } |
| rcu_read_unlock(); |
| |
| if (*ppos != 0) { |
| /* No partial writes. */ |
| return -EINVAL; |
| } |
| |
| rv = kstrtou32_from_user(buf, count, 10, &loginuid); |
| if (rv < 0) |
| return rv; |
| |
| /* is userspace tring to explicitly UNSET the loginuid? */ |
| if (loginuid == AUDIT_UID_UNSET) { |
| kloginuid = INVALID_UID; |
| } else { |
| kloginuid = make_kuid(file->f_cred->user_ns, loginuid); |
| if (!uid_valid(kloginuid)) |
| return -EINVAL; |
| } |
| |
| rv = audit_set_loginuid(kloginuid); |
| if (rv < 0) |
| return rv; |
| return count; |
| } |
| |
| static const struct file_operations proc_loginuid_operations = { |
| .read = proc_loginuid_read, |
| .write = proc_loginuid_write, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static ssize_t proc_sessionid_read(struct file * file, char __user * buf, |
| size_t count, loff_t *ppos) |
| { |
| struct inode * inode = file_inode(file); |
| struct task_struct *task = get_proc_task(inode); |
| ssize_t length; |
| char tmpbuf[TMPBUFLEN]; |
| |
| if (!task) |
| return -ESRCH; |
| length = scnprintf(tmpbuf, TMPBUFLEN, "%u", |
| audit_get_sessionid(task)); |
| put_task_struct(task); |
| return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); |
| } |
| |
| static const struct file_operations proc_sessionid_operations = { |
| .read = proc_sessionid_read, |
| .llseek = generic_file_llseek, |
| }; |
| #endif |
| |
| #ifdef CONFIG_FAULT_INJECTION |
| static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, |
| size_t count, loff_t *ppos) |
| { |
| struct task_struct *task = get_proc_task(file_inode(file)); |
| char buffer[PROC_NUMBUF]; |
| size_t len; |
| int make_it_fail; |
| |
| if (!task) |
| return -ESRCH; |
| make_it_fail = task->make_it_fail; |
| put_task_struct(task); |
| |
| len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); |
| |
| return simple_read_from_buffer(buf, count, ppos, buffer, len); |
| } |
| |
| static ssize_t proc_fault_inject_write(struct file * file, |
| const char __user * buf, size_t count, loff_t *ppos) |
| { |
| struct task_struct *task; |
| char buffer[PROC_NUMBUF]; |
| int make_it_fail; |
| int rv; |
| |
| if (!capable(CAP_SYS_RESOURCE)) |
| return -EPERM; |
| memset(buffer, 0, sizeof(buffer)); |
| if (count > sizeof(buffer) - 1) |
| count = sizeof(buffer) - 1; |
| if (copy_from_user(buffer, buf, count)) |
| return -EFAULT; |
| rv = kstrtoint(strstrip(buffer), 0, &make_it_fail); |
| if (rv < 0) |
| return rv; |
| if (make_it_fail < 0 || make_it_fail > 1) |
| return -EINVAL; |
| |
| task = get_proc_task(file_inode(file)); |
| if (!task) |
| return -ESRCH; |
| task->make_it_fail = make_it_fail; |
| put_task_struct(task); |
| |
| return count; |
| } |
| |
| static const struct file_operations proc_fault_inject_operations = { |
| .read = proc_fault_inject_read, |
| .write = proc_fault_inject_write, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct task_struct *task; |
| int err; |
| unsigned int n; |
| |
| err = kstrtouint_from_user(buf, count, 0, &n); |
| if (err) |
| return err; |
| |
| task = get_proc_task(file_inode(file)); |
| if (!task) |
| return -ESRCH; |
| task->fail_nth = n; |
| put_task_struct(task); |
| |
| return count; |
| } |
| |
| static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct task_struct *task; |
| char numbuf[PROC_NUMBUF]; |
| ssize_t len; |
| |
| task = get_proc_task(file_inode(file)); |
| if (!task) |
| return -ESRCH; |
| len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth); |
| put_task_struct(task); |
| return simple_read_from_buffer(buf, count, ppos, numbuf, len); |
| } |
| |
| static const struct file_operations proc_fail_nth_operations = { |
| .read = proc_fail_nth_read, |
| .write = proc_fail_nth_write, |
| }; |
| #endif |
| |
| |
| #ifdef CONFIG_SCHED_DEBUG |
| /* |
| * Print out various scheduling related per-task fields: |
| */ |
| static int sched_show(struct seq_file *m, void *v) |
| { |
| struct inode *inode = m->private; |
| struct pid_namespace *ns = proc_pid_ns(inode); |
| struct task_struct *p; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| proc_sched_show_task(p, ns, m); |
| |
| put_task_struct(p); |
| |
| return 0; |
| } |
| |
| static ssize_t |
| sched_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *offset) |
| { |
| struct inode *inode = file_inode(file); |
| struct task_struct *p; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| proc_sched_set_task(p); |
| |
| put_task_struct(p); |
| |
| return count; |
| } |
| |
| static int sched_open(struct inode *inode, struct file *filp) |
| { |
| return single_open(filp, sched_show, inode); |
| } |
| |
| static const struct file_operations proc_pid_sched_operations = { |
| .open = sched_open, |
| .read = seq_read, |
| .write = sched_write, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| #endif |
| |
| #ifdef CONFIG_SCHED_AUTOGROUP |
| /* |
| * Print out autogroup related information: |
| */ |
| static int sched_autogroup_show(struct seq_file *m, void *v) |
| { |
| struct inode *inode = m->private; |
| struct task_struct *p; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| proc_sched_autogroup_show_task(p, m); |
| |
| put_task_struct(p); |
| |
| return 0; |
| } |
| |
| static ssize_t |
| sched_autogroup_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *offset) |
| { |
| struct inode *inode = file_inode(file); |
| struct task_struct *p; |
| char buffer[PROC_NUMBUF]; |
| int nice; |
| int err; |
| |
| memset(buffer, 0, sizeof(buffer)); |
| if (count > sizeof(buffer) - 1) |
| count = sizeof(buffer) - 1; |
| if (copy_from_user(buffer, buf, count)) |
| return -EFAULT; |
| |
| err = kstrtoint(strstrip(buffer), 0, &nice); |
| if (err < 0) |
| return err; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| |
| err = proc_sched_autogroup_set_nice(p, nice); |
| if (err) |
| count = err; |
| |
| put_task_struct(p); |
| |
| return count; |
| } |
| |
| static int sched_autogroup_open(struct inode *inode, struct file *filp) |
| { |
| int ret; |
| |
| ret = single_open(filp, sched_autogroup_show, NULL); |
| if (!ret) { |
| struct seq_file *m = filp->private_data; |
| |
| m->private = inode; |
| } |
| return ret; |
| } |
| |
| static const struct file_operations proc_pid_sched_autogroup_operations = { |
| .open = sched_autogroup_open, |
| .read = seq_read, |
| .write = sched_autogroup_write, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| #endif /* CONFIG_SCHED_AUTOGROUP */ |
| |
| static ssize_t comm_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *offset) |
| { |
| struct inode *inode = file_inode(file); |
| struct task_struct *p; |
| char buffer[TASK_COMM_LEN]; |
| const size_t maxlen = sizeof(buffer) - 1; |
| |
| memset(buffer, 0, sizeof(buffer)); |
| if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) |
| return -EFAULT; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| |
| if (same_thread_group(current, p)) |
| set_task_comm(p, buffer); |
| else |
| count = -EINVAL; |
| |
| put_task_struct(p); |
| |
| return count; |
| } |
| |
| static int comm_show(struct seq_file *m, void *v) |
| { |
| struct inode *inode = m->private; |
| struct task_struct *p; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| |
| proc_task_name(m, p, false); |
| seq_putc(m, '\n'); |
| |
| put_task_struct(p); |
| |
| return 0; |
| } |
| |
| static int comm_open(struct inode *inode, struct file *filp) |
| { |
| return single_open(filp, comm_show, inode); |
| } |
| |
| static const struct file_operations proc_pid_set_comm_operations = { |
| .open = comm_open, |
| .read = seq_read, |
| .write = comm_write, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static int proc_exe_link(struct dentry *dentry, struct path *exe_path) |
| { |
| struct task_struct *task; |
| struct file *exe_file; |
| |
| task = get_proc_task(d_inode(dentry)); |
| if (!task) |
| return -ENOENT; |
| exe_file = get_task_exe_file(task); |
| put_task_struct(task); |
| if (exe_file) { |
| *exe_path = exe_file->f_path; |
| path_get(&exe_file->f_path); |
| fput(exe_file); |
| return 0; |
| } else |
| return -ENOENT; |
| } |
| |
| static const char *proc_pid_get_link(struct dentry *dentry, |
| struct inode *inode, |
| struct delayed_call *done) |
| { |
| struct path path; |
| int error = -EACCES; |
| |
| if (!dentry) |
| return ERR_PTR(-ECHILD); |
| |
| /* Are we allowed to snoop on the tasks file descriptors? */ |
| if (!proc_fd_access_allowed(inode)) |
| goto out; |
| |
| error = PROC_I(inode)->op.proc_get_link(dentry, &path); |
| if (error) |
| goto out; |
| |
| nd_jump_link(&path); |
| return NULL; |
| out: |
| return ERR_PTR(error); |
| } |
| |
| static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) |
| { |
| char *tmp = (char *)__get_free_page(GFP_KERNEL); |
| char *pathname; |
| int len; |
| |
| if (!tmp) |
| return -ENOMEM; |
| |
| pathname = d_path(path, tmp, PAGE_SIZE); |
| len = PTR_ERR(pathname); |
| if (IS_ERR(pathname)) |
| goto out; |
| len = tmp + PAGE_SIZE - 1 - pathname; |
| |
| if (len > buflen) |
| len = buflen; |
| if (copy_to_user(buffer, pathname, len)) |
| len = -EFAULT; |
| out: |
| free_page((unsigned long)tmp); |
| return len; |
| } |
| |
| static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) |
| { |
| int error = -EACCES; |
| struct inode *inode = d_inode(dentry); |
| struct path path; |
| |
| /* Are we allowed to snoop on the tasks file descriptors? */ |
| if (!proc_fd_access_allowed(inode)) |
| goto out; |
| |
| error = PROC_I(inode)->op.proc_get_link(dentry, &path); |
| if (error) |
| goto out; |
| |
| error = do_proc_readlink(&path, buffer, buflen); |
| path_put(&path); |
| out: |
| return error; |
| } |
| |
| const struct inode_operations proc_pid_link_inode_operations = { |
| .readlink = proc_pid_readlink, |
| .get_link = proc_pid_get_link, |
| .setattr = proc_setattr, |
| }; |
| |
| |
| /* building an inode */ |
| |
| void task_dump_owner(struct task_struct *task, umode_t mode, |
| kuid_t *ruid, kgid_t *rgid) |
| { |
| /* Depending on the state of dumpable compute who should own a |
| * proc file for a task. |
| */ |
| const struct cred *cred; |
| kuid_t uid; |
| kgid_t gid; |
| |
| if (unlikely(task->flags & PF_KTHREAD)) { |
| *ruid = GLOBAL_ROOT_UID; |
| *rgid = GLOBAL_ROOT_GID; |
| return; |
| } |
| |
| /* Default to the tasks effective ownership */ |
| rcu_read_lock(); |
| cred = __task_cred(task); |
| uid = cred->euid; |
| gid = cred->egid; |
| rcu_read_unlock(); |
| |
| /* |
| * Before the /proc/pid/status file was created the only way to read |
| * the effective uid of a /process was to stat /proc/pid. Reading |
| * /proc/pid/status is slow enough that procps and other packages |
| * kept stating /proc/pid. To keep the rules in /proc simple I have |
| * made this apply to all per process world readable and executable |
| * directories. |
| */ |
| if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { |
| struct mm_struct *mm; |
| task_lock(task); |
| mm = task->mm; |
| /* Make non-dumpable tasks owned by some root */ |
| if (mm) { |
| if (get_dumpable(mm) != SUID_DUMP_USER) { |
| struct user_namespace *user_ns = mm->user_ns; |
| |
| uid = make_kuid(user_ns, 0); |
| if (!uid_valid(uid)) |
| uid = GLOBAL_ROOT_UID; |
| |
| gid = make_kgid(user_ns, 0); |
| if (!gid_valid(gid)) |
| gid = GLOBAL_ROOT_GID; |
| } |
| } else { |
| uid = GLOBAL_ROOT_UID; |
| gid = GLOBAL_ROOT_GID; |
| } |
| task_unlock(task); |
| } |
| *ruid = uid; |
| *rgid = gid; |
| } |
| |
| struct inode *proc_pid_make_inode(struct super_block * sb, |
| struct task_struct *task, umode_t mode) |
| { |
| struct inode * inode; |
| struct proc_inode *ei; |
| |
| /* We need a new inode */ |
| |
| inode = new_inode(sb); |
| if (!inode) |
| goto out; |
| |
| /* Common stuff */ |
| ei = PROC_I(inode); |
| inode->i_mode = mode; |
| inode->i_ino = get_next_ino(); |
| inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); |
| inode->i_op = &proc_def_inode_operations; |
| |
| /* |
| * grab the reference to task. |
| */ |
| ei->pid = get_task_pid(task, PIDTYPE_PID); |
| if (!ei->pid) |
| goto out_unlock; |
| |
| task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); |
| security_task_to_inode(task, inode); |
| |
| out: |
| return inode; |
| |
| out_unlock: |
| iput(inode); |
| return NULL; |
| } |
| |
| int pid_getattr(const struct path *path, struct kstat *stat, |
| u32 request_mask, unsigned int query_flags) |
| { |
| struct inode *inode = d_inode(path->dentry); |
| struct pid_namespace *pid = proc_pid_ns(inode); |
| struct task_struct *task; |
| |
| generic_fillattr(inode, stat); |
| |
| stat->uid = GLOBAL_ROOT_UID; |
| stat->gid = GLOBAL_ROOT_GID; |
| rcu_read_lock(); |
| task = pid_task(proc_pid(inode), PIDTYPE_PID); |
| if (task) { |
| if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) { |
| rcu_read_unlock(); |
| /* |
| * This doesn't prevent learning whether PID exists, |
| * it only makes getattr() consistent with readdir(). |
| */ |
| return -ENOENT; |
| } |
| task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); |
| } |
| rcu_read_unlock(); |
| return 0; |
| } |
| |
| /* dentry stuff */ |
| |
| /* |
| * Set <pid>/... inode ownership (can change due to setuid(), etc.) |
| */ |
| void pid_update_inode(struct task_struct *task, struct inode *inode) |
| { |
| task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid); |
| |
| inode->i_mode &= ~(S_ISUID | S_ISGID); |
| security_task_to_inode(task, inode); |
| } |
| |
| /* |
| * Rewrite the inode's ownerships here because the owning task may have |
| * performed a setuid(), etc. |
| * |
| */ |
| static int pid_revalidate(struct dentry *dentry, unsigned int flags) |
| { |
| struct inode *inode; |
| struct task_struct *task; |
| |
| if (flags & LOOKUP_RCU) |
| return -ECHILD; |
| |
| inode = d_inode(dentry); |
| task = get_proc_task(inode); |
| |
| if (task) { |
| pid_update_inode(task, inode); |
| put_task_struct(task); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline bool proc_inode_is_dead(struct inode *inode) |
| { |
| return !proc_pid(inode)->tasks[PIDTYPE_PID].first; |
| } |
| |
| int pid_delete_dentry(const struct dentry *dentry) |
| { |
| /* Is the task we represent dead? |
| * If so, then don't put the dentry on the lru list, |
| * kill it immediately. |
| */ |
| return proc_inode_is_dead(d_inode(dentry)); |
| } |
| |
| const struct dentry_operations pid_dentry_operations = |
| { |
| .d_revalidate = pid_revalidate, |
| .d_delete = pid_delete_dentry, |
| }; |
| |
| /* Lookups */ |
| |
| /* |
| * Fill a directory entry. |
| * |
| * If possible create the dcache entry and derive our inode number and |
| * file type from dcache entry. |
| * |
| * Since all of the proc inode numbers are dynamically generated, the inode |
| * numbers do not exist until the inode is cache. This means creating the |
| * the dcache entry in readdir is necessary to keep the inode numbers |
| * reported by readdir in sync with the inode numbers reported |
| * by stat. |
| */ |
| bool proc_fill_cache(struct file *file, struct dir_context *ctx, |
| const char *name, unsigned int len, |
| instantiate_t instantiate, struct task_struct *task, const void *ptr) |
| { |
| struct dentry *child, *dir = file->f_path.dentry; |
| struct qstr qname = QSTR_INIT(name, len); |
| struct inode *inode; |
| unsigned type = DT_UNKNOWN; |
| ino_t ino = 1; |
| |
| child = d_hash_and_lookup(dir, &qname); |
| if (!child) { |
| DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); |
| child = d_alloc_parallel(dir, &qname, &wq); |
| if (IS_ERR(child)) |
| goto end_instantiate; |
| if (d_in_lookup(child)) { |
| struct dentry *res; |
| res = instantiate(child, task, ptr); |
| d_lookup_done(child); |
| if (unlikely(res)) { |
| dput(child); |
| child = res; |
| if (IS_ERR(child)) |
| goto end_instantiate; |
| } |
| } |
| } |
| inode = d_inode(child); |
| ino = inode->i_ino; |
| type = inode->i_mode >> 12; |
| dput(child); |
| end_instantiate: |
| return dir_emit(ctx, name, len, ino, type); |
| } |
| |
| /* |
| * dname_to_vma_addr - maps a dentry name into two unsigned longs |
| * which represent vma start and end addresses. |
| */ |
| static int dname_to_vma_addr(struct dentry *dentry, |
| unsigned long *start, unsigned long *end) |
| { |
| const char *str = dentry->d_name.name; |
| unsigned long long sval, eval; |
| unsigned int len; |
| |
| if (str[0] == '0' && str[1] != '-') |
| return -EINVAL; |
| len = _parse_integer(str, 16, &sval); |
| if (len & KSTRTOX_OVERFLOW) |
| return -EINVAL; |
| if (sval != (unsigned long)sval) |
| return -EINVAL; |
| str += len; |
| |
| if (*str != '-') |
| return -EINVAL; |
| str++; |
| |
| if (str[0] == '0' && str[1]) |
| return -EINVAL; |
| len = _parse_integer(str, 16, &eval); |
| if (len & KSTRTOX_OVERFLOW) |
| return -EINVAL; |
| if (eval != (unsigned long)eval) |
| return -EINVAL; |
| str += len; |
| |
| if (*str != '\0') |
| return -EINVAL; |
| |
| *start = sval; |
| *end = eval; |
| |
| return 0; |
| } |
| |
| static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) |
| { |
| unsigned long vm_start, vm_end; |
| bool exact_vma_exists = false; |
| struct mm_struct *mm = NULL; |
| struct task_struct *task; |
| struct inode *inode; |
| int status = 0; |
| |
| if (flags & LOOKUP_RCU) |
| return -ECHILD; |
| |
| inode = d_inode(dentry); |
| task = get_proc_task(inode); |
| if (!task) |
| goto out_notask; |
| |
| mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); |
| if (IS_ERR_OR_NULL(mm)) |
| goto out; |
| |
| if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { |
| down_read(&mm->mmap_sem); |
| exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); |
| up_read(&mm->mmap_sem); |
| } |
| |
| mmput(mm); |
| |
| if (exact_vma_exists) { |
| task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); |
| |
| security_task_to_inode(task, inode); |
| status = 1; |
| } |
| |
| out: |
| put_task_struct(task); |
| |
| out_notask: |
| return status; |
| } |
| |
| static const struct dentry_operations tid_map_files_dentry_operations = { |
| .d_revalidate = map_files_d_revalidate, |
| .d_delete = pid_delete_dentry, |
| }; |
| |
| static int map_files_get_link(struct dentry *dentry, struct path *path) |
| { |
| unsigned long vm_start, vm_end; |
| struct vm_area_struct *vma; |
| struct task_struct *task; |
| struct mm_struct *mm; |
| int rc; |
| |
| rc = -ENOENT; |
| task = get_proc_task(d_inode(dentry)); |
| if (!task) |
| goto out; |
| |
| mm = get_task_mm(task); |
| put_task_struct(task); |
| if (!mm) |
| goto out; |
| |
| rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); |
| if (rc) |
| goto out_mmput; |
| |
| rc = -ENOENT; |
| down_read(&mm->mmap_sem); |
| vma = find_exact_vma(mm, vm_start, vm_end); |
| if (vma && vma->vm_file) { |
| *path = vma->vm_file->f_path; |
| path_get(path); |
| rc = 0; |
| } |
| up_read(&mm->mmap_sem); |
| |
| out_mmput: |
| mmput(mm); |
| out: |
| return rc; |
| } |
| |
| struct map_files_info { |
| unsigned long start; |
| unsigned long end; |
| fmode_t mode; |
| }; |
| |
| /* |
| * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the |
| * symlinks may be used to bypass permissions on ancestor directories in the |
| * path to the file in question. |
| */ |
| static const char * |
| proc_map_files_get_link(struct dentry *dentry, |
| struct inode *inode, |
| struct delayed_call *done) |
| { |
| if (!capable(CAP_SYS_ADMIN)) |
| return ERR_PTR(-EPERM); |
| |
| return proc_pid_get_link(dentry, inode, done); |
| } |
| |
| /* |
| * Identical to proc_pid_link_inode_operations except for get_link() |
| */ |
| static const struct inode_operations proc_map_files_link_inode_operations = { |
| .readlink = proc_pid_readlink, |
| .get_link = proc_map_files_get_link, |
| .setattr = proc_setattr, |
| }; |
| |
| static struct dentry * |
| proc_map_files_instantiate(struct dentry *dentry, |
| struct task_struct *task, const void *ptr) |
| { |
| fmode_t mode = (fmode_t)(unsigned long)ptr; |
| struct proc_inode *ei; |
| struct inode *inode; |
| |
| inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK | |
| ((mode & FMODE_READ ) ? S_IRUSR : 0) | |
| ((mode & FMODE_WRITE) ? S_IWUSR : 0)); |
| if (!inode) |
| return ERR_PTR(-ENOENT); |
| |
| ei = PROC_I(inode); |
| ei->op.proc_get_link = map_files_get_link; |
| |
| inode->i_op = &proc_map_files_link_inode_operations; |
| inode->i_size = 64; |
| |
| d_set_d_op(dentry, &tid_map_files_dentry_operations); |
| return d_splice_alias(inode, dentry); |
| } |
| |
| static struct dentry *proc_map_files_lookup(struct inode *dir, |
| struct dentry *dentry, unsigned int flags) |
| { |
| unsigned long vm_start, vm_end; |
| struct vm_area_struct *vma; |
| struct task_struct *task; |
| struct dentry *result; |
| struct mm_struct *mm; |
| |
| result = ERR_PTR(-ENOENT); |
| task = get_proc_task(dir); |
| if (!task) |
| goto out; |
| |
| result = ERR_PTR(-EACCES); |
| if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) |
| goto out_put_task; |
| |
| result = ERR_PTR(-ENOENT); |
| if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) |
| goto out_put_task; |
| |
| mm = get_task_mm(task); |
| if (!mm) |
| goto out_put_task; |
| |
| down_read(&mm->mmap_sem); |
| vma = find_exact_vma(mm, vm_start, vm_end); |
| if (!vma) |
| goto out_no_vma; |
| |
| if (vma->vm_file) |
| result = proc_map_files_instantiate(dentry, task, |
| (void *)(unsigned long)vma->vm_file->f_mode); |
| |
| out_no_vma: |
| up_read(&mm->mmap_sem); |
| mmput(mm); |
| out_put_task: |
| put_task_struct(task); |
| out: |
| return result; |
| } |
| |
| static const struct inode_operations proc_map_files_inode_operations = { |
| .lookup = proc_map_files_lookup, |
| .permission = proc_fd_permission, |
| .setattr = proc_setattr, |
| }; |
| |
| static int |
| proc_map_files_readdir(struct file *file, struct dir_context *ctx) |
| { |
| struct vm_area_struct *vma; |
| struct task_struct *task; |
| struct mm_struct *mm; |
| unsigned long nr_files, pos, i; |
| struct flex_array *fa = NULL; |
| struct map_files_info info; |
| struct map_files_info *p; |
| int ret; |
| |
| ret = -ENOENT; |
| task = get_proc_task(file_inode(file)); |
| if (!task) |
| goto out; |
| |
| ret = -EACCES; |
| if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) |
| goto out_put_task; |
| |
| ret = 0; |
| if (!dir_emit_dots(file, ctx)) |
| goto out_put_task; |
| |
| mm = get_task_mm(task); |
| if (!mm) |
| goto out_put_task; |
| down_read(&mm->mmap_sem); |
| |
| nr_files = 0; |
| |
| /* |
| * We need two passes here: |
| * |
| * 1) Collect vmas of mapped files with mmap_sem taken |
| * 2) Release mmap_sem and instantiate entries |
| * |
| * otherwise we get lockdep complained, since filldir() |
| * routine might require mmap_sem taken in might_fault(). |
| */ |
| |
| for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { |
| if (vma->vm_file && ++pos > ctx->pos) |
| nr_files++; |
| } |
| |
| if (nr_files) { |
| fa = flex_array_alloc(sizeof(info), nr_files, |
| GFP_KERNEL); |
| if (!fa || flex_array_prealloc(fa, 0, nr_files, |
| GFP_KERNEL)) { |
| ret = -ENOMEM; |
| if (fa) |
| flex_array_free(fa); |
| up_read(&mm->mmap_sem); |
| mmput(mm); |
| goto out_put_task; |
| } |
| for (i = 0, vma = mm->mmap, pos = 2; vma; |
| vma = vma->vm_next) { |
| if (!vma->vm_file) |
| continue; |
| if (++pos <= ctx->pos) |
| continue; |
| |
| info.start = vma->vm_start; |
| info.end = vma->vm_end; |
| info.mode = vma->vm_file->f_mode; |
| if (flex_array_put(fa, i++, &info, GFP_KERNEL)) |
| BUG(); |
| } |
| } |
| up_read(&mm->mmap_sem); |
| mmput(mm); |
| |
| for (i = 0; i < nr_files; i++) { |
| char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */ |
| unsigned int len; |
| |
| p = flex_array_get(fa, i); |
| len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end); |
| if (!proc_fill_cache(file, ctx, |
| buf, len, |
| proc_map_files_instantiate, |
| task, |
| (void *)(unsigned long)p->mode)) |
| break; |
| ctx->pos++; |
| } |
| if (fa) |
| flex_array_free(fa); |
| |
| out_put_task: |
| put_task_struct(task); |
| out: |
| return ret; |
| } |
| |
| static const struct file_operations proc_map_files_operations = { |
| .read = generic_read_dir, |
| .iterate_shared = proc_map_files_readdir, |
| .llseek = generic_file_llseek, |
| }; |
| |
| #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) |
| struct timers_private { |
| struct pid *pid; |
| struct task_struct *task; |
| struct sighand_struct *sighand; |
| struct pid_namespace *ns; |
| unsigned long flags; |
| }; |
| |
| static void *timers_start(struct seq_file *m, loff_t *pos) |
| { |
| struct timers_private *tp = m->private; |
| |
| tp->task = get_pid_task(tp->pid, PIDTYPE_PID); |
| if (!tp->task) |
| return ERR_PTR(-ESRCH); |
| |
| tp->sighand = lock_task_sighand(tp->task, &tp->flags); |
| if (!tp->sighand) |
| return ERR_PTR(-ESRCH); |
| |
| return seq_list_start(&tp->task->signal->posix_timers, *pos); |
| } |
| |
| static void *timers_next(struct seq_file *m, void *v, loff_t *pos) |
| { |
| struct timers_private *tp = m->private; |
| return seq_list_next(v, &tp->task->signal->posix_timers, pos); |
| } |
| |
| static void timers_stop(struct seq_file *m, void *v) |
| { |
| struct timers_private *tp = m->private; |
| |
| if (tp->sighand) { |
| unlock_task_sighand(tp->task, &tp->flags); |
| tp->sighand = NULL; |
| } |
| |
| if (tp->task) { |
| put_task_struct(tp->task); |
| tp->task = NULL; |
| } |
| } |
| |
| static int show_timer(struct seq_file *m, void *v) |
| { |
| struct k_itimer *timer; |
| struct timers_private *tp = m->private; |
| int notify; |
| static const char * const nstr[] = { |
| [SIGEV_SIGNAL] = "signal", |
| [SIGEV_NONE] = "none", |
| [SIGEV_THREAD] = "thread", |
| }; |
| |
| timer = list_entry((struct list_head *)v, struct k_itimer, list); |
| notify = timer->it_sigev_notify; |
| |
| seq_printf(m, "ID: %d\n", timer->it_id); |
| seq_printf(m, "signal: %d/%px\n", |
| timer->sigq->info.si_signo, |
| timer->sigq->info.si_value.sival_ptr); |
| seq_printf(m, "notify: %s/%s.%d\n", |
| nstr[notify & ~SIGEV_THREAD_ID], |
| (notify & SIGEV_THREAD_ID) ? "tid" : "pid", |
| pid_nr_ns(timer->it_pid, tp->ns)); |
| seq_printf(m, "ClockID: %d\n", timer->it_clock); |
| |
| return 0; |
| } |
| |
| static const struct seq_operations proc_timers_seq_ops = { |
| .start = timers_start, |
| .next = timers_next, |
| .stop = timers_stop, |
| .show = show_timer, |
| }; |
| |
| static int proc_timers_open(struct inode *inode, struct file *file) |
| { |
| struct timers_private *tp; |
| |
| tp = __seq_open_private(file, &proc_timers_seq_ops, |
| sizeof(struct timers_private)); |
| if (!tp) |
| return -ENOMEM; |
| |
| tp->pid = proc_pid(inode); |
| tp->ns = proc_pid_ns(inode); |
| return 0; |
| } |
| |
| static const struct file_operations proc_timers_operations = { |
| .open = proc_timers_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release_private, |
| }; |
| #endif |
| |
| static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, |
| size_t count, loff_t *offset) |
| { |
| struct inode *inode = file_inode(file); |
| struct task_struct *p; |
| u64 slack_ns; |
| int err; |
| |
| err = kstrtoull_from_user(buf, count, 10, &slack_ns); |
| if (err < 0) |
| return err; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| |
| if (p != current) { |
| if (!capable(CAP_SYS_NICE)) { |
| count = -EPERM; |
| goto out; |
| } |
| |
| err = security_task_setscheduler(p); |
| if (err) { |
| count = err; |
| goto out; |
| } |
| } |
| |
| task_lock(p); |
| if (slack_ns == 0) |
| p->timer_slack_ns = p->default_timer_slack_ns; |
| else |
| p->timer_slack_ns = slack_ns; |
| task_unlock(p); |
| |
| out: |
| put_task_struct(p); |
| |
| return count; |
| } |
| |
| static int timerslack_ns_show(struct seq_file *m, void *v) |
| { |
| struct inode *inode = m->private; |
| struct task_struct *p; |
| int err = 0; |
| |
| p = get_proc_task(inode); |
| if (!p) |
| return -ESRCH; |
| |
| if (p != current) { |
| |
| if (!capable(CAP_SYS_NICE)) { |
| err = -EPERM; |
| goto out; |
| } |
| err = security_task_getscheduler(p); |
| if (err) |
| goto out; |
| } |
| |
| task_lock(p); |
| seq_printf(m, "%llu\n", p->timer_slack_ns); |
| task_unlock(p); |
| |
| out: |
| put_task_struct(p); |
| |
| return err; |
| } |
| |
| static int timerslack_ns_open(struct inode *inode, struct file *filp) |
| { |
| return single_open(filp, timerslack_ns_show, inode); |
| } |
| |
| static const struct file_operations proc_pid_set_timerslack_ns_operations = { |
| .open = timerslack_ns_open, |
| .read = seq_read, |
| .write = timerslack_ns_write, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static struct dentry *proc_pident_instantiate(struct dentry *dentry, |
| struct task_struct *task, const void *ptr) |
| { |
| const struct pid_entry *p = ptr; |
| struct inode *inode; |
| struct proc_inode *ei; |
| |
| inode = proc_pid_make_inode(dentry->d_sb, task, p->mode); |
| if (!inode) |
| return ERR_PTR(-ENOENT); |
| |
| ei = PROC_I(inode); |
| if (S_ISDIR(inode->i_mode)) |
| set_nlink(inode, 2); /* Use getattr to fix if necessary */ |
| if (p->iop) |
| inode->i_op = p->iop; |
| if (p->fop) |
| inode->i_fop = p->fop; |
| ei->op = p->op; |
| pid_update_inode(task, inode); |
| d_set_d_op(dentry, &pid_dentry_operations); |
| return d_splice_alias(inode, dentry); |
| } |
| |
| static struct dentry *proc_pident_lookup(struct inode *dir, |
| struct dentry *dentry, |
| const struct pid_entry *ents, |
| unsigned int nents) |
| { |
| struct task_struct *task = get_proc_task(dir); |
| const struct pid_entry *p, *last; |
| struct dentry *res = ERR_PTR(-ENOENT); |
| |
| if (!task) |
| goto out_no_task; |
| |
| /* |
| * Yes, it does not scale. And it should not. Don't add |
| * new entries into /proc/<tgid>/ without very good reasons. |
| */ |
| last = &ents[nents]; |
| for (p = ents; p < last; p++) { |
| if (p->len != dentry->d_name.len) |
| continue; |
| if (!memcmp(dentry->d_name.name, p->name, p->len)) { |
| res = proc_pident_instantiate(dentry, task, p); |
| break; |
| } |
| } |
| put_task_struct(task); |
| out_no_task: |
| return res; |
| } |
| |
| static int proc_pident_readdir(struct file *file, struct dir_context *ctx, |
| const struct pid_entry *ents, unsigned int nents) |
| { |
| struct task_struct *task = get_proc_task(file_inode(file)); |
| const struct pid_entry *p; |
| |
| if (!task) |
| return -ENOENT; |
| |
| if (!dir_emit_dots(file, ctx)) |
| goto out; |
| |
| if (ctx->pos >= nents + 2) |
| goto out; |
| |
| for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { |
| if (!proc_fill_cache(file, ctx, p->name, p->len, |
| proc_pident_instantiate, task, p)) |
| break; |
| ctx->pos++; |
| } |
| out: |
| put_task_struct(task); |
| return 0; |
| } |
| |
| #ifdef CONFIG_SECURITY |
| static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, |
| size_t count, loff_t *ppos) |
| { |
| struct inode * inode = file_inode(file); |
| char *p = NULL; |
| ssize_t length; |
| struct task_struct *task = get_proc_task(inode); |
| |
| if (!task) |
| return -ESRCH; |
| |
| length = security_getprocattr(task, |
| (char*)file->f_path.dentry->d_name.name, |
| &p); |
| put_task_struct(task); |
| if (length > 0) |
| length = simple_read_from_buffer(buf, count, ppos, p, length); |
| kfree(p); |
| return length; |
| } |
| |
| static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, |
| size_t count, loff_t *ppos) |
| { |
| struct inode * inode = file_inode(file); |
| struct task_struct *task; |
| void *page; |
| int rv; |
| |
| rcu_read_lock(); |
| task = pid_task(proc_pid(inode), PIDTYPE_PID); |
| if (!task) { |
| rcu_read_unlock(); |
| return -ESRCH; |
| } |
| /* A task may only write its own attributes. */ |
| if (current != task) { |
| rcu_read_unlock(); |
| return -EACCES; |
| } |
| rcu_read_unlock(); |
| |
| if (count > PAGE_SIZE) |
| count = PAGE_SIZE; |
| |
| /* No partial writes. */ |
| if (*ppos != 0) |
| return -EINVAL; |
| |
| page = memdup_user(buf, count); |
| if (IS_ERR(page)) { |
| rv = PTR_ERR(page); |
| goto out; |
| } |
| |
| /* Guard against adverse ptrace interaction */ |
| rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); |
| if (rv < 0) |
| goto out_free; |
| |
| rv = security_setprocattr(file->f_path.dentry->d_name.name, page, count); |
| mutex_unlock(¤t->signal->cred_guard_mutex); |
| out_free: |
| kfree(page); |
| out: |
| return rv; |
| } |
| |
| static const struct file_operations proc_pid_attr_operations = { |
| .read = proc_pid_attr_read, |
| .write = proc_pid_attr_write, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static const struct pid_entry attr_dir_stuff[] = { |
| REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), |
| REG("prev", S_IRUGO, proc_pid_attr_operations), |
| REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), |
| REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), |
| REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), |
| REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), |
| }; |
| |
| static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) |
| { |
| return proc_pident_readdir(file, ctx, |
| attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); |
| } |
| |
| static const struct file_operations proc_attr_dir_operations = { |
| .read = generic_read_dir, |
| .iterate_shared = proc_attr_dir_readdir, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static struct dentry *proc_attr_dir_lookup(struct inode *dir, |
| struct dentry *dentry, unsigned int flags) |
| { |
| return proc_pident_lookup(dir, dentry, |
| attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); |
| } |
| |
| static const struct inode_operations proc_attr_dir_inode_operations = { |
| .lookup = proc_attr_dir_lookup, |
| .getattr = pid_getattr, |
| .setattr = proc_setattr, |
| }; |
| |
| #endif |
| |
| #ifdef CONFIG_ELF_CORE |
| static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct task_struct *task = get_proc_task(file_inode(file)); |
| struct mm_struct *mm; |
| char buffer[PROC_NUMBUF]; |
| size_t len; |
| int ret; |
| |
| if (!task) |
| return -ESRCH; |
| |
| ret = 0; |
| mm = get_task_mm(task); |
| if (mm) { |
| len = snprintf(buffer, sizeof(buffer), "%08lx\n", |
| ((mm->flags & MMF_DUMP_FILTER_MASK) >> |
| MMF_DUMP_FILTER_SHIFT)); |
| mmput(mm); |
| ret = simple_read_from_buffer(buf, count, ppos, buffer, len); |
| } |
| |
| put_task_struct(task); |
| |
| return ret; |
| } |
| |
| static ssize_t proc_coredump_filter_write(struct file *file, |
| const char __user *buf, |
| size_t count, |
| loff_t *ppos) |
| { |
| struct task_struct *task; |
| struct mm_struct *mm; |
| unsigned int val; |
| int ret; |
| int i; |
| unsigned long mask; |
| |
| ret = kstrtouint_from_user(buf, count, 0, &val); |
| if (ret < 0) |
| return ret; |
| |
| ret = -ESRCH; |
| task = get_proc_task(file_inode(file)); |
| if (!task) |
| goto out_no_task; |
| |
| mm = get_task_mm(task); |
| if (!mm) |
| goto out_no_mm; |
| ret = 0; |
| |
| for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { |
| if (val & mask) |
| set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); |
| else |
| clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); |
| } |
| |
| mmput(mm); |
| out_no_mm: |
| put_task_struct(task); |
| out_no_task: |
| if (ret < 0) |
| return ret; |
| return count; |
| } |
| |
| static const struct file_operations proc_coredump_filter_operations = { |
| .read = proc_coredump_filter_read, |
| .write = proc_coredump_filter_write, |
| .llseek = generic_file_llseek, |
| }; |
| #endif |
| |
| #ifdef CONFIG_TASK_IO_ACCOUNTING |
| static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) |
| { |
| struct task_io_accounting acct = task->ioac; |
| unsigned long flags; |
| int result; |
| |
| result = mutex_lock_killable(&task->signal->cred_guard_mutex); |
| if (result) |
| return result; |
| |
| if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { |
| result = -EACCES; |
| goto out_unlock; |
| } |
| |
| if (whole && lock_task_sighand(task, &flags)) { |
| struct task_struct *t = task; |
| |
| task_io_accounting_add(&acct, &task->signal->ioac); |
| while_each_thread(task, t) |
| task_io_accounting_add(&acct, &t->ioac); |
| |
| unlock_task_sighand(task, &flags); |
| } |
| seq_printf(m, |
| "rchar: %llu\n" |
| "wchar: %llu\n" |
| "syscr: %llu\n" |
| "syscw: %llu\n" |
| "read_bytes: %llu\n" |
| "write_bytes: %llu\n" |
| "cancelled_write_bytes: %llu\n", |
| (unsigned long long)acct.rchar, |
| (unsigned long long)acct.wchar, |
| (unsigned long long)acct.syscr, |
| (unsigned long long)acct.syscw, |
| (unsigned long long)acct.read_bytes, |
| (unsigned long long)acct.write_bytes, |
| (unsigned long long)acct.cancelled_write_bytes); |
| result = 0; |
| |
| out_unlock: |
| mutex_unlock(&task->signal->cred_guard_mutex); |
| return result; |
| } |
| |
| static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| return do_io_accounting(task, m, 0); |
| } |
| |
| static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| return do_io_accounting(task, m, 1); |
| } |
| #endif /* CONFIG_TASK_IO_ACCOUNTING */ |
| |
| #ifdef CONFIG_USER_NS |
| static int proc_id_map_open(struct inode *inode, struct file *file, |
| const struct seq_operations *seq_ops) |
| { |
| struct user_namespace *ns = NULL; |
| struct task_struct *task; |
| struct seq_file *seq; |
| int ret = -EINVAL; |
| |
| task = get_proc_task(inode); |
| if (task) { |
| rcu_read_lock(); |
| ns = get_user_ns(task_cred_xxx(task, user_ns)); |
| rcu_read_unlock(); |
| put_task_struct(task); |
| } |
| if (!ns) |
| goto err; |
| |
| ret = seq_open(file, seq_ops); |
| if (ret) |
| goto err_put_ns; |
| |
| seq = file->private_data; |
| seq->private = ns; |
| |
| return 0; |
| err_put_ns: |
| put_user_ns(ns); |
| err: |
| return ret; |
| } |
| |
| static int proc_id_map_release(struct inode *inode, struct file *file) |
| { |
| struct seq_file *seq = file->private_data; |
| struct user_namespace *ns = seq->private; |
| put_user_ns(ns); |
| return seq_release(inode, file); |
| } |
| |
| static int proc_uid_map_open(struct inode *inode, struct file *file) |
| { |
| return proc_id_map_open(inode, file, &proc_uid_seq_operations); |
| } |
| |
| static int proc_gid_map_open(struct inode *inode, struct file *file) |
| { |
| return proc_id_map_open(inode, file, &proc_gid_seq_operations); |
| } |
| |
| static int proc_projid_map_open(struct inode *inode, struct file *file) |
| { |
| return proc_id_map_open(inode, file, &proc_projid_seq_operations); |
| } |
| |
| static const struct file_operations proc_uid_map_operations = { |
| .open = proc_uid_map_open, |
| .write = proc_uid_map_write, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = proc_id_map_release, |
| }; |
| |
| static const struct file_operations proc_gid_map_operations = { |
| .open = proc_gid_map_open, |
| .write = proc_gid_map_write, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = proc_id_map_release, |
| }; |
| |
| static const struct file_operations proc_projid_map_operations = { |
| .open = proc_projid_map_open, |
| .write = proc_projid_map_write, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = proc_id_map_release, |
| }; |
| |
| static int proc_setgroups_open(struct inode *inode, struct file *file) |
| { |
| struct user_namespace *ns = NULL; |
| struct task_struct *task; |
| int ret; |
| |
| ret = -ESRCH; |
| task = get_proc_task(inode); |
| if (task) { |
| rcu_read_lock(); |
| ns = get_user_ns(task_cred_xxx(task, user_ns)); |
| rcu_read_unlock(); |
| put_task_struct(task); |
| } |
| if (!ns) |
| goto err; |
| |
| if (file->f_mode & FMODE_WRITE) { |
| ret = -EACCES; |
| if (!ns_capable(ns, CAP_SYS_ADMIN)) |
| goto err_put_ns; |
| } |
| |
| ret = single_open(file, &proc_setgroups_show, ns); |
| if (ret) |
| goto err_put_ns; |
| |
| return 0; |
| err_put_ns: |
| put_user_ns(ns); |
| err: |
| return ret; |
| } |
| |
| static int proc_setgroups_release(struct inode *inode, struct file *file) |
| { |
| struct seq_file *seq = file->private_data; |
| struct user_namespace *ns = seq->private; |
| int ret = single_release(inode, file); |
| put_user_ns(ns); |
| return ret; |
| } |
| |
| static const struct file_operations proc_setgroups_operations = { |
| .open = proc_setgroups_open, |
| .write = proc_setgroups_write, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = proc_setgroups_release, |
| }; |
| #endif /* CONFIG_USER_NS */ |
| |
| static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| int err = lock_trace(task); |
| if (!err) { |
| seq_printf(m, "%08x\n", task->personality); |
| unlock_trace(task); |
| } |
| return err; |
| } |
| |
| #ifdef CONFIG_LIVEPATCH |
| static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, |
| struct pid *pid, struct task_struct *task) |
| { |
| seq_printf(m, "%d\n", task->patch_state); |
| return 0; |
| } |
| #endif /* CONFIG_LIVEPATCH */ |
| |
| /* |
| * Thread groups |
| */ |
| static const struct file_operations proc_task_operations; |
| static const struct inode_operations proc_task_inode_operations; |
| |
| static const struct pid_entry tgid_base_stuff[] = { |
| DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), |
| DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), |
| DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), |
| DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), |
| DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), |
| #ifdef CONFIG_NET |
| DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), |
| #endif |
| REG("environ", S_IRUSR, proc_environ_operations), |
| REG("auxv", S_IRUSR, proc_auxv_operations), |
| ONE("status", S_IRUGO, proc_pid_status), |
| ONE("personality", S_IRUSR, proc_pid_personality), |
| ONE("limits", S_IRUGO, proc_pid_limits), |
| #ifdef CONFIG_SCHED_DEBUG |
| REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), |
| #endif |
| #ifdef CONFIG_SCHED_AUTOGROUP |
| REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), |
| #endif |
| REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), |
| #ifdef CONFIG_HAVE_ARCH_TRACEHOOK |
| ONE("syscall", S_IRUSR, proc_pid_syscall), |
| #endif |
| REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), |
| ONE("stat", S_IRUGO, proc_tgid_stat), |
| ONE("statm", S_IRUGO, proc_pid_statm), |
| REG("maps", S_IRUGO, proc_pid_maps_operations), |
| #ifdef CONFIG_NUMA |
| REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), |
| #endif |
| REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), |
| LNK("cwd", proc_cwd_link), |
| LNK("root", proc_root_link), |
| LNK("exe", proc_exe_link), |
| REG("mounts", S_IRUGO, proc_mounts_operations), |
| REG("mountinfo", S_IRUGO, proc_mountinfo_operations), |
| REG("mountstats", S_IRUSR, proc_mountstats_operations), |
| #ifdef CONFIG_PROC_PAGE_MONITOR |
| REG("clear_refs", S_IWUSR, proc_clear_refs_operations), |
| REG("smaps", S_IRUGO, proc_pid_smaps_operations), |
| REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), |
| REG("pagemap", S_IRUSR, proc_pagemap_operations), |
| #endif |
| #ifdef CONFIG_SECURITY |
| DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), |
| #endif |
| #ifdef CONFIG_KALLSYMS |
| ONE("wchan", S_IRUGO, proc_pid_wchan), |
| #endif |
| #ifdef CONFIG_STACKTRACE |
| ONE("stack", S_IRUSR, proc_pid_stack), |
| #endif |
| #ifdef CONFIG_SCHED_INFO |
| ONE("schedstat", S_IRUGO, proc_pid_schedstat), |
| #endif |
| #ifdef CONFIG_LATENCYTOP |
| REG("latency", S_IRUGO, proc_lstats_operations), |
| #endif |
| #ifdef CONFIG_PROC_PID_CPUSET |
| ONE("cpuset", S_IRUGO, proc_cpuset_show), |
| #endif |
| #ifdef CONFIG_CGROUPS |
| ONE("cgroup", S_IRUGO, proc_cgroup_show), |
| #endif |
| ONE("oom_score", S_IRUGO, proc_oom_score), |
| REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), |
| REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), |
| #ifdef CONFIG_AUDITSYSCALL |
| REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), |
| REG("sessionid", S_IRUGO, proc_sessionid_operations), |
| #endif |
| #ifdef CONFIG_FAULT_INJECTION |
| REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), |
| REG("fail-nth", 0644, proc_fail_nth_operations), |
| #endif |
| #ifdef CONFIG_ELF_CORE |
| REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), |
| #endif |
| #ifdef CONFIG_TASK_IO_ACCOUNTING |
| ONE("io", S_IRUSR, proc_tgid_io_accounting), |
| #endif |
| #ifdef CONFIG_USER_NS |
| REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), |
| REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), |
| REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), |
| REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), |
| #endif |
| #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) |
| REG("timers", S_IRUGO, proc_timers_operations), |
| #endif |
| REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), |
| #ifdef CONFIG_LIVEPATCH |
| ONE("patch_state", S_IRUSR, proc_pid_patch_state), |
| #endif |
| }; |
| |
| static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) |
| { |
| return proc_pident_readdir(file, ctx, |
| tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); |
| } |
| |
| static const struct file_operations proc_tgid_base_operations = { |
| .read = generic_read_dir, |
| .iterate_shared = proc_tgid_base_readdir, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) |
| { |
| return proc_pident_lookup(dir, dentry, |
| tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); |
| } |
| |
| static const struct inode_operations proc_tgid_base_inode_operations = { |
| .lookup = proc_tgid_base_lookup, |
| .getattr = pid_getattr, |
| .setattr = proc_setattr, |
| .permission = proc_pid_permission, |
| }; |
| |
| static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) |
| { |
| struct dentry *dentry, *leader, *dir; |
| char buf[10 + 1]; |
| struct qstr name; |
| |
| name.name = buf; |
| name.len = snprintf(buf, sizeof(buf), "%u", pid); |
| /* no ->d_hash() rejects on procfs */ |
| dentry = d_hash_and_lookup(mnt->mnt_root, &name); |
| if (dentry) { |
| d_invalidate(dentry); |
| dput(dentry); |
| } |
| |
| if (pid == tgid) |
| return; |
| |
| name.name = buf; |
| name.len = snprintf(buf, sizeof(buf), "%u", tgid); |
| leader = d_hash_and_lookup(mnt->mnt_root, &name); |
| if (!leader) |
| goto out; |
| |
| name.name = "task"; |
| name.len = strlen(name.name); |
| dir = d_hash_and_lookup(leader, &name); |
| if (!dir) |
| goto out_put_leader; |
| |
| name.name = buf; |
|