diff options
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/base.c | 137 | ||||
| -rw-r--r-- | fs/proc/kcore.c | 31 | ||||
| -rw-r--r-- | fs/proc/task_mmu.c | 64 |
3 files changed, 215 insertions, 17 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index d2b8c754f627..0c9ea52ab399 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2240,6 +2240,92 @@ static const struct file_operations proc_timers_operations = { .release = seq_release_private, }; +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 int proc_pident_instantiate(struct inode *dir, struct dentry *dentry, struct task_struct *task, const void *ptr) { @@ -2790,8 +2876,8 @@ static const struct pid_entry tgid_base_stuff[] = { 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), + REG("oom_adj", S_IRUSR, proc_oom_adj_operations), + REG("oom_score_adj", S_IRUSR, proc_oom_score_adj_operations), #ifdef CONFIG_AUDITSYSCALL REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), REG("sessionid", S_IRUGO, proc_sessionid_operations), @@ -2817,6 +2903,7 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_CHECKPOINT_RESTORE REG("timers", S_IRUGO, proc_timers_operations), #endif + REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), }; static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) @@ -3074,6 +3161,44 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx) } /* + * proc_tid_comm_permission is a special permission function exclusively + * used for the node /proc/<pid>/task/<tid>/comm. + * It bypasses generic permission checks in the case where a task of the same + * task group attempts to access the node. + * The rational behind this is that glibc and bionic access this node for + * cross thread naming (pthread_set/getname_np(!self)). However, if + * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, + * which locks out the cross thread naming implementation. + * This function makes sure that the node is always accessible for members of + * same thread group. + */ +static int proc_tid_comm_permission(struct inode *inode, int mask) +{ + bool is_same_tgroup; + struct task_struct *task; + + task = get_proc_task(inode); + if (!task) + return -ESRCH; + is_same_tgroup = same_thread_group(current, task); + put_task_struct(task); + + if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { + /* This file (/proc/<pid>/task/<tid>/comm) can always be + * read or written by the members of the corresponding + * thread group. + */ + return 0; + } + + return generic_permission(inode, mask); +} + +static const struct inode_operations proc_tid_comm_inode_operations = { + .permission = proc_tid_comm_permission, +}; + +/* * Tasks */ static const struct pid_entry tid_base_stuff[] = { @@ -3091,7 +3216,9 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_SCHED_DEBUG REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), #endif - REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), + NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, + &proc_tid_comm_inode_operations, + &proc_pid_set_comm_operations, {}), #ifdef CONFIG_HAVE_ARCH_TRACEHOOK ONE("syscall", S_IRUSR, proc_pid_syscall), #endif @@ -3138,8 +3265,8 @@ static const struct pid_entry tid_base_stuff[] = { 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), + REG("oom_adj", S_IRUSR, proc_oom_adj_operations), + REG("oom_score_adj", S_IRUSR, proc_oom_score_adj_operations), #ifdef CONFIG_AUDITSYSCALL REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), REG("sessionid", S_IRUGO, proc_sessionid_operations), diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index 92e6726f6e37..21f198aa0961 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -430,6 +430,7 @@ static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff) static ssize_t read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos) { + char *buf = file->private_data; ssize_t acc = 0; size_t size, tsz; size_t elf_buflen; @@ -500,23 +501,20 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos) if (clear_user(buffer, tsz)) return -EFAULT; } else if (is_vmalloc_or_module_addr((void *)start)) { - char * elf_buf; - - elf_buf = kzalloc(tsz, GFP_KERNEL); - if (!elf_buf) - return -ENOMEM; - vread(elf_buf, (char *)start, tsz); + vread(buf, (char *)start, tsz); /* we have to zero-fill user buffer even if no read */ - if (copy_to_user(buffer, elf_buf, tsz)) { - kfree(elf_buf); + if (copy_to_user(buffer, buf, tsz)) return -EFAULT; - } - kfree(elf_buf); } else { if (kern_addr_valid(start)) { unsigned long n; - n = copy_to_user(buffer, (char *)start, tsz); + /* + * Using bounce buffer to bypass the + * hardened user copy kernel text checks. + */ + memcpy(buf, (char *) start, tsz); + n = copy_to_user(buffer, buf, tsz); /* * We cannot distinguish between fault on source * and fault on destination. When this happens @@ -549,6 +547,11 @@ static int open_kcore(struct inode *inode, struct file *filp) { if (!capable(CAP_SYS_RAWIO)) return -EPERM; + + filp->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!filp->private_data) + return -ENOMEM; + if (kcore_need_update) kcore_update_ram(); if (i_size_read(inode) != proc_root_kcore->size) { @@ -559,10 +562,16 @@ static int open_kcore(struct inode *inode, struct file *filp) return 0; } +static int release_kcore(struct inode *inode, struct file *file) +{ + kfree(file->private_data); + return 0; +} static const struct file_operations proc_kcore_operations = { .read = read_kcore, .open = open_kcore, + .release = release_kcore, .llseek = default_llseek, }; diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index d598b9c809c1..200e3b29aa22 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -116,6 +116,56 @@ static void release_task_mempolicy(struct proc_maps_private *priv) } #endif +static void seq_print_vma_name(struct seq_file *m, struct vm_area_struct *vma) +{ + const char __user *name = vma_get_anon_name(vma); + struct mm_struct *mm = vma->vm_mm; + + unsigned long page_start_vaddr; + unsigned long page_offset; + unsigned long num_pages; + unsigned long max_len = NAME_MAX; + int i; + + page_start_vaddr = (unsigned long)name & PAGE_MASK; + page_offset = (unsigned long)name - page_start_vaddr; + num_pages = DIV_ROUND_UP(page_offset + max_len, PAGE_SIZE); + + seq_puts(m, "[anon:"); + + for (i = 0; i < num_pages; i++) { + int len; + int write_len; + const char *kaddr; + long pages_pinned; + struct page *page; + + pages_pinned = get_user_pages(current, mm, page_start_vaddr, + 1, 0, 0, &page, NULL); + if (pages_pinned < 1) { + seq_puts(m, "<fault>]"); + return; + } + + kaddr = (const char *)kmap(page); + len = min(max_len, PAGE_SIZE - page_offset); + write_len = strnlen(kaddr + page_offset, len); + seq_write(m, kaddr + page_offset, write_len); + kunmap(page); + put_page(page); + + /* if strnlen hit a null terminator then we're done */ + if (write_len != len) + break; + + max_len -= len; + page_offset = 0; + page_start_vaddr += PAGE_SIZE; + } + + seq_putc(m, ']'); +} + static void vma_stop(struct proc_maps_private *priv) { struct mm_struct *mm = priv->mm; @@ -341,8 +391,14 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid) goto done; } - if (is_stack(priv, vma, is_pid)) + if (is_stack(priv, vma, is_pid)) { name = "[stack]"; + goto done; + } + if (vma_get_anon_name(vma)) { + seq_pad(m, ' '); + seq_print_vma_name(m, vma); + } } done: @@ -667,6 +723,12 @@ static int show_smap(struct seq_file *m, void *v, int is_pid) show_map_vma(m, vma, is_pid); + if (vma_get_anon_name(vma)) { + seq_puts(m, "Name: "); + seq_print_vma_name(m, vma); + seq_putc(m, '\n'); + } + seq_printf(m, "Size: %8lu kB\n" "Rss: %8lu kB\n" |