diff options
author | 2016-04-11 10:41:07 +0300 | |
---|---|---|
committer | 2016-04-13 08:17:18 +0300 | |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/fs/proc/base.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/fs/proc/base.c')
-rw-r--r-- | kernel/fs/proc/base.c | 379 |
1 files changed, 280 insertions, 99 deletions
diff --git a/kernel/fs/proc/base.c b/kernel/fs/proc/base.c index 093ca14f5..b7de324be 100644 --- a/kernel/fs/proc/base.c +++ b/kernel/fs/proc/base.c @@ -196,22 +196,214 @@ static int proc_root_link(struct dentry *dentry, struct path *path) return result; } -static int proc_pid_cmdline(struct seq_file *m, struct pid_namespace *ns, - struct pid *pid, struct task_struct *task) +static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, + size_t _count, loff_t *pos) { + struct task_struct *tsk; + struct mm_struct *mm; + char *page; + unsigned long count = _count; + unsigned long arg_start, arg_end, env_start, env_end; + unsigned long len1, len2, len; + unsigned long p; + char c; + ssize_t rv; + + BUG_ON(*pos < 0); + + tsk = get_proc_task(file_inode(file)); + if (!tsk) + return -ESRCH; + mm = get_task_mm(tsk); + put_task_struct(tsk); + if (!mm) + return 0; + /* Check if process spawned far enough to have cmdline. */ + if (!mm->env_end) { + rv = 0; + goto out_mmput; + } + + page = (char *)__get_free_page(GFP_TEMPORARY); + if (!page) { + rv = -ENOMEM; + goto out_mmput; + } + + down_read(&mm->mmap_sem); + arg_start = mm->arg_start; + arg_end = mm->arg_end; + env_start = mm->env_start; + env_end = mm->env_end; + up_read(&mm->mmap_sem); + + BUG_ON(arg_start > arg_end); + BUG_ON(env_start > env_end); + + len1 = arg_end - arg_start; + len2 = env_end - env_start; + + /* Empty ARGV. */ + if (len1 == 0) { + rv = 0; + goto out_free_page; + } /* - * Rely on struct seq_operations::show() being called once - * per internal buffer allocation. See single_open(), traverse(). + * Inherently racy -- command line shares address space + * with code and data. */ - BUG_ON(m->size < PAGE_SIZE); - m->count += get_cmdline(task, m->buf, PAGE_SIZE); - return 0; + rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0); + if (rv <= 0) + goto out_free_page; + + rv = 0; + + if (c == '\0') { + /* Command line (set of strings) occupies whole ARGV. */ + if (len1 <= *pos) + goto out_free_page; + + p = arg_start + *pos; + len = len1 - *pos; + while (count > 0 && len > 0) { + unsigned int _count; + int nr_read; + + _count = min3(count, len, PAGE_SIZE); + nr_read = access_remote_vm(mm, p, page, _count, 0); + if (nr_read < 0) + rv = nr_read; + if (nr_read <= 0) + goto out_free_page; + + if (copy_to_user(buf, page, nr_read)) { + rv = -EFAULT; + goto out_free_page; + } + + p += nr_read; + len -= nr_read; + buf += nr_read; + count -= nr_read; + rv += nr_read; + } + } else { + /* + * Command line (1 string) occupies ARGV and maybe + * extends into ENVP. + */ + if (len1 + len2 <= *pos) + goto skip_argv_envp; + if (len1 <= *pos) + goto skip_argv; + + p = arg_start + *pos; + len = len1 - *pos; + while (count > 0 && len > 0) { + unsigned int _count, l; + int nr_read; + bool final; + + _count = min3(count, len, PAGE_SIZE); + nr_read = access_remote_vm(mm, p, page, _count, 0); + if (nr_read < 0) + rv = nr_read; + if (nr_read <= 0) + goto out_free_page; + + /* + * Command line can be shorter than whole ARGV + * even if last "marker" byte says it is not. + */ + final = false; + l = strnlen(page, nr_read); + if (l < nr_read) { + nr_read = l; + final = true; + } + + if (copy_to_user(buf, page, nr_read)) { + rv = -EFAULT; + goto out_free_page; + } + + p += nr_read; + len -= nr_read; + buf += nr_read; + count -= nr_read; + rv += nr_read; + + if (final) + goto out_free_page; + } +skip_argv: + /* + * Command line (1 string) occupies ARGV and + * extends into ENVP. + */ + if (len1 <= *pos) { + p = env_start + *pos - len1; + len = len1 + len2 - *pos; + } else { + p = env_start; + len = len2; + } + while (count > 0 && len > 0) { + unsigned int _count, l; + int nr_read; + bool final; + + _count = min3(count, len, PAGE_SIZE); + nr_read = access_remote_vm(mm, p, page, _count, 0); + if (nr_read < 0) + rv = nr_read; + if (nr_read <= 0) + goto out_free_page; + + /* Find EOS. */ + final = false; + l = strnlen(page, nr_read); + if (l < nr_read) { + nr_read = l; + final = true; + } + + if (copy_to_user(buf, page, nr_read)) { + rv = -EFAULT; + goto out_free_page; + } + + p += nr_read; + len -= nr_read; + buf += nr_read; + count -= nr_read; + rv += nr_read; + + if (final) + goto out_free_page; + } +skip_argv_envp: + ; + } + +out_free_page: + free_page((unsigned long)page); +out_mmput: + mmput(mm); + if (rv > 0) + *pos += rv; + return rv; } +static const struct file_operations proc_pid_cmdline_ops = { + .read = proc_pid_cmdline_read, + .llseek = generic_file_llseek, +}; + static int proc_pid_auxv(struct seq_file *m, struct pid_namespace *ns, struct pid *pid, struct task_struct *task) { - struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ); + struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); if (mm && !IS_ERR(mm)) { unsigned int nwords = 0; do { @@ -238,13 +430,11 @@ static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, wchan = get_wchan(task); - if (lookup_symbol_name(wchan, symname) < 0) { - if (!ptrace_may_access(task, PTRACE_MODE_READ)) - return 0; - seq_printf(m, "%lu", wchan); - } else { + if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS) + && !lookup_symbol_name(wchan, symname)) seq_printf(m, "%s", symname); - } + else + seq_putc(m, '0'); return 0; } @@ -255,7 +445,7 @@ 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)) { + if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { mutex_unlock(&task->signal->cred_guard_mutex); return -EPERM; } @@ -304,14 +494,17 @@ static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, } #endif -#ifdef CONFIG_SCHEDSTATS +#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) { - seq_printf(m, "%llu %llu %lu\n", + 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); @@ -505,7 +698,7 @@ static int proc_fd_access_allowed(struct inode *inode) */ task = get_proc_task(inode); if (task) { - allowed = ptrace_may_access(task, PTRACE_MODE_READ); + allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); put_task_struct(task); } return allowed; @@ -540,7 +733,7 @@ static bool has_pid_permissions(struct pid_namespace *pid, return true; if (in_group_p(pid->pid_gid)) return true; - return ptrace_may_access(task, PTRACE_MODE_READ); + return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); } @@ -617,7 +810,7 @@ struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) struct mm_struct *mm = ERR_PTR(-ESRCH); if (task) { - mm = mm_access(task, mode); + mm = mm_access(task, mode | PTRACE_MODE_FSCREDS); put_task_struct(task); if (!IS_ERR_OR_NULL(mm)) { @@ -840,6 +1033,16 @@ static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, return simple_read_from_buffer(buf, count, ppos, buffer, len); } +/* + * /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) { @@ -1035,10 +1238,9 @@ 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); - char *page, *tmp; - ssize_t length; uid_t loginuid; kuid_t kloginuid; + int rv; rcu_read_lock(); if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { @@ -1047,46 +1249,28 @@ static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, } rcu_read_unlock(); - if (count >= PAGE_SIZE) - count = PAGE_SIZE - 1; - if (*ppos != 0) { /* No partial writes. */ return -EINVAL; } - page = (char*)__get_free_page(GFP_TEMPORARY); - if (!page) - return -ENOMEM; - length = -EFAULT; - if (copy_from_user(page, buf, count)) - goto out_free_page; - page[count] = '\0'; - loginuid = simple_strtoul(page, &tmp, 10); - if (tmp == page) { - length = -EINVAL; - goto out_free_page; - - } + 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)) { - length = -EINVAL; - goto out_free_page; - } + if (!uid_valid(kloginuid)) + return -EINVAL; } - length = audit_set_loginuid(kloginuid); - if (likely(length == 0)) - length = count; - -out_free_page: - free_page((unsigned long) page); - return length; + rv = audit_set_loginuid(kloginuid); + if (rv < 0) + return rv; + return count; } static const struct file_operations proc_loginuid_operations = { @@ -1140,8 +1324,9 @@ 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], *end; + char buffer[PROC_NUMBUF]; int make_it_fail; + int rv; if (!capable(CAP_SYS_RESOURCE)) return -EPERM; @@ -1150,9 +1335,9 @@ static ssize_t proc_fault_inject_write(struct file * file, count = sizeof(buffer) - 1; if (copy_from_user(buffer, buf, count)) return -EFAULT; - make_it_fail = simple_strtol(strstrip(buffer), &end, 0); - if (*end) - return -EINVAL; + rv = kstrtoint(strstrip(buffer), 0, &make_it_fail); + if (rv < 0) + return rv; if (make_it_fail < 0 || make_it_fail > 1) return -EINVAL; @@ -1380,7 +1565,7 @@ static int proc_exe_link(struct dentry *dentry, struct path *exe_path) return -ENOENT; } -static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) +static const char *proc_pid_follow_link(struct dentry *dentry, void **cookie) { struct inode *inode = d_inode(dentry); struct path path; @@ -1394,7 +1579,7 @@ static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) if (error) goto out; - nd_jump_link(nd, &path); + nd_jump_link(&path); return NULL; out: return ERR_PTR(error); @@ -1641,8 +1826,6 @@ end_instantiate: return dir_emit(ctx, name, len, 1, DT_UNKNOWN); } -#ifdef CONFIG_CHECKPOINT_RESTORE - /* * dname_to_vma_addr - maps a dentry name into two unsigned longs * which represent vma start and end addresses. @@ -1669,17 +1852,12 @@ static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) if (flags & LOOKUP_RCU) return -ECHILD; - if (!capable(CAP_SYS_ADMIN)) { - status = -EPERM; - goto out_notask; - } - inode = d_inode(dentry); task = get_proc_task(inode); if (!task) goto out_notask; - mm = mm_access(task, PTRACE_MODE_READ); + mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); if (IS_ERR_OR_NULL(mm)) goto out; @@ -1762,6 +1940,29 @@ struct map_files_info { unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */ }; +/* + * 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_follow_link(struct dentry *dentry, void **cookie) +{ + if (!capable(CAP_SYS_ADMIN)) + return ERR_PTR(-EPERM); + + return proc_pid_follow_link(dentry, NULL); +} + +/* + * Identical to proc_pid_link_inode_operations except for follow_link() + */ +static const struct inode_operations proc_map_files_link_inode_operations = { + .readlink = proc_pid_readlink, + .follow_link = proc_map_files_follow_link, + .setattr = proc_setattr, +}; + static int proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, struct task_struct *task, const void *ptr) @@ -1777,7 +1978,7 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, ei = PROC_I(inode); ei->op.proc_get_link = proc_map_files_get_link; - inode->i_op = &proc_pid_link_inode_operations; + inode->i_op = &proc_map_files_link_inode_operations; inode->i_size = 64; inode->i_mode = S_IFLNK; @@ -1801,17 +2002,13 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, int result; struct mm_struct *mm; - result = -EPERM; - if (!capable(CAP_SYS_ADMIN)) - goto out; - result = -ENOENT; task = get_proc_task(dir); if (!task) goto out; result = -EACCES; - if (!ptrace_may_access(task, PTRACE_MODE_READ)) + if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) goto out_put_task; result = -ENOENT; @@ -1858,17 +2055,13 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx) struct map_files_info *p; int ret; - ret = -EPERM; - if (!capable(CAP_SYS_ADMIN)) - goto out; - ret = -ENOENT; task = get_proc_task(file_inode(file)); if (!task) goto out; ret = -EACCES; - if (!ptrace_may_access(task, PTRACE_MODE_READ)) + if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) goto out_put_task; ret = 0; @@ -2050,7 +2243,6 @@ static const struct file_operations proc_timers_operations = { .llseek = seq_lseek, .release = seq_release_private, }; -#endif /* CONFIG_CHECKPOINT_RESTORE */ static int proc_pident_instantiate(struct inode *dir, struct dentry *dentry, struct task_struct *task, const void *ptr) @@ -2286,35 +2478,24 @@ static ssize_t proc_coredump_filter_write(struct file *file, { struct task_struct *task; struct mm_struct *mm; - char buffer[PROC_NUMBUF], *end; unsigned int val; int ret; int i; unsigned long mask; - ret = -EFAULT; - memset(buffer, 0, sizeof(buffer)); - if (count > sizeof(buffer) - 1) - count = sizeof(buffer) - 1; - if (copy_from_user(buffer, buf, count)) - goto out_no_task; - - ret = -EINVAL; - val = (unsigned int)simple_strtoul(buffer, &end, 0); - if (*end == '\n') - end++; - if (end - buffer == 0) - goto out_no_task; + 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; - ret = end - buffer; 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) @@ -2327,7 +2508,9 @@ static ssize_t proc_coredump_filter_write(struct file *file, out_no_mm: put_task_struct(task); out_no_task: - return ret; + if (ret < 0) + return ret; + return count; } static const struct file_operations proc_coredump_filter_operations = { @@ -2348,7 +2531,7 @@ static int do_io_accounting(struct task_struct *task, struct seq_file *m, int wh if (result) return result; - if (!ptrace_may_access(task, PTRACE_MODE_READ)) { + if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { result = -EACCES; goto out_unlock; } @@ -2549,9 +2732,7 @@ 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), -#ifdef CONFIG_CHECKPOINT_RESTORE DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), -#endif 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 @@ -2572,7 +2753,7 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_HAVE_ARCH_TRACEHOOK ONE("syscall", S_IRUSR, proc_pid_syscall), #endif - ONE("cmdline", S_IRUGO, proc_pid_cmdline), + 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), @@ -2600,7 +2781,7 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_STACKTRACE ONE("stack", S_IRUSR, proc_pid_stack), #endif -#ifdef CONFIG_SCHEDSTATS +#ifdef CONFIG_SCHED_INFO ONE("schedstat", S_IRUGO, proc_pid_schedstat), #endif #ifdef CONFIG_LATENCYTOP @@ -2918,11 +3099,11 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_HAVE_ARCH_TRACEHOOK ONE("syscall", S_IRUSR, proc_pid_syscall), #endif - ONE("cmdline", S_IRUGO, proc_pid_cmdline), + REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), ONE("stat", S_IRUGO, proc_tid_stat), ONE("statm", S_IRUGO, proc_pid_statm), REG("maps", S_IRUGO, proc_tid_maps_operations), -#ifdef CONFIG_CHECKPOINT_RESTORE +#ifdef CONFIG_PROC_CHILDREN REG("children", S_IRUGO, proc_tid_children_operations), #endif #ifdef CONFIG_NUMA @@ -2948,7 +3129,7 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_STACKTRACE ONE("stack", S_IRUSR, proc_pid_stack), #endif -#ifdef CONFIG_SCHEDSTATS +#ifdef CONFIG_SCHED_INFO ONE("schedstat", S_IRUGO, proc_pid_schedstat), #endif #ifdef CONFIG_LATENCYTOP |