diff options
Diffstat (limited to 'fs/proc/base.c')
| -rw-r--r-- | fs/proc/base.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index eeaad0f45b6e..041678cd118d 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -841,7 +841,7 @@ static ssize_t mem_rw(struct file *file, char __user *buf, flags = FOLL_FORCE | (write ? FOLL_WRITE : 0); while (count > 0) { - int this_len = min_t(int, count, PAGE_SIZE); + size_t this_len = min_t(size_t, count, PAGE_SIZE); if (write && copy_from_user(page, buf, this_len)) { copied = -EFAULT; @@ -1041,7 +1041,6 @@ static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 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; @@ -1081,7 +1080,7 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) struct task_struct *p = find_lock_task_mm(task); if (p) { - if (atomic_read(&p->mm->mm_users) > 1) { + if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) { mm = p->mm; mmgrab(mm); } @@ -2529,6 +2528,13 @@ out: } #ifdef CONFIG_SECURITY +static int proc_pid_attr_open(struct inode *inode, struct file *file) +{ + file->private_data = NULL; + __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); + return 0; +} + static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, size_t count, loff_t *ppos) { @@ -2558,6 +2564,10 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, ssize_t length; struct task_struct *task = get_proc_task(inode); + /* A task may only write when it was the opener. */ + if (file->private_data != current->mm) + return -EPERM; + length = -ESRCH; if (!task) goto out_no_task; @@ -2598,9 +2608,11 @@ out_no_task: } static const struct file_operations proc_pid_attr_operations = { + .open = proc_pid_attr_open, .read = proc_pid_attr_read, .write = proc_pid_attr_write, .llseek = generic_file_llseek, + .release = mem_release, }; static const struct pid_entry attr_dir_stuff[] = { |