Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm...

[firefly-linux-kernel-4.4.55.git] / fs / proc / base.c

diff --git a/fs/proc/base.c b/fs/proc/base.c
index c47904994b78248fc1984914eab3b3c382952139..d2d3108a611c8cf96b6d1aa275270a3929556ccf 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1800,10 +1800,15 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
        if (task) {
                files = get_files_struct(task);
                if (files) {
+                       struct file *file;
                        rcu_read_lock();
-                       if (fcheck_files(files, fd)) {
+                       file = fcheck_files(files, fd);
+                       if (file) {
+                               unsigned i_mode, f_mode = file->f_mode;
+
                                rcu_read_unlock();
                                put_files_struct(files);
+
                                if (task_dumpable(task)) {
                                        rcu_read_lock();
                                        cred = __task_cred(task);
@@ -1814,7 +1819,14 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
                                        inode->i_uid = GLOBAL_ROOT_UID;
                                        inode->i_gid = GLOBAL_ROOT_GID;
                                }
-                               inode->i_mode &= ~(S_ISUID | S_ISGID);
+
+                               i_mode = S_IFLNK;
+                               if (f_mode & FMODE_READ)
+                                       i_mode |= S_IRUSR | S_IXUSR;
+                               if (f_mode & FMODE_WRITE)
+                                       i_mode |= S_IWUSR | S_IXUSR;
+                               inode->i_mode = i_mode;
+
                                security_task_to_inode(task, inode);
                                put_task_struct(task);
                                return 1;
@@ -1838,8 +1850,6 @@ static struct dentry *proc_fd_instantiate(struct inode *dir,
        struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
        unsigned fd = *(const unsigned *)ptr;
-       struct file *file;
-       struct files_struct *files;
        struct inode *inode;
        struct proc_inode *ei;
        struct dentry *error = ERR_PTR(-ENOENT);
@@ -1849,25 +1859,6 @@ static struct dentry *proc_fd_instantiate(struct inode *dir,
                goto out;
        ei = PROC_I(inode);
        ei->fd = fd;
-       files = get_files_struct(task);
-       if (!files)
-               goto out_iput;
-       inode->i_mode = S_IFLNK;
-
-       /*
-        * We are not taking a ref to the file structure, so we must
-        * hold ->file_lock.
-        */
-       spin_lock(&files->file_lock);
-       file = fcheck_files(files, fd);
-       if (!file)
-               goto out_unlock;
-       if (file->f_mode & FMODE_READ)
-               inode->i_mode |= S_IRUSR | S_IXUSR;
-       if (file->f_mode & FMODE_WRITE)
-               inode->i_mode |= S_IWUSR | S_IXUSR;
-       spin_unlock(&files->file_lock);
-       put_files_struct(files);
 
        inode->i_op = &proc_pid_link_inode_operations;
        inode->i_size = 64;
@@ -1880,12 +1871,6 @@ static struct dentry *proc_fd_instantiate(struct inode *dir,
 
  out:
        return error;
-out_unlock:
-       spin_unlock(&files->file_lock);
-       put_files_struct(files);
-out_iput:
-       iput(inode);
-       goto out;
 }
 
 static struct dentry *proc_lookupfd_common(struct inode *dir,
@@ -2178,16 +2163,16 @@ static struct dentry *proc_map_files_lookup(struct inode *dir,
                goto out;
 
        result = ERR_PTR(-EACCES);
-       if (lock_trace(task))
+       if (!ptrace_may_access(task, PTRACE_MODE_READ))
                goto out_put_task;
 
        result = ERR_PTR(-ENOENT);
        if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
-               goto out_unlock;
+               goto out_put_task;
 
        mm = get_task_mm(task);
        if (!mm)
-               goto out_unlock;
+               goto out_put_task;
 
        down_read(&mm->mmap_sem);
        vma = find_exact_vma(mm, vm_start, vm_end);
@@ -2199,8 +2184,6 @@ static struct dentry *proc_map_files_lookup(struct inode *dir,
 out_no_vma:
        up_read(&mm->mmap_sem);
        mmput(mm);
-out_unlock:
-       unlock_trace(task);
 out_put_task:
        put_task_struct(task);
 out:
@@ -2234,7 +2217,7 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
                goto out;
 
        ret = -EACCES;
-       if (lock_trace(task))
+       if (!ptrace_may_access(task, PTRACE_MODE_READ))
                goto out_put_task;
 
        ret = 0;
@@ -2242,12 +2225,12 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
        case 0:
                ino = inode->i_ino;
                if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
-                       goto out_unlock;
+                       goto out_put_task;
                filp->f_pos++;
        case 1:
                ino = parent_ino(dentry);
                if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
-                       goto out_unlock;
+                       goto out_put_task;
                filp->f_pos++;
        default:
        {
@@ -2258,7 +2241,7 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
 
                mm = get_task_mm(task);
                if (!mm)
-                       goto out_unlock;
+                       goto out_put_task;
                down_read(&mm->mmap_sem);
 
                nr_files = 0;
@@ -2288,7 +2271,7 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
                                        flex_array_free(fa);
                                up_read(&mm->mmap_sem);
                                mmput(mm);
-                               goto out_unlock;
+                               goto out_put_task;
                        }
                        for (i = 0, vma = mm->mmap, pos = 2; vma;
                                        vma = vma->vm_next) {
@@ -2333,8 +2316,6 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
        }
        }
 
-out_unlock:
-       unlock_trace(task);
 out_put_task:
        put_task_struct(task);
 out: