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-rw-r--r--fs/proc/base.c75
-rw-r--r--fs/proc/internal.h1
-rw-r--r--fs/proc/task_mmu.c34
-rw-r--r--fs/proc/task_nommu.c34
4 files changed, 75 insertions, 69 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c
index c5e412a00b1..b48ddb11994 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1181,6 +1181,81 @@ static const struct file_operations proc_pid_sched_operations = {
#endif
+/*
+ * We added or removed a vma mapping the executable. The vmas are only mapped
+ * during exec and are not mapped with the mmap system call.
+ * Callers must hold down_write() on the mm's mmap_sem for these
+ */
+void added_exe_file_vma(struct mm_struct *mm)
+{
+ mm->num_exe_file_vmas++;
+}
+
+void removed_exe_file_vma(struct mm_struct *mm)
+{
+ mm->num_exe_file_vmas--;
+ if ((mm->num_exe_file_vmas == 0) && mm->exe_file){
+ fput(mm->exe_file);
+ mm->exe_file = NULL;
+ }
+
+}
+
+void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
+{
+ if (new_exe_file)
+ get_file(new_exe_file);
+ if (mm->exe_file)
+ fput(mm->exe_file);
+ mm->exe_file = new_exe_file;
+ mm->num_exe_file_vmas = 0;
+}
+
+struct file *get_mm_exe_file(struct mm_struct *mm)
+{
+ struct file *exe_file;
+
+ /* We need mmap_sem to protect against races with removal of
+ * VM_EXECUTABLE vmas */
+ down_read(&mm->mmap_sem);
+ exe_file = mm->exe_file;
+ if (exe_file)
+ get_file(exe_file);
+ up_read(&mm->mmap_sem);
+ return exe_file;
+}
+
+void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm)
+{
+ /* It's safe to write the exe_file pointer without exe_file_lock because
+ * this is called during fork when the task is not yet in /proc */
+ newmm->exe_file = get_mm_exe_file(oldmm);
+}
+
+static int proc_exe_link(struct inode *inode, struct path *exe_path)
+{
+ struct task_struct *task;
+ struct mm_struct *mm;
+ struct file *exe_file;
+
+ task = get_proc_task(inode);
+ if (!task)
+ return -ENOENT;
+ mm = get_task_mm(task);
+ put_task_struct(task);
+ if (!mm)
+ return -ENOENT;
+ exe_file = get_mm_exe_file(mm);
+ mmput(mm);
+ if (exe_file) {
+ *exe_path = exe_file->f_path;
+ path_get(&exe_file->f_path);
+ fput(exe_file);
+ return 0;
+ } else
+ return -ENOENT;
+}
+
static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct inode *inode = dentry->d_inode;
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index bc72f5c8c47..45abb980398 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -48,7 +48,6 @@ extern int maps_protect;
extern void create_seq_entry(char *name, mode_t mode,
const struct file_operations *f);
-extern int proc_exe_link(struct inode *, struct path *);
extern int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task);
extern int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 7415eeb7cc3..e2b8e769f51 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -75,40 +75,6 @@ int task_statm(struct mm_struct *mm, int *shared, int *text,
return mm->total_vm;
}
-int proc_exe_link(struct inode *inode, struct path *path)
-{
- struct vm_area_struct * vma;
- int result = -ENOENT;
- struct task_struct *task = get_proc_task(inode);
- struct mm_struct * mm = NULL;
-
- if (task) {
- mm = get_task_mm(task);
- put_task_struct(task);
- }
- if (!mm)
- goto out;
- down_read(&mm->mmap_sem);
-
- vma = mm->mmap;
- while (vma) {
- if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file)
- break;
- vma = vma->vm_next;
- }
-
- if (vma) {
- *path = vma->vm_file->f_path;
- path_get(&vma->vm_file->f_path);
- result = 0;
- }
-
- up_read(&mm->mmap_sem);
- mmput(mm);
-out:
- return result;
-}
-
static void pad_len_spaces(struct seq_file *m, int len)
{
len = 25 + sizeof(void*) * 6 - len;
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 8011528518b..4b733f10845 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -103,40 +103,6 @@ int task_statm(struct mm_struct *mm, int *shared, int *text,
return size;
}
-int proc_exe_link(struct inode *inode, struct path *path)
-{
- struct vm_list_struct *vml;
- struct vm_area_struct *vma;
- struct task_struct *task = get_proc_task(inode);
- struct mm_struct *mm = get_task_mm(task);
- int result = -ENOENT;
-
- if (!mm)
- goto out;
- down_read(&mm->mmap_sem);
-
- vml = mm->context.vmlist;
- vma = NULL;
- while (vml) {
- if ((vml->vma->vm_flags & VM_EXECUTABLE) && vml->vma->vm_file) {
- vma = vml->vma;
- break;
- }
- vml = vml->next;
- }
-
- if (vma) {
- *path = vma->vm_file->f_path;
- path_get(&vma->vm_file->f_path);
- result = 0;
- }
-
- up_read(&mm->mmap_sem);
- mmput(mm);
-out:
- return result;
-}
-
/*
* display mapping lines for a particular process's /proc/pid/maps
*/