diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/binfmt_flat.c | 3 | ||||
| -rw-r--r-- | fs/exec.c | 2 | ||||
| -rw-r--r-- | fs/proc/base.c | 75 | ||||
| -rw-r--r-- | fs/proc/internal.h | 1 | ||||
| -rw-r--r-- | fs/proc/task_mmu.c | 34 | ||||
| -rw-r--r-- | fs/proc/task_nommu.c | 34 |
6 files changed, 79 insertions, 70 deletions
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index c12cc36..3b40d45 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -531,7 +531,8 @@ static int load_flat_file(struct linux_binprm * bprm, DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n"); down_write(¤t->mm->mmap_sem); - textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, MAP_PRIVATE, 0); + textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, + MAP_PRIVATE|MAP_EXECUTABLE, 0); up_write(¤t->mm->mmap_sem); if (!textpos || textpos >= (unsigned long) -4096) { if (!textpos) @@ -964,6 +964,8 @@ int flush_old_exec(struct linux_binprm * bprm) if (retval) goto out; + set_mm_exe_file(bprm->mm, bprm->file); + /* * Release all of the old mmap stuff */ diff --git a/fs/proc/base.c b/fs/proc/base.c index c5e412a..b48ddb1 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 bc72f5c..45abb98 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 7415eeb..e2b8e76 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 8011528..4b733f1 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 */ |