xfs: don't allow negative error tags
[cascardo/linux.git] / fs / exec.c
index a98b21d..887c1c9 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -243,10 +243,6 @@ static void put_arg_page(struct page *page)
        put_page(page);
 }
 
-static void free_arg_page(struct linux_binprm *bprm, int i)
-{
-}
-
 static void free_arg_pages(struct linux_binprm *bprm)
 {
 }
@@ -267,7 +263,10 @@ static int __bprm_mm_init(struct linux_binprm *bprm)
        if (!vma)
                return -ENOMEM;
 
-       down_write(&mm->mmap_sem);
+       if (down_write_killable(&mm->mmap_sem)) {
+               err = -EINTR;
+               goto err_free;
+       }
        vma->vm_mm = mm;
 
        /*
@@ -294,6 +293,7 @@ static int __bprm_mm_init(struct linux_binprm *bprm)
        return 0;
 err:
        up_write(&mm->mmap_sem);
+err_free:
        bprm->vma = NULL;
        kmem_cache_free(vm_area_cachep, vma);
        return err;
@@ -700,7 +700,9 @@ int setup_arg_pages(struct linux_binprm *bprm,
                bprm->loader -= stack_shift;
        bprm->exec -= stack_shift;
 
-       down_write(&mm->mmap_sem);
+       if (down_write_killable(&mm->mmap_sem))
+               return -EINTR;
+
        vm_flags = VM_STACK_FLAGS;
 
        /*
@@ -850,15 +852,25 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
        if (ret)
                return ret;
 
+       ret = deny_write_access(file);
+       if (ret)
+               return ret;
+
        i_size = i_size_read(file_inode(file));
-       if (max_size > 0 && i_size > max_size)
-               return -EFBIG;
-       if (i_size <= 0)
-               return -EINVAL;
+       if (max_size > 0 && i_size > max_size) {
+               ret = -EFBIG;
+               goto out;
+       }
+       if (i_size <= 0) {
+               ret = -EINVAL;
+               goto out;
+       }
 
        *buf = vmalloc(i_size);
-       if (!*buf)
-               return -ENOMEM;
+       if (!*buf) {
+               ret = -ENOMEM;
+               goto out;
+       }
 
        pos = 0;
        while (pos < i_size) {
@@ -876,18 +888,21 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size,
 
        if (pos != i_size) {
                ret = -EIO;
-               goto out;
+               goto out_free;
        }
 
        ret = security_kernel_post_read_file(file, *buf, i_size, id);
        if (!ret)
                *size = pos;
 
-out:
+out_free:
        if (ret < 0) {
                vfree(*buf);
                *buf = NULL;
        }
+
+out:
+       allow_write_access(file);
        return ret;
 }
 EXPORT_SYMBOL_GPL(kernel_read_file);
@@ -1486,9 +1501,6 @@ int remove_arg_zero(struct linux_binprm *bprm)
 
                kunmap_atomic(kaddr);
                put_arg_page(page);
-
-               if (offset == PAGE_SIZE)
-                       free_arg_page(bprm, (bprm->p >> PAGE_SHIFT) - 1);
        } while (offset == PAGE_SIZE);
 
        bprm->p++;