ext4: enforce we are operating on a regular file in ext4_zero_range()

[mirror_ubuntu-bionic-kernel.git] / fs / ext4 / extents.c

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index c6f624582d37ed1d55fcbd2e8afbf1b04141e1e1..2f49b12a4c40f66b6ec2700a5655d16bc30fc5cf 100644 (file)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4741,6 +4741,9 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 
        trace_ext4_zero_range(inode, offset, len, mode);
 
+       if (!S_ISREG(inode->i_mode))
+               return -EINVAL;
+
        /*
         * Write out all dirty pages to avoid race conditions
         * Then release them.
@@ -5245,13 +5248,14 @@ ext4_ext_shift_path_extents(struct ext4_ext_path *path, ext4_lblk_t shift,
 
                        while (ex_start <= ex_last) {
                                le32_add_cpu(&ex_start->ee_block, -shift);
-                               if (ex_start >
-                                       EXT_FIRST_EXTENT(path[depth].p_hdr)) {
-                                       if (ext4_ext_try_to_merge_right(inode,
-                                               path, ex_start - 1))
-                                               ex_last--;
-                               }
-                               ex_start++;
+                               /* Try to merge to the left. */
+                               if ((ex_start >
+                                    EXT_FIRST_EXTENT(path[depth].p_hdr)) &&
+                                   ext4_ext_try_to_merge_right(inode,
+                                                       path, ex_start - 1))
+                                       ex_last--;
+                               else
+                                       ex_start++;
                        }
                        err = ext4_ext_dirty(handle, inode, path + depth);
                        if (err)
@@ -5465,6 +5469,7 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
                up_write(&EXT4_I(inode)->i_data_sem);
                goto out_stop;
        }
+       ext4_discard_preallocations(inode);
 
        ret = ext4_ext_shift_extents(inode, handle, punch_stop,
                                     punch_stop - punch_start);
@@ -5474,10 +5479,9 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len)
        }
 
        new_size = i_size_read(inode) - len;
-       truncate_setsize(inode, new_size);
+       i_size_write(inode, new_size);
        EXT4_I(inode)->i_disksize = new_size;
 
-       ext4_discard_preallocations(inode);
        up_write(&EXT4_I(inode)->i_data_sem);
        if (IS_SYNC(inode))
                ext4_handle_sync(handle);