Commit a41f2071 authored Jun 10, 2009 by Aneesh Kumar K.V Committed by Theodore Ts'o Jun 10, 2009

ext4: Avoid corrupting the uninitialized bit in the extent during truncate



The unitialized bit was not properly getting preserved in in an extent
which is partially truncated because the it was geting set to the
value of the first extent to be removed or truncated as part of the
truncate operation, and if there are multiple extents are getting
removed or modified as part of the truncate operation, it is only the
last extent which will might be partially truncated, and its
uninitalized bit is not necessarily the same as the first extent to be
truncated.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

parent 0eab9282

fs/ext4/extents.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -2083,12 +2083,16 @@ ext4_ext_rm_leaf(handle_t handle, struct inode inode,
		ex = EXT_LAST_EXTENT(eh);

		ex_ee_block = le32_to_cpu(ex->ee_block);
		if (ext4_ext_is_uninitialized(ex))
		uninitialized = 1;
		ex_ee_len = ext4_ext_get_actual_len(ex);

		while (ex >= EXT_FIRST_EXTENT(eh) &&
		ex_ee_block + ex_ee_len > start) {

		if (ext4_ext_is_uninitialized(ex))
		uninitialized = 1;
		else
		uninitialized = 0;

		ext_debug("remove ext %lu:%u\n", ex_ee_block, ex_ee_len);
		path[depth].p_ext = ex;

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