From: Aneesh Kumar K.V Date: Wed, 10 Jun 2009 18:22:55 +0000 (-0400) Subject: ext4: Avoid corrupting the uninitialized bit in the extent during truncate Patch-mainline: 2.6.31-rc1 Git-commit: a41f20716975910d9beb90b7efc61107901492b8 References: bnc#514265 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 Signed-off-by: "Theodore Ts'o" Acked-by: Jeff Mahoney --- fs/ext4/extents.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -1877,12 +1877,16 @@ ext4_ext_rm_leaf(handle_t *handle, struc 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;