From: Tao Ma Date: Fri, 19 Mar 2010 07:04:23 +0000 (+0800) Subject: ocfs2: Fix the update of name_offset when removing xattrs X-Git-Tag: v2.6.34-rc3~5^2~5 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dfe4d3d6a6f707fff1dbfd4b8fce65e64a91b809;p=pandora-kernel.git ocfs2: Fix the update of name_offset when removing xattrs When replacing a xattr's value, in some case we wipe its name/value first and then re-add it. The wipe is done by ocfs2_xa_block_wipe_namevalue() when the xattr is in the inode or block. We currently adjust name_offset for all the entries which have (offset < name_offset). This does not adjust the entrie we're replacing. Since we are replacing the entry, we don't adjust the total entry count. When we calculate a new namevalue location, we trust the entries now-wrong offset in ocfs2_xa_get_free_start(). The solution is to also adjust the name_offset for the replaced entry, allowing ocfs2_xa_get_free_start() to calculate the new namevalue location correctly. The following script can trigger a kernel panic easily. echo 'y'|mkfs.ocfs2 --fs-features=local,xattr -b 4K $DEVICE mount -t ocfs2 $DEVICE $MNT_DIR FILE=$MNT_DIR/$RANDOM for((i=0;i<76;i++)) do string_76="a$string_76" done string_78="aa$string_76" string_82="aaaa$string_78" touch $FILE setfattr -n 'user.test1234567890' -v $string_76 $FILE setfattr -n 'user.test1234567890' -v $string_78 $FILE setfattr -n 'user.test1234567890' -v $string_82 $FILE Signed-off-by: Tao Ma Signed-off-by: Joel Becker --- Reading git-diff-tree failed