Description: MDS may lose file striping (and hence file data) in some cases

  Details    : If there are additional extended attributes stored on the MDS,
             in particular ACLs, SELinux, or user attributes (if user_xattr
             is specified for the client mount options) then there is a risk
             of attribute loss.  Additionally, the Lustre file striping
             needs to be larger than default (e.g. striped over all OSTs),
             and an additional attribute must be stored initially in the
             inode and then increase in size enough to be moved to the
             external attribute block (e.g. ACL growing in size) for file
             data to be lost.
i=adilger
i=kalpak.shah (test by adilger)
b=15777

diff --git a/lustre/ChangeLog b/lustre/ChangeLog
index 8132526..36265d4 100644 (file)
--- a/lustre/ChangeLog
+++ b/lustre/ChangeLog
@@ -996,6 +996,20 @@ Severity   : normal
 Bugzilla   : 15212
 Description: Reinitialize optind to 0 so that interactive lfs works in all cases
 
+Severity   : critical
+Frequency  : very rare, if additional xattrs are used on kernels >= 2.6.12
+Bugzilla   : 15777
+Description: MDS may lose file striping (and hence file data) in some cases
+Details    : If there are additional extended attributes stored on the MDS,
+            in particular ACLs, SELinux, or user attributes (if user_xattr
+            is specified for the client mount options) then there is a risk
+            of attribute loss.  Additionally, the Lustre file striping
+            needs to be larger than default (e.g. striped over all OSTs),
+            and an additional attribute must be stored initially in the
+            inode and then increase in size enough to be moved to the
+            external attribute block (e.g. ACL growing in size) for file
+            data to be lost.
+
 --------------------------------------------------------------------------------
 
 2007-08-10         Cluster File Systems, Inc. <info@clusterfs.com>

diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index 691e47f..b309951 100644 (file)
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -3874,6 +3874,50 @@ test_102g() {
 }
 run_test 102g "star copy files, keep osts ==========="
 
+test_102h() { # bug 15777
+       [ -z $(lctl get_param -n mdc.*.connect_flags | grep xattr) ] &&
+               skip "must have user_xattr" && return
+       [ -z "$(which setfattr 2>/dev/null)" ] &&
+               skip "could not find setfattr" && return
+
+       XBIG=trusted.big
+       XSIZE=1024
+       touch $DIR/$tfile
+       VALUE=datadatadatadatadatadatadatadata
+       while [ $(echo $VALUE | wc -c) -lt $XSIZE ]; do
+               VALUE="$VALUE$VALUE"
+       done
+       log "save $XBIG on $DIR/$tfile"
+        setfattr -n $XBIG -v "$VALUE" $DIR/$tfile ||
+               error "saving $XBIG on $DIR/$tfile failed"
+        ORIG=$(getfattr -n $XBIG $DIR/$tfile 2> /dev/null | grep $XBIG)
+       OSIZE=$(echo $ORIG | wc -c)
+       [ $OSIZE -lt $XSIZE ] && error "set $XBIG too small ($OSIZE < $XSIZE)"
+
+       XSML=trusted.sml
+       log "save $XSML on $DIR/$tfile"
+        setfattr -n $XSML -v val $DIR/$tfile ||
+               error "saving $XSML on $DIR/$tfile failed"
+        NEW=$(getfattr -n $XBIG $DIR/$tfile 2> /dev/null | grep $XBIG)
+       if [ "$NEW" != "$ORIG" ]; then
+               log "orig: $ORIG"
+               log "new: $NEW"
+               error "$XBIG different after saving $XSML"
+       fi
+
+       log "grow $XSML on $DIR/$tfile"
+        setfattr -n $XSML -v "$VALUE" $DIR/$tfile ||
+               error "growing $XSML on $DIR/$tfile failed"
+        NEW=$(getfattr -n $XBIG $DIR/$tfile 2> /dev/null | grep $XBIG)
+       if [ "$NEW" != "$ORIG" ]; then
+               log "orig: $ORIG"
+               log "new: $NEW"
+               error "$XBIG different after growing $XSML"
+       fi
+       log "$XBIG still valid after growing $XSML"
+}
+run_test 102h "grow xattr from inside inode to external block"
+
 run_acl_subtest()
 {
     $LUSTRE/tests/acl/run $LUSTRE/tests/acl/$1.test