useradd.bbclass: retry useradd/groupadd commands to avoid lock race issues

A race condition can occur when adding users and groups to the
passwd and group files, causing errors like the following:

 ERROR: Function 'useradd_sysroot' failed
 Tried to access "/etc/group" but this was locked.

This fix will cause the useradd code to retry the useradd and
groupadd commands up to 10 times (with a 1s sleep in between
attempts) before failing.

This fixes [YOCTO #1794]

(From OE-Core rev: 68c589f1b5ee36f0aff151b728447ffdae14622c)

Signed-off-by: Scott Garman <scott.a.garman@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 34 insertions, 2 deletions

diff --git a/meta/classes/useradd.bbclass b/meta/classes/useradd.bbclass
index 7981a68dff..0bbb371b2a 100644
--- a/meta/classes/useradd.bbclass
+++ b/meta/classes/useradd.bbclass
@@ -45,7 +45,23 @@ if test "x$GROUPADD_PARAM" != "x"; then
                 groupname=`echo "$opts" | awk '{ print $NF }'`
                 group_exists=`grep "^$groupname:" $SYSROOT/etc/group || true`
                 if test "x$group_exists" = "x"; then
-                        eval $PSEUDO groupadd  $OPT $opts
+                        count=1
+                        while true; do
+                                eval $PSEUDO groupadd $OPT $opts || true
+                                group_exists=`grep "^$groupname:" $SYSROOT/etc/group || true`
+                                if test "x$group_exists" = "x"; then
+                                        # File locking issues can require us to retry the command
+                                        echo "WARNING: groupadd command did not succeed. Retrying..."
+                                        sleep 1
+                                else
+                                        break
+                                fi
+                                count=`expr $count + 1`
+                                if test $count = 11; then
+                                        echo "ERROR: tried running groupadd command 10 times without success, giving up"
+                                        exit 1
+                                fi
+                        done            
                 else
                         echo "Note: group $groupname already exists, not re-creating it"
                 fi
@@ -70,7 +86,23 @@ if test "x$USERADD_PARAM" != "x"; then
                 username=`echo "$opts" | awk '{ print $NF }'`
                 user_exists=`grep "^$username:" $SYSROOT/etc/passwd || true`
                 if test "x$user_exists" = "x"; then
-                        eval $PSEUDO useradd $OPT $opts
+                        count=1
+                        while true; do
+                                eval $PSEUDO useradd $OPT $opts || true
+                                user_exists=`grep "^$username:" $SYSROOT/etc/passwd || true`
+                                if test "x$user_exists" = "x"; then
+                                        # File locking issues can require us to retry the command
+                                        echo "WARNING: useradd command did not succeed. Retrying..."
+                                        sleep 1
+                                else
+                                        break
+                                fi
+                                count=`expr $count + 1`
+                                if test $count = 11; then
+                                        echo "ERROR: tried running useradd command 10 times without success, giving up"
+                                        exit 1
+                                fi
+                        done
                 else
                         echo "Note: username $username already exists, not re-creating it"
                 fi