[LU-4704] Permission checking is missing when setfacl

• Type: Bug
• Resolution: Duplicate
• Priority: Blocker
• Fix Version/s: Lustre 2.6.0, Lustre 2.5.1, Lustre 2.4.3
• Affects Version/s: Lustre 2.6.0
• Labels: patch
• Severity: 3
• Assignee: Emoly Liu
• Reporter: Li Xi (Inactive)

Description

Setxattr does not check the permission when setting ACL xattrs. This
will cause security problem because any user can walk around permission
checking by changing ACL rules.

Following script will reproduce this problem.
#!/bin/bash
DIR=/mnt/lustre/dir

1. we can got this from Lustre/test
   RUNAS=./runas
   rmdir $DIR
   if [ -e $DIR ]; then
   echo "Please remove $DIR"
   exit 1
   fi

mkdir $DIR
if [ ! -d $DIR ]; then
echo "Faled to mkdir $DIR"
exit 1
fi

chmod 700 $DIR

$RUNAS -u test ls $DIR
if [ $? -eq 0 ]; then
echo "Permission error"
exit 1
fi

$RUNAS -u test setfacl -m u:test:rwx $DIR
if [ $? -ne 0 ]; then
echo "Probelm not reproduced because setfacl failed"
exit 1
fi

echo "Probelm reproduced!!"

$RUNAS -u test ls $DIR
if [ $? -ne 0 ]; then
echo "ACL does not work!"
exit 1
fi

echo "Security problem!!"

Issue Links

• duplicates: LU-4703 setxattr(2) will succeed by a non root user, against a file the user doesn't own.
• is related to: LU-4703 setxattr(2) will succeed by a non root user, against a file the user doesn't own.

Comments

[Nathaniel Clark]

backport sanity/103 (http://review.whamcloud.com/9541) tests to b2_5:
http://review.whamcloud.com/10512

[Bob Glossman (Inactive)]

backport to b2_4:
http://review.whamcloud.com/9559

[Emoly Liu]

The patch to enable acl/974.test and acl/2561.test is here: http://review.whamcloud.com/9541

[Bob Glossman (Inactive)]

backport to b2_5:
http://review.whamcloud.com/9514

[Andreas Dilger]

Emoly, I also see that acl/974.test and acl/2561.test are not included in the lustre/tests/Makefile.am nobase_noinst_DATA list, and those tests are being skipped. Could you please make a separate patch to add them to the list so they are in the RPM, and fix the test to fail if the test scripts are missing.