Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:[EOL][EOL]ceph: fix multifs mds auth caps issue[EOL][EOL]The mds auth caps check should also validate the[EOL]fsname along with the associated caps. Not doing[EOL]so would result in applying the mds auth caps of[EOL]one fs on to the other fs in a multifs ceph cluster.[EOL]The bug causes multiple issues w.r.t user[EOL]authentication, following is one such example.[EOL][EOL]Steps to Reproduce (on vstart cluster):[EOL]1. Create two file systems in a cluster, say 'fsname1' and 'fsname2'[EOL]2. Authorize read only permission to the user 'client.usr' on fs 'fsname1'[EOL]    $ceph fs authorize fsname1 client.usr / r[EOL]3. Authorize read and write permission to the same user 'client.usr' on fs 'fsname2'[EOL]    $ceph fs authorize fsname2 client.usr / rw[EOL]4. Update the keyring[EOL]    $ceph auth get client.usr >> ./keyring[EOL][EOL]With above permssions for the user 'client.usr', following is the[EOL]expectation.[EOL]  a. The 'client.usr' should be able to only read the contents[EOL]     and not allowed to create or delete files on file system 'fsname1'.[EOL]  b. The 'client.usr' should be able to read/write on file system 'fsname2'.[EOL][EOL]But, with this bug, the 'client.usr' is allowed to read/write on file[EOL]system 'fsname1'. See below.[EOL][EOL]5. Mount the file system 'fsname1' with the user 'client.usr'[EOL]     $sudo bin/mount.ceph usr@.fsname1=/ /kmnt_fsname1_usr/[EOL]6. Try creating a file on file system 'fsname1' with user 'client.usr'. This[EOL]   should fail but passes with this bug.[EOL]     $touch /kmnt_fsname1_usr/file1[EOL]7. Mount the file system 'fsname1' with the user 'client.admin' and create a[EOL]   file.[EOL]     $sudo bin/mount.ceph admin@.fsname1=/ /kmnt_fsname1_admin[EOL]     $echo "data" > /kmnt_fsname1_admin/admin_file1[EOL]8. Try removing an existing file on file system 'fsname1' with the user[EOL]   'client.usr'. This shoudn't succeed but succeeds with the bug.[EOL]     $rm -f /kmnt_fsname1_usr/admin_file1[EOL][EOL]For more information, please take a look at the corresponding mds/fuse patch[EOL]and tests added by looking into the tracker mentioned below.[EOL][EOL]v2: Fix a possible null dereference in doutc[EOL]v3: Don't store fsname from mdsmap, validate against[EOL]    ceph_mount_options's fsname and use it[EOL]v4: Code refactor, better warning message and[EOL]    fix possible compiler warning[EOL][EOL][ Slava.Dubeyko: "fsname check failed" -> "fsname mismatch" ]