UBUNTU-CVE-2025-40362
In the Linux kernel, the following vulnerability has been resolved: ceph: fix multifs mds auth caps issue The mds auth caps check should also validate the fsname along with the associated caps. Not doing so would result in applying the mds auth caps of one fs on to the other fs in a multifs ceph cluster. The bug causes multiple issues w.r.t user authentication, following is one such example. Steps to Reproduce (on vstart cluster): 1. Create two file systems in a cluster, say 'fsname1' and 'fsname2' 2. Authorize read only permission to the user 'client.usr' on fs 'fsname1' $ceph fs authorize fsname1 client.usr / r 3. Authorize read and write permission to the same user 'client.usr' on fs 'fsname2' $ceph fs authorize fsname2 client.usr / rw 4. Update the keyring $ceph auth get client.usr >> ./keyring With above permssions for the user 'client.usr', following is the expectation. a. The 'client.usr' should be able to only read the contents and not allowed to create or delete files on file system 'fsname1'. b. The 'client.usr' should be able to read/write on file system 'fsname2'. But, with this bug, the 'client.usr' is allowed to read/write on file system 'fsname1'. See below. 5. Mount the file system 'fsname1' with the user 'client.usr' $sudo bin/mount.ceph [email protected]=/ /kmnt_fsname1_usr/ 6. Try creating a file on file system 'fsname1' with user 'client.usr'. This should fail but passes with this bug. $touch /kmnt_fsname1_usr/file1 7. Mount the file system 'fsname1' with the user 'client.admin' and create a file. $sudo bin/mount.ceph [email protected]=/ /kmnt_fsname1_admin $echo "data" > /kmnt_fsname1_admin/admin_file1 8. Try removing an existing file on file system 'fsname1' with the user 'client.usr'. This shoudn't succeed but succeeds with the bug. $rm -f /kmnt_fsname1_usr/admin_file1 For more information, please take a look at the corresponding mds/fuse patch and tests added by looking into the tracker mentioned below. v2: Fix a possible null dereference in doutc v3: Don't store fsname from mdsmap, validate against ceph_mount_options's fsname and use it v4: Code refactor, better warning message and fix possible compiler warning [ Slava.Dubeyko: "fsname check failed" -> "fsname mismatch" ]
02 / AFFECTED SOFTWARE
Affected packages
96 explicit affected versions
43 explicit affected versions
43 explicit affected versions
11 explicit affected versions
53 explicit affected versions
116 explicit affected versions
89 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
19 explicit affected versions
10 explicit affected versions
6 explicit affected versions
100 explicit affected versions
61 explicit affected versions
24 explicit affected versions
85 explicit affected versions
84 explicit affected versions
91 explicit affected versions
86 explicit affected versions
76 explicit affected versions
10 explicit affected versions
39 explicit affected versions
26 explicit affected versions
90 explicit affected versions
191 explicit affected versions
7 explicit affected versions
84 explicit affected versions
42 explicit affected versions
13 explicit affected versions
85 explicit affected versions
46 explicit affected versions
1 explicit affected versions
35 explicit affected versions
51 explicit affected versions
50 explicit affected versions
18 explicit affected versions
42 explicit affected versions
118 explicit affected versions
64 explicit affected versions
48 explicit affected versions
120 explicit affected versions
13 explicit affected versions
4 explicit affected versions
121 explicit affected versions
23 explicit affected versions
55 explicit affected versions
124 explicit affected versions
1 explicit affected versions
1 explicit affected versions
21 explicit affected versions
9 explicit affected versions
16 explicit affected versions
10 explicit affected versions
12 explicit affected versions
76 explicit affected versions
51 explicit affected versions
8 explicit affected versions
7 explicit affected versions
12 explicit affected versions
11 explicit affected versions
111 explicit affected versions
7 explicit affected versions
12 explicit affected versions
14 explicit affected versions
10 explicit affected versions
1 explicit affected versions
7 explicit affected versions
19 explicit affected versions
104 explicit affected versions
12 explicit affected versions
1 explicit affected versions
105 explicit affected versions
12 explicit affected versions
44 explicit affected versions
120 explicit affected versions
45 explicit affected versions
16 explicit affected versions
9 explicit affected versions
29 explicit affected versions
37 explicit affected versions
10 explicit affected versions
37 explicit affected versions
10 explicit affected versions
1 explicit affected versions
13 explicit affected versions
42 explicit affected versions
3 explicit affected versions
10 explicit affected versions
11 explicit affected versions
68 explicit affected versions
1 explicit affected versions
26 explicit affected versions
12 explicit affected versions
13 explicit affected versions
144 explicit affected versions
37 explicit affected versions
1 explicit affected versions
29 explicit affected versions
111 explicit affected versions
13 explicit affected versions
12 explicit affected versions
100 explicit affected versions
92 explicit affected versions
55 explicit affected versions
33 explicit affected versions
23 explicit affected versions
60 explicit affected versions
10 explicit affected versions
23 explicit affected versions
188 explicit affected versions
22 explicit affected versions
11 explicit affected versions
5 explicit affected versions
12 explicit affected versions
1 explicit affected versions
7 explicit affected versions
12 explicit affected versions
8 explicit affected versions
138 explicit affected versions
2 explicit affected versions
5 explicit affected versions
77 explicit affected versions
132 explicit affected versions
93 explicit affected versions
165 explicit affected versions
154 explicit affected versions
10 explicit affected versions
26 explicit affected versions
42 explicit affected versions
1 explicit affected versions
69 explicit affected versions
37 explicit affected versions
48 explicit affected versions
11 explicit affected versions
1 explicit affected versions
13 explicit affected versions
48 explicit affected versions
139 explicit affected versions
78 explicit affected versions
16 explicit affected versions
91 explicit affected versions
53 explicit affected versions
116 explicit affected versions
3 explicit affected versions
132 explicit affected versions
93 explicit affected versions
1 explicit affected versions
7 explicit affected versions
2 explicit affected versions
7 explicit affected versions
51 explicit affected versions
8 explicit affected versions
92 explicit affected versions
18 explicit affected versions
43 explicit affected versions
12 explicit affected versions
71 explicit affected versions
80 explicit affected versions
1 explicit affected versions
27 explicit affected versions
66 explicit affected versions
121 explicit affected versions
1 explicit affected versions
1 explicit affected versions
98 explicit affected versions
45 explicit affected versions
8 explicit affected versions
55 explicit affected versions
5 explicit affected versions
8 explicit affected versions
1 explicit affected versions
10 explicit affected versions
7 explicit affected versions
49 explicit affected versions
13 explicit affected versions
110 explicit affected versions
13 explicit affected versions
72 explicit affected versions
7 explicit affected versions
140 explicit affected versions
8 explicit affected versions
94 explicit affected versions
10 explicit affected versions
12 explicit affected versions
9 explicit affected versions
39 explicit affected versions
108 explicit affected versions
80 explicit affected versions
56 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
45 explicit affected versions
37 explicit affected versions
53 explicit affected versions
14 explicit affected versions
38 explicit affected versions
167 explicit affected versions
9 explicit affected versions
9 explicit affected versions
11 explicit affected versions
42 explicit affected versions
21 explicit affected versions
6 explicit affected versions
92 explicit affected versions
8 explicit affected versions
7 explicit affected versions
97 explicit affected versions
121 explicit affected versions
4 explicit affected versions
81 explicit affected versions
1 explicit affected versions
1 explicit affected versions
1 explicit affected versions
91 explicit affected versions
80 explicit affected versions
79 explicit affected versions
13 explicit affected versions
43 explicit affected versions
77 explicit affected versions
6 explicit affected versions
119 explicit affected versions
5 explicit affected versions
10 explicit affected versions
8 explicit affected versions
48 explicit affected versions
88 explicit affected versions
14 explicit affected versions
4 explicit affected versions
78 explicit affected versions
6 explicit affected versions
11 explicit affected versions
1 explicit affected versions
69 explicit affected versions
123 explicit affected versions
22 explicit affected versions
41 explicit affected versions
80 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: ceph: fix multifs mds auth caps issue The mds auth caps check should also validate the fsname along with the associated caps. Not doing so would result in applying the mds auth caps of one fs on to the other fs in a multifs ceph cluster. The bug causes multiple issues w.r.t user authentication, following is one such example. Steps to Reproduce (on vstart cluster): 1. Create two file systems in a cluster, say 'fsname1' and 'fsname2' 2. Authorize read only permission to the user 'client.usr' on fs 'fsname1' $ceph fs authorize fsname1 client.usr / r 3. Authorize read and write permission to the same user 'client.usr' on fs 'fsname2' $ceph fs authorize fsname2 client.usr / rw 4. Update the keyring $ceph auth get client.usr >> ./keyring With above permssions for the user 'client.usr', following is the expectation. a. The 'client.usr' should be able to only read the contents and not allowed to create or delete files on file system 'fsname1'. b. The 'client.usr' should be able to read/write on file system 'fsname2'. But, with this bug, the 'client.usr' is allowed to read/write on file system 'fsname1'. See below. 5. Mount the file system 'fsname1' with the user 'client.usr' $sudo bin/mount.ceph [email protected]=/ /kmnt_fsname1_usr/ 6. Try creating a file on file system 'fsname1' with user 'client.usr'. This should fail but passes with this bug. $touch /kmnt_fsname1_usr/file1 7. Mount the file system 'fsname1' with the user 'client.admin' and create a file. $sudo bin/mount.ceph [email protected]=/ /kmnt_fsname1_admin $echo "data" > /kmnt_fsname1_admin/admin_file1 8. Try removing an existing file on file system 'fsname1' with the user 'client.usr'. This shoudn't succeed but succeeds with the bug. $rm -f /kmnt_fsname1_usr/admin_file1 For more information, please take a look at the corresponding mds/fuse patch and tests added by looking into the tracker mentioned below. v2: Fix a possible null dereference in doutc v3: Don't store fsname from mdsmap, validate against ceph_mount_options's fsname and use it v4: Code refactor, better warning message and fix possible compiler warning [ Slava.Dubeyko: "fsname check failed" -> "fsname mismatch" ]
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/22c73d52a6d05c5a2053385c0d6cd9984732799d
- https://git.kernel.org/stable/c/07640d34a781bb2e39020a39137073c03c4aa932
- https://git.kernel.org/stable/c/22c73d52a6d05c5a2053385c0d6cd9984732799d
- https://git.kernel.org/stable/c/ca3da8b27ab9a0923ad477447cfb8fc7f4b4c523
- https://ubuntu.com/security/CVE-2025-40362
- https://ubuntu.com/security/notices/USN-8029-1
- https://ubuntu.com/security/notices/USN-8029-2
- https://ubuntu.com/security/notices/USN-8029-3
- https://ubuntu.com/security/notices/USN-8030-1
- https://ubuntu.com/security/notices/USN-8048-1
- https://www.cve.org/CVERecord?id=CVE-2025-40362