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UBUNTU-CVE-2025-68285 Critical

UBUNTU-CVE-2025-68285

In the Linux kernel, the following vulnerability has been resolved: libceph: fix potential use-after-free in have_mon_and_osd_map() The wait loop in __ceph_open_session() can race with the client receiving a new monmap or osdmap shortly after the initial map is received. Both ceph_monc_handle_map() and handle_one_map() install a new map immediately after freeing the old one kfree(monc->monmap); monc->monmap = monmap; ceph_osdmap_destroy(osdc->osdmap); osdc->osdmap = newmap; under client->monc.mutex and client->osdc.lock respectively, but because neither is taken in have_mon_and_osd_map() it's possible for client->monc.monmap->epoch and client->osdc.osdmap->epoch arms in client->monc.monmap && client->monc.monmap->epoch && client->osdc.osdmap && client->osdc.osdmap->epoch; condition to dereference an already freed map. This happens to be reproducible with generic/395 and generic/397 with KASAN enabled: BUG: KASAN: slab-use-after-free in have_mon_and_osd_map+0x56/0x70 Read of size 4 at addr ffff88811012d810 by task mount.ceph/13305 CPU: 2 UID: 0 PID: 13305 Comm: mount.ceph Not tainted 6.14.0-rc2-build2+ #1266 ... Call Trace: <TASK> have_mon_and_osd_map+0x56/0x70 ceph_open_session+0x182/0x290 ceph_get_tree+0x333/0x680 vfs_get_tree+0x49/0x180 do_new_mount+0x1a3/0x2d0 path_mount+0x6dd/0x730 do_mount+0x99/0xe0 __do_sys_mount+0x141/0x180 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> Allocated by task 13305: ceph_osdmap_alloc+0x16/0x130 ceph_osdc_init+0x27a/0x4c0 ceph_create_client+0x153/0x190 create_fs_client+0x50/0x2a0 ceph_get_tree+0xff/0x680 vfs_get_tree+0x49/0x180 do_new_mount+0x1a3/0x2d0 path_mount+0x6dd/0x730 do_mount+0x99/0xe0 __do_sys_mount+0x141/0x180 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 9475: kfree+0x212/0x290 handle_one_map+0x23c/0x3b0 ceph_osdc_handle_map+0x3c9/0x590 mon_dispatch+0x655/0x6f0 ceph_con_process_message+0xc3/0xe0 ceph_con_v1_try_read+0x614/0x760 ceph_con_workfn+0x2de/0x650 process_one_work+0x486/0x7c0 process_scheduled_works+0x73/0x90 worker_thread+0x1c8/0x2a0 kthread+0x2ec/0x300 ret_from_fork+0x24/0x40 ret_from_fork_asm+0x1a/0x30 Rewrite the wait loop to check the above condition directly with client->monc.mutex and client->osdc.lock taken as appropriate. While at it, improve the timeout handling (previously mount_timeout could be exceeded in case wait_event_interruptible_timeout() slept more than once) and access client->auth_err under client->monc.mutex to match how it's set in finish_auth(). monmap_show() and osdmap_show() now take the respective lock before accessing the map as well.

Exploit probability Not scored
Published December 16, 2025
Required by Not available
Last source change August 19, 2026

02 / AFFECTED SOFTWARE

Affected packages

Ubuntu:Pro:14.04:LTS linux-aws

120 explicit affected versions

Ubuntu:22.04:LTS linux-nvidia-tegra-igx

36 explicit affected versions

Ubuntu:Pro:FIPS:20.04:LTS linux-aws-fips

1 explicit affected versions

Ubuntu:22.04:LTS linux-lowlatency

87 explicit affected versions

Ubuntu:24.04:LTS linux-nvidia-lowlatency

34 explicit affected versions

Ubuntu:Pro:FIPS:20.04:LTS linux-fips

1 explicit affected versions

Ubuntu:Pro:FIPS-updates:18.04:LTS linux-fips

98 explicit affected versions

Ubuntu:Pro:FIPS:20.04:LTS linux-gcp-fips

1 explicit affected versions

Ubuntu:22.04:LTS linux-hwe-6.2

10 explicit affected versions

Ubuntu:24.04:LTS linux-lowlatency-hwe-6.11

7 explicit affected versions

Ubuntu:22.04:LTS linux-ibm

80 explicit affected versions

Ubuntu:18.04:LTS linux-oem

50 explicit affected versions

Ubuntu:18.04:LTS linux-aws-5.0

6 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-azure-fde-5.15

57 explicit affected versions

Ubuntu:24.04:LTS linux-riscv

24 explicit affected versions

Ubuntu:22.04:LTS linux-riscv-6.5

10 explicit affected versions

Ubuntu:Pro:Realtime:24.04:LTS linux-realtime

39 explicit affected versions

Ubuntu:22.04:LTS linux-lowlatency-hwe-6.5

13 explicit affected versions

Ubuntu:18.04:LTS linux-oracle-5.3

9 explicit affected versions

Ubuntu:25.10 linux-aws

10 explicit affected versions

Ubuntu:22.04:LTS linux-hwe-5.19

11 explicit affected versions

Ubuntu:Pro:Realtime:22.04:LTS linux-realtime

81 explicit affected versions

Ubuntu:25.10 linux

13 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-hwe

167 explicit affected versions

Ubuntu:22.04:LTS linux-starfive-6.5

11 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-iot

53 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-azure

116 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-hwe-5.4

120 explicit affected versions

Ubuntu:20.04:LTS linux-aws-5.11

12 explicit affected versions

Ubuntu:22.04:LTS linux-oem-6.5

19 explicit affected versions

Ubuntu:24.04:LTS linux-hwe-6.14

10 explicit affected versions

Ubuntu:20.04:LTS linux-raspi2

6 explicit affected versions

Ubuntu:22.04:LTS linux

90 explicit affected versions

Ubuntu:22.04:LTS linux-gkeop

75 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-lowlatency-hwe-5.15

75 explicit affected versions

Ubuntu:Pro:FIPS-updates:20.04:LTS linux-fips

91 explicit affected versions

Ubuntu:22.04:LTS linux-azure

79 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-gcp-5.15

70 explicit affected versions

Ubuntu:22.04:LTS linux-ibm-6.8

30 explicit affected versions

Ubuntu:24.04:LTS linux-oem-6.8

26 explicit affected versions

Ubuntu:22.04:LTS linux-gke

82 explicit affected versions

Ubuntu:Pro:14.04:LTS linux

191 explicit affected versions

Ubuntu:22.04:LTS linux-azure-5.19

7 explicit affected versions

Ubuntu:22.04:LTS linux-raspi

77 explicit affected versions

Ubuntu:22.04:LTS linux-oracle-6.8

34 explicit affected versions

Ubuntu:22.04:LTS linux-gcp-6.5

13 explicit affected versions

Ubuntu:Pro:FIPS-updates:18.04:LTS linux-azure-fips

85 explicit affected versions

Ubuntu:24.04:LTS linux-nvidia

37 explicit affected versions

Ubuntu:20.04:LTS linux-oem-5.14

35 explicit affected versions

Ubuntu:Pro:FIPS-updates:22.04:LTS linux-gcp-fips

42 explicit affected versions

Ubuntu:22.04:LTS linux-nvidia-tegra

40 explicit affected versions

Ubuntu:20.04:LTS linux-gke-5.15

18 explicit affected versions

Ubuntu:Pro:FIPS-updates:22.04:LTS linux-azure-fips

35 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-oracle

118 explicit affected versions

Ubuntu:22.04:LTS linux-azure-fde

64 explicit affected versions

Ubuntu:24.04:LTS linux-oracle

39 explicit affected versions

Ubuntu:20.04:LTS linux-aws-5.13

13 explicit affected versions

Ubuntu:20.04:LTS linux-aws-5.8

4 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-kvm

121 explicit affected versions

Ubuntu:16.04:LTS linux-hwe-edge

23 explicit affected versions

Ubuntu:24.04:LTS linux

45 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-gcp

124 explicit affected versions

Ubuntu:Pro:FIPS:18.04:LTS linux-gcp-fips

1 explicit affected versions

Ubuntu:24.04:LTS linux-raspi-realtime

1 explicit affected versions

Ubuntu:20.04:LTS linux-hwe-5.8

21 explicit affected versions

Ubuntu:22.04:LTS linux-azure-fde-6.8

9 explicit affected versions

Ubuntu:20.04:LTS linux-hwe-5.13

16 explicit affected versions

Ubuntu:22.04:LTS linux-lowlatency-hwe-6.2

10 explicit affected versions

Ubuntu:Pro:FIPS-updates:20.04:LTS linux-aws-fips

76 explicit affected versions

Ubuntu:24.04:LTS linux-aws

41 explicit affected versions

Ubuntu:24.04:LTS linux-hwe-6.11

8 explicit affected versions

Ubuntu:18.04:LTS linux-oracle-5.0

7 explicit affected versions

Ubuntu:20.04:LTS linux-riscv

12 explicit affected versions

Ubuntu:24.04:LTS linux-oracle-6.14

11 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-oracle

111 explicit affected versions

Ubuntu:24.04:LTS linux-azure-6.11

7 explicit affected versions

Ubuntu:20.04:LTS linux-gcp-5.11

12 explicit affected versions

Ubuntu:22.04:LTS linux-azure-6.5

14 explicit affected versions

Ubuntu:25.10 linux-azure-fde

10 explicit affected versions

Ubuntu:22.04:LTS linux-intel-iot-realtime

1 explicit affected versions

Ubuntu:20.04:LTS linux-intel-5.13

7 explicit affected versions

Ubuntu:24.04:LTS linux-nvidia-tegra

9 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-azure-5.4

104 explicit affected versions

Ubuntu:20.04:LTS linux-oem-5.13

12 explicit affected versions

Ubuntu:24.04:LTS linux-oracle-6.17

2 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-raspi

105 explicit affected versions

Ubuntu:20.04:LTS linux-oracle-5.11

12 explicit affected versions

Ubuntu:Pro:Realtime:22.04:LTS linux-realtime-6.8

34 explicit affected versions

Ubuntu:24.04:LTS linux-oem-6.14

16 explicit affected versions

Ubuntu:25.10 linux-gcp

10 explicit affected versions

Ubuntu:22.04:LTS linux-azure-6.8

23 explicit affected versions

Ubuntu:24.04:LTS linux-gkeop

27 explicit affected versions

Ubuntu:18.04:LTS linux-hwe-edge

10 explicit affected versions

Ubuntu:18.04:LTS linux-gke-5.4

37 explicit affected versions

Ubuntu:24.04:LTS linux-azure-nvidia

10 explicit affected versions

Ubuntu:24.04:LTS linux-gcp-6.17

2 explicit affected versions

Ubuntu:22.04:LTS linux-oracle-6.5

13 explicit affected versions

Ubuntu:22.04:LTS linux-lowlatency-hwe-6.8

33 explicit affected versions

Ubuntu:24.04:LTS linux-azure-nvidia-6.14

3 explicit affected versions

Ubuntu:22.04:LTS linux-azure-fde-6.2

10 explicit affected versions

Ubuntu:24.04:LTS linux-gcp-6.14

11 explicit affected versions

Ubuntu:Pro:Realtime:22.04:LTS linux-intel-iot-realtime

57 explicit affected versions

Ubuntu:20.04:LTS linux-oem-5.10

26 explicit affected versions

Ubuntu:Pro:FIPS-updates:24.04:LTS linux-azure-fips

5 explicit affected versions

Ubuntu:20.04:LTS linux-gcp-5.13

13 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-aws

144 explicit affected versions

Ubuntu:24.04:LTS linux-riscv-6.14

12 explicit affected versions

Ubuntu:22.04:LTS linux-xilinx-zynqmp

29 explicit affected versions

Ubuntu:Pro:FIPS:18.04:LTS linux-fips

1 explicit affected versions

Ubuntu:20.04:LTS linux-oem-5.6

29 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-gcp-5.4

111 explicit affected versions

Ubuntu:18.04:LTS linux-gcp-5.3

13 explicit affected versions

Ubuntu:22.04:LTS linux-gcp-6.8

34 explicit affected versions

Ubuntu:24.04:LTS linux-riscv-6.17

1 explicit affected versions

Ubuntu:Pro:FIPS:18.04:LTS linux-azure-fips

1 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-raspi-5.4

100 explicit affected versions

Ubuntu:22.04:LTS linux-aws

82 explicit affected versions

Ubuntu:Pro:FIPS-updates:22.04:LTS linux-aws-fips

45 explicit affected versions

Ubuntu:18.04:LTS linux-gke-4.15

33 explicit affected versions

Ubuntu:22.04:LTS linux-riscv

23 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-ibm-5.15

51 explicit affected versions

Ubuntu:25.10 linux-azure

9 explicit affected versions

Ubuntu:24.04:LTS linux-azure-fde-6.14

5 explicit affected versions

Ubuntu:18.04:LTS linux-aws-5.3

10 explicit affected versions

Ubuntu:Pro:FIPS-updates:24.04:LTS linux-fips

13 explicit affected versions

Ubuntu:Pro:16.04:LTS linux

188 explicit affected versions

Ubuntu:Pro:FIPS-updates:24.04:LTS linux-gcp-fips

12 explicit affected versions

Ubuntu:Nvidia-BlueField:24.04:LTS linux-bluefield

11 explicit affected versions

Ubuntu:24.04:LTS linux-azure

32 explicit affected versions

Ubuntu:20.04:LTS linux-hwe-5.11

12 explicit affected versions

Ubuntu:Pro:Realtime:24.04:LTS linux-realtime-6.17

2 explicit affected versions

Ubuntu:20.04:LTS linux-azure-5.8

7 explicit affected versions

Ubuntu:22.04:LTS linux-gcp-6.2

12 explicit affected versions

Ubuntu:24.04:LTS linux-hwe-6.17

1 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-gcp

138 explicit affected versions

Ubuntu:Pro:FIPS:16.04:LTS linux-fips

2 explicit affected versions

Ubuntu:24.04:LTS linux-azure-6.14

5 explicit affected versions

Ubuntu:22.04:LTS linux-nvidia

67 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-kvm

132 explicit affected versions

Ubuntu:Pro:FIPS-preview:22.04:LTS linux-azure-fips

1 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-intel-iotg-5.15

59 explicit affected versions

Ubuntu:22.04:LTS linux-oracle

83 explicit affected versions

Ubuntu:Pro:14.04:LTS linux-lts-xenial

165 explicit affected versions

Ubuntu:Pro:18.04:LTS linux

154 explicit affected versions

Ubuntu:22.04:LTS linux-lowlatency-hwe-5.19

10 explicit affected versions

Ubuntu:22.04:LTS linux-oem-5.17

26 explicit affected versions

Ubuntu:22.04:LTS linux-hwe-6.8

28 explicit affected versions

Ubuntu:24.04:LTS linux-raspi

40 explicit affected versions

Ubuntu:24.04:LTS linux-aws-6.14

11 explicit affected versions

Ubuntu:24.04:LTS linux-aws-6.17

2 explicit affected versions

Ubuntu:22.04:LTS linux-azure-6.2

13 explicit affected versions

Ubuntu:24.04:LTS linux-ibm

39 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-aws

139 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-ibm-5.4

78 explicit affected versions

Ubuntu:22.04:LTS linux-oem-6.0

16 explicit affected versions

Ubuntu:22.04:LTS linux-kvm

81 explicit affected versions

Ubuntu:24.04:LTS linux-gcp

43 explicit affected versions

Ubuntu:Pro:FIPS-preview:22.04:LTS linux-aws-fips

2 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-aws-hwe

116 explicit affected versions

Ubuntu:22.04:LTS linux-azure-fde-5.19

3 explicit affected versions

Ubuntu:Pro:20.04:LTS linux

132 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-gcp-4.15

93 explicit affected versions

Ubuntu:Pro:FIPS:20.04:LTS linux-azure-fips

1 explicit affected versions

Ubuntu:24.04:LTS linux-gcp-6.11

7 explicit affected versions

Ubuntu:25.10 linux-riscv

8 explicit affected versions

Ubuntu:20.04:LTS linux-gke

51 explicit affected versions

Ubuntu:25.10 linux-oracle

9 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-azure-4.15

92 explicit affected versions

Ubuntu:24.04:LTS linux-oem-6.11

18 explicit affected versions

Ubuntu:Pro:FIPS:18.04:LTS linux-aws-fips

1 explicit affected versions

Ubuntu:Pro:Realtime:24.04:LTS linux-raspi-realtime

35 explicit affected versions

Ubuntu:20.04:LTS linux-azure-5.13

12 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-azure-5.15

66 explicit affected versions

Ubuntu:22.04:LTS linux-intel-iotg

70 explicit affected versions

Ubuntu:24.04:LTS linux-nvidia-6.17

3 explicit affected versions

Ubuntu:22.04:LTS linux-oem-6.1

27 explicit affected versions

Ubuntu:Nvidia-BlueField:22.04:LTS linux-bluefield

56 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-oracle

121 explicit affected versions

Ubuntu:24.04:LTS linux-nvidia-6.11

8 explicit affected versions

Ubuntu:22.04:LTS linux-nvidia-6.8

36 explicit affected versions

Ubuntu:22.04:LTS linux-gcp-5.19

8 explicit affected versions

Ubuntu:Pro:FIPS-updates:22.04:LTS linux-fips

47 explicit affected versions

Ubuntu:20.04:LTS linux-oracle-5.8

5 explicit affected versions

Ubuntu:22.04:LTS linux-riscv-5.19

8 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-oracle-5.4

110 explicit affected versions

Ubuntu:20.04:LTS linux-azure-5.11

13 explicit affected versions

Ubuntu:Pro:FIPS-updates:20.04:LTS linux-azure-fips

72 explicit affected versions

Ubuntu:22.04:LTS linux-starfive-5.19

7 explicit affected versions

Ubuntu:Pro:16.04:LTS linux-azure

140 explicit affected versions

Ubuntu:Pro:FIPS-updates:18.04:LTS linux-aws-fips

94 explicit affected versions

Ubuntu:20.04:LTS linux-riscv-5.8

10 explicit affected versions

Ubuntu:20.04:LTS linux-oracle-5.13

12 explicit affected versions

Ubuntu:Pro:Realtime:24.04:LTS linux-realtime-6.14

9 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-nvidia-tegra-5.15

30 explicit affected versions

Ubuntu:Pro:18.04:LTS linux-aws-5.4

108 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-bluefield

80 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-xilinx-zynqmp

56 explicit affected versions

Ubuntu:18.04:LTS linux-azure

44 explicit affected versions

Ubuntu:18.04:LTS linux-azure-5.3

16 explicit affected versions

Ubuntu:22.04:LTS linux-starfive-6.2

3 explicit affected versions

Ubuntu:20.04:LTS linux-riscv-5.11

13 explicit affected versions

Ubuntu:20.04:LTS linux-azure-fde

26 explicit affected versions

Ubuntu:20.04:LTS linux-gkeop-5.15

45 explicit affected versions

Ubuntu:18.04:LTS linux-gkeop-5.4

37 explicit affected versions

Ubuntu:24.04:LTS linux-lowlatency

44 explicit affected versions

Ubuntu:22.04:LTS linux-aws-6.5

14 explicit affected versions

Ubuntu:18.04:LTS linux-gcp

38 explicit affected versions

Ubuntu:22.04:LTS linux-riscv-6.8

32 explicit affected versions

Ubuntu:24.04:LTS linux-xilinx

15 explicit affected versions

Ubuntu:25.10 linux-raspi

7 explicit affected versions

Ubuntu:22.04:LTS linux-gcp

83 explicit affected versions

Ubuntu:24.04:LTS linux-azure-fde

8 explicit affected versions

Ubuntu:22.04:LTS linux-nvidia-6.2

7 explicit affected versions

Ubuntu:Pro:FIPS:16.04:LTS linux-fips

97 explicit affected versions

Ubuntu:Pro:14.04:LTS linux-azure

121 explicit affected versions

Ubuntu:20.04:LTS linux-gcp-5.8

4 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-riscv-5.15

72 explicit affected versions

Ubuntu:24.04:LTS linux-azure-6.17

1 explicit affected versions

Ubuntu:24.04:LTS linux-realtime

1 explicit affected versions

Ubuntu:Pro:FIPS-preview:22.04:LTS linux-fips

1 explicit affected versions

Ubuntu:Pro:FIPS-preview:22.04:LTS linux-gcp-fips

1 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-hwe-5.15

72 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-aws-5.15

71 explicit affected versions

Ubuntu:22.04:LTS linux-hwe-6.5

13 explicit affected versions

Ubuntu:18.04:LTS linux-hwe

43 explicit affected versions

Ubuntu:Pro:FIPS-updates:20.04:LTS linux-gcp-fips

77 explicit affected versions

Ubuntu:24.04:LTS linux-oem-6.17

8 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-kvm

119 explicit affected versions

Ubuntu:22.04:LTS linux-aws-5.19

10 explicit affected versions

Ubuntu:22.04:LTS linux-allwinner-5.19

8 explicit affected versions

Ubuntu:24.04:LTS linux-gke

38 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-ibm

88 explicit affected versions

Ubuntu:22.04:LTS linux-aws-6.2

14 explicit affected versions

Ubuntu:18.04:LTS linux-azure-edge

4 explicit affected versions

Ubuntu:20.04:LTS linux-gkeop

78 explicit affected versions

Ubuntu:25.10 linux-realtime

7 explicit affected versions

Ubuntu:22.04:LTS linux-nvidia-6.5

11 explicit affected versions

Ubuntu:22.04:LTS linux-realtime

1 explicit affected versions

Ubuntu:Pro:FIPS-updates:18.04:LTS linux-gcp-fips

69 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-aws

123 explicit affected versions

Ubuntu:Pro:FIPS-updates:24.04:LTS linux-aws-fips

12 explicit affected versions

Ubuntu:22.04:LTS linux-aws-6.8

32 explicit affected versions

Ubuntu:Pro:20.04:LTS linux-oracle-5.15

71 explicit affected versions

03 / CONNECTIONS

Connected vulnerabilities

04 / EVIDENCE

Source records

Open Source Vulnerabilities UBUNTU-CVE-2025-68285

In the Linux kernel, the following vulnerability has been resolved: libceph: fix potential use-after-free in have_mon_and_osd_map() The wait loop in __ceph_open_session() can race with the client receiving a new monmap or osdmap shortly after the initial map is received. Both ceph_monc_handle_map() and handle_one_map() install a new map immediately after freeing the old one kfree(monc->monmap); monc->monmap = monmap; ceph_osdmap_destroy(osdc->osdmap); osdc->osdmap = newmap; under client->monc.mutex and client->osdc.lock respectively, but because neither is taken in have_mon_and_osd_map() it's possible for client->monc.monmap->epoch and client->osdc.osdmap->epoch arms in client->monc.monmap && client->monc.monmap->epoch && client->osdc.osdmap && client->osdc.osdmap->epoch; condition to dereference an already freed map. This happens to be reproducible with generic/395 and generic/397 with KASAN enabled: BUG: KASAN: slab-use-after-free in have_mon_and_osd_map+0x56/0x70 Read of size 4 at addr ffff88811012d810 by task mount.ceph/13305 CPU: 2 UID: 0 PID: 13305 Comm: mount.ceph Not tainted 6.14.0-rc2-build2+ #1266 ... Call Trace: <TASK> have_mon_and_osd_map+0x56/0x70 ceph_open_session+0x182/0x290 ceph_get_tree+0x333/0x680 vfs_get_tree+0x49/0x180 do_new_mount+0x1a3/0x2d0 path_mount+0x6dd/0x730 do_mount+0x99/0xe0 __do_sys_mount+0x141/0x180 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> Allocated by task 13305: ceph_osdmap_alloc+0x16/0x130 ceph_osdc_init+0x27a/0x4c0 ceph_create_client+0x153/0x190 create_fs_client+0x50/0x2a0 ceph_get_tree+0xff/0x680 vfs_get_tree+0x49/0x180 do_new_mount+0x1a3/0x2d0 path_mount+0x6dd/0x730 do_mount+0x99/0xe0 __do_sys_mount+0x141/0x180 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 9475: kfree+0x212/0x290 handle_one_map+0x23c/0x3b0 ceph_osdc_handle_map+0x3c9/0x590 mon_dispatch+0x655/0x6f0 ceph_con_process_message+0xc3/0xe0 ceph_con_v1_try_read+0x614/0x760 ceph_con_workfn+0x2de/0x650 process_one_work+0x486/0x7c0 process_scheduled_works+0x73/0x90 worker_thread+0x1c8/0x2a0 kthread+0x2ec/0x300 ret_from_fork+0x24/0x40 ret_from_fork_asm+0x1a/0x30 Rewrite the wait loop to check the above condition directly with client->monc.mutex and client->osdc.lock taken as appropriate. While at it, improve the timeout handling (previously mount_timeout could be exceeded in case wait_event_interruptible_timeout() slept more than once) and access client->auth_err under client->monc.mutex to match how it's set in finish_auth(). monmap_show() and osdmap_show() now take the respective lock before accessing the map as well.

View original source

05 / REFERENCES

Further evidence