// For flags

CVE-2024-40952

ocfs2: fix NULL pointer dereference in ocfs2_journal_dirty()

Severity Score

5.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix NULL pointer dereference in ocfs2_journal_dirty() bdev->bd_super has been removed and commit 8887b94d9322 change the usage
from bdev->bd_super to b_assoc_map->host->i_sb. This introduces the
following NULL pointer dereference in ocfs2_journal_dirty() since
b_assoc_map is still not initialized. This can be easily reproduced by
running xfstests generic/186, which simulate no more credits. [ 134.351592] BUG: kernel NULL pointer dereference, address: 0000000000000000
...
[ 134.355341] RIP: 0010:ocfs2_journal_dirty+0x14f/0x160 [ocfs2]
...
[ 134.365071] Call Trace:
[ 134.365312] <TASK>
[ 134.365524] ? __die_body+0x1e/0x60
[ 134.365868] ? page_fault_oops+0x13d/0x4f0
[ 134.366265] ? __pfx_bit_wait_io+0x10/0x10
[ 134.366659] ? schedule+0x27/0xb0
[ 134.366981] ? exc_page_fault+0x6a/0x140
[ 134.367356] ? asm_exc_page_fault+0x26/0x30
[ 134.367762] ? ocfs2_journal_dirty+0x14f/0x160 [ocfs2]
[ 134.368305] ? ocfs2_journal_dirty+0x13d/0x160 [ocfs2]
[ 134.368837] ocfs2_create_new_meta_bhs.isra.51+0x139/0x2e0 [ocfs2]
[ 134.369454] ocfs2_grow_tree+0x688/0x8a0 [ocfs2]
[ 134.369927] ocfs2_split_and_insert.isra.67+0x35c/0x4a0 [ocfs2]
[ 134.370521] ocfs2_split_extent+0x314/0x4d0 [ocfs2]
[ 134.371019] ocfs2_change_extent_flag+0x174/0x410 [ocfs2]
[ 134.371566] ocfs2_add_refcount_flag+0x3fa/0x630 [ocfs2]
[ 134.372117] ocfs2_reflink_remap_extent+0x21b/0x4c0 [ocfs2]
[ 134.372994] ? inode_update_timestamps+0x4a/0x120
[ 134.373692] ? __pfx_ocfs2_journal_access_di+0x10/0x10 [ocfs2]
[ 134.374545] ? __pfx_ocfs2_journal_access_di+0x10/0x10 [ocfs2]
[ 134.375393] ocfs2_reflink_remap_blocks+0xe4/0x4e0 [ocfs2]
[ 134.376197] ocfs2_remap_file_range+0x1de/0x390 [ocfs2]
[ 134.376971] ? security_file_permission+0x29/0x50
[ 134.377644] vfs_clone_file_range+0xfe/0x320
[ 134.378268] ioctl_file_clone+0x45/0xa0
[ 134.378853] do_vfs_ioctl+0x457/0x990
[ 134.379422] __x64_sys_ioctl+0x6e/0xd0
[ 134.379987] do_syscall_64+0x5d/0x170
[ 134.380550] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 134.381231] RIP: 0033:0x7fa4926397cb
[ 134.381786] Code: 73 01 c3 48 8b 0d bd 56 38 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8d 56 38 00 f7 d8 64 89 01 48
[ 134.383930] RSP: 002b:00007ffc2b39f7b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[ 134.384854] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fa4926397cb
[ 134.385734] RDX: 00007ffc2b39f7f0 RSI: 000000004020940d RDI: 0000000000000003
[ 134.386606] RBP: 0000000000000000 R08: 00111a82a4f015bb R09: 00007fa494221000
[ 134.387476] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[ 134.388342] R13: 0000000000f10000 R14: 0000558e844e2ac8 R15: 0000000000f10000
[ 134.389207] </TASK> Fix it by only aborting transaction and journal in ocfs2_journal_dirty()
now, and leave ocfs2_abort() later when detecting an aborted handle,
e.g. start next transaction. Also log the handle details in this case.

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix NULL pointer dereference in ocfs2_journal_dirty() bdev->bd_super has been removed and commit 8887b94d9322 change the usage from bdev->bd_super to b_assoc_map->host->i_sb. This introduces the following NULL pointer dereference in ocfs2_journal_dirty() since b_assoc_map is still not initialized. This can be easily reproduced by running xfstests generic/186, which simulate no more credits. [ 134.351592] BUG: kernel NULL pointer dereference, address: 0000000000000000 ... [ 134.355341] RIP: 0010:ocfs2_journal_dirty+0x14f/0x160 [ocfs2] ... [ 134.365071] Call Trace: [ 134.365312] <TASK> [ 134.365524] ? __die_body+0x1e/0x60 [ 134.365868] ? page_fault_oops+0x13d/0x4f0 [ 134.366265] ? __pfx_bit_wait_io+0x10/0x10 [ 134.366659] ? schedule+0x27/0xb0 [ 134.366981] ? exc_page_fault+0x6a/0x140 [ 134.367356] ? asm_exc_page_fault+0x26/0x30 [ 134.367762] ? ocfs2_journal_dirty+0x14f/0x160 [ocfs2] [ 134.368305] ? ocfs2_journal_dirty+0x13d/0x160 [ocfs2] [ 134.368837] ocfs2_create_new_meta_bhs.isra.51+0x139/0x2e0 [ocfs2] [ 134.369454] ocfs2_grow_tree+0x688/0x8a0 [ocfs2] [ 134.369927] ocfs2_split_and_insert.isra.67+0x35c/0x4a0 [ocfs2] [ 134.370521] ocfs2_split_extent+0x314/0x4d0 [ocfs2] [ 134.371019] ocfs2_change_extent_flag+0x174/0x410 [ocfs2] [ 134.371566] ocfs2_add_refcount_flag+0x3fa/0x630 [ocfs2] [ 134.372117] ocfs2_reflink_remap_extent+0x21b/0x4c0 [ocfs2] [ 134.372994] ? inode_update_timestamps+0x4a/0x120 [ 134.373692] ? __pfx_ocfs2_journal_access_di+0x10/0x10 [ocfs2] [ 134.374545] ? __pfx_ocfs2_journal_access_di+0x10/0x10 [ocfs2] [ 134.375393] ocfs2_reflink_remap_blocks+0xe4/0x4e0 [ocfs2] [ 134.376197] ocfs2_remap_file_range+0x1de/0x390 [ocfs2] [ 134.376971] ? security_file_permission+0x29/0x50 [ 134.377644] vfs_clone_file_range+0xfe/0x320 [ 134.378268] ioctl_file_clone+0x45/0xa0 [ 134.378853] do_vfs_ioctl+0x457/0x990 [ 134.379422] __x64_sys_ioctl+0x6e/0xd0 [ 134.379987] do_syscall_64+0x5d/0x170 [ 134.380550] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 134.381231] RIP: 0033:0x7fa4926397cb [ 134.381786] Code: 73 01 c3 48 8b 0d bd 56 38 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8d 56 38 00 f7 d8 64 89 01 48 [ 134.383930] RSP: 002b:00007ffc2b39f7b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 134.384854] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fa4926397cb [ 134.385734] RDX: 00007ffc2b39f7f0 RSI: 000000004020940d RDI: 0000000000000003 [ 134.386606] RBP: 0000000000000000 R08: 00111a82a4f015bb R09: 00007fa494221000 [ 134.387476] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 134.388342] R13: 0000000000f10000 R14: 0000558e844e2ac8 R15: 0000000000f10000 [ 134.389207] </TASK> Fix it by only aborting transaction and journal in ocfs2_journal_dirty() now, and leave ocfs2_abort() later when detecting an aborted handle, e.g. start next transaction. Also log the handle details in this case.

Chenyuan Yang discovered that the CEC driver driver in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. It was discovered that the JFS file system contained an out-of-bounds read vulnerability when printing xattr debug information. A local attacker could use this to cause a denial of service.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
Single
Confidentiality
None
Integrity
None
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-07-12 CVE Reserved
  • 2024-07-12 CVE Published
  • 2024-12-19 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.6.36
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.6.36"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.9.7
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.9.7"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.10
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.10"
en
Affected